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SAND, GRAVEL, AND CRUSHED STONE

ON-THE-JOB TRAINING MODULES

UNITED STATES DEPARTMENT OF LABORELAINE L. CHAO

SECRETARYMINE SAFETY AND HEALTH ADMINISTRATIONDAVE D. LAURISKI

ASSISTANT SECRETARYOriginally Published AUGUST 2000

INSTRUCTION GUIDE SERIESMSHA IG 40

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These training modules were developed cooperatively by MSHA and members of the sand,gravel, and crushed stone industry. We gratefully acknowledge the valuable contributionsof Gifford-Hill and Company, Inc., National Gypsum Company, National Stone Association,The Spline Education Center, Martin-Marrietta Corp., W. W. Boxley Co.,and others, to thisInstruction Guide.

Copies of this Instruction Guide, and others in this series, may be ordered by calling, orwriting:

National Mine Health and Safety AcademyOffice of the Business Manager1301 Airport RoadBeaver, WV 25813

Phone: (304) 256-3257

or by contacting your local MSHA office.

This Instruction Guide is designed to supplement existing health and safety trainingprograms. The material is not intended to cover all specific jobs at any given operation.Other modules may be added, and existing modules revised, in future printings of thisInstruction Guide.

Individual modules in this Instruction Guide are designed to be used separately. Themodules can be kept together in a three ring binder when not in use. General informationand training recommendations are included at the end of each module.

DISCLAIMER

The information and recommendations contained in this publication have been compiledfrom sources believed to be reliable, and to represent the best current opinion on thesubject matter. No warranty, guarantee, or representation is made by MSHA as to theabsolute correctness or sufficiency of any representation contained in this publication, andMSHA assumes no responsibility in connection therewith. Nor can it be assumed that allacceptable safety measures are contained in this publication, or that other, or additional,measures may not be required under particular, or exceptional circumstances.

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TABLE OF CONTENTSMODULE STARTING THE PLANTMODULE PLANT CLEAN-UPMODULE PLANT SHUTDOWNMODULE PLANT OPERATIONMODULE MAINTAINING CONVEYOR SYSTEMSMODULE PLANT REPAIRMODULE WELDING AND CUTTINGMODULE EQUIPMENT LOCK-OUT PROCEDURESMODULE ELECTRICAL PROCEDURES FOR NON-ELECTRICIANSMODULE 10 TRUCK HAULAGEMODULE 11 GROUND CONTROLMODULE 12 INSPECTING AND REPLACING CABLES (WIRE ROPES)MODULE 13 REPLACING THE DRIVE CHAIN OR BELT ON A SCREW CONVEYORMODULE 14 MANUAL HANDLING OF MATERIALSMODULE 15 USING AN OVERHEAD HOIST TO LIFT OR HANDLE PARTS OR MATERIALSMODULE 16 HANDLING MATERIAL WITH A SHOP OVERHEAD TRAVELING CRANEMODULE 17 PRIMARY CRUSHING OPERATIONMODULE 18 OPERATING DRILLING EQUIPMENTMODULE 19 TRANSPORTATION, USE, AND STORAGE OF EXPLOSIVES

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MODULE NUMBER 1OFINSTRUCTION GUIDE NUMBER 40

ON-THE-JOB TRAINING MODULESFOR THESAND, GRAVEL, AND CRUSHED STONE

STARTING THE PLANT

This module describes basic job steps, potential hazards and accidents, and recommendedsafe job procedures for plant start-up.

This job is usually done by the plant operator, but may be done by other occupations, suchas utility worker, laborer, etc. The plant operator/utility worker must make sure thatemployees, and others, are protected from accidents and injuries resulting from plant start-up.

While both sand and gravel plants, and crushed stone plants, are built by many differentmanufacturers, the processes and equipment involved in the production effort are similar.

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SAND AND GRAVEL PLANTS

At a typical sand and gravel plant, raw material from a hopper at a dumping station is carriedby a conveyor belt to a screening deck. The screening deck removes oversized material(large clay balls, roots, very large rocks, etc.), separates sand from gravel, and then separates

the gravel into different sizes. Spray bars wash the gravel as it passes through the screeningdeck.

Large stones then go to log washers, while medium size material (chat and/or pea gravel) iscarried to a screw. The large stone, after emerging from the log washer, and the finermaterial, after emerging from the screw, pass through separate final rinse stations on the wayto storage areas. Transportation to a storage area may be by a fixed conveyor system, aradial stacker system, or an extendable belt conveyor system. A radial stacker is a conveyorsystem that rotates from a fixed pivot point, and stores the conveyed material in an arc-shaped stockpile. The extendable belt conveyor system has the capability of lengthening orshortening itself by moving the head section. The head section is mounted on wheels, and

moves on rails, which allows the conveyor to supply several stockpiles, hoppers, or silos.

Sand, after being separated on a screening deck, flows to a classifier, where it is washed andsized. The sand is then carried by a screw, which separates the sand from the water, to aconveyor belt, which carries it to a storage area.

Water that is used in the plant is pumped from a freshwater pond. The discharged water isthen pumped into a settling pond.

A crushed stone plant differs somewhat from a sand and gravel plant. Raw material isbrought from a quarry to a primary crusher by rear dump haul trucks. Some primary crushers

are fed by wobblers, which are chain driven conveying systems with eccentric rollers.

After primary crushing, material is conveyed by belt to a scrubber for washing. The scrubberis a cylindrical, rotary device with internal screens and auger type vanes that carry thematerial through the scrubber. Fine material is separated from the coarse material in thescrubber. The fine material is sent to a settling pond. The coarse material is sent to a surgepile, and then to a primary screening deck. Oversized material is carried from the primaryscreening deck to secondary crushers, and is then returned to the primary screening deck tobe separated into desired products. A crushed stone plant contains a series of screeningdecks, crushers, and final rinse screening stations. Finished product travels through a finalrinse stage, and is then stored in silos, bins, or stockpiles.

A sand and gravel, or crushed stone, plant consists of a number of interdependent productionprocesses. Therefore, it is important to know how the plant operates in order to prevent amassive pile-up of material at a transfer point during plant start-up.

An improper start-up sequence can damage plant equipment, and also increase the risk ofinjury. Fresh-water, sand, and other pumps are started first. Other plant equipment must be

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started in reverse order of material flow, beginning with the finished product conveyor, andworking back through the primary hopper feeder belt.

In addition to following the proper start-up sequence, the person starting the plant must takeevery precaution to ensure that other people are clear of equipment before the equipment isstarted.

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The following safe job procedures will help to minimize incidents that may cause injuries, andadversely affect production.

REQUIRED, OR RECOMMENDED, PERSONAL PROTECTIVE EQUIPMENT:HARD HAT, STEEL-TOED SHOES, LIFE JACKET, GOGGLES

SEQUENCE OF POTENTIAL ACCIDENTS

BASIC JOB STEPS OR HAZARDS

1. Start primary 1. A) Falling into water.pump.

B) Slipping/falling onplatform.

C) Electrocutionhazards.

D) Mechanicalhazards.

2. Start all 2. A) Personnel caught inconveyors, conveyors andshakers, and other equipment.associatedequipment instart-upsequence.

B) Spillage at transferpoints.

C) Short circuit inswitch box.

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RECOMMENDED SAFE JOB

PROCEDURES

1. A) Wear life jacket.

B) Use designated walkways,and examine forslipping/tripping hazards.

C) Examine work area forexposed wires, frayedinsulation, etc.

D) Examine work area formissing guards, exposedmoving machine parts,etc. Sound warning horn,if applicable.

