attock cement maintenance

8/17/2019 Attock Cement Maintenance

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PLANT MAINTENANCE ASSIGNMENT

PREVENTIVE MAINTENANCE

ATTOCK CEMENT PAKISTAN LIMITED

GROUP MEMBERS

ME-171

ME-173

ME-178

ME-188

ME-193

ME-206

ME-309

ME-310

ME-315

ME-324

ME-338


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Introduction

The journey of Attock Cement started from the year 1981 and the

company started its commercial production in 1988. In 25 years, companyhas shown steady growth. ACPL has attained new peaks every year

through strong team work, continuous modernization of plant to

improve efficiency and with utmost hard work. ACPL has cemented its

place not only in the local market but also in the regional markets through

selling quality products. ACPL’s current production capacity is 2,400MTPD. Due to an overall surge in cement demand in the country over the

last couple of years coupled by growth in regional market, ACPL has

decided to increase its production capacity to 5,400 MTPD by setting up a

new plant with a capacity of 3,000 MTPD. The new plant started operation

in June 2003.

Our Visit To Attock Cement Plant

We visited the cement plant of attock industries for the sole purpose ofunderstanding the working and maintenance strategies followed by the

engineers and maintenance staff with regard to the different machineries

operated in day to day production to meet the increasing demand of

cement in modern day.

To understand the working of maintenance schedules in a cement industry,

one must first be aware of the processes carried out in order to produce

different types of cements. Attock Cement produces three types of products under cement category namely

Ordinary Portland Cement

Sulphate Resistant Cement

Block Cement


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Cement: is a material with adhesive

and cohesive properties which make

it capable of bonding minerals

fragments into a compact whole. For

constructional purposes, the meaning

of the term "cement" is restricted to

the bonding materials used with

stones, sand, bricks, building stones,

etc. The cements of interest in the

making of concrete have the

property of setting and hardening

under water by virtue of a chemicalreaction with it and are, therefore,

called hydraulic cement. The name

"Portland cement" given originally

due to the resemblance of the color and quality of the hardened cement to

Portland stone – Portland island in England.

Manufacture of Portland cement

Raw materials

• Calcareous material – such aslimestone or chalk, as a source of

lime (CaO).

• Clayey material – such as clay orshale (soft clayey stones), as a source

of silica and alumina.

Wet process

When chalk is used, it is finely

broken up and dispersed in water in a

washmill. The clay is also broken up

and mixed with water, usually in a

similar washmill. The two mixturesare now pumped so as to mix in


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predetermined proportions and pass through a series of screens. The

resulting – cement slurry – flows into storage tanks.

When limestone is used, it has to be blasted, then crushed, usually in two

progressively smaller crushers (initial and secondary crushers), and thenfed into a ball mill with the clay dispersed in water. The resultant slurry is

pumped into storage tanks. From here onwards, the process is the same

regardless of the original nature of the raw materials.

The slurry is a liquid of creamy consistency, with water content of

between 35 and 50%, and only a small fraction of material – about 2% -larger than a 90 µm (sieve No. 170).

The slurry mix mechanically in the storage tanks, and the sedimentation of

the suspended solids being prevented by bubbling by compressed air

pumped from bottom of the tanks.

The slurry analyze chemically to check the achievement of the required

chemical composition, and if necessary changing the mix constituents to

attain the required chemical composition.

Finally, the slurry with the desiredlime content passes into the rotary

kiln. This is a large, refractory-

lined steel cylinder, up to 8 m in

diameter, sometimes as long as 230

m, which is slightly inclined to the

horizontal.

The slurry is fed in at the upper endwhile pulverized coal (oil or

natural gas also might be used as a

fuel) is blown in by an air blast at

the lower end of the kiln, where the

temperature reaches about 1450oC.

The slurry, in its movement down

the kiln, encounters a progressively


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higher temperature. At first, the water is driven off and COR 2R is

liberated; further on, the dry material undergoes a series of chemical

reactions until finally, in the hottest part of the kiln, some 20 to 30% of the

material becomes liquid, and lime, silica and alumina recombine. The

mass then fuses into balls, 3 to 25 mm in diameter, known as clinker. The

clinker drops into coolers.

Dry process

The raw materials are crushed and fed in the correct proportions into a

grinding mill, where they are dried and reduced in size to a fine powder.

