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Thomas & Betts Corporation, Steel Structures Division, 8155 T&B Blvd, Memphis, TN 38125, 800-888-0211

• Life Cycle Costs

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• Wood vs. Steel

• Aesthetics

• Concrete vs. Steel

• Reduced Maintenance Cost

• Ease of Construction

• Reliability

• DC Poles

• LD H-Frames

Case Study No. 1: Engineering Firm Finds LD Steel Has Lowest Life-Cycle Costs

Case Study No. 2: LD Steel Is Cost Competitive With Wood On Sho-Me System

Case Study No. 3: Replacing Old Wood Poles With LD Steel Reduces Long-Term Maintenance Costs

Case Study No. 4: LD Steel Replaces Old Wood Structures On Idaho Power 345 kV Line

Case Study No. 5: Pennsylvania Power & Light Stocks LD Steel Poles For Replacing Wood

Case Study No. 6: LD Steel Poles Solve Aesthetic Concerns And Create Right-Of-Way Options

Case Study No. 7: Comparison Finds LD Steel Structures More Economical Than Concrete

Case Study No. 8: Dyersburg Electric System Sets A New Steel Standard

Case Study No. 9: Compressed Construction Schedule, Low Maintenance Gave Edge To Steel

Case Study No. 10: Steel Distribution Class Poles Solve Problems For Pierce-Pepin

Case Study No. 11: Super Fast Delivery Of LD Poles Key To Timely Repair Of Major Line

Case Study No. 12: LD Poles Solve Special Problems For Kentucky Utilities’ System

Case Study No. 13: Meyer LD Steel Poles Save Money On 138 kV to Laredo

Case Study No. 14: Meyer Distribution Class Steel Poles Supply Power To Growing County Complex

Case Study No. 15: Meyer LD Steel Poles Solve Distribution Line Problems

Case Study No. 16: Town Solves Complex Problems With First LD Steel Project

Case Study No. 17: Meyer LD H-frame: Cost Effective Alternative

Case Study No. 18: Delivery Key To Selecting Steel Poles For Nantahala Project

Case Study No. 19: LD Quick SpliceTM Yields Big Savings For Memphis Light, Gas & Water

Case Study No. 20: LD Poles Chosen Over Wood In 115 kV Reconstruction

Case Study No. 23: Manitoba Hydro Turns to LD for Lower Costs and Improved Longevity in New Line

Case Study No. 22: Avista Puts LD to the Test Tough Rural Washington Upgrade

Case Study No. 25: City of Saskatoon Successfully Upgrades 72 kV Wood Poles With 138 kV Tubular Steel

Case Study No. 24: Steel Conquers Kelowna West Kootenay Power Chooses Steel Poles for Power Upgrade

Case Study No. 21: Steel H-frames Save Time, Costs, Rebuilding Line

Case Study No. 26: Steel Structures Withstand the Harshest Conditions and Can Be Produced More Quickly than Wooden H-Frames.HOME










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• Wood vs. Steel

• Aesthetics




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• DC Poles

• LD H-Frames



Wood vs. Steel















To access the case study click on the corresponding underlined link.



Case Study No. 26: Steel Structures Withstand the Harshest Conditions and Can Be Produced More Quickly than Wooden H-Frames.



• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

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Aesthetics















• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

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Concrete vs. Steel








• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

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Reduced Maintenance Cost






















• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

HOME


Ease of Construction





















• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

HOME


Reliability













• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

HOME


DC Poles







• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

HOME


LD H-Frames











• Wood vs. Steel

• Aesthetics




• Reliability

• DC Poles

• LD H-Frames

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Before specifying the structure material for the Shepherd-Coldspring 138 kV transmission

line belonging to the Sam Houston Electric Coop in east Texas, the engineering consulting firm performed an economic analysis. According to George Kithas, president of Cornelius Pierce Consulting Engineers, wood, concrete and steel were all analyzed in terms of initial cost, ease of construction, long-term maintenance, reliability, and overall life- cycle costs.

"We designed the line with spans and performance characteristics for wood poles, because that is a standard conservative practice when working with many Rural Electric Administration-financed projects," says Kithas. "Then we accepted bids from wood, steel and concrete structure suppliers and performed our economic analysis based on wood-pole equivalents."

What Kithas has found on several recent projects is that Meyer LD steel poles have come out on top of the economic analysis. "We consider initial cost, long-term maintenance requirements, reliability, transportation & construction issues, and aesthetics. Although steel is higher in initial cost, it more than makes up for that in low long-term maintenance and reliability," says Kithas. Construction is simplified with steel as well. Lighter than a comparable wood pole, LD steel can be installed using small crews and normal equipment.

The Shepherd-Coldspring 138 kV transmission line is typical of the transmission lines through the wooded, rolling hills of east Texas. It was designed with single-shaft poles with davit arms and suspended porcelain insulators. Structure spacing is 500-600 feet and based on wood or wood equivalents. Kithas says his firm and the coops favor the use of weathering steel for projects in east Texas, especially if they are along roads where they are in constant public view. "We find the weathering steel

blends very well with the wooded countryside."

Woodpeckers are the number one problem with wood structures in east Texas. Protecting wood poles with wire cloth costs from $150 to $200 per structure, according to Kithas, but that cost is eliminated with the use

of steel poles. A smaller problem with wood poles is groundline rot. Kithas recommends a periodic inspection of all transmission structures to hold down maintenance costs and improve reliability.

Engineering Firm Finds LD Steel Has Lowest Life-Cycle Costs

George KithasPresidentCornelius PierceConsulting Engineers9020 Hwy #377 SouthFort Worth, TX 76126

Case Study No. 1

"ALTHOUGH STEEL IS HIGHER IN

INITIAL COST, IT MORE THAN MAKES

UP FOR THAT IN LOW LONG-TERM

MAINTENANCE AND HIGH RELIABILITY."


HOME

Sho-me Power is currently using Meyer LD steel poles for selected new or rebuilt projects on 69 kV to

161 kV. Their cost analysis of yellow pine vs LD steel shows that the two materials are nearly identical on a first-cost basis. Although Arndt says Sho-me has not done any long-term cost analysis on wood vs LD steel, he is confident that the long-term maintenance costs for steel would show a savings over wood due to lower maintenance costs.

One current LD steel project in the Lake of the Ozarks area of southern Missouri is a 4.6 mile, 69 kV radial tap to serve a new substation. The Ozarks area is a popular resort area and tourist destination, and power needs continue to grow. The line will feature direct-embedded, two-piece Meyer LD weathering steel poles. The direct-embedded poles will be in two pieces due to the difficult terrain. They will support 336 mcm acsr conductors in a delta configuration using davit arms with suspension insulators. Sho-me favors LD steel in hilly areas due to the limited access for both construction and maintenance, Arndt says. Light weight LD poles allowed the utility to use a helicopter to set the poles on one recent project.

Another common use for LD poles on the Sho-me system is for phase-over-phase line switches. The Turner switch being used comes as a package with the Meyer LD steel pole, which is then direct-embedded. Arndt said this has become the defacto standard for phase-over-phase switches on their system.

The primary long-term maintenance problem on the Sho-me system is woodpecker damage. To cope with their damage on existing wood structures, Sho-me wraps the wood poles from the top to within eight feet of the groundline with hardware cloth, a very labor intensive operation. New wood structures up to 161 kV are now routinely equipped with this woodpecker protection. Older 69 kV wood poles are wrapped with hardware cloth when they are changed out.

Arndt says that 345 kV wood structures cannot be wrapped for protection from woodpeckers, so when the time comes to replace those structures, Sho-me will be looking very seriously at LD steel to reduce long term maintenance.

Terry ArndtChief ConstructionDesign EngineerSho-me PowerPOB DMarshfield, M0 65706

"SHO-ME FAVORS LD STEEL IN HILLY AREAS DUE TO THE

LIMITED ACCESS FOR BOTH CONSTRUCTION AND MAINTENANCE."

LD Steel Is Cost Competitive With Wood On Sho-Me System

Case Study No. 2


HOME

I n order to reduce long-term maintenance costs Carolina Power & Light has been using Meyer LD steel

poles to replace old wooden structures in poor access areas. According to CP&L Project Engineer, Rodney Hutcherson, replacement of woodpecker-damaged poles in areas of poor access is a significant maintenance cost for the utility. By replacing these individual poles with LD steel, the utility has reduced its long-term maintenance costs.

"All areas of our system have sections with poor access. The lakes in the Piedmont area present access problems. The swamps of the southeast, and the mountainous areas of the northwest have even greater access problems," says Hutcherson. Although wood poles have lower initial costs, the maintenance over the long term makes them potentially more expensive. "The woodpeckers that cause the damage to the wood poles on our system are endangered species," he says. "While we can't do anything about the problem

source, LD steel provides a reliable, cost effective solution that is environmentally compatible:"

Although the utility replaced damaged poles at 31 individual sites last year, Hutcherson says they do not maintain their own inventory of LD steel poles. Since these replacements are on a non-emergency basis, the utility has been satisfied with the delivery service.

Rodney HutchersonProject EngineerCarolina Power &

LightPOB 1551- 6C3Raleigh, NC 27602

Replacing Old Wood PolesWith LD Steel ReducesLong-Term Maintenance Cost

Case Study No. 3

"THE WOODPECKERS THAT CAUSE THE DAMAGE

TO THEWOOD POLES ON OUR SYSTEM ARE

ENDANGEREDSPECIES. LD STEEL

PROVIDES A RELIABLE, COST EFFECTIVE

SOLUTION THAT IS ENVIRONMENTALLY

COMPATIBLE."


HOME

Idaho Power's 80-mile-long Midpoint-Borah 345 kv transmission line was originally built in 1961 as a 230 kV

line on wood H-frames. Upgraded to 345 kV in the early 1970s, the line beganexperiencing higher than normaloutage rates and maintenance costsby the late 1980s, according to PatrickJ. Hasenoehrl, Supervisor of HighVoltage Transmission.