2.A) Check that all movingparts have guards inplace. Make sure allpersonnel are clear ofequipment. Sound alarm.

B) Proper start-up sequencebegins with finished

product belts, andcontinues to primaryfeeder.

C) Stand to the side of switchbox, in case door blowsopen when activated.

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SEQUENCE OF

BASIC JOB STEPS

3. Inspect theoperating plant forproblems andhazards.

POTENTIAL ACCIDENTS

OR HAZARDS

D) Problems withequipment at start-up, such as electric

motor fires, beltslippage, etc.

3.A) Getting caught inmoving parts.

B) Tripping hazards.

C) Burns.

D) Electrical hazards.


PROCEDURES

D) Check piece of equipmentafter starting, beforestarting something else.

3.A) Check that all guards arein place. Cross belts onlyat designated crossovers.Do not extend any part ofbody beyond edge of belt.

B) Walkways should be keptclear of trash, tools, etc.Check for loose or missinghandrails, walkwaygrating, or toeboards.

C) Check for overheatedgearboxes (listen forgrinding sound). Check ifgearbox is loose on mainshaft. Visually checkbearings through guard

while running. Look fororange color on shaft, orshaft wobbling.

D) Check for obviouselectrical hazards, such asexposed wires, missing

junction box covers,frayed insulation, missinglight bulb guards, etc.

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GENERAL INFORMATION

This module is part of an Instruction Guide that was developed to assist the sand, gravel, andcrushed stone industry in conducting effective on-the-job training (OJT) of new employees,or employees reassigned to different jobs. The use of training materials, such as this module,is an important part of an effective, systematic, OJT program.

This Instruction Guide uses a generic Job Safety Analysis (JSA) of jobs common to theindustry. The JSA format facilitates uniform basic training in safe job procedures, whilerequiring only a minimum of time and effort on the part of the trainer. This material is genericto the industry; therefore, each company using this guide will need to tailor the materialsomewhat to fit their particular requirements. In some cases, the material must be generalin nature, and will not include specific details of procedures or equipment that must be taughtby the trainer.

Recommendations for an overall OJT program are contained in the Mine Safety and HealthAdministration (MSHA) guide: Structuring Effective On-The-Job Training Programs, June,1983.

TRAINING RECOMMENDATIONS

On-the-job training is usually best done by the employees immediate supervisor. If thesupervisor relies on another employee to do certain parts of the training, the supervisorshould be present to monitor the training. OJT is conducted at the actual job site where thework will be done.

The supervisor/trainer should use the training materials (this module, or other materials) whilethe training is being done, to help ensure that all job steps are covered, and that no importantsafety precautions are omitted. Effective OJT should begin with an explanation (lecture

and/or discussion) of the safe job procedure. The explanation should be followed by a hands-on demonstration of the proper job procedure. A good demonstration is, perhaps, the mostimportant part of OJT. The demonstration is followed by supervised practice, during whichthe supervisor/trainer coaches (corrects and encourages) the employee, and evaluates whenthe employee is ready to do the job without direct supervision.

The first step - explaining the job to the employee - can be done in different ways. Thesupervisor/trainer and the employee can sit down and go through the training materialstogether. It may be advantageous to provide the employee with a copy of the trainingmodules that are applicable to his/her job. The fact that most of the training is conducted atthe job site does not preclude the use of a classroom, or a quiet office, for the first part of the

training. Any general theory, or knowledge training, as well as the initial explanation of thejob procedure, may be best done in an office/classroom setting, especially when noise levels,or other conditions at the job site, make communication difficult. A complete series of jobsteps could be presented through the use of slides developed at the mining operation.

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ON-THE-JOB TRAININGFOR THESAND, GRAVEL, AND CRUSHED STONE INDUSTRY

PLANT CLEAN-UP

For the job of plant clean-up, this module describes the basic job steps, potential accidentsand hazards, and recommended safe job procedures.

A tremendous quantity of material passes through a typical plant every day. Obviously, anobjective is to deliver all the material to its final destination. However, because of the

characteristics of the material - variable nature, extremely abrasive, often coated withcohesive material - some spillage will occur, which may necessitate frequent clean-upactivities.

Belt conveyors are a major source of spillage. Spillage usually can be found at return idlers,tail pulleys, take-up pulleys, and transfer points. Chutes and skirt boards, that are used attransfer points, are subject to corrosion and wear from wet and abrasive materials. Holes willeventually form in chutes and skirt boards, resulting in spillage at transfer points.

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A considerable amount of fine material is present in unwashed material coming from thefeeder hopper to the main feeder belt. This unwashed material is usually coated with clay,and tends to stick to the belt. Return idlers, tail pulleys, and take-up pulleys pick up this claycovered material, and sling it onto surrounding surfaces. Chute boxes (skirt boards) may notcatch all of the material, thereby allowing it to accumulate at the tail pulley. Belts, other thanthe main feeder belt, are subject to smaller amounts of spillage and accumulated finematerial.

Spillage can also occur around scrubbers, crushers, shaker decks, classifier stations, andfinal rinse screening stations. Spillage in these areas can be caused by worn chutes,excessively wet material, or excessively high material feed rate. Material can bounce or rolloff shaker screens, especially when the screens become clogged with flat rocks or clay.Loose or broken connections at classifier dumping stations, just above splitting troughs, cancause considerable amounts of spillage.

Spillage around the plant area must be cleaned up, because it may create hazardoussituations, as well as economic loss. Accumulated material on walkways can be a trippinghazard, and, if permitted to build up to the top of toeboards, could even allow a person to slide

under the intermediate rail, and fall to the ground. Loose materials may also fall over thetoeboards and strike persons passing underneath. Wet spillage, which cakes on walkways,accelerates the corrosion process, which can eventually weaken the structure to the point thatit could fall under a persons weight. Economic advantages of clean-up include reduction inrust, better operation of the plant, more efficient work by employees, and fewer accidentsfrom spillage problems.

Spillage can be minimized if worn chutes, skirt boards, and other causes of spillage arereported and corrected. Mechanical belt cleaners reduce the clean-up job around conveyorsystems. In general, hazards will be reduced, and money can be saved, if spillage can be

minimized.

Typically, plant clean-up is done by utility workers, laborers, or conveyor belt crews. Wherepossible, clean-up activities should be scheduled to take place when the plant is shut down,in order to minimize hazards to employees working near moving equipment.

Clean-up workers use high pressure water hoses, shovels, and small front-end loaders.Injuries to clean-up workers include muscle strains (the most common), back injuries, and eyeinjuries (from water hoses).

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The following safe job procedures will help to minimize incidents that may cause injuries, andthat may adversely affect production.

REQUIRED OR RECOMMENDED PERSONAL PROTECTIVE EQUIPMENT:HARD HAT, STEEL-TOED BOOTS (RUBBER BOOTS RECOMMENDED), SAFETYGLASSES OR GOGGLES, RUBBER GLOVES RECOMMENDED, SLICKER SUIT

SEQUENCE OF

BASIC JOB

STEPS

1. Clean plantwalkways withhigh pressurehose.

POTENTIAL ACCIDENTS

OR HAZARDS

1. A) Eye injuries.

B) Struck by whippingwater hose.

C) Electrocution.

D) Bruises (struck bywater) from waternozzle.

E) Knocked intosomething.

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PROCEDURES

1. A) Wear safety glasses orgoggles.

B) Prevent hose from whippingby:1. Securing your grip.2. Using a helper.3. Standing on hose near

nozzle.4. Turning water on slowly to

a pressure with which youare able to walk.