The dry powder, called raw meal, is then pumped to a blending silo, and

final adjustment is now made in the proportions of the materials requiredfor the manufacture of cement. To obtain a uniform mixture, the raw meal

is blended in the silo, usually by means of compressed air.

The blended meal is sieved and fed into a rotating dish called a granulator,

water weighing about 12% of the meal being added at the same time. In

this manner, hard pellets about 15 mm in diameter are formed.

The pellets are baked hard in a pre-heating grate by means of hot gasesfrom the kiln. The pellets then enter the kiln, and subsequence operations

are the same as in the wet process of manufacture.


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Grinding of the clinker

The cool clinker (produced by wet or dry process), which is

characteristically black and hard, is underground with gypsum

CaSO4.2H2O in order to prevent flash setting of the cement, and tofacilitate the grinding process. The grinding is done in a ball mill. The

cement discharged by the mill is passed through a separator, fine particles

being removed to the storage silo by an air current, while the coarser

particles are passed through the mill once again.

Apron Conveyors:Apron conveyors consist of endless

chains with attached overlapping and

interlocking plates to provide a

continuous-carrying surface that

forms a leakproof bed suitable for

bulk materials without containers.

Move loose bulk materials like coal,lime, sand, stone, and sugar cane

along horizontal or inclined

conveyors. Apron Conveyors are

especially useful as feeders to

elevating systems, for picking tables

and loading booms, and for long

horizontal or inclined conveyors. In

cement industry, it is used to feed theraw material into the gypsum crusher.

There are three areas where the inspection is performed on yearly basis

which includes the drive, driven sprocket bearing and gear box bearing

and internals


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Problem Potential cause Solution

Chain rises off

sprocket

Excess chain slack.

Excess wear at the bases

of

sprocket teeth.

Excess chain extension.

Foreign material stuck to

the

bases of sprocket teeth.

Adjust the amount of

slack.

Replace the sprocket.

Replace the chain.

Remove the foreign

material

from the bases of the

teeth.

Chain separates

poorly from

the sprocket

Sprocket misalignment.

Excess chain slack.

Excess wear at the bases

of

sprocket teeth.

Adjust alignment.

Adjust the amount of

slack.

Replace the sprocket.

Wear to sides of link

plates

and sprockets

Sprocket misalignment. Adjust alignment.

Poor chain flexure Inadequate oiling.

Foreign materials

between pins

and bushes.

Corrosion between pins

and

bushes. Sprocket misalignment.

Lubricate properly.

Wash the chain to

remove

foreign materials, then

oil it.

Replace with an

environmentresistant chain series.

Adjust alignment.

Abnormal noise Chain is too tight or too

loose.

Inadequate oiling.

Excess wear of sprockets

and

chain.

Contact with the chaincase.

Damaged bearings.

Sprocket misalignment.

Adjust slack.

Lubricate properly.

Replace chain and

sprockets.

Eliminate contact with

the

case. Replace the bearings.

Adjust alignment.

Chain vibration Excess chain slack.

Excess load variation.

Excess chain speed leading

to

pulsation.

Chain flexes poorly atsome

Adjust slack.

Reduce load variation or

replace chain.

Use guide stoppers to

stop

chain swaying. Remove the affected


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points.

Sprocket wear.

points.

Replace the sprockets.

Damage to pins,

bushings,

rollers

Deformation of link

plate

Holes

Inadequate oiling.

Jammed foreign bodies.

Corroded components.

Use with greater than

allowable

load.

Abnormal load action.

Lubricate properly.

Remove foreign bodies.

Replace with an

environment

resistant chain series.

Review chain and

sprocket

selections.

Eliminate the abnormal

load,

and review chain and

sprocket

selections.

Overall corrosion

Corrosive wear

Corrosion due to

moisture,

acid or alkali.

Replace with an

environment

resistant chain series.

Precautions for Maintenance Personnel:

The following precautions must be observed:

1.

Do not perform maintenance while the conveyor is operating. Lockout the circuit breaker disconnect switch with personal padlocks on

the conveyor before performing maintenance. For belt tracking or

listening for bearing noise, never touch a moving belt, roller, pulley,

or bearing. All inspections and adjustments can be made from

outside the conveyor. Never reach under or into the conveyor when

the belt is running.

2. Before restarting the conveyor, make sure all personnel are clear of

moving parts.3. Maintain good housekeeping in the vicinity of the conveyor at all

times. Clean up spilled materials or lubricants promptly.