In 1991, Idaho Power began a major refurbishment of the line, which, among other things, included complete

replacement of 84 structures. The goal of the utility was to get another 30 years of life from the line before reconsidering total replacement. Meyer LD weathering steel H-frames were chosen for the structures for a variety of reasons, says Hasenoehrl.

"At the time we were planning the refurbishment, western red cedar and Douglas fir poles of the size needed were in short supply and expensive," he says. "Our analysis of life-cycle costs

for different structure materials showed that LD steel came out as less expensive – not even counting the higher level of reliability afforded by steel."

A number of recent outages on the line had been caused by fires – either grass fires or cross-arm fires. Other problems were leaning poles, deteriorated and fractured poles, and assorted problems associated with the aging of the line. Steel structures eliminated these problems.

Another threat in that part of the country are ice storms and high winds, which can cause major outages due to structure or conductor failure. "We used steel tangent dead-ends in a number of locations on the line to prevent cascading," says Hasenoehrl.

For new lines of 345 kV and above, Hasenoehrl says Idaho Power specifies the use of steel structures. Below 345 kV, projects are looked at on a case-by-case basis.

Patrick J. HasenoehrlSupervisor of High

VoltageTransmission

EngineeringIdaho Power

CompanyPOB 70 Boise, ID 83707

LD Steel Replaces Old Wood Structures On Idaho Power 345 kV Line

Case Study No. 4

"OUR ANALYSIS OF LIFE-CYCLE COSTS

SHOWED THAT LD STEEL CAME

OUT AS LESS EXPENSIVE – NOTEVEN COUNTING

THE HIGHER LEVEL OF RELIABILITY

AFFORDEDBY STEEL."


HOME

Using steel poles as a direct replacement of a wood pole used to be a rarity, according

to Jim Rarig, Manager of Transmission Engineering for Pennsylvania Power & Light, but it's "normal now." PP&L currently has an ongoing program of using Meyer LD steel poles to replace large Douglas fir poles.

Fir has not performed well in the East-central area of Pennsylvania, according to Rarig. When fir "checks," it exposes the untreated inner parts of the wood and then tends to deteriorate from the inside-out. "We've been replacing approximately 250 poles per year with steel. At this rate of usage, we find it better to maintain an inventory of LD steel poles in sizes from 60-110 feet in length."

Rarig says that LD steel offers the utility design flexibility, as well as lower life-cycle costs and higher reliability. "Up to lengths of about 80 feet, all of our LD poles are one-piece. Over that length, they are two-piece with a bolted flange. This allows us to mix and match bottoms and tops to get the right size and performance – effectively stretching the size of our inventory."

LD steel has also been readily accepted by PP&L's construction crews. At less than half the weight of a comparable-sized wood pole, LD steel poles are easily erected using small crews and normal equipment. All of the LD poles used by PP&L are made in weathering steel. Approximately 10% of the poles may be painted on-site, especially when they are used in commercial areas.

For entirely new lines, Rarig says that LD steel is viewed favorably too. "People – especially in agricultural areas – like fewer structures, and that means longer spans. To get those longer spans and minimize guying, you need the higher strength and reliability of steel," Rarig concludes.

Pennsylvania Power & Light Stocks LD Steel Poles For Replacing Wood

Jim RarigManager of

Transmission Engineering

Pennsylvania Power & Light

2 N. 9th StreetAllentown, PA 18101

Case Study No. 5

"AT LESS THANHALF THE

WEIGHT OF A COMPARABLE-SIZED

WOOD POLE, LD STEEL POLES ARE EASILY

ERECTED USING SMALLCREWS AND NORMAL

EQUIPMENT.”


HOME

Ron Predovich Manager of

Transmission & Construction

Cooperative Power Association

Eden Prairie, MN 55337

In a recently completed transmission project in Eagan, MN, the use of Meyer LD steel poles was instrumental

in getting good cooperation from city officials and land owners. In addition, the use of LD steel poles allowed the use of existing railroad right-of-way, thereby minimizing impact on surrounding residential and agricultural land.

Cooperative Power designed and managed the project for its member cooperative, Dakota Electric Association. This 3.77 mile line taps an existing 69 kV which feeds the new Wescott Park substation, and then continues on to another 69 kV line, which completes the loop-feed to the new sub. For 1.5 miles of the line, there are Dakota Electric Association distribution circuits on the weathering steel structures with numerous underground risers to feed residential areas. This LD project is currently the longest all-LD steel transmission line in Minnesota.

For about 1.5 miles, the line follows Wescott Road, a four lane suburban boulevard which is a wide, east-west artery through the community. The new LD steel poles use the same right-of-way that was used for the existing distribution lines. Because of the residential character of the area, city officials expressed a preference for the use of steel poles on this project. Previous experiences by the city with steel transmission poles had been favorable, so there was interest in continuing their use in sensitive areas.

The LD poles range from 55 to 90 feet in height, and the majority of the poles are direct-embedded. Although most of the poles are standard LD steel designs, several dead-ends and heavy angles had to be specially built. The direct-embedded poles feature a black urethane protective coating to prevent corrosion, and a ground collar for added protection. All holes for mounting hardware were pre-drilled during manufacture, thereby reducing on-site work.

Another reason favoring the selection of LD steel for the project was the need to support a heavy three-phase underbuild and numerous underground risers and motorized switches.

Although the cost of LD steel was initially greater than it would have been with wood poles, steel allowed the cooperative the option of utilizing some existing railroad right-of-way for nearly half of the route. This greatly reduced

ROW acquisition costs and allowed the cooperative to confine any perceived visual impact to an existing corridor. In addition, the 1.5 miles of gently curving railroad track required self-supporting poles, since guying was not permitted. Steel also permitted slightly longer spans between poles in the rolling terrain, thereby reducing the overall number of structures as compared to wood.

LD Steel Poles Solve Aesthetic Concerns And Create Right-Of-Way Options

Case Study No. 6

“STEEL PERMITTEDSLIGHTLY LONGER SPANS BETWEEN

POLES IN THEROLLING TERRAIN,

THEREBY REDUCING THE

OVERALL NUMBER OF STRUCTURES AS

COMPARED TO WOOD.”


HOME

In a carefully documented comparison

between two transmission projects

over similar terrain, Carteret-Craven

found that Meyer LD single-shaft steel

transmission structures cost significantly

less than concrete structures when

compared on an installed per-pole basis.

Two lines were constructed along the

eastern North Carolina seaboard within a

year of each other, and both were 115 kV

with 12 kV underbuild. One was concrete;

one was LD steel. Sandy soil conditions

posed a stability problem for both pole

designs, which averaged 90 ft. tall. As a

result, all structures on both lines required

special foundations.

The concrete structure line was built

during 1991. Foundations consisted of

concrete cylinders up to 32 feet in length

and weighing up to 23,000 pounds. The

foundation holes in the sandy soil were

made using a wet-drilling method with

drilling mud. Crews could only complete

2-3 foundations per l0-hour day.

The steel structure line was built in 1992

and involved 7.5 miles of new construction

in similar sandy soil conditions. The

structures were galvanized Meyer LD

steel poles. Foundations consisted of steel

caissons installed with a vibratory hammer.

The ease with which the steel foundations

were installed was remarkable, according

to Carteret-Craven. The 3,500 pound

caissons for the steel pole foundations

could be installed in less than 30

minutes – including equipment setup and

take-down. Other cost-saving factors had to

do with delivery and stockpiling. Up to 12

LD steel pole bases and 18 tops could be

loaded onto a single flat-bed trailer. In

comparison, the weight of the concrete

poles would only allow for one pole per

trailer. Installation of the LD poles only

required one, 12-ton all-terrain crane and

minimal man-power.

The net savings with LD steel amounted

to approximately $3156 per structure. That

represented a savings to the cooperative

of $211,452 on this one project. Virtually

all of this savings was due to the low

weight of LD steel, its ease of handling

and uncomplicated construction methods,

according to the cooperative.

Craig Conrad. P.E.Manager of

Engineering &Operations

Comparison Finds LD Steel Structures More Economical Than Concrete

Case Study No. 7


COST COMPARISON OF STEEL VS. CONCRETE 115 KV TRANSMISSION STRUCTURES

No. Avg. Material Cost Avg. Labor Cost Avg. Total Cost

LD Steel 67 $7,209 $1,129 $8,338

Concrete 21 $7,146 $4,348 $11,494

Carteret -CravenElectric Membership

CooperativeHwy. 24 West, P.O. Box 1499Morehead City, NC

28557

HOME

The traditional wood pole power line is fast giving way to steel structures on the Dyersburg Electric System

(DES). A number of reasons caused the shift from the low, front-end cost wood products to the higher, initial expense of steel counterparts. And, all of the reasons have to do with lower life-cycle costs associated with steel.

Dyersburg has chosen Meyer Distribution Class (DC) steel poles for use on its system. The eightsided DC-2 steel poles are equivalent to Class 2 wood distribution poles in size and strength.

Although the delivered cost of Meyer DC steel poles is approximately three times that of wood poles, Dyersburg's research indicates that the steel units have a service life between three and fivc-times longer than wood. Additionally, the steel poles do not require long-term maintenance as do the wood poles on the DES system. DES inspects wood poles at and below ground line about every seven years for decay that leads to premature failure. Roughly tenpercent of the poles inspected have decayed to the point that replacement is required. The remaining 90% are chemically treated to enhance their remaining life expectancy at a cost of $15-$25 per pole. Steel poles, on the other hand, require no such on-going attention which significantly reduces their life-time cost to the system.

Steel is also superior in resisting mechanical damage from pests, storms, and accidents. The DES service area has a large woodpecker population, and wood poles are a favorite target for these protected birds. DES is constantly replacing woodpecker- damaged poles as a part of its routine maintenance program.

Other considerations that have led to Dyersburg's use of steel instead of wood have to do with appearance and performance. Wood poles are often irregular, while steel poles are attractive and uniform. DES uses self-weathering steel rather than galvanized and has found that the general public does not notice that the poles aren't wood.