C) Dont aim water hose directly

at electrical or junctionboxes.

D) Dont aim water hose atothers. Watch for people atother levels of the plant.

E) Dont stand with your backtoward open walkways,stairways, etc.

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SEQUENCE OF

BASIC JOB

STEPS

2. Clean-up aroundtail pulleys andtransfer points,tunnels, andother areas, asrequired, with ashovel.

POTENTIAL ACCIDENTS

OR HAZARDS

F) Slips and falls.

2. A) Getting caught inhead or tail pulley.

B) Getting shovelcaught in idlers.

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PROCEDURES

F) Dont climb or descendstairs while handling waterhose under pressure. Stand

with feet apart, one footbehind the other, and leanforward to brace yourselfagainst pressure of hose.Where possible, braceyourself securely against astationary object. Start fromhighest work area and workdown, washing platforms,walkways, and other placeswhere there is an

accumulation of material.Remove water hose fromthe walkway after you finish,to eliminate a trippinghazard.

2. A) Use long-handled shovel inall areas, except whererestricted clearance is aproblem. This reduces thepossibility of coming incontact with moving parts.Do not clean in guardedareas with the belt running.If you must clean-up inguarded areas, use properlockout/tagout procedures.

B) When shoveling onto amoving conveyor, alwaysshovel in the direction thebelt is traveling. The shovelwill be carried away fromyou, if it becomes hung inthe belt.

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SEQUENCE OF

BASIC JOB

STEPS

3. Cleaning upground area andplant with asmall loader(bobcat, etc.)

POTENTIAL ACCIDENTS

OR HAZARDS

C) Striking coworkers.

D) Back injuries.

E) Caught betweenmoving radialstacker andstationary object.

3. A) Overturning loader.

B) Damagingequipment, or plantstructure.

C) Striking otherpeople.


PROCEDURES

C) Watch out for others workingin the area.

D) Load the shovel moderately.Move your feet whenturning, rather than twistingyour body. Lift with yourlegs, not your back.

E) When working near the tailpulley of a radial stacker, donot get between the tailpulley and a stationaryobject.

A) During clean-up, operate theloader at less than halfthrottle, with the clutch in lowspeed. Do not operate theloader in a manner thatcauses any of the wheels toleave the ground. Do notoverload the bucket. Carrythe bucket in a low position

when transporting materials.Always fasten the seat belt.

B)Avoid bumping anyequipment, or plantstructures. Always checkbefore changing direction.Look in the direction oftravel. When parked, lowerbucket, set parking brake,and chock wheels.

C) Always check beforechanging direction. Look inthe direction of travel.

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GENERAL INFORMATION


This Instruction Guide uses a generic Job Safety Analysis (JSA) of jobs common to theindustry. The JSA format facilitates uniform, basic training in safe job procedures, whilerequiring only a minimum of time and effort on the part of the trainer. This material is genericto the industry; therefore, each company using this guide will need to tailor the materialsomewhat to fit their particular requirements. In some cases, the material must be generalin nature, and will not include specific details of procedures or equipment that must be taughtby the trainer.

Recommendations for an overall OJT program are contained in the Mine Safety and HealthAdministration (MSHA) guide: Structuring Effective On-The-Job Training Programs


On-the-job training is usually best done by the employees immediate supervisor. If thesupervisor relies on another employee to do certain parts of the training, the supervisorshould be present to monitor the training. OJT is conducted at the actual job site, where thework will be done.

The supervisor/trainer should use the training materials (this module, or other materials) whilethe training is being done, to help ensure that all job steps are covered, and that no importantsafety precautions are omitted. Effective OJT should begin with an explanation (lectureand/or discussion) of the safe job procedure. The explanation should be followed by a hands-on demonstration of the proper job procedure. A good demonstration is, perhaps, the mostimportant part of OJT. The demonstration is followed by supervised practice, during whichthe supervisor/trainer coaches (corrects and encourages) the employee, and evaluates whenthe employee is ready to do the job without direct supervision.

The first step - explaining the job to the employee - can be done in different ways. Thesupervisor/trainer and the employee can sit down and go through the training materialstogether. It may be advantageous to provide the employee with a copy of the trainingmodules that are applicable to his/her job. The fact that most of the training is conducted atthe job site does not preclude the use of a classroom, or a quiet office, for the first part of thetraining. Any general theory, or knowledge training, as well as the initial explanation of the

job procedure, may be best done in an office/classroom setting; especially when noise levels,or other conditions at the job site, make communication difficult. A complete series of jobsteps could be presented through the use of slides developed at the mining operation.

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ON-THE-JOB TRAINING MODULESFOR THESAND, GRAVEL, AND CRUSHED STONE INDUSTRY

PLANT SHUT-DOWN

For the job of plant shut-down, this module describes basic job steps, potential accidents andhazards, and recommended safe job procedures.

The job of plant shut-down is usually done by the plant operator, but may be done by otheroccupations, such as utility worker, laborer, etc. The plant operator/utility worker must makesure that employees, and others, are protected from accidents and injuries that could resultfrom plant shut-down operations.

Remember to observe two key precautions during normal plant shut-down:

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SEQUENCE OF

BASIC JOB

STEPS

3. Stop allconveyors,

stackers, andassociatedequipment, inplant sequence.

(Note to trainer:review yourplants shut-down procedurein detail.)

4. Stop secondarypumps.

POTENTIAL

ACCIDENTS OR

HAZARDS

3. A) Leaving materialson, or in,

equipment, whichcan cause start-up problems forthe next shift (beltslippage, motoroverload, etc.)

B) Material pile-upand spillage attransfer points.

4. A) Slipping/falling.


PROCEDURES

3. A) Be sure there is nomaterial remaining on,

or in, each piece ofequipment beforeshutting it off.

B)After primary feedsystem is off, shut-downsequence usuallybegins with the primarybelt from hopper, orsurge pile, andproceeds to the finishedproduct belts (suggestwritten sequence and

labeled switches fortraining and referencepurposes). Look, wherepossible, to ensure thateach piece ofequipment has actuallystopped before shuttingoff the next piece ofequipment.

4. A) Use designatedwalkways, and examinethem for wet or icyconditions, and fortripping hazards.

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SEQUENCE OFBASIC JOB

STEPS

5. Stop primarypumps.

POTENTIAL

ACCIDENTS OR

HAZARDS

B) Electrical hazards(exposed wires,

frayed insulation,etc.)

C) MechanicalHazards.


PROCEDURES

B) Check for electricalhazards, especially if

on/off switch is at pump.

C) Check for mechanicalhazards, especially ifon/off switch is at pump.Correct or report anyhazards.

5. A) Wear life jacket.

B) Use designatedwalkways, and examinethem for wet or icyconditions, and fortripping hazards.

C) Examine work area forelectrical hazards.

D) Examine work area forin-place guards.

5. A) Falling into water.

B) Slipping/falling.

C) Electricalhazards.

D) Mechanicalhazards.

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GENERAL INFORMATION









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MODULE NUMBER 4OFINSTRUCTION GUIDE NO. 40


PLANT OPERATION

For the job of plant operation, this module describes the basic job steps, potential hazardsand accidents, and the recommended safe job procedures.

These job steps are usually done by the plant operator, and other occupations, such as utilityworker, laborer, etc. The plant operator/utility worker must make sure that employees, andothers, are protected from accidents and injuries resulting from plant operations.

While both sand and gravel plants, and crushed stone plants, are built by many differentmanufacturers, the processes and equipment involved in the production effort are very similar.