4. Always replace the safety guards and protective devices before

putting the conveyor back in service. Do not run the conveyor with

the chain drive guards open or missing.

5. Maintenance personnel should be alert for hazardous conditions at

all times. Remove sharp edges and protruding objects and replace

broken or worn parts promptly.


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6. When using air hoses and drop cords, string them to avoid creating a

tripping hazard.

7. Always stop the conveyor to clear jams or to remove foreign objects.

8. Use the proper tool for each job. Carry tools in a pouch or a tool box.

Never carry tools in pockets.

9.

Wear goggles while using compressed air.

10. Do not direct the stream of air toward yourself or other

workers.

11. Do not use compressed air to clean yourself or your clothing.

12. Horseplay with compressed air is extremely dangerous.

13. Do not smoke while using solvents or cleaning fluids.

14. Report all accidents resulting in personal injury or damage to

equipment or material, and all irregularities in equipment operation,

promptly to the proper authority.

Gypsum Crusher:

After the raw materials have been transported to the plant, the limestone

and shale which have been blasted out of the quarry must be crushed into

smaller pieces. Some of the pieces, when blasted out, are quite large. The

pieces are then dumped into primary crushers which reduce them to thesize of a softball. The pieces are carried by conveyors to secondary

crushers which crush the rocks into fragments usually no larger than 3/4

inch across.

In crushers, the shaft bearing are inspected on the yearly basis while the

beaten, grizzly bar and liners on the semi yearly basis through different

NDT techiniques and vibration analysis

Gypsum Crusher Deduster:

It is intermediate step towards the preparation of raw material in which

Before blending, dust is removed by deduster after coming out of crusher.

Inspection of deduster includes the checking of fan shaft bearings, impeller

and rotary valve gear box.


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Bearing troubles symptoms and sources:

Symptoms Sources of trouble Examples

Uneven running Damaged rings or

rolling elements

Motor vehicles:

more and more wheelwobbling

increased tilting

clearance

vibration of steering

system

Contamination Fans:

growing

vibration

Excessive bearing

clearance

Saw mills:

more knocks and blows

in connecting rods

Reduced

working accuracy

Wear due

to contaminants

or insufficient

lubrication

Lathe:

gradual development

of chatter marks on

workpiece

Damaged ringsor rolling elements

Grinders:wavy ground surface

Change in adjustment

(clearance or preload)

Cold rolling mill:

Periodic surface defects

on rolled material

such as stretcher

strains,

ghost lines etc.

Unusual

running noise:

whining or squealing

noise

Insufficient operating

clearance

rumbling

or irregular

noise

Excessive clearance

Damaged contact areas

Contamination

Unsuitable lubricant

Electric motors

Gears

(the bearing noise

is hard to identify

since it is generally

drowned by the noiseof the gears)


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gradual change

in running

Change in operating

clearance

noise due to

temperature

Damaged running track(e.g. due to

contamination

or fatigue)

CEMENT MILL

CEMENT MILL PROCESS

The clinker is stored in two silos of clinker and storage.

Each Silo has six extraction holes. 4 belt conveyers overtake the extraction

clinker, 3 extractions for in belt conveyer. The 4-belt conveyers discharge

the clinker onto the long belt conveyer, which leads it to the clinker

hopper.

Clinker extraction de-dusted by the two-bag filter installation and fans.The extraction clinker and gypsum are stored into corresponding hopper.

These are metal hopper mounted on load cells (one load cell and 2 fix

propying for each hopper).

The clinker hopper has the capacity of 180 tons and while the gypsum has

110 tons capacity hopper. The hoppers are connected to a de-dusting and

fans.

The material is extracted from each hopper by means of weigh feeder and

introduced into the mill-feeding funnel.

The clinker and gypsum are ground in a closed circuit mill system,

composed of;

Ball mill dia 4.2 x 13.0m length

Bucket elevator of 450t/h


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Separator diameter 5m with satellite cyclones and a separator fan. Air slide

for feeding the elevator and separator and for conveying coarse and fine

material.

PROCESS FLOW OF CEMENT MILL

By grinding the material, cement and cement coarse is obtained. The

ground material is discharge through on air slide into the bucket elevator.

Bucket elevator lifts the material up to height wherefrom an air slide feed

it into the separator. The separator has 8 cyclones and separator fan for the

recycled air and a D.C. drive mounted on separator. Speed is adjustedaccording to the established grinding fines and laboratory analysis.