Steel poles are now standard for the DES 69 kV subtransmission system. Replacement of any wood structure on the existing 69 kV lines is always with steel. New construction is also with steel in either self-supporting (anchor base) structures or direct-embedded units (with guying as required). One particular subtransmission application where DES prefers steel over wood is for switch structures.

DES, the public power provider for Dyersburg, TN and parts of Dyer County, TN since 1902, has extensive experience with utility poles. The recent shift from wood structures to steel DC poles represents its on-going effort to provide reliable and economical service to its customers.

Robert A. Smith Vice President,Engineering &

Construction Dyersburg Electric

System Dyersburg, TN 38025

Dyersburg Electric SystemSets A New Steel Standard

Case Study No. 8


HOME

Peoples Electric Cooperative (PEC) is a 16,000-member cooperative in south central Oklahoma. When

an opportunity arose for the coop to build a 138 kV transmission line to wheel power from the Southwest Power Administration to two wholesale customers, they moved quickly.

According to John Hudson, People's Manager of Operation, the transmission line covers 12.5 miles between Tupelo, OK, and Ada, linking a major switch station and new PEC substation. It features davit arm construction on single shaft Meyer LD poles. The line also carries a 25 kV underbuild circuit mounted on wood crossarms for eight miles. The average span between structures is 400 feet.

Hudson said with the project's short construction schedule, there was not enough time to wait for wood poles in the size and quantity needed. "The best solution to our compressed schedule and long-term maintenance concern was LD steel poles," says Hudson. "We didn't have the equipment necessary for on-going maintenance on a wood pole 138 kV transmission line. Over 75% of the poles would had to have been wire wrapped to protect against woodpecker damage – a serious problem in this area."

People's placed the order for the 175 Meyer LD steel poles, and in less than eight weeks the first steel poles started arriving. In less

than 11 weeks, all of the poles had been shipped.

The line has four 90° turns and four other heavy angles in order to follow abandoned railroad ROW and avoid sensitive pasture land, says Hudson. In addition, landowners originally expressed some resistance to the project, but seemed satisfied when single-shaft steel poles were selected, he says.

In addition to the compressed schedule, the Ada area experienced very wet weather during construction which complicated – but did not slow – the completion of the line. The line was energized on schedule. With his first experience with steel transmission lines behind him, Hudson says: "Steel poles are as easy to handle as wood."

John HudsonManager of

OperationsPeople's Electric

CooperativeP.O. Box 429Ada, OK 74820

Compressed ConstructionSchedule, Low MaintenanceGave Edge To Steel

Case Study No. 9

"THE BEST SOLUTION

TO OUR COMPRESSED

SCHEDULE AND LONG-TERM

MAINTENANCE CONCERNS

WAS LD STEEL."


HOME

When Pierce-Pepin Cooperative Electric needed to build a new three-phase distribution

line to service a growing section of it's service area, it chose to use Meyer DC (Distribution Class) steel poles to solve various, right-of-way problems. According to Jerry DeWolfe, Pierce-Pepin Construction Engineer, the project was the first steel pole distribution project on the cooperative's system.

"Housing was growing along the Mississippi River, there was a sand and gravel operation, a county hot-mix plant and a mixture of residential and commercial customers," says Jerry. "In addition, there were a number of constraints: railroad right-of-way, highway right-of-way, a wildlife sanctuary – all confined along the bluffs of the river. This created very tight quarters."

Pierce-Pepin is a member of the Dairyland Power Cooperative of LaCrosse, WI, a Generation and Transmission cooperative with 29 member coops in Wisconsin and Minnesota. Pierce-Pepin's customer base is composed of about 75 percent residential, 20 percent farm and 5 percent commercial and miscellaneous.

The line is approximately one mile in length and involved the use of 16 Meyer DC steel poles. Tangent structures averaged 40' in length; self-supporting angles averaged 50' in length; and some special purpose poles were 45' in length. All were made of self weathering steel to blend in with the existing wood distribution poles and the natural river bluff environment.

Since this was the first DC steel project for the cooperative, the construction process required some different steps. "Nylon slings we normally use for wood poles didn't work on the steel poles," says DeWolfe.

"After some experimentation, we decided to use a steel cable choker. Once the pole was upright and in place, the weight of the cable allowed it to slide easily back down the pole for removal."

Only one of the 16 poles was guyed, and all were direct-buried. A factory-applied urethane coating on the below-ground section of the poles provided a tough, corrosion proof barrier. Spans between poles were stretched from the coop's customary 250 feet to an average of 330 feet because of the higher strength of the steel poles. This reduced the number of poles by about 30 percent

over the number of wood poles that would have otherwise been required. But wood poles could not have been used in any case because of the right-of-way restrictions that eliminated guying as an option.

DeWolfe says the crews were impressed with the ease of erecting the DC steel poles. Many of the poles were pre-drilled during fabrication at the factory. "The time to frame and erect the poles was about half that for wood poles," says DeWolfe. Field drilling was accomplished with a magnetic drill that was both accurate and easy to operate. "The line went up like an erector set and that was a pleasant surprise."

Jerry DeWolfeConstruction

EngineerPierce-Pepin Electric

Cooperative

Steel Distribution Class Poles Solve Problems For Pierce-Pepin

Case Study No. 10

"THE TIME TO FRAME

AND ERECT THE POLES WAS ABOUT HALF THAT FOR WOOD

POLES."


HOME

In June of 1992, 100 mile per hour winds ripped through an area southeast of Tulsa, Oklahoma, taking out 2.5

miles of a 138 kV double circuit wood pole feeder line belonging to Public Service Company of Oklahoma. It was a critical line that was needed by the utility during the high peak demand on the system created by the summer air conditioning load. With this line out of service, several distribution substations were left with only one-way feeds. As soon as the storm subsided and the damage was assessed, the utility went to work to determine the fastest way to get it back on-line.

According to Phil Wright, Senior Engineer, the options for replacement structures were limited. "We no longer stocked the size of wood pole required for this size of line. And the lead time for wood was averaging about two to three months," says Wright. "Steel poles seemed to be our best option from the standpoints of size, strength, availability and construction schedule."

The storm occurred on a Friday. The next day, Saturday, Wright put in a call to Thomas & Betts to see how soon they could supply the 32 Meyer LD steel poles needed for direct replacement of the wood poles. "Needless to say, I was pleasantly surprised to learn they would start shipping the poles on Saturday from the Houston facility. They quoted a price over the phone and we had an agreement."

At the plant in Houston, extra crews were brought in on Saturday to complete fabrication of the LD poles which were taken directly from stock. Within ten hours from the initial call, all 32 LD poles were completed and shipped. The first truck load arrived Sunday morning and all trucks by late Sunday afternoon.

With new Meyer LD Steel Poles arriving on site within a day of placing the order, construction was able to begin immediately, says Wright. The weathering LD steel poles ranged from 90 to 100 feet and were direct equivalents of the wood poles they were replacing. Mounting holes for the steel davit arms that were used on the original wood line were drilled on site using a

magnetic drill.

"We were able to place the poles in virtually the same positions as the original wood poles," says Wright. "Each LD pole had a protective below-ground coating for direct burial. Because the soil in this area is rather sandy, each pole was then backfilled with concrete – a very fast and strong construction method that we use."

In only 10 days, the 2.5 mile line segment was repaired and energized – a record for this kind of restoration, according to Wright. The availability of stock LD poles made this possible.

Phil Wright Senior EngineerPublic Service Co.

of Oklahoma

Super Fast Delivery Of LD Poles Key To Timely Repair Of Major Line

Case Study No. 11


"STEEL POLES SEEMED TO

BE OUR BEST OPTION FROM THE STANDPOINTS OF SIZE, STRENGTH

AVAILABILITY AND CONSTRUCTION

SCHEDULE."

HOME

Kentucky Utilities Co. (KU) has used Meyer LD steel poles since they were first standardized

and introduced in 1984 for various transmission projects. In general, the utility has found them easy to install and maintain, and cost competitive with wood in most applications.

According to Mark Brewer, KU Project Engineer, the utility currently has a blanket order for LD steel poles for use in wood pole line maintenance and for solving special engineering problems.

A recent example involved an existing double-circuit 69 kV transmission line which crossed an active strip mine operation in the western part of the state. Strip mining in the vicinity of several lattice steel towers resulted in subsurface failures in the predominantly shale substructure.

These failures caused moderate to severe damage to these lattice towers. After much investigation and analysis, Meyer LD steel poles were found to be the answer to the problem.

Brewer says installing wood poles of that size and class would not have been less expensive than steel. "In addition, we wanted to keep the 69 kV structures all steel because wood poles have a significantly higher maintenance requirement than do steel structures.”

Another recent use involved a unique situation where LD poles provided the answer. It involved a 138 kV line crossing under an existing 138 kV double circuit line. Due to the high ground line moments and uplift problems, LD steel poles proved to be the preferred solution. The LD poles were set deep enough to handle the unbalanced loads and uplift conditions caused by conductor tensions.

“Having a blanket contract for Meyer LD steel poles for maintenance and special situations has saved KU a lot of money and time," concludes Brewer.

LD Poles Solve Special ProblemsFor Kentucky Utilities' System

Mark BrewerProject EngineerKentucky Utilities Co.

Case Study No. 12

“MEYER LD STEEL POLES

MADE IT POSSIBLE TO ROUTE THIS

69KV LINE IN A NARROW URBAN RIGHT OF WAY.”


HOME

The import/export business with Mexico is booming, and the city of Laredo, TX, is booming along with

it. In fact, electric load growth accelerated dramatically during the past few years, forcing Central Power & Light (CPL) of Corpus Christi, TX, to construct a 96.5 mile, 138 kV transmission line two years ahead of schedule.