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SAND AND GRAVEL PLANTS

At a typical sand and gravel plant, raw material from a hopper at a dumping station is carriedby conveyor belt to a screening deck. The screening deck removes oversized material (largeclay balls, roots, very large rocks, etc.), separates sand from gravel, and then separates thegravel into different sizes. Spray bars wash the gravel as it passes through the screening

deck.

Large stones then go to log washers, while medium size material (chat and/or pea gravel)goes to a screw. The large stones, after emerging from the log washer, and the finer material,after emerging from the screw, pass through separate final rinse stations on the way tostorage areas. Transportation to a storage area may be by a fixed conveyor system, a radialstacker system, or an extendable belt conveyor system. A radial stacker is a conveyor system,that rotates from a stationary pivot point and stores the material in an arc-shaped stockpile.The extendable belt conveyor system has the capability of lengthening or shortening itself bymoving the head section. The head section is mounted on wheels and moves on rails, whichallows the conveyor to supply several stockpiles, hoppers, or silos.

Sand, after being separated on a screening deck, flows to a classifier, where it is washed andsized. The sand is then carried by a screw, which separates the sand from the water, to aconveyor belt, which carries the sand to a storage area.

Water, that is used in the plant, is pumped from a fresh water pond. After use, the dischargedwater is pumped into a settling pond.

CRUSHED STONE PLANTS

A crushed stone plant differs somewhat from a sand and gravel plant. Raw material, ofvarious sizes, is brought from a quarry, to a primary crusher, by haul units. Some primarycrushers are fed by wobblers, which are chain driven conveying systems, with eccentricrollers.

After primary crushing, material is conveyed by belt to a scrubber for washing. The scrubberis a cylindrical rotary device with internal screens, and auger-type vanes that carry thematerial through the scrubber. Very fine material is separated from coarse material in thescrubber. The very fine material is sent to a settling pond. Coarse material is sent first to asurge pile, and then to a primary screening deck. Oversized material is carried from theprimary screening deck to a secondary crusher, and is then returned to the primary screeningdeck to be separated into desired sizes. A crushed stone plant contains a series of screendecks, secondary crushers, and final rinse screening stations. The finished product travelsthrough a final rinse stage, and is then stored in silos, bins, and stockpiles.

A sand and gravel, or crushed stone, plant consists of a number of interdependent productionprocesses, which occur simultaneously. Therefore, it is important to know how the plantoperates, in order to prevent a massive pile-up of material at transfer points during plant start-up, operation, or shutdown.

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PRE-SHIFT INSPECTIONS

Before initial operation on production runs, a careful and detailed inspection of the plant, andall of its components, should be conducted. Check the alignment of all mechanicalcomponents. Also, check the operating alignment of the belts on the carrying rollers and thereturn idlers. Visually inspect the belts for defective splices. Be sure that all moving partshave guards in place.

Check that there are no construction materials, tools, or projecting members that can rub,tear, or cut the belt when it is started. Be sure that chute skirtboards are intact, and are nottouching the belt. Adjust rubber edging strips on skirtboards, so that they touch lightly on thebelt surface. Adjust belt scrapers, if necessary.

WALK-THROUGH INSPECTIONS

Walk through the plant soon after it has started. Listen for any unusual sounds made byidlers, pulleys, shafts, bearings, drives, bolts, and belt splices.

Walk-through inspections of all plant equipment should be made several times each day,during the operating shift. Guards, safety devices, and warning signs should be checkedto determine that they are in proper position, and in good working order. Only competent,properly trained, and authorized persons should repair defective safety devices.

Although a stuck idler may not appear to be important, plant operators should realize that,if an idler is stuck under a high-speed belt that is handling abrasive material, the shell ofthe idler will soon wear through, causing a knife edge that will severely damage anexpensive belt. Plant operators should be alert for impending idler failures, and correct themalfunction before the belt is damaged.

LUBRICATION AND REPAIR

A comprehensive lubrication program is essential to attain low maintenance costs, anddependable plant operations. Pay particular attention to lubrication of all bearings. Equipmentlife will be extended by following the manufacturers recommendations for types of lubricant,amount and frequency of application, and type of greasing equipment to be used.

People can become entangled in moving parts while lubricating equipment. Extended greasefittings and hoses allow moving equipment to be safely lubricated. Equipment must be shutdown and locked out, if lubrication requires either the removal of guards or the placement of

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people in dangerous positions to perform the job.

Frequently used repair parts should be stocked at the plant site to maximize plantdependability and productivity, and to minimize maintenance costs and downtime.

Since plant equipment operates automatically after start-up, plant operation under normal

conditions consists primarily of inspection, maintenance, and clean-up.

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The following safe job procedures will help to minimize incidents which may cause injuries,and adversely affect production.

REQUIRED OR RECOMMENDED EQUIPMENT:HARD HAT, STEEL-TOED SHOES, LIFE JACKET, HEARING PROTECTION, SAFETY

SEQUENCE OF

BASIC JOB

STEPS

1.A) Visuallyinspect Vbelts.

2.A) Visuallyinspectconveyorbelt idlers,belt splices,

and stopcord. Listenfor noisy,defectivebearings.

GLASSES

POTENTIAL ACCIDENTS RECOMMENDED SAFE JOB

OR HAZARDS PROCEDURES

1. A) Slipping/falling. 1. A) Use designated walkways,and keep them clean, andclear of stumbling hazards.

B) Mechanical hazards B) Make sure guards are in(body or clothing place and adequate, andcaught in that clothing fits snugly.machinery).

2. A) Slipping/falling. 2. A) Use designated walkways,

B) Mechanical hazards(body or clothingcaught inmachinery).

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and keep them clean, andclear of stumbling hazards.

B) Make sure guards are inplace and adequate, andthat clothing fits snugly.Do not touch idlers.

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SEQUENCE OF

BASIC JOB

STEPS

5. Check if guardis in place atpower drive thatmoves radialstacker. (Note

to trainer: Omitif radial stackeris not used, andadd what isused.)

POTENTIAL ACCIDENTS

OR HAZARDS

C) Getting shovelcaught in return

idlers.

D) Striking co-workers.

E) Back injuries.

F) Caught betweenmoving radialstacker andstationary object, ifstacker begins tomove.


PROCEDURES

C) When shoveling ontomoving conveyor, always

shovel in the direction thatthe belt is traveling - theshovel and any material willbe carried away from you ifthe shovel becomes hungin the belt.

D) Watch out for other peoplein the area.

E) While shoveling, moveyour feet when turning,

rather than twisting yourbody. Lift with your legs,not your back. Load yourshovel moderately.

F) When working near tailpulley of a radial stacker,do not position yourselfbetween tail pulley andstationary object. If yourconveyor system is

equipped with an audiblealarm, immediately moveaway from belt if alarmsounds.


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SEQUENCE OF

BASIC JOB

STEPS

6.A) Visuallycheckscreens forproblems

with decks,V belts,leakingbearingseals,pluggedspray bars,etc. Reportanyproblems.

7.A) Inspect gearreducers atthe conveyor

headsection.

POTENTIAL ACCIDENTS

OR HAZARDS

B) Mechanical hazard.


PROCEDURES

B) If guard is not in place, donot touch drive. Report to

supervisor, or replaceguard by first locking outand tagging power to motordrive. Restore power afterguard is replaced.


B) Mechanical hazards. B)Visually check that guardsare in place and adequate,and that clothing fitssnugly. Do not touch anyexposed moving parts.Report missing guards.