The coarse separated through the central separator body is discharged

through a swiveling flap into an air slide. It is discharged by mean of flow

meter into a feeding funnel of the mill.

The fine fraction material lifts up by the drag force apply by separator fan

and fine fraction transfer into cyclones and the material dropped through

(gravitational force). Rotary valve to air slide from where material goesinto airlift and from air lift the material through air slide on silo top

dropped in the silo.

From the mill discharge E.P. fan lifts the light particles through the air and

produced induced draft. From where material lift up and goes into E.P.,

these particles are electromagnetic and in the E.P. produce high voltage

current through H.T. motor about 60.000 volt and produce electromagnetic

field. In the E.P the plates and wire are place when the current passedthrough the plates and wires it becomes magnet and produces

electromagnetic field when the particles which carry through air passed

from this magnetic field these plates and wires collects these negative and

positive electromagnetic particles and after sometime on E.P placed

rapping motor for plates and wires which rapping on it, the collected

particles dropped through the plates and wires and dropped into screw

conveyer. From where this material convey into fine air slide becausethese material are fine.


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GRINDING:

The final step in Portland cement manufacturing involves a sequence of

blending and grinding operations that transforms clinker to finished

Portland cement. Up to 5 percent gypsum or natural anhydrite is added tothe clinker during grinding to control the cement setting time, and other

specialty chemicals are added as needed to impart specific product

properties. This finish milling is accomplished almost exclusively in ball

or tube mills. Typically, finishing is conducted in a closed-circuit system,

with product sizing by air separation.

CONVEYORS:

Clinker extraction belt conveyor take the clinker out of Air quenched

clinker cooler and feed it into the main belt which led to weigh feeder.

Inspection the these conveyors include the yearly checking of drive drum

bearing, tensioning drum bearing and gear box internals and bearing in theclinker extraction bearing. Snub pulley bearing is also checked in the

inspection of main clinker long belt conveyor along with other bearings. In

weigh feeder, same components as the first bearing is inspected. All the

inspection is done visually or through the concern problem detection

technique which may include vibration analysis, or NDT- techniques.

GRINDING MILL:

A Ball mill is a horizontal cylinder partly filled with steel balls (oroccasionally other shapes) that rotates on its axis, imparting a tumbling

and cascading action to the balls. Material fed through the mill is crushed

by impact and ground by attrition between the balls. The grinding media

are usually made of high-chromium steel. The smaller grades are

occasionally cylindrical ("pebs") rather than spherical. There exists a speed

of rotation (the "critical speed") at which the contents of the mill would

simply ride over the roof of the mill due to centrifugal action. The criticalspeed (rpm) is given by: nC = 42.29/√d, where d is the internal diameter in


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metres. Ball mills are normally operated at around 75% of critical speed,

so a mill with diameter 5 metres will turn at around 14 rpm.

Inspection of Grinding mills include the various components of the

grinding mill, air slide blower and bucket elevator such as Ultra sonicinspection inlet/outlet trunnion, Dye Penetrant (DP Test) inlet/outlet

trunnion, Mill Trunnion White Metal Bearings, Pinion Shaft Bearings (04

Nos), Transmission Shaft Bearings (04 Nos), Drive 1 Gear Box Internals

& Bearings, Drive 2 Gear Box Internals & Bearings etc. these inspection is

yearly, semiannually, monthly or semimonthly depend upon the severity of

the equipment.

DYNAMIC SEPARATOR:

It works by injecting the material stream to be sorted into a chamber which

contains a column of rising air. Inside the separation chamber, air drag on

the objects supplies an upward force which counteracts the force of gravity

and lifts the material to be sorted up into the air. Due to the dependence of

air drag on object size and shape, the objects in the moving air column are

sorted vertically and can be separated in this manner.

Air classifiers are commonly employed in industrial processes where a

large volume of mixed materials with differing physical characteristics

need to be separated quickly and efficiently. One such example is in

recycling centers, where various types of metal, paper, and plastics arrive

mixed together and need to be sorted before further processing can take

place.

In inspection of dynamic separator or separator fan includes yearlyinspection and rectification of the following components:

1. Vertical Shaft Bearings

2. Gear Box Internals & Bearings

3. Vane & Casing

4. Rotary Locks Internals & Brgs (08 Nos)

5. Shaft Bearings


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6. Damper Inspection

7.

Impeller Inspection

8. Inspection of Casing & Foundation Pads

Iron remover:

The purpose of iron remover is to remove any metallic part from the

cement and it is done by using magnetic techniques.