Before construction started, CPL engaged Alexander Utility Engineering, Inc. (AUE) to do an economic evaluation of various structure options for the line. AUE evaluated natural wood, laminated wood,concrete and steel structures to find the lowest unit cost for each option. The study concluded that Meyer LD steel poles from Thomas & Betts provided the longest ruling spans and the lowest installed cost of all the options considered. LD steel poles represented a total project savings of $135,432 over concrete; a $908,072 savings over laminated wood structures; and a $1,099,768 savings over natural wood poles. In fact, savings could have been greater still if soil conditions had not limited the ruling span to 700 feet.

Begun in October, 1993 and completed in June, 1994, the line runs from the Dilley Switch Station near Dilley, TX, 96.5 miles to the Wormser Road Switch Station outside of Laredo. Four contractors were involved in its construction in order to allow energizing certain portions as it was built. The line is double circuit for the for 9.6 miles, and single circuit for the remaining 90 miles. It features single-shaft weathering steel LD-7 poles with davit arms and polymer insulators for all of the tangent structures. In addition, there are

approximately 40 heavy angle and deadend lattice steel structures along the line.About two thirds of the line was built on existing ROW of flat to gentle rolling hills. In the existing corridor, the line replaces a 69 kV line that was built in the 1920's and 1940’s. Doug Hill, CPL project engineer, says that replacing this old wood pole line "eliminated a bunch of maintenance headaches" for the utility. Woodpeckers are a major problem in this area and cause constant replacement of wood poles. The majority of the wood pole line was

unshielded and experienced in excess of 100 weather related interruptions per year.

One third of the line was on new ROW where the aesthetic appeal of steel poles played an important part in further lowering costs, he says "Structure type had a major impact on new ROW acquisition," says Hill. "LD steel poles allowed longer

spans, fewer structures and a 15 foot narrower ROW– which pleased a lot of landowners and lowered our costs. In addition, the weathering steel blends well with the environment."

Because of the light soil over most the route, concrete backfill was needed to increase the effective butt diameter of the poles and give additional stability, says Hill. "A span of up to 800 feet would have been possible with these LD poles, but soil conditions were not suitable."

Construction of the line took eight months and went very smoothly, according to Hill. Once under way, the contractors set an average of 14 structures per day, with a one day peak of 21 poles.

Doug HillEngineer,Transmission &

Substation Design

Meyer LD Steel Poles Save Money On 138 kV Line to Laredo

Case Study No. 13

"THE STUDY CONCLUDEDMEYER LD

STEEL POLES PROVIDED THE

LOWESTINSTALLED

COST."


HOME

When the Dyersburg Electric System (DES) needed to build a feeder line to a

growing community development park in Dyer County, TN, it chose Meyer DC (Distribution Class) steel poles from Thomas & Betts. The park consists of the Dyer Country Fair Grounds, a National Guard Armory, a public riding area and new Little League baseball fields. For a variety of reasons, DC steel poles were chosen over traditional wood or concrete poles as the best solution.

"Because this 13.2 kV line is a major feeder to the area, we decided to use DC steel poles due to steel's inherent reliability," says Robert Smith, Vice President of Engineering and Construction for DES. "The load on this line required heavy 336.4 ACSR conductors and a 3/0 ACSR neutral. Steel poles would allow us to carry the load and still maintain our desired spans of up to 250 feet." In addition, the 4,000 ft. line eventually will be extended to tie back into an existing line on the east side of Dyersburg, becoming a key link in a 13.2 kV loop around the city, he says.

The 16 DC steel poles used in the project were all 50 feet in height, protected with a urethane coating for the bottom 10 feet. All poles were direct embedded to a depth of seven feet and backfilled with native soil. The line follows road right-of-way and some guying was required on angles and deadends. The mounting hardware consisted of a fiberglass pole top pin and standard porcelain insulators. Smith said DES has been using that design on distribution voltages for about 20 years and found that they hold up well.

Each pole was equipped with a 1/2" stainless steel nut welded 12 inches above the ground line for grounding. On this line, the system neutral was bonded to

every steel pole, and DES installed an eight foot grounding rod at every pole. "We do this primarily for public safety," says Smith. "The below grade coating on the base of the pole is a partial insulator, so we ground each one to prevent the pole from becoming accidentally energized."

Another reason DES chose DC steel poles was to reduce the amount of long-term maintenance on the line. DES has experienced a lot of wood pole damage from woodpeckers in this part of the county, so that made steel a logical choice. Woodpecker damage has been severe, requiring frequent replacement of wood poles and interruption of service. Also, protection methods for wood poles are costly.

In addition to low maintenance, the weathering steel DC poles were also chosen for their aesthetic appeal. "The line route is in a heavily travelled area," says Smith. "Future expansion calls for a large civic center, and we wanted something that would look nice as the area becomes more built up."

Construction was accomplished by DES employees using normal maintenance trucks. The only unusual piece of equipment was a magnetic base drill. DES does

all the drilling on-site. That way, they can stockpile standard DC steel poles and drill them for a variety of framing applications in the field, says Smith. "Erecting a steel pole line is essentially equivalent to wood. In fact, they are much lighter and easier to handle," he concludes.

Steel poles can also be used for special applications. Inside the development park, a DC steel pole was used to support a cluster of three transformers that serve a large building. "Our experience with DC steel poles has been very good, and we plan to use more of them in the future," says Smith.

Meyer Distribution ClassSteel Poles Supply PowerTo Growing County Complex

Robert A. Smith Vice President, Engineering &

Construction

Case Study No. 14

"ONLY STEEL POLES WOULD

ALLOW US TO CARRY THIS LOAD AND STILL MAINTAIN

OUR DESIRED SPAN OF UP

TO 250 FEET."


HOME

Like many growing cities, Austin, TX, has been expanding its local highway system, creating a large

number of distribution line relocation projects for the City of Austin Electric Utility Department (EUD). One recent project involved the widening of Highway 183 west of interstate 35 through a large commercial area.

The existing line was a 12.5 kV three-phase, wood pole, distribution line with 795AA conductors. With the highway widening, the new ROW was severely restricted, and commercial land owners were reluctant to allow guyed structures to be used for the numerous light angles. In previous projects, the EUD had used a three pole configuration consisting of two deadend wood poles with one middle wood pole at the turn point. But, on this line, a different solution needed to be found for the light angles.

DESIGN GUIDELINES

With a restricted ROW, plus a need to clear existing 40-foot lighting standards, the EUD set the following criteria for selecting structures.

• Poles must be simple to install using standard equipment.

• Compatible with standard hardware.

• Rapid delivery to meet schedules.

• Blend with existing wood structures.

• Able to withstand angles of 3° to 10° without guys.

The EUD was familiar with galvanized steel poles, and had used them with excellent results on a number of transmission lines. However, the EUD was concerned with the cost of these poles and the necessary lead time for delivery. In addition, galvanized poles would not blend in well with existing wood poles.

A solution suggested by the engineer of the City of Austin was to use weathering steel poles that could withstand the angles. Thomas & Betts supplied the Meyer LD steel poles that met all the criteria of the design guidelines. Plus they represented a major cost savings over the three-pole wood angle configuration.

INSTALLATION

At first, EUD construction crews were skeptical about the use of steel poles in a distribution line. However, once crews experienced the ease of installation and the time saved in the construction of the line, they have begun to suggest additional uses for steel poles in the EUD overhead distribution system.

When EUD compared the cost of installing one 60-foot LD steel pole vs. a three-pole wood turning configuration, EUD found the labor and material savings with steel poles to be approximately $3,000 per structure. This represented a savings of about $90,000 on the entire project using steel.

As a result of EUD's experience with steel poles, they now have a standard supply agreement with Thomas & Betts to expedite future steel pole purchases.

Jerry FaselSupervisor,Overhead

Coordination Section

Meyer LD Steel Poles SolveDistribution Line Problems

Case Study No. 15

"LABOR AND MATERIAL

SAVINGS WITHSTEEL POLES

WEREAPPROXIMATELY

$3,000 PER STRUCTURE."


HOME

When Tarboro, NC built a new substation, it faced a series of difficult problems. According

to Electrical Superintendent, David Briley, the issues were construction deadlines, ROW restrictions, aesthetics, cost, structure strength and line reliability.

"Two lines, each carrying three, 15 kV distribution circuits (nine phases) were coming out of this substation as part of a new distribution loop," says Briley. "Since these circuits needed to supply a large and growing area of the city, the conductors and neutrals were a heavy 795 Arbutus 37-strand AAC. That meant that the poles needed to be extra strong to withstand the unusually heavy loading."

Both lines cross under existing 230 kV and 115 kV lines belonging to North Carolina Power that were feeding the new substation. In addition, construction was taking place on a site where the town was building a new Municipal Service Center. This limited the available ROW and, since the site was public, raised concerns about aesthetics.

Reliability was also a concern of Briley's. Just five years ago, Tarboro replaced 360 yellow pine and fir wood poles that were deteriorating after only two years. Although experience with wood distribution poles has been satisfactory, the warm, wet climate takes its toll. Concrete has held up well, Briley said, but concrete was ruled out because of the heavier equipment needed for installation.

THE SOLUTION WAS LD STEEL

The town chose Meyer LD steel poles from Thomas & Betts. Steel poles offered the load-carrying strength, ROW aesthetics, low maintenance and high reliability. "In addition," says Briley, "standardized LD steel poles allowed us to design and construct the

line ourselves, using small crews and our own equipment. That saved us a lot of money.” Because the substation and the Municipal Service Center were constructed close to the transmission lines, there were many design changes. "This forced us to delay the final design of the lines until the last minute," says Briley. "In the end, we had very little time to order and take delivery on poles and still make our in-service

date."