7. A) Burned hand from 7. A) Visually check gearhot reducers. reducers to determine if

there is any wobble in main

shaft. Listen to determineif gear reducers arewobbling or making anyother unusual noise.Report any problems.

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SEQUENCE OF

BASIC JOB

STEPS

8.A) Visuallyinspect log

washers(whereused).

9. Inspect sandclassifier (whereused).



8. A) Slipping/falling. 8. A) Use designated walkways,and keep them clean, and

clear of stumbling hazards.

B) Mechanical hazards. B) Visually check that guardsare in place and adequate,and that clothing fitssnugly. Do not touch anyexposed moving parts.Report missing guards.

9. A) Slipping/falling from 9. A) Check for material build-upmaterial spilled onwalkway.

B) Struck by whippingwater hose.Slipping/falling whilehandling clean-uphose.

C) Electrocution.

D) Eye injuries.

E) Bruises from waterstream.

F) Knocked intosomething.

where stations dump intosplitting troughs. Cleanspilled material with awater hose.

B) Secure hose againstwhipping by having asecure grip, standing onhose near nozzle, or usinga helper. Turn water on

slowly to a pressure atwhich you are able to walk.

C) Do not aim water at anyelectrical boxes.

D) Wear eye protection. Beaware of others working inarea.

E) Do not aim water hose atanother person.

F) Do not stand with yourback toward openstairways, walkways, ormoving equipment.

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SEQUENCE OF

BASIC JOB

STEPS

10. Inspect gearboxes at sand

screws (whereused). Listenfor unusualnoise in gearboxes, andreport anyproblems tosupervisor.

11. Inspect rock

crusher (whereused), andclean up anyspillage with ashovel and/or awater hose.



10. A) Slipping/falling. 10. A) Use designated walkways,and keep them clean, and

clear of stumblinghazards.

11. A) Slipping/falling 11. A) Use designated

from materialspilled on walkway.

B) Struck by whippingwater hose.Slipping/fallingwhile handling

clean-up hose.

C) Electrocution.

D) Eye injuries.

E) Bruises from waterstream.

F) Knocked intosomething.

walkways, and keep themclean, and clear ofstumbling hazards.

B) Secure hose againstwhipping by having asecure grip, standing onhose near nozzle, or using

a helper. Turn water onslowly to a pressure atwhich you are able towalk.

C) Do not aim water at anyelectrical boxes.

D) Wear eye protection. Beaware of others working inarea.

E) Do not aim water hose atanother person.

F) Do not stand with yourback toward openstairways, walkways, ormoving equipment.

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SEQUENCE OF

BASIC JOB

STEPS

12. Return to workstation. Listenfor any unusualsounds whilereturning to

work station.Periodicallywalk plantarea, as calledfor by companypolicy.

POTENTIAL ACCIDENTS

OR HAZARDS

G) Finger caughtbetween pulley and

belt.

12. A) Tripping/slippinghazards.


PROCEDURES

G) Check that all V beltdrives and couplings are

guarded. Do not touchV belts. Report anymissing guards tosupervisor.

12. A) Watch step, and removeany tripping hazards whiletraveling to work station.

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GENERAL INFORMATION









training. Any general theory, or knowledge training, as well as the initial explanation of thejob procedure, may be best done in an office/classroom setting; especially when noise levels,or other conditions at the job site, make communication difficult. A complete series of jobsteps could be presented through the use of slides developed at the mining operation.

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ON-THE-JOB TRAINING FOR THESAND, GRAVEL, AND CRUSHED STONE INDUSTRY

MAINTAINING CONVEYOR SYSTEMS

For the job of conveyor operation and maintenance, this module describes the basic jobsteps, potential accidents and hazards, and recommended safe job procedures.

This job is usually done by the plant operator and maintenance personnel, but it may be doneby other occupations, such as utility worker, laborer, etc. The plant operator and maintenancepersonnel must make sure that employees, and others, are protected from accidents andinjuries resulting from conveyor maintenance.

Conveyor systems used at sand, gravel, and crushed stone operations are very similar,although the systems are built by many different manufacturers. Each conveyor system hasits own performance requirements, design features, and operating environment. Thesespecial situations have to be considered in order to establish safe and efficient operating andmaintenance procedures. Conveyor manufacturers can often assist in developing these

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procedures.

Many conveyor systems perform well with as few as one or two operators. Conveyorperformance can be continuously monitored by electrical controls, safety sensors, closedcircuit television, signal systems, and other devices.

Modern electrical controls use programmable controllers, or computers, to measure conveyorbelt performance. Electrical controls can also be used to weigh, mix, and blend material, aswell as to switch material flow paths. Sensors, and other devices used to indicatemaintenance requirements and other unsafe conditions, are integral parts of some electricalcontrol systems. These controls, sensors, and other devices are highly durable. Typically,they can only be maintained and serviced by specialists.

CONVEYOR ACCIDENTS AND DAMAGE PREVENTION

INTRODUCTION

Conveyor accidents that cause personal injuries do not normally occur because of faultyequipment design or component failure. These accidents are usually caused by human error,inadequate training, or lack of hazard awareness.

Employees should receive safety training, after the conveyor is designed and the system isinstalled by qualified personnel. Supervisory, operating, and maintenance personnel shouldbe instructed in safe operating procedures, hazard recognition, and housekeeping skills.Periodic refresher training should be given in these subjects. Unauthorized employees shouldnot be permitted to enter hazardous areas.

All workers - especially maintenance personnel - should be provided with proper tools and

equipment to operate, and maintain, the conveyor in a safe condition.

COMMON ACCIDENTS

One common type of accident involving conveyors occurs when an employee stops aconveyor to perform work on it, but does not properly lockout and tag the electrical controls.

Another employee, noticing that the belt is stopped, restarts it - injuring the employee that isperforming the work.

Another common accident involving conveyors occurs when an employee becomes caught

in unguarded, or inadequately guarded, moving equipment. The guards may not have beeninstalled, or, more commonly, the guards may have been removed to perform work. Also,the guards may have been previously removed and not replaced. Employees should be surethat equipment guards are properly installed and maintained.

DAMAGE PREVENTION

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The belt is the most expensive item in a conveyor system. Therefore, proper belt operation,and belt maintenance, are particularly important in order to minimize repair and replacementcosts.

Weather can affect belt operation. In sub-zero temperatures, special lubricants are

sometimes necessary in order to avoid overloading the drive motor. The belt may sometimesbe covered with moisture, frost, or frozen material. A belt scraper, installed just ahead of thepoint where the belt goes onto the drive pulley, may be useful for removing frost, or frozenmaterial, that is stuck to the belt. Operating the belt for a brief period, at start-up, beforeloading it, may be advisable, in order to remove frost or frozen material.

Sticky or frozen material on pulleys or idlers can cause belt misalignment, or other damage.Pulley scrapers, and/or soft rubber pulley lagging, may help to correct this condition. No oneshould be allowed to remove stuck material from the belt, unless the belt is stopped and themaster electrical control is locked out and tagged.

Belts can be damaged, or prematurely worn, if loaded with improper sizes or volumes ofmaterial. Foreign objects, such as tramp iron, spikes, or timbers, in the material flow can jamthe belt, causing expensive shut-downs and repairs.

Stuck idlers, under a high speed belt, can wear through to a knife edge that can severelydamage a belt. Plant operators should be alert for impending idler failures, and correctmalfunctions before the belt is damaged.