Inspection and rectification of the iron remover includes visual inspection

and vibration analysis of:

1.

Drive Drum Bearings

2. Driven Drum Bearings

3.

Gear Box Internals & bearings

4. Drive Pulley and V-Belt

Roller Press:

These consist of a pair of rollers set 8 – 30 mm apart and counter-rotatingwith surface speed around 0.9 - 1.8 m.s−1. The bearings of the rollers aredesigned to deliver a pressure of 50 MPa or more. The bed of material

drawn between the rollers emerges as a slab-like agglomeration of highly

fractured particles. The energy efficiency of this process is comparatively

high. Systems have been designed, including a de-agglomerator and

separator, that will deliver material of cement fineness. However, particle

size distribution is again a problem, and roll presses are now increasingly popular as a "pre-grind" process, with the cement finished in a single

chamber ball mill. This gives good cement performance, and reduces

energy consumption by 20-40% compared with a standard ball mill

system.

Inspection of Roller Press Includes the visual and visual aid inspection of

the following components:

1.

Universal Couplings


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2. Planetry Gear # 01 Internal/bearings

3.

Planetry Gear # 02 Internal/bearings

4. Fix Roller bearings

5. Moveable Roller bearings

6.

Torque Supports arrangement

7. Rollers Hard facing condition

8.

Hydraulic System

9.

Lubrication system (Gear)FGM Bag Filter (Inlet side):

It is the last part of this step in which the sand is pass through a set screens

to separate the coarse particles from the fine and desire one.

Yearly and 2 yearly inspection is performed on the equipment:

1.

Fan Impeller/Casing

2. Fan bearings/Housing Inspection

3.

Drag Chain & drive /driven sprockets

4. Drag Chain drive /driven Bearings

5. Rotary valve gear box inspection


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PREVENTIVE MAINTENANCE SCHEDULE OF CEMENT MILL

Jul Aug Sep Oct Nov Dec Jan Fe b Mar Apr May Jun

15 15 15 15 15 15 16 16 16 16 16 16

Drive Drum Bearings Mar-15 Y

Tensioning drum Bearings Mar-15 Y

Gear Box Internals & Bearings Mar-15 Y

Clinker Long Belt Drive Drum Bearings Mar-15 Y

Conveyor Tensioning drum Bearings Mar-15 Y

Snub Pulley Bearings Mar-15 Y

Gear Box Internals & Bearings Mar-15 2Y

Drive Drum Bearings Mar-15 Y

Tensioning drum Bearings Mar-15 Y

Gear Box Internals & Bearings Mar-15 2Y

Inspection not carried out, give

reasons

1

S.

#Eqpt Name / #

Clinker Extraction

Belt Conveyor

Weigh Feeder

Inspection carried out, found O.K.

Replac.

Freq.

Last

Replac.

Date

Next

Replac.

Date

Inspection Details

emar s easons or

Inspection carried out

before/after the schedule dates or

not carried out

Inspection ScheduleLast

Insp.

Date

s o

ry

File

#

Insp

Freq

Colour Codes

3

2

Inspection carried out, under

observation

Inspection carried out,

rectification required

Ultra sonic inspection inlet/outlet trunnion Mar-15 3 M

Dye Penetrant (DP Test) inlet/outlet trunnion Jun-15 15 D

Mill Trunnion White Metal Bearings Oct-15 Y

Pinion Shaft Bearings (04 Nos) Jun-15 Y

Transmission Shaft Bearings (04 Nos) Apr-15 Y

Drive 1 Gear Box Internals & Bearings Apr-15 6M

Drive 2 Gear Box Internals & Bearings Apr-15 6M

Auxiliary Gear Box 1 Internals & Brgs Apr-15 2Y

Auxiliary Gear Box 2 Internals & Brgs Apr-15 2Y

Heat Exchangers Inspection & cleaning Jun-15 Y

Girth Gear fastening & Joining Bolts Inspection Jun-15 Y

Blower Bearings Aug-14 Y

Blower Impeller Inspection Aug-14 Y

Airslide Canvas Aug-14 Y

Drive Drum Bearings Apr-15 Y

Tensioning Drum Bearings Apr-15 Y

Drive/Tensioning Drum Inspection Apr-15 6M

Gear Box Intenals & Bearings Jun-15 2Y

Geared Coupling Inspection Jun-15 Y

Inspection not carried out, give

reasonsColour Codes

4

5

6




observation

Cement Grinding Mill

Air Slide Blowers

Inspection carried out, found O.K.