In November, 1994, Tarboro ordered 24 Meyer LD steel poles ranging in length from 35 to 65 feet. Within six weeks, the poles were manufactured in Thomas & Betts' Houston facility and delivered to Tarboro on a single truck. A four-man crew with a 5 ton digger/derrick truck handled the entire installation. "Although this was our first project with steel, the only new piece of equipment we

needed was a Milwaukee magnetic drill. Construction was straightforward and completed on schedule.” Sandy clay allowed direct embedment and a ruling span of 300 feet. Poles were treated with Corrocote polyurethane coating and holes back-filled with 3/4" aggregate. Every pole was grounded with a driven ground rod connected to a NEMA stainless steel ground pad. Braceless Apitong wood cross arms were used. Due to the heavy loads, transmission-size guys and anchors were used. Even with guys, the lines required only 30 feet of ROW – about half of that required for equivalent-strength wood H-frames.

After this first experience with LD steel poles, Briley sees more uses for steel in Tarboro. "In the future, we intend to stock and use steel in locations where maintenance or pole change-out is a problem."

David BrileyElectrical

SuperintendentTarboro,NC

Town Solves Complex Problems With First LD Steel Project

Case Study No. 16

"STANDARDIZED LD STEEL POLES

ALLOWED US TO DESIGN AND

CONSTRUCT THE LINE OURSELVES,

USING SMALL CREWS AND OUR OWN

EQUIPMENT."


HOME

When the 40-year-old transmission line between Cinergy substations at

Greentown and Wabash needed upgrading, project engineer Bob Koehler decided to perform a 50 year, life cycle cost analysis of wood and steel pole structures. The results showed that replacing the time worn wood H-frames with Meyer LD Steel H-frames would be more cost effective.

"We took into consideration the initial costs (material and labor) and all future maintenance costs," Koehler said. "The lower, life-cycle maintenance cost of LD steel poles more than made up for the higher initial

costs, and steel came out slightly less expensive than wood."

Although Cinergy had used steel pole structures for several years, the three-phase Greentown-Wabash line was the company's first project involving 138 kV steel H-frames. The 23 mile line crosses relatively flat terrain. The line design was based on tangent H-frames with spans of 700 to 1,000 feet and were equivalent to wood H-frames utilizing Class 2 and Class 3 legs. The project involved 170 weathering steel tangent H-frames, and 25 weathering steel guyed three pole angles and dead-end structures. Normal embeddment depths with select aggregate backfill was used.

To provide for increasing power

demands, each structure supports three 954 ASCR conductors and two 3/8 in. EHS static wires, replacing the original 397 ASCR conductors. The poles were set at an average depth of nine feet with ruling spans of 700 to 1,000 feet.

Using steel poles eliminates damage caused by woodpeckers and groundline rot, which in turn further reduces maintenance and

replacement costs. By eliminating these elements of nature, Cinergy will also be able to minimize the frequency of service interruptions.

Since steel is considerably lighter than wood, Koehler said that contract crews found the Meyer LD H-frame steel poles exceptionally easy to work

with. He said that workers were able to construct a record fifteen miles of line in a three-month time span.

"The LD H-frames required only 10 bolts per structure to assemble, compared to approximately 40 bolts for wood structures," he continued. "When working with wood poles, our construction crew could only frame about two to three structures a day. Putting up the steel H-frames was much easier for them. They were very happy to be able to frame eight to ten steel structures a day, once they really got going."

The advantages of steel over wood, combined with favorable life cycle cost analysis, have encouraged Cinergy to consider steel for future projects involving rebuilds and new construction.

Bob KoehlerProject EngineerCinergyPlainfield, Indiana

Meyer LD H-frame:Cost Effective Alternative

Case Study No. 17

"THE LOWER, LIFE CYCLE MAINTENANCE

COST OF LD STEEL POLES MORE THAN MADE UP FOR THE

HIGHER INITIAL COSTS, AND STEEL

CAME OUT SLIGHTLY LESS EXPENSIVE

THAN WOOD."


HOME

Meyer LD steel poles from Thomas & Betts were the logical choice for Nantahala Power and

Light when the utility planned to construct a transmission line from its Lake Emory substation in Franklin to service a rapidly growing section of its territory near the Great Smoky Mountains National Park – a tourist area that accommodates eight to nine million visitors annually.

Historically, Nantahala has relied primarily on wood poles for transmission lines. However, after researching the advantages of steel, Doyle Ridley, transmission and distribution staff assistant, recommended Meyer LD-6 steel poles for this project. Doyle, who designed the new line, said that construction deadlines, aesthetics, size and strength all came into play in Nantahala's decision to use galvanized steel poles instead of wood.

"Our construction schedule did not allow time to wait the six to nine months that it usually takes for us to get wood poles. The steel poles could be delivered in a matter of weeks, allowing us to keep the job on schedule," says Ridley. "For ease of construction, we also planned to stack the 3/8 inch EHS static wire and six 795, (26/7) ACSR conductors vertically on each pole with a 12-foot spacing between them. It takes a very tall pole to do that. We simply couldn't get wood poles in the lengths we needed."

Nantahala was able to order the 32 LD steel poles needed for the first phase ofthe two-phase project in 120-foot lengths to accommodate the vertical conductors. The new double circuit transmission line consists

of two 161 kV lines coming into the station and four 69 kV lines leaving it. With an ultimate capacity at ground line moment at 704 foot-kips, Nantahala was assured that the extra tall Meyer LD steel poles would have the strength to carry the heavy duty lines. "It would have been almost impossible to get the strength in wood that we were able to get in the LD-6 poles," said Ridley.

Since the substation that provides power to the new line was also constructed of galvanized steel, the LD poles blended well aesthetically. And Ridley points out

that Nantahala's construction crew was impressed with how easy the steel poles were to erect. "They are lightweight and, unlike wood, are perfectly symmetrical. We drilled them on site and found they drilled the same as wood," he said.

Most of the poles were set at ruling spans of 429 feet, with two of them at spans of 737 feet in order to stretch across the Little Tennessee River from two mountain tops. The first phase of the project, incorporating one and a half miles of tie line connecting to a line that loops around the town of Franklin, is complete. Nantahala plans to construct an additional four miles of line. Ridley estimates that it will take an additional 60 to 70 LD steel poles to complete the project and Nantahala has contracted with Thomas & Betts to order the poles once the design is complete.

According to Ridley, discovering the many advantages of steel poles has motivated Nantahala staff to "take a hard look" at using them for all future transmission line construction.

Doyle RidleyTransmission and

Distribution Staff Assistant

Nantahala Light and Power Company

Franklin, North Carolina

Delivery Key To Selecting Steel Poles For Nantahala Project

Case Study No. 18

"THE STEEL POLES COULD BE DELIVERED IN A

MATTER OF WEEKS, ALLOWING US TO KEEP THE JOB ON

SCHEDULE."


HOME

Until recently, when a wood distribution pole in the City of Memphis failed due to groundline

rot or was damaged by traffic, the pole had to be replaced. This required maintenance crews from the Memphis Light, Gas & Water Division (MLG&W) to work long hours. In many cases, this included premium pay hours to repair the pole and transfer transformers, switches, street lights, lines and all the associated hardware to the new pole. In addition, the other utility companies (CATV, telephone) had to transfer their facilities – all at considerable cost.

Now when they have a damaged wood pole, it is often repaired in a fraction of the time of replacement with an ingenious pole splice called an LD Quick SpliceTM manufactured for MLG&W by Thomas & Betts. The product saves time, labor, money, improves customer service, and frees up crews for other tasks.

DESIGNED TO SAVE TIME, MONEY

The concept for the LD Quick Splice was developed by MLG&W Systems Engineer, E.C. "Jack" Richey, who was trying to come up with a way to speed up replacements of broken wood poles and eliminate crews spending a lot of time changing out damaged or broken poles. "We tried to come up with an alternative solution," says Richey. "There have been other products for repairing a cracked or broken pole, but because of their design, they were difficult to install and had limited pass-through strength. What was needed was a workable splice that was easy to install and provided the strength of the original pole."

The LD Quick Splice accomplishes both. It consists of a steel pylon to replace the damaged portion of the pole, and two, 44-inch split-sleeves that connect to the undamaged top of the pole. The device is made of weathering steel, which Richey says blends aesthetically with the existing wood poles. The below ground portion of the pylon has an epoxyurethane coating to provide corrosion protection, and there are

provisions for grounding through the pylon. Thomas & Betts performed the original strength analysis on the LD Quick Splice and optimized the use of steel. MLG&W now stocks the repair pylons in two lengths with two different sleeve diameters to accommodate the most common wood pole classes in their system.

"The first time one of our crews used the splice, a car had hit a pole and broken it about three feet above the ground. Using the LD Quick Splice, the pole was repaired in 45 minutes. This compared to an estimated 12 hours of time required to change out this pole at a direct crew cost of $300 per hour," says Richey The splice is more expensive than a wood pole, he says, but the savings in labor far outweigh the extra material expense.

TWO TYPES OF BREAKS

"We have two common instances of pole breaks that call for this splicing technique," says Richey. "When the pole failure is due to ground-line rot, the damaged area rarely goes higher than 18 inches above the ground. The rest of the pole may be fine. The other common splicing situation results from traffic accidents, where the break may be from the ground to about 12 feet off the ground."

There are two sizes of LD Quick Splice which accommodate most common repair situations. A nine-foot pylon allows for six feet below grade with a transition to the wood pole at about three feet above the ground. This size is used for groundline rot repairs and many car-damaged poles. The other size uses an 18-foot pylon. These two sizes accommodate the majority of wood poles used in the MLG&W system.

Since many breaks occur below the neutral with the rest of the pole remaining sound, this procedure is able to salvage many poles. If a pole breaks and the fracture runs too high, then it must be replaced. Crews must examine the entire pole and make a determination that it's worth saving.

LD Quick SpliceTM Yields Big Savings ForMemphis Light, Gas & Water

Case Study No. 19

"USING THE LD QUICK

SPLICE SAVED UP

TO12 CREW

HOURS OF LABOR AT A COST OF $300 PER

HOUR"


HOME

INSTALLATION IS QUICK, EASY

Installation of the LD Quick Splice is straight-forward, and crews have adapted rapidly with minimal training. First, any damaged pole must be inspected to see if it's worth splicing or whether it needs to be completely replaced. Some poles, like single phase tangent structures, are easier to change out and will be replaced rather than spliced. But poles supporting multiple phases, transformers, switches, underground risers, and communications cables, are most often good candidates for repair.

With a pole line truck or simple A-frame supporting the top half of the pole, the pole is cut off square at the proper height with a chain saw. Usually, another pole line truck removes the butt end of the damaged wood pole. Then, the steel pylon with one of the half-shells of the coupling installed, is set in the original hole. The other half-shell is maneuvered into place and both halves are bolted together, sandwiching the wood pole in the splice. In restricted right-of-way areas where it's not possible to use two line trucks, the job can be done with only one.

Once the split shells are secured, the space between the wood pole and the shells is filled with a high-density urethane foam. This high-strength expanding foam quickly sets up to form a permanent bond between the wood pole and the steel coupling. Where the urethane foam is exposed to sunlight, it is sprayed with a brown enamel to prevent UV light from affecting the material.

"In about 15 minutes, the urethane foam attains 75% of its maximum strength, and the support can be taken away." The result is a repaired pole that is as strong as the original, he says.

The concept of the LD Quick Splice has been so successful that Richey was granted a patent in 1994 by the U.S. Patent Office. Richey says MLG&W employees are encouraged to innovate solutions and submit ideas for patents as a way to foster excellence within the department.

SPLICES ARE RETRIEVABLE, REUSABLE

Richey believes the splices are retrievable and reusable when a repaired pole eventually has to be completely replaced. Although none of the splices have been recycled yet, they are designed to be used again. One likely situation would be during a road-widening where a spliced pole would have to be moved. The LD Quick Splice could be removed, sand-blasted to remove the urethane, and re-used at another site.

The City of Memphis has installed approximately 30 LD Quick Splices over the past two years, and line crews have come to like them because they not only reduce labor, but they also prevent recurring breaks at that same location due to traffic mishaps." Poles have survived a lot of scrapes without further damage," says Richey.


Split shells are brought together around the cut off wood pole.

High-density urethane foam fills the cavity and secures the pole.

As

David JamesTransmission

Design EngineerWashington Water

Power CompanySpokane, WA

LD Poles Chosen Over Wood In 115 kV Reconstruction

Case Study No. 20


As part of an overall project to improve electric service

reliability in the vicinity of Coeur d' Alene, Idaho, Washington Water Power recently reconstructed an existing 115 kV transmission line called the Appleway Tap. Built on wood H-frames in the 1930s, the existing single-circuit line still had its original conductors of 250 KCM copper. Due to residential and commercial load growth, the transmission system could not reliably serve all customers under conditions of peak electrical demand.

In order to reinforce the transmission system, Washington Water Power decided to replace the existing single-circuit line with a double-circuit line. The existing circuit would connect through a new switching station along the route, and the new circuit would provide a second source for the Appleway Sub.

"In order to minimize land use along the right-of-way, we chose to utilize the single pole design instead of the traditional wood H-frame," says David James, Transmission Design Engineer for Washington Water Power Company. "Wood poles large enough to support long spans of double circuit line were expensive and hard to find. With these constraints, we found that Meyer LD steel poles were cost competitive, and offered other advantages."

James says that among these other advantages were steel's higher strength and

reliability, as well as uniformity and aesthetics. And, while the initial cost of steel was slightly higher than wood poles of the same rating, James has calculated that higher reliability factors and lower maintenance will result in a significantly lower life cycle cost.

All of the LD poles along the three-mile project were LD-3 through LD-6 tangent structures made of weathering steel. Spans ranged from 400 to 650 feet, and the conductors were a combination of all-aluminum 795 Arbutus and 556 Dahlia. The phases were arranged vertically on polymer horizontal post insulators.

The construction of the line was accomplished with a five-person crew, a crane and a boom truck. The poles were pre-drilled by the supplier for quick field assembly, and at less than half the weight of a comparable wood pole, LDs were easy to install, he says.

The buried portion of the LD poles are treated with a urethane mastic. "We've had some experience with mastic compounds, and Corrocote II is more resilient against damage when backfilling with crushed rock, and this helps to prevent future maintenance problems."

The utility's experience has convinced them that LD steel poles offer advantages over wood products. "Washington Water Power will continue to consider LD poles for new construction and as replacement products for wood poles," James concludes.

MEYER LD ADVANTAGES

• Light weight • High strength • Low long-term costs

• Easy installation • Longer spans • Aesthetic appearance

• Low maintenance

"MEYER LD POLES

WERE COST COMPETITIVE, AND OFFERED

OTHER ADVANTAGES."

HOME

While the country was looking forward to fireworks displays for the upcoming Fourth of July

holiday in 1997, 60 miles southwest of Wichita, KS, Mother Nature was preparing some fireworks of her own. On the evening of June 29th, a wall of thunderstorms and tornadoes crossed Western Resources' 345 kV transmission line that linked Wichita with the Woodring Substation in Oklahoma, a facility owned by Oklahoma Gas & Electric (OG&E).

The 345 kV wood H-frame line had been built in 1967 and is a straight, north-south, line consisting entirely of two-pole tangent H-frame structures with no deadends. When the thunderstorms and tornadoes struck, only a few structures fell. But the resulting longitudinal imbalance started a cascading failure that traveled for 33 miles, destroying a total of 239 wood H-frame structures.

While the damage struck during a 4,500 megawatt annual peak demand period, none of our customers experienced power outages. Rural electric cooperative customers did experience outages, however, when our unbroken conductors and shield wires dropped onto local cooperative distribution lines running along east-west roads. Our 345 kV intertie with OG&E was critical to overall reliability in the region, and each day the line was out of service would be costing Western Resources thousands in lost revenue. Getting the line back into service was, therefore, a very high priority.

DISASTER TEAM TAKES ACTION

Immediately, our disaster team sprang into action, assessing the extent of the damage and clearing lines that had fallen across railways and highways – a task that was completed by the end of the first day. Then, we quickly began the process of designing the replacement structures and deciding about structure material.Material availability, time, costs and ease of erection were all important considerations in designing the replacement structures. The material options we reviewed included:

Laminated wood poles – As an engineered product, laminated wood poles were an attractive option, initially, because delivery time looked good. But initial costs were more than 40% higher than other material options, and this option was quickly eliminated based on cost.

Wood poles – As a direct replacement of the existing structures, this option would have required the least design time, however, local availability was poor and costs were also high.

Concrete poles – This option was briefly considered, but soon eliminated due to availability, cost, and other issues.

Steel poles – We found that Meyer LD H-frame structures from Thomas & Betts could be delivered quickly and at the lowest installed price of any of the pole options. In addition, there were advantages to be gained due to their simple construction. easy erection and light weight compared to the other options.

ADVANTAGES OF STEEL

Steel H-frame structures were selected based both on initial cost and timely delivery. In fact, recent experience at Western Resources has shown there are additional advantages with steel poles. For example, as an engineered product, steel poles perform more predictably than natural wood poles. Steel is also a forgiving material, with inherent strength and toughness that often exceed practical design limits. When made of weathering steel, steel poles have other advantages, including: 1) it looks like wood; 2) offers savings on finishes; 3) requires less maintenance; and 4) it has great aesthetics for a cross-country line application.

Allen Ackland, Manager

Electric Transmission

Line Engineering Western Resources Topeka, Kansas

Steel H-Frames Save Time, Costs, Rebuilding Line

Case Study No. 21


Over the course of the reconstruction, crews assembled and installed an average of 18 steel H-frame structures per day.

HOME

The Meyer LD H-frames we selected were direct equivalents for H-1 wood poles, which also simplified the redesign. However, at about half the weight of wood, steel poles would be easier to install with smaller crews and normal equipment. The steel H-frame structure consisted of only seven parts and nine bolts, which meant that field assembly would be faster than traditional wood pole H-frames.

An additional advantage of steel was the elimination of ground sleeves and climbing ladders saving $200,000.

Since the lack of deadend structures may have contributed to making the cascading failure much worse, two new three-pole deadend structures were designed into the new line. In addition, 23 other steel deadend structures were ordered from Thomas & Betts to be installed on the nearly 1,000 miles of Western Resource's 345 kV transmission lines.

Although the steel H-frames would have permitted a new line with fewer total structures and slightly longer spans than the original 600-700 feet average, we decided to simply replace the line on a structure-for-structure basis. As a result, selection of the materials and the redesign of the line were completed and put out for bid just four days after the outage. Thomas & Betts was awarded the contract and we ordered the poles on the tenth day.

RECONSTRUCTION

Steel poles from Thomas & Betts' Houston manufacturing facility began arriving just 25 days after the order was placed. Delivery of the poles began at the southern end of the damaged line and was coordinated with the progress of the installation crews as they moved northward.

Although the construction crews were more familiar with wood pole H-frames, the assembly and erection of the steel H-frames proceeded efficiently. Each pole was manufactured and shipped in two parts, so the crews first used a hydraulic jack,

developed especially for these steel poles, to assemble the slip joints. We elected to bolt longitudinal straps called slip joint keepers across the joint to prevent the possibility of the poles coming apart under transverse stresses such as high wind loading.

Next, the crossbar was bolted into place, and the assembled H-frame was lifted into place by a crane. One of the big advantages of the steel H-frames is their low weight – nearly one half the weight of comparable wood H-frames. This meant that the line could be rebuilt with small crews and readily available equipment. Over the course of the reconstruction, crews assembled and installed an average of 18 steel H-frame structures per day.

Just as with the original wood H-frames, the steel H-frames were direct buried. A typical steel H-frame structure was85' with 10% plus 2 feet below grade. Holes were augered near the original pole placements, the structures were hoisted into position and the holes were backfilled with gravel. To prevent corrosion, the below grade portion of the steel poles was coated with Madison Chemicals' Corrocote II Classic, a polyurethane coating.