SAFETY PRECAUTIONS

The following safety precautions are generally applicable to conveyor systems:

1. Conveyors should only be used to handle material for which they were designed.

2. Belt capacity, and belt speed design ratings, should not be exceeded.

3. Only trained personnel should be allowed to operate conveyor systems. Operatorsshould have complete knowledge of conveyor operation, electrical controls, safetydevices, and warning devices, and the capacity and performance limitation of theconveyor system.

4. All personnel should know the location and operation of all emergency controls andsafety devices. Areas near emergency controls and safety devices must be kept free ofobstructions at all times.

5. All equipment must be inspected at the beginning of the shift, before the equipment isstarted. Guards, safety devices, and warning signs should be maintained in properpositions and in good working order. Only competent and properly trained and authorized

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persons should adjust and repair safety devices.

6. Another walk-through inspection should be made after the plant is started, in order todetect any problems with idlers, pulleys, shafts, bearings, drives, bolts, or belt splices.Listen for unusual sounds.

7. Poking at, or prodding, material on the belt, or any component of a moving belt, must beprohibited.

8. Contact with, or work on, a conveyor must occur only while the equipment is stopped, andthe electrical control is properly locked out and tagged out.

9. People must not ride on, step on, or cross over a moving conveyor, except at designedcross-overs.

10. People should only walk, or climb, on conveyor structures by using the walkways, stairs,ladders, and cross-overs that are provided.

11. Good housekeeping is a prerequisite for safe conditions. All areas around a conveyor,particularly those areas around drives, walkways, safety devices, and control stations,should be kept free of debris or any other obstacles. Any posted warning signs orinstructions should be kept current.

12. Conveyors that are in an unsafe condition for operation, or that do not have all guardsand safety devices in good condition, must not be used until all necessary repairs havebeen made.

13. All people should be barred, by appropriate means, from entering an area where falling

material may present a hazard. Warning signs and barricades can be used.

14. First-class maintenance is a prerequisite for the safest conveyor operation. Maintenance,including lubrication, must be performed with the conveyor power locked-out and tagged.Special lubricating equipment, lube extensions, pipes, etc., can be installed so thatlubrication of an operating conveyor can be done without any hazards.

CONVEYOR SYSTEM MAINTENANCE

An equipment maintenance program includes the tasks of inspection, housekeeping,lubrication, and repair.

During inspections, check the alignment of all mechanical components, and the operatingalignment of the belt on carrying and return idlers. Make sure there are no repair or

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construction materials, tools, or projecting members that can rub, tear, or cut the belt whenit starts up. Check that chute skirtboards are intact, and are not touching the belt. Adjustrubber edging strips on skirtboards so that the strips touch only lightly on the belt surface.Check and adjust belt scrapers, if necessary.

Good housekeeping is essential for dependable operation and low cost maintenance. Built-

up material on the deck can rub against, and eventually stop, idlers, thereby increasing belttension and possibly damaging the belt. Spillage on the return belt can also damage the belt,as lumps of material are squeezed between the belt and pulleys. Scrapers on the return belt,where the belt enters the tail pulley, may be desirable in some cases.

A comprehensive lubrication program is essential for low maintenance costs and dependableconveyor operation. Pay particular attention to the lubrication of all bearings. Equipment lifewill be extended by following the manufacturers recommendations for the type of lubricant,amount and frequency of application, and type of greasing equipment to be used.

Frequently used repair parts should be stocked at the plant site, in order to maximize plant

dependability and productivity and minimize maintenance costs and downtime.

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The remainder of this module covers safe job procedures for seven conveyor maintenancetasks. Following these procedures will help to minimize incidents which can cause injuries,and adversely affect production.

REQUIRED AND/OR RECOMMENDED PERSONAL PROTECTIVE EQUIPMENT:

HARD HAT, STEEL-TOED SHOES, GLOVES, SAFETY GLASSES WITH SIDESHIELDS, OR GOGGLES, HEARING PROTECTION.

I. LACING CONVEYOR BELTS

SEQUENCE OF

BASIC JOB STEPS1. De-energize and

lockout and tagbelt power.Mechanicallyblock belt fromrolling withoutpower.

POTENTIAL ACCIDENTS

OR HAZARDS1. A) Electrical hazard -

face of breakercoming open andallowing contact withenergized parts.

B) Mechanical hazard -power turned on due

to improper lock-outprocedure whileworking onequipment.

xxxix


PROCEDURES1. A) Stand on non-conductive

mat. Wear gloves.

B) Never work on equipmentunless you have locked-

out power. Each persondoing work must lockoutand tag. Each personmust keep their key intheir possession. Confirmthat proper equipmentwas locked-out by testingstart switch.

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SEQUENCE OF

BASIC JOB STEPS

2. Select tools andsupplies:

1. Two comealongs

2. Impactwrench

3. Hole punch4. Two belt

clamps5. Utility knife6. Straight

edge7. 5'x2"x10"

board

8. Template9. Nails10. Stud

breaker11. Laces

3. Check/inspecttools andworkplace.Ensure thatcounterweight isimmobilized.

POTENTIAL ACCIDENTS

OR HAZARDS

2. A) Strains from liftingtools.

B) Cuts from handlingcable.

C) Cuts from utilityknife.

3. A) Injury due to cable orchain break.


PROCEDURES

2. A) Use proper bending andlifting technique by usingknees and legs rather

than back.

B) Wear gloves, and watchfor broken wires in cable.

C) Wear protective gloves,and make sure knife isproperly sheathed.

3. A) Inspect cable or chain.Repair/report if damaged.

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SEQUENCE OF

BASIC JOB STEPS

4. Attach belt clampsto each end of beltabout 3 feet backfrom place to bespliced. Insert beltbetween theclamps, and

tighten bolts.

5. Attach both comealongs to beltclamps, using twoholes in eachclamp.

POTENTIAL ACCIDENTS

OR HAZARDS

B) Shock from electricalimpact wrench.

C) Slips/falls.

4. A) Falling off conveyorbelt to ground.

B) Pinched fingers.


PROCEDURES

B) Inspect impact wrench fordamage and wear oncase and insulation of

wires. Inspect impactwrench for three prongplug, or other means ofgrounding, or a doubleinsulated case. Dry dampequipment - clean greasyequipment. Do not standin water or on dampsurfaces if possible - wearrubber boots if needed.

C) Remove slipping/trippinghazards.

A) Use approved manlift ifnecessary for safeaccess. You must use fallprotection if you areworking in an elevated,exposed position.

B) Keep fingers clear ofpinch points.

5. A) Cuts or scratches 5. A) Inspect cables. Weardue to burrs or gloves, and do not slidebroken strands. hands along cable.

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SEQUENCE OF

BASIC JOB STEPS

6. Use the straightedge and utilityknife to cut the

torn edge away.

7. Draw two edgestogether withcome-along,checking progressperiodically, toobtain desiredtension.



6. A) Cuts. 6. A) Use a retractable bladeknife. Cut away from, orbeside, your body - never

cut toward yourself. Keepa firm grip on tools. Donot try to cut through beltwith only one cut - makeseveral cuts until knifegoes through. Use sharpblades.

B) Knife dropped on B) Place warning barricadepeople below. below.

7. A) Cable or chain 7. A) Stand to the side and facebreaking. away from come-along

while operating thehandle. If conveyor doesnot have gravity, or othertype, take-up pulley,loosen tail pulley, and pullforward as much asnecessary.

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SEQUENCE OF

BASIC JOB STEPS

8. Splice belt.1. Slide the 5'

- 2x10

board undersplicer.