Bucket Elevator


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PREVENTIVE MAINTENANCE SCHEDULE OF GYPUM CRUSHING AREA

Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

15 15 15 15 15 15 16 16 16 16 16 16

Gypsum Apron Drive Sprocket Bearings Mar-15 Y

Conveyor 1 Driven Sprocket Bearings Mar-15 Y

Gear Box Bearings & Internals Mar-15 Y

Gypsum Crusher Shaft Bearings Inspection Apr-15 Y

Inspection of Beaters Jan-15 6 M

Inspection of Grizzly Bar Apr-15 6 M

Inspection of Liners Apr-15 6 M

Gypsum Crusher Fan Shaft Bearings Feb-15 Y

Deduster Impellor Inspection Feb-15 Y

Rotary Valve Gear Box Feb-15 2 Y

Replac.

Freq.

Colour Codes

GYPSUM CRUSHING AREA

Inspection not carried

out, give reasonsInspection carried out, found O.K.

Inspection Details

Next

Replac.

Date

Last

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Date

1

1




observation

1

2

3

S.

#Eqpt Name / #

for Inspection carried

out before/after the

Inspection ScheduleLast

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Date

ory

File

Insp

Freq


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PREVENTIVE MAINTENANCE SCHEDULE OF PACKING AREA

Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

15 15 15 15 15 15 16 16 16 16 16 16

Fan Shaft Bearings Mar-04 Y

Deduster bags Y

Rotary Valve Gear Box 2 Y

Rotary Valve Bearings 2 Y

Si lo Discharge De vi ce A ir Sli de Canvas Insp ecti on Jan-15 Y

Pneumatic jack inspection Jan-15 Y

Actuator inspection Jan-15 Y

Rotary Valve Rotor Oct-14 Y

Gear box Internal and bearings Oct-14 Y

Air bed belt conveyor Motorize drum internal Feb-15 Y

Tail drum bearings Feb-15 Y

Snub drum bearings Feb-15 Y

Blower impellor inspection Feb-15 Y

Vibrating Screen Mesh Inspection Apr-15 6 M

Roto Packer Packer drive gearmotor internals bearing Dec-15 Y

Vertical shaft bearing Inspection Dec-15 Y

Nozzle Pulley bearings Inspecion Dec-15 Y

Inspection not carried out, give reasonsInspection carried out, under observationInspection carried out, rectification

required

Eqpt Name / #

PACKING AREA

Remarks / Reasons for Inspection carried out before/after

the schedule dates or not carried out

Inspection Schedule

Colour Codes Inspection carried out, found O.K.

Last

Insp.

Date

History

File #

Insp

FreqInspection Details

Cement Mill Deduster


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PROCESS FLOW OF PACKING PLANT:

In packing plant the cement material is taken through silo bottom, (central

discharge). In each silo’s two extraction are place, one is in operation and other

one is on standby. Each extraction has one manual gate valve, one pneumaticvalve, and one motorize valve. Manual and pneumatic valve 100% open and we

control the feed flow with respect to motorize opening. From the extraction

material goes into air slide, from the air slide to bucket elevator. Bucket elevator

lift up the material and put into vibrating screen. In vibrating screen mesh are

placed and in vibrating screen material flow through its inclination and vibration.

Fine material pass through the mesh and residue are on the screen. That material

are rejected and out from our system by duct pipe.

The fine material through screen goes down into hopper; from the hopper through

rotary valve material goes into ROTO PACKER tank. In the tank material

maintain through level prop, if the material level down the pneumatic jack is

operate and with respect to pneumatic jack rotary valve is operate and the material

flow into tank from hopper, if the level of rotor packer tank is maintain then

pneumatic jack is off as well as rotary valve also.

ROTO PACKER OPERATION:

Rotor packer work is in this manner, if a person place the bag on nozzles and the

bag touch the strips which are place along the nozzles then that strip operate and a

hanger are place which hangs or hold the bag and with respect to that a pneumatic

jack is operate and the rotor packer material discharge motor as well as operate and

the material comes into nozzles and bag filling start.If the bags weight is complete (50kg) the bag filling off and pneumatic jack close

and rotor packer motor for bag filling is also off and bag dropped onto belt

conveyer and loading onto the trucks.

attock cement maintenance

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