CONCLUSION

Construction of the rebuild was completed 67 days after the arrival of the first of 486 steel poles and crossarms for the 241 H-frame structures – all told, more than two million pounds of fabricated steel. Our experience with steel poles had been good on the Western Resources system, and this reconstruction project showed that not only can rebuilding with steel H-frames be a fast solution under the pressure of a major outage, but it can often be the lowest cost solution as well. And, the added integrity of steel ensures that there will be fewer outages of this type on the Western Resources system in the future.


A total of 239 wood frame structures were destroyed in the storm.

Avista Corporation, a Fortune 500 company with annual revenues of more than $5 billion, is a

diversified energy company with utility and subsidiary operations located throughout North America.

In the utility's rural eastern Washington service area, a steady increase in demand made it necessary to convert a 115kV switching station into a 115/230kV substation.

A COMMITMENT TO LANDOWNERS: NO NEW STRUCTURE LOCATIONS

The biggest challenge of the project came in Avista's plans to upgrade the line that would deliver the 230kV power to the substation.

The 26.5-mile H-frame line ran primarily through prime farmland-rolling fields of wheat and grass seed. In consideration to the farmers, Avista committed to utilizing only existing structure locations for the upgrade.

This commitment presented a significant challenge. Avista's 230kV design parameters call for a minimum conductor size of 1272 KCM with NESC heavy-wind and ice loading. In addition, the land's farming usage required a minimum ground clearance of 30 feet and a maximum operating temperature of 176F (80C). The ruling spans ranged from 700 to 1,100 feet.

Avista's original plans called for ACSR conductor tensioned at 40 percent of its ultimate strength to minimize sag. The new tension level necessitated two dog-bone vibration dampers in each span. The utility planned to replace the existing wood H-frames with new H-frames. And, as promised, they would add no new locations.

To compensate for the new levels of weight and tension, nearly half of the ANSI-Class I and 2 wood poles would have to be more than 75 feet long, with the longest being 100 feet.

And to compensate for the poor lateral support given by the clay-rich soil during wet conditions, the utility decided to X-brace the H-frames.

There were still challenges, however. Pole weight, for example, was a major concern. It looked like it would be necessary to ferry in a sky crane to erect the heavy longer poles on the steep hillsides. The utility also hoped to find a way to offer improved fire protection for the poles, because many area farmers burn field stubble in the fall.

THE IDEAL ANSWER: LD STEEL

The utility considered light duty steel for its smaller weight-to-strength ratio, which would allow for helicopter erections. In addition, the steel is fire-proof.

Of further benefit, cost-analysis revealed a much lower lifetime ownership cost for the durable steel structures. (Limited access to many of the structures made ongoing ground-line decay inspections of wood poles exceedingly expensive.)

But the utility expected steel to be significantly more expensive in up-front costs. Surprisingly, the long pole lengths required by the job made the steel costs and wood costs roughly the same.

The added construction efficiencies, fire safety, and long-term maintenance savings made steel more cost-efficient than wood.

Avista chose rustic-looking, self-weathering Meyer LD H-frames from Thomas & Betts and utilized two sizes of tubular-steel cross-arms.

Line construction and helicopter erections went very smoothly and costs were within budget. Avista is delivering more power – and more customer satisfaction – thanks, to the Thomas & Betts alternative, Meyer LD H-frames.

Art Shawen, PE Transmission Design

EngineerAvista Corp. Spokane, WA

Avista Puts LD to the Test in Tough Rural Washington Upgrade

Case Study No. 22

CONDUCTOR UPGRADE:

250 copper to 1272 KCM

ADDITIONAL STRUCTURE

SITES ALLOWED: 0

MINIMUM GROUND

CLEARANCE: 30 feet

ACCESS: extremely limited

CONDUCTOR TENSION:

40 % of ultimate strength

STRUCTURE CHOICE:

Meyer LD steel X- braced

H-frames


HOME

Manitoba Hydro is a Crown Corporation, owned by Canada's Province of Manitoba. Responsible

for the energy requirements of most of the province, the utility is the fourth largest in Canada and today has assets of more than $7 billion. Manitoba Hydro operates 14 generating stations – 12 hydroelectric and two thermal.

These stations deliver to Manitoba residents a steady supply of power that is 99 percent generated by water energy. The self-renewing resource has driven the prosperity of the region, and continues to fuel the area's success. Electricity rates remain, overall, the lowest in Canada, and the utility generates extra income for the region by exporting surplus power.

Transmission technology plays a big part in the export business of Manitoba Hydro. Today, the benefits of hydroelectric power aren't just available to customers who live near rivers. Advancements in transmission technology over the past fifty years have contributed to Manitoba Hydro's success, and the utility is still known for its ongoing commitment to the latest in advanced transmission lines and structures.

So when it came time to erect the $40-million Winnipeg-to-Brandon line, Manitoba Hydro considered all of its structure options. The original proposal was to have the majority of the transmission line strung on traditional red- cedar wood Gulfport structures, with about one third of the line on steel lattice towers. The Gulfport structures were replaced with Meyer LD H-frame structures from Thomas & Betts after a cost-comparison study.

The choice resulted in substantial project cost savings, and is also yielding some significant new ongoing efficiencies.

LONG TRANSMISSION DISTANCES

PUT PRESSURE ON LINE COSTS

Manitoba Hydro's transmission system is characterized by long lines. In fact, there are an estimated 70,000 kilometers of transmission and distribution lines in the utility's systems ...enough to circle the earth twice.

The new Winnipeg-to-Brandon line was slated to be a 230-kV line that began at the Dorsey

converter station in Rosser, traveled by the town of Neepawa, and terminated at the Cornwallis station in Brandon. Rosser is one of the major hubs of Manitoba Hydro's transmission and distribution network, and serves as a termination point for the extra-high-voltage DC transmission lines that bring power down from the generation stations on the Nelson River in the northern part of the province. The new more- than 200-kilometer line was needed to serve the growing demand in both the Neepawa area and in Manitoba's southwest region.

The utility started planning for the Dorsey- Cornwallis line back in 1993. Manitoba Hydro's commitment to its neighbors and the environment plays a big role in routing and engineering decisions, and the utility started this new project with community education, an environmental impact study, and a regulatory procedure called Site Selection and Environmental Assessment.

The utility's commitment to ratepayers is equally important. Manitoba Hydro's long transmission and distribution lines are supported by more than 600,000 utility structures. Even the smallest savings in pole costs pay big dividends over time.

So, for the Dorsey-Cornwallis project, Manitoba Hydro began to investigate cost effective alternatives to the traditional Gulfport structures it used on most projects. These western red cedar wooden poles typically were 65 to 85 feet in height and weighed about 8,500 pounds. Manitoba Hydro observed ruling spans of 265 meters and setting depths of 10 percent-plus-two.

STEEL POLES RISE TO THE CHALLENGE

A recent project had proven that steel tubular structures can deliver big savings. In 1998, Manitoba Hydro was planning to build 215 kilometers of utility structures carrying 138-kV transmission line. The critical line serves nine communities northeast of Winnipeg. Initial plans called for the use of the western red cedar pole structures, but a cost-comparison study prompted engineers to specify tubular steel guyed Y-structures, instead.

Ben S. Yue, P.E. Transmission

Engineering Section Head

Manitoba Hydro Winnipeg, Manitoba

Manitoba Hydro Turns to LD for Lower Costs and Improved Longevity in New Line

Case Study No. 23

“MANITOBA HYDRO’S TRANSMISSION SYSTEM

IS CHARACTERIZED BY LONG LINES. IN

FACT, THERE ARE AN ESTIMATED 70,000 KILOMETERS OF

TRANSMISSION AND DISTRIBUTION LINES

IN THE UTILITY’S SYSTEMS...ENOUGH

TO CIRCLE THE EARTH TWICE.”


HOME

On average, opting for steel had reduced the project's cost by roughly $4,000 per kilometer. In addition, steel offers an exceptionally wide range of aesthetics and performance within project parameters, and has a strength-to-weight ratio well above most materials. Steel also requires minimal maintenance, and offers design options that are unavailable in wood or concrete. For the Manitoba Hydro North Central project, the higher price of wood and the longer spans possible with steel had made the decision an easy one.

So when plans were under way for the new 230-kV Dorsey-Cornwallis line, engineers took a good look at steel. Once again, steel structures proved more cost efficient. Manitoba Hydro opted for Thomas & Betts Meyer LD Steel H-frames.

Engineers worked with Thomas & Betts personnel in Memphis, Tennessee, and Hager City, Wisconsin, to develop the most cost effective structure. Thomas & Betts – a single-source company that provides lattice, custom, or standard tubular steel structures in H-frame or single-pole configurations – delivered structures with about the same height, setting depths, and ruling spans of the wood structures. The weights, however, were significantly less and the costs were markedly lower.

In addition, the ready availability of the structures provided an advantage over wood. Scarce supplies of western red cedar poles can slow a project timetable. The steel structures were more durable and offered higher longitudinal strength. Their flexibility also contributed to better line optimization.A full-scale structure test to design limits

was performed. The results supported Manitoba Hydro's decision to use Meyer LD H- frames. In addition to the design loads, a longitudinal load was applied until the arm/connection had permanent set. This further substantiated their decision. The structure provides a higher level of reliability to the transmission system.

Additional benefits realized during construction were the result of the simplicity of the structure. The Meyer LD H-frame was made up of five components and nine bolts. This allowed a setting crew of three to assemble 25 structures per day and erect up to 10 structures per day. Reduced construction time results in more cost savings.

Also important was the impact on long-term ownership. Weathering steel offered Manitoba Hydro substantially lower maintenance expenses.

Utilities all over the world are facing mounting budget pressures. In addition to fewer dollars for projects, they also have a long list of new demands. Environmental concerns and shorter project timetables contribute more pressure to transmission and distribution projects. LD steel is fast emerging as a preferable alternative to wood utility structures because of their versatility and fast erection windows. Today, LD steel provides a significant cost advantage, as well, making it a strong choice for a number of demanding applications.


Wood-to-Steel Installation Cost Comparison (Canadian dollars, based on a typical 85-foot pole length structure)

WOOD STEEL

STRUCTURE TYPE: Gulfport Meyer H-frame

PURCHASE PRICE $ 9,138 $ 8,398 (per structure)

HARDWARE COSTS $ 1,046 $ 665 (per structure)

INSULATOR COSTS $ 1,028 $ 1,028 (per structure)

ERECTION COSTS $ 2,460 $ 1,900 (per structure)

TOTAL COST $13,672 $11,991 (per structure)

MANITOBA HYDRO'S DORSEY-CORNWALLIS PROJECT

Wood-to-Steel Installation Cost Comparison (Canadian dollars)

WOOD STEEL

STRUCTURE TYPE: Gulfport Guyed-Y

MATERIALS COST $31,182 $30,778 (per kilometer)

CONSTRUCTION COST $64,463 $60,845 (per kilometer)

FIXED COSTS $31,268 $31,268 (per kilometer)

TOTAL COST $126,913 $122,891 (per kilometer)

MANITOBA HYDRO'S NORTH CENTRAL PROJECT

Since the beginning of the '90s, Kelowna, BC, has been one of Canada's fastest growing cities.

To meet load-growth in the area, West Kootenay Power needed to upgrade the transmission system on its Winfield-to-Vernon line from 138 kV to 230 kV. The line is in an area that had been built up over time, and some of it had become quite congested. A critical 19-mile section comprised of 132 wood structures in mixed H-frame and single-pole sections had to be rebuilt.

A portion of the line traversed Kalamalka Lake Park, a sensitive provincial wilderness area. Engineers had three choices for the new structures: wood, steel or concrete. "Because some locations are difficult to access at certain times of the year, we wanted a material we didn't have to check on a regular basis," says Murray Detmold, P. Eng., Transmission Designer for West Kootenay Power. "Concrete was deemed too heavy and not readily available. Wood rots and is subject to damage from animals. We selected steel for its durability, light weight, and relative imperviousness to the elements. Steel poles are also more aesthetically pleasing than wood or concrete and, if replaced for some reason, can be recycled."

SEVERAL BIDDERS

West Kootenay Power requested quotations from several steel-pole suppliers. Each was asked to bid on the design and fabrication of poles in accordance with specific design and loading criteria. Thomas & Betts was successful, supplying the poles and the arms for the project. Weathering steel was chosen for its protection effectiveness as well as its color, which blends in nicely

with the landscape."As the project got underway, Thomas & Betts was timely in providing us with the necessary approval drawings," says Mr. Detmold. "Early on, a project schedule was established that we could work with and they consistently met the dates specified. Because they couldn't get the guarantees they required from the railway, they arranged to have the poles trucked in. They were a great bunch of people to work with and went out of their way on more than one occasion to deliver after hours and in out-of- the-way locations."

THE RIGHT CHOICE

Construction of the Winfield-to-Vernon line upgrade began in the summer of 1996. The plan was to complete the project before the end of that year, but weather conditions delayed stringing about four miles of the line until the spring of 1997. A typical span in the new line runs from 800 to 1000 feet. with some spans reaching as much as 3000 feet.

Says Murray Detmold: "We're now using steel poles more and more, especially in areas like this where wood may not last, accessibility is an issue and/or aesthetics are critical. Without question, I feel that we made the right choice."

West Kootenay Power Trail

British Columbia

STEEL CONQUERS KELOWNAWest Kootenay Power Chooses Steel Poles for Power Upgrade

Case Study No. 24

VOLTAGE UPGRADE: 138 kV to 230 kV

CONDUCT0R UPGRADE: 397 kcmil ACSR to 795 kcmil ACSR

ADDITIONAL RIGHT-OF-WAY: None due to settlement buildup

SENSITIVE AREAS: Provincial wilderness and residential areas


HOME

In the early '90's, the City of Saskatoon faced upgrading its 72 kV transmission line on wood poles with a new 138

kV line. The deteriorating 30-year old wood poles needed replacing. and the city required a higher-voltage line to meet future electrical demands.

The transmission line route forms a ring within the city, feeds six substations, and closes back on itself via a steel tower river- crossing. It comprises some 200 structures in all. To minimize inconvenience, city engineers first divided the project, dubbed the "QE 1-5 Transmission Line Upgrade," into seven sections totaling 26.7-km. Construction was slated to begin in May 1991 and finish in August 2000. The nine- year marathon launching Saskatoon into the new century went exceedingly well, however, and by the end of 1999, all that remained to be done was the steel-tower river crossing.

CONSIDERED ALL THE OPTIONS

Before any work was carried out, city officials and other local authorities gathered preliminary data and held discussions with potential contractors. Due to the generally narrow right-of-way available, engineers specified single poles for the majority of the new structures, all of which had to support one or two shieldwires, a single 138 kV circuit, and a 15 kV underbuilt circuit, including a neutral wire and street lighting where required. Engineers considered guyed structures for some of the high-angle towers (just 6% of the line) and for the rest, looked at wood, lattice and tubular steel poles.

Although steel poles are slightly more expensive than lattice steel masts, they offered the undeniable advantage of very low visual impact – a key consideration in this urban setting. And steel poles could be custom designed, allowing the city to

double the span-length over existing wood poles, thereby reducing hardware and labor costs.

Specifications for the supply of the steel poles were tendered out for each of the seven sections and in all but one, Thomas & Betts was the successful bidder.

City engineers were pleased with how Thomas & Betts helped out with the design of the steel poles. "The experience of the T&B engineering sales and manufacturing team made a big difference for us, especially in working out the hardware attachment details and the exterior paint finish," says Rob Chan, Saskatoon's senior design engineer. "There's no doubt that their know-how and expertise contributed significantly to the success of the upgrade."

THE LOOK OF A WINNER

Saskatoon opted for painted poles over weathering steel because engineers deemed the cost reasonable given the corrosion protection it provided. They also liked the appearance and color, which nicely blends in to the background and big, prairie sky.

Says Mr. Chan: "The T&B steel poles are aesthetically pleasing and perform well. The poles in the first section were installed seven years ago yet still show no signs of corrosion. That's a big improvement over our old streetlight poles. It looks to us like the new steel poles will give us a lot more than the 30 years we were getting from wood."

Based on its experience, the City of Saskatoon is now considering T&B steel poles for other applications, such as for distribution-line, dead-end poles in situations where there's no room to guy-anchor the pole or to put in an easement for the anchor.

City of Saskatoon, Utility Services

Electrical System Branch

Saskatoon, Saskatchewan

City of Saskatoon successfully upgrades 72 kV Wood Poles with 138 kV Tubular Steel

Case Study No. 25

VOLTAGE UPGRADE: 72 kV to 138kV

ACCESS: Narrow right-of-way,

urban setting

SELECTION CRITERIA: Ability to customize pole design, low visual impact, durability

STRUCTURE CHOICE: T&B tubular steel, painted poles


HOME

On January 31, 2002 a terrible ice storm reduced hundreds of wood H-frame structures to splinters along a 345 KV

line that is a major transmission connection between Westar Energy and its neighbors to the south. The weight of the ice caused the wood structures to fail, leaving system integrity in jeopardy. In 1997, a similar situation presented itself when a tornado flattened hundreds of wood H-frame structures. A 30-mile section was replaced with Thomas & Betts/Meyer steel H-frame structures. The 30-mile section of direct embedded weathering steel 345 KV H-frame structures were still standing after the most recent ice storm.

East of the steel H-frame section in Kansas, (on a different line) another section of wood H-frames which were not replaced in 1997 laid destroyed on the ground under heavy loads of ice. Bob St. John of Westar Energy (formerly Western Resources) knew what to do to restore these down lines in Kansas.

He was familiar with the most cost-effective, timesaving, and long-lasting solution. After all, St. John was a veteran of the 1997 ordeal and had just witnessed the Meyer steel structures on the state’s border withstand the harshest elements.

Bob St. John also knew time was the most critical element in restoring power to hundreds of customers. Relying on his experience from the 1997 storm restoration project he called Thomas & Betts. T&B immediately assembled a team to respond to Westar Energy’s requirements. Together they assessed material requirements using existing drawings, already approved for fabrication. Meyer, with their steel supply partners, devised a fast track response to fabricate and deliver 4 miles of weathering steel H-frame structures in less than 3 weeks without interruption of other customer orders.

“We were confident that Thomas & Betts could deliver on the schedule they promised,” said St. John.

“The Thomas & Betts team was very supportive and they worked hard. Their team worked the weekend before our order was placed to verify the materials were on hand to meet our schedule. We appreciate that kind of commitment and performance by a supplier.”

The order was received on Tuesday, February 5th. By February 25, merely 20 days later, all structures and supporting parts were delivered. Not only was the manufacturing and delivery handled with professional swiftness, but the steel structures themselves were easy to install, compared to wood structures. “They go together quickly,” said St. John, “which means we could be back in service sooner. We went with steel structures because we wanted to restore the line as quickly as possible.”

Most important, steel structures stay up once installed. “There’s no material deterioration with steel. It’s still as strong 40 years from now as when it was originally installed, unlike wood.” added St. John.

Meyer custom designed structures provide cost-effective engineered solutions for carrying high voltage transmission lines. Our steel structures are reliable, easy to install, and can withstand severe conditions. They can be produced on a fast-track schedule, meeting customer requirements to get much needed transmission lines restored in the shortest time possible.

Bob St. JohnDirector of Transmission

Line Engineering & ConstructionWestar Energy PO Box 889 Topeka, KS 66601-0889

Steel Structures Withstand the Harshest Conditions and Can Be Produced More Quickly than Wooden H-Frames.

Case Study No. 26

"WE WENT WITH STEEL

STRUCTURES BECAUSE WE WANTED TO

RESTORE THE LINE AS QUICKLY AS

POSSIBLE."


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