2. Settemplate ontop of beltand drivethe 6 pennynailsthroughboard.

3. Connecthole punchto impactwrench.

4. Drill out allholes.

5. Removenails andtemplate.

6. Insert bolts.7. Tighten

bolts from

middle toeachoutsideedge, topreventbuckle.

8. Break offexcess studlength bybendingstuds

parallel tobelt withstudbreaker.



8. A) Falling off conveyor. 8. A) You must use fallprotection when workingfrom elevated positions.

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SEQUENCE OF

BASIC JOB STEPS

9. Loosen comealongs, andremove.

10. Remove clamps.

11. Realign andtension tailpulley, ifpreviouslyloosened.

12. Remove anymechanicalblocks. Removeyour lock-out andtag. Restorepower.

POTENTIAL ACCIDENTS RECOMMENDED SAFE JOB OR HAZARDS

9. A) Struck by handle.

10. A) Fall off conveyor.

B) Bruised knuckles.

11. A) Cut knuckles.

12. A) Persons caught inconveyor.

PROCEDURES

9. A) Grip handle firmly, flipsafety latch to reverse,and stroke handle full

stroke in both directions.

A) You must use fallprotection if you areworking in an elevated,exposed position.

B) Wear gloves, and griptools firmly.

11. A) Wear gloves. Keep firmgrip on tools.

12. A) Check that everyone isclear of equipment.

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II. CHANGING BEARINGS ON CONVEYORS

SEQUENCE OF

BASIC JOB STEPS

1. Lockout and tagbelt power.

2. Select tools andsupplies:

1. Ratchet andsockets

POTENTIAL ACCIDENTS

OR HAZARDS

1. A) Electrical hazard -face of breakercoming open andallowing contact withenergized parts.

B) Mechanical hazard -power turned on dueto improper lock-outprocedure while

working onequipment.

2.A) Strains from liftingtools.

2. A come-along3. Replacement

bearing4. Burlap bag

and hammer5. Cutting torch6. Emery cloth7. Grease

B) Cuts from handlingcome-along cable.


PROCEDURES

1. A) Stand on non-conductive mat. Weargloves.

B) Never work onequipment unless youhave locked-out power.Each person doing work

must lockout and tag.Each person must keeptheir key in theirpossession. Confirmthat proper equipmentwas locked-out bytesting start switch.

2.A) Use proper bendingand lifting technique by

using knees and legsrather than back.

B) Wear gloves, andwatch for broken wiresin cable.

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SEQUENCE OF

BASIC JOB STEPS

6. Loosen the bearingby removing bolts.

7. Take up slack torelieve pressure onbearing.

8. Remove bearing.

9. Install new bearing.Buff shaft withemery cloth.

Grease shaft lightly.Line up bearingwith come-along.

POTENTIAL ACCIDENTS

OR HAZARDS

6. A) Bruised knuckles.

7. A) Cable breaking.

8.A) Metal in eyes.Piece of metal inhand.

B) Hazards with cuttingtorch, if bearingmust be cut awayfrom shaft.

9.A) Cuts, bruisedknuckles.


PROCEDURES

6. A) Use tools properly.

7.A) Stand to the side, andface away from come-along while operatingthe handle.

8.A) If bearing is frozen,wear goggles andgloves, and cover the

bearing with a burlapbag (or somethingsimilar). Knockhousing away fromrace with a hammer.

B) Wear goggles or faceshield. Check thattanks are secure, andequipment is in goodworking order. Checkthat work area is clearof extraneouscombustible material,and that fireextinguisher isavailable.

9.A) Wear gloves. Useproper tools in propermanner.

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SEQUENCE OF POTENTIAL ACCIDENTS RECOMMENDED SAFE JOB

BASIC JOB STEPS OR HAZARDS PROCEDURES

10. Restore power. 10. A) Person caught in 10. A) Make sure peopleconveyor. are clear of belt.

Remove lock and tag

from switch.

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III. REPLACING V BELTS

SEQUENCE OF BASIC

JOB STEPS

1. Lockout and tag beltpower.

2. Remove guard. Holdguard securely if it couldfall when disconnected.Get help when removingvery large guards.

3. Loosen theadjustments.

POTENTIAL ACCIDENTS

OR HAZARDS

1. A) Electrical hazard -face of breakercoming open andallowing contact withenergized parts.

B) Mechanical hazard -power turned on dueto improper lock-outprocedure whileworking onequipment.

2. A) Cuts; bruisedknuckles.

B) Tripping; foot injury.

3. A) Wrench slipping offand injuring hand.

RECOMMENDED SAFE

JOB PROCEDURES

1. A) Stand on non-conductive mat.Wear gloves.

B) Never work onequipment unlessyou have locked-outpower. Each persondoing work mustlockout and tag.Each person mustkeep their key intheir possession.Confirm that properequipment waslocked-out by testingstart switch.

2. A) Use proper tools inthe proper manner.Wear gloves.

B) Place guard, bolts,etc., out of the way.

3. A) Use proper tools inthe proper manner.

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SEQUENCE OF BASIC

JOB STEPS

4. Remove old belts.

5. Install new belts.

6. Replace guard andrestore power.

POTENTIAL ACCIDENTS

OR HAZARDS

4. A) Pinched finger.

5. A) Pinched finger.

6. A) Mechanical hazard.

RECOMMENDED SAFE

JOB PROCEDURES

4. A) If necessary, cut oldbelt, or use tool topry belt off.

5. A) If necessary, use atool to carefully prynew belt onto pulley.

6. A) Make sure guard isreinstalled properly.Make sure people

are clear of belt, andremove lock and tag.

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IV. TRAINING CONVEYOR BELTS

SEQUENCE OF BASIC

JOB STEPS

1. Install idlers.

2. Determine which idlersneed adjusting bywatching moving belt.

3. Lockout and tag powerswitch in off position.

4. Prepare to adjust idlersby loosening the

mounting bolts onseveral idlers upstreamof the location wherethe belt is running toone side.

5. Restore power to belt.

POTENTIAL ACCIDENTS RECOMMENDED SAFEOR HAZARDS

1. A) Falling fromconveyor.

2. A) Mechanical hazard.Particles in eyes.

3. A) Mechanical hazard.

4. A) Wrench slipping -injuring hand.

5. A) Mechanical hazard.People caught inbelt.

JOB PROCEDURES

1. A) If there is apossibility of falling,use a safety belt andline.

2. A) Do not touch movingbelt or idlers. Wearsafety glasses with

side shields, orgoggles.

3. A) Properly lockout andtag power.

4. A) Use tools in propermanner. Wear

gloves.

5. A) Make sure peopleare clear of belt, andremove lock and tag.

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SEQUENCE OF BASIC

JOB STEPS

6. Adjust idlers by tappingone end of idler supportstands, with hand

sledge, in the directionthat will draw belt backtoward center of idlers.

7. Lockout and tag power.

8. Tighten mounting boltson adjusted idlers.

9. Restore power.

POTENTIAL ACCIDENTS

OR HAZARDS

6. A) Flying objects (rust,dirt, etc.)

B) Mechanical hazards.

7. A) Mechanical hazard.People caught inbelt.

8. A) Wrench slipping -injuring hand.

9. A) Person caught inconveyor.

RECOMMENDED SAFE

JOB PROCEDURES

A) Wear gloves andeye protection.

B) Lockout and tagpower whenever it isnecessary to enter aguarded area, or toreach underconveyor.

7. A) properly lockout andtag power.

8. A) Use tools in propermanner. Weargloves.

9. A) Make sure peopleare clear of belt, andremove lock and tag.

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VI. INSPECTION OF HEAD AND TAIL PULLEY BEARINGS

SEQUENCE OF BASIC POTENTIAL ACCIDENTS RECOMMENDED SAFE

JOB STEPS

1. Inspect bearings, 3-4times weekly, whileconveyor is running.

OR HAZARDS JOB PROCEDURES

1. A) Mechanical hazard. 1. A) Leave guard on -inspect throughguard. Look fororange coloration ofshaft, or shaftwobbling. Look forsmoke.

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VII. GENERAL CONVEYOR MAINTENANCE

SEQUENCE OF BASIC

JOB STEPS

1. Check walkways forsafety hazards.

2. Check belt foralignment. Inspect thelacing and splices.Make sure that allrollers are rolling, andnot making noise.Check skirtboards for

defects. When plant is

POTENTIAL ACCIDENTS

OR HAZARDS

1. A) Trips and falls.

2. A) Mechanical hazards- caught in belt.

not processing material,pull emergency cord tocheck that it functionscorrectly.

3. Grease head and tail 3. A) Mechanical hazardspulley. - caught in pulley.

RECOMMENDED SAFE

JOB PROCEDURES

1. A) Check walkways tobe sure that they arefree of wastematerial, and thatthere are no weakspots. Check thatsteps, handrails,guardrails, andtoeboards are intact,

and have nodamage.

2. A) Only do visualinspections with beltrunning. Do nottouch belt unlesspower is locked-outand tagged.

3. A) Only grease whenpower is locked-outand tagged, unlesspulleys are equipped

with extendedgrease fittings.

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GENERAL INFORMATION

This module is part of an Instruction Guide that was developed to assist the sand, gravel, andcrushed stone industry in conducting effective on-the-job training (OJT) of new employees,or employees reassigned to different jobs. The use of training materials, such as this module,

is an important part of an effective, systematic, OJT program.


Recommendations for an overall OJT program are contained in the Mine Safety and Health

Administration (MSHA) guide: Structuring Effective On-The-Job Training Programs






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ACCIDENT AND DAMAGE PREVENTION

Normally, accidents that cause personal injury are not the result of faulty design or componentfailure. They are usually caused by human carelessness, inadequate training in operations,

or lack of awareness of possible hazards.

Operating and maintenance personnel, and their supervisors, should be initially, and thenperiodically, instructed in safe operating procedures, recognizable hazards, precautions, andmaintenance of a safe work place. Operating and maintenance personnel should also beprovided with the proper tools and equipment to operate, and maintain, plant equipment ina safe condition. Maintenance personnel should receive training in the value and conduct ofa comprehensive preventive maintenance program. Employees, who do not have propertraining, must not be allowed to enter hazardous areas.

PRE-SHIFT INSPECTIONS

Before initial operation on production runs, a careful and detailed inspection of the plant, andall of its components, must be conducted. Check alignment of all mechanical components.

Also, check the operating alignment of the belts on the carrying and return idlers, and visuallyinspect belts for defective splices. Be sure that all moving parts have guards in place.

Check to see that there are no construction materials, tools, or projecting members that canrub, tear, or cut the belt when it is started. Be sure that chute skirtboards are intact, and nottouching the belt. Adjust rubber edging strips on the skirtboards, so that they touch lightly onthe belt surface. Adjust belt scrapers, if necessary.

WALK-THROUGH INSPECTIONS

Walk through the operating plant soon after it is started. Listen for any unusual sounds madeby idlers, pulleys, shafts, bearings, drives, bolts, and belt splices.

Walk-through inspections of all plant equipment should be made several times each day,during operating shifts. Guards, safety devices, and warning signs should be checked, inorder to determine that they are in proper position and in good working order. Onlycompetent, properly trained, and authorized persons should repair defective safety devices.

LUBRICATION AND REPAIR

A comprehensive lubrication program is essential for low maintenance costs and dependableplant operations. Pay particular attention to lubrication of all bearings. Equipment life can beextended by following manufacturers recommendations for types of lubricant, amount andfrequency of application, and type of greasing equipment to be used.

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People can become entangled in moving parts while lubricating equipment. Extended greasefittings, and hoses, allow the safe lubrication of moving equipment. Equipment must be shutdown, and locked-out, if lubrication requires either the removal of guards, or people placingthemselves in potentially dangerous positions to perform the job.

The remainder of this module covers safe job procedures for two repair and maintenancetasks. Repair and maintenance of conveyor belts is covered in Module 5 of this InstructionGuide. These procedures will help to minimize incidents which may cause injuries andadversely affect production.

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REQUIRED AND/OR RECOMMENDED PERSONAL PROTECTIVE EQUIPMENT:HARD HAT, STEEL-TOED SHOES, GLOVES, SAFETY GLASSES OR GOGGLES,

HEARING PROTECTION

I. REPLACING SCREENS

SEQUENCE OF

BASIC JOB STEPS

1. Positively identifyequipment to belocked out.Properly shutdown anddeenergizeequipment.Lockout and tagpower in the offposition.

2. Select tools andsupplies.

3. Check/inspecttools andworkplace.

POTENTIAL

ACCIDENTS OR

HAZARDS

1.A) Mechanicalhazard - caughtin, or struck by,equipment.

2.A) Strains fromlifting.

3.A) Cable or chainbreak injuringpersonnel.

B) Shock fromelectrical impactwrench.

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PROCEDURES

1.A) Never work on equipmentunless you have locked outpower. Each person doingwork must lockout and tag.Each person must keep theirkey in their possession.Confirm that properequipment was locked outby testing start switch.

2.A) Use proper bending andlifting technique by usingknees and legs rather thanback.

3.A) Inspect cable or chain.Repair or report if damaged.

B) Inspect impact wrench forthree-prong plug, or othermeans of grounding; or adouble insulated case.Check that cord is not frayedor damaged. Dry dampequipment.

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SEQUENCE OF

BASIC JOB STEPS

4. Wash front partof screen, anduse come-alongto pull coverback.

5. Replace screens.

6. Restore power toscreen.

POTENTIAL

ACCIDENTS OR

HAZARDS

C) Slips and falls.

4. A) Dirt in eyes.

B) Cuts on handfrom burrs oncable.

5. A) Falling throughopening in chutebox.

B) Back injury.

6.A) Person caught in,or struck by,screen deck.

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PROCEDURES

C) Remove slipping and tripping

hazards from walkways andwork areas.

4. A) Wear eye protection. Washfront part of screen to cleanmaterial out before pullingcover back.

B) Wear gloves. Do not slidehand along cable.

5.A) Cover opening in chute boxwith a used screen, and/oruse fall protection.

B) Use proper lifting andhandling methods for toolsand screens.

6.A) Remove lock and tag, andmake sure that area is clearof people. Sound start-upwarning alarm if provided.Stand to side, and face awayfrom breaker box whenthrowing switch.

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II. CHECKING AND GREASING SHAKERS

SEQUENCE OF

BASIC JOB STEPS

1. Inspect shakersdaily at end ofshift. Checkscreens for holes.Visually check forworn or stretchedbelts. Check formissing wedges.

2. Grease shakersdaily, or weekly.

POTENTIAL

ACCIDENTS OR

HAZARDS

1.A) Mechanicalhazard.

2. A) Slips and falls.

B) Mechanicalhazard.


PROCEDURES

1.A) Do not remove guards, orclimb on or near equipment,unless power is locked outand tagged.

2. A) Keep walkways and workareas clear of extraneousmaterials, snow, ice, etc.

B) Do not remove guards, orclimb on or near equipment,unless power is locked outand tagged.

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GENERAL INFORMATION









training. Any general theