nbridge Technology Inc. (ETI), thetechnology arm of Enbridge Inc., aleader in energy transportation

and distribution in North America andinternationally, recently showcased thelatest tool in its keyhole technologymaintenance and repair arsenal at thefirst annual conference of the GasTechnology Institute held in Orlando, FLfrom Sept. 29 to Oct. 3, 2002—RotaryCoring and Reinstatement.

Developed and field-proven byEnbridge Consumers Gas, one of NorthAmerica’s oldest gas distribution com-panies, this process, which cores an 18-inch circular hole through all types ofpaved or hard surfaces and then rein-states the core for a permanent pave-ment repair, has been used byEnbridge for more than eight years,facilitating the cost-effective keyholemaintenance and repair program. Typicalkeyhole applications include: anaerobicjoint repair of cast iron pipe, low pres-sure service cut-offs, main separations,anode insertion for cathodic protection,service tee removal and replacement andgeneral daylighting or potholing for newpipe installations using horizontal direc-tional drilling.

Successfully employed without a sin-gle failure on more than 3,000 excava-tions in and around Toronto, Canada(population 2.5 million), under the mostsevere of climatic conditions, the processhas been formally accepted and certifiedby municipal authorities as a permanentreinstatement of composite pavement,saving the utility more than $5 million inpaving costs.

“It’s an undeniably better mousetrap,”said John Medeiros, Senior TechnicalAdvisor at ETI. “It was developed fromthe ground up by field-level personnellooking for a more effective and efficientway to access buried plant and equip-ment,” he said. “The fact that its cost canbe recovered in six to eight weeks fromsavings on paving costs and road cut feesis a bonus for utility companies lookingfor ways to reduce maintenance andrepair costs.”

At the same time, Enbridge alsoannounced a strategic alliance with UtilicorTechnologies Inc. of Toronto. Utilicor

becomes the exclusive manufacturer anddistributor of the rotary coring unit, respon-sible for both the distribution and sale ofthe unit and the proprietary bonding com-pound called “Utilibond”. Utilibond is anintegral part of the permanent pavementreinstatement process and has a proven

bond strength that is capable of supportingthe combined weight of six transit buses.

Gord Reynolds, who joins Utilicor asvice president of operations after fiveyears with Badger Daylighting, one ofNorth America’s largest vacuum excava-tion firms, says the rotary cutter and reha-bilitation process is the most cost-effectivebreakthrough in excavation since theintroduction of vacuum excavation in theearly 1990s.

“The unit can core through any hardsurface—including concrete reinforcedwith half-inch rebar—and allows us toopen up the hole in less than 15 minutes,retain the core or coupon, and then per-manently reinstate the road or sidewalkwithin 45 minutes,” Reynolds said.“Instead of an average of two keyholerepairs per day using the old methods, atypical two-man crew can do four or fiveand you don’t have to revisit the site lateron with paving crews. It’s all done in oneday. The savings in time and scheduling,as well as cost, are tremendous.”

The coring process, now called“Utilicoring,” is also used by MichiganConsolidated Gas (MichCon), America’sninth-largest gas distribution companywith more than 1.2 million customers,and by UGI, a medium-sized gas compa-ny serving the Lehigh Valley ofPennsylvania. Baltimore Gas & Electric,with almost 500,000 customers and NicorGas of Chicago, the third-largest local gas

distribution company in the U.S., withmore than 1.7 million customers, alsohave purchased Rotary Coring units.

The principal element of the Enbridgesolution is a truck-mounted, rotary cut-ting unit (patent pending) that cuts an18-inch circular hole in flexible, composite

and reinforced concrete pavement sys-tems or sidewalks. No jackhammers orbackhoes are required and no spoil ordebris that must be disposed of is creat-ed. The core of pavement is removed inone solid piece and set aside for reuse.The utility then vacuum excavates thehole down to the pipe and performs therepair from the surface using speciallong-handled tools in a manner that mir-rors laparoscopic or microsurgery in themedical field.

Once the repair has been completed, thehole is backfilled to the level of the base ofthe pavement and the core or “coupon” ofpavement is reinserted back into the roadsurface where it is permanently bonded tothat surface by a special proprietary bond-ing compound (“Utilibond”), which createsa bond stronger than the original pave-ment. No temporary patching or repavingof the site is required. Forty-five minutesafter the repair has been completed theroad can be opened for traffic.

Not only are the keyhole processesinherently safer, faster and less disruptiveof traffic, environmentally friendly, andeasier on the workers, but the increasedproductivity and the reduction in reinstate-ment and repaving costs and road cut feescan save the utility thousands of dollars perhole. It is a one-stop continuous repair andreinstatement process that leaves the road-way in as strong and stable a condition asthe day it was first constructed. P&GJ

Enbridge Introduces New Rotary Tool For Improved Pavement RepairsSpecial to Pipeline & Gas Journal

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The rotary cutter can cut an 18-inch circular hole in flexible, composite and reinforced concrete pavement systems.

Reprinted from Pipeline & Gas Journal/December 2002/pipelineandgasjournalonline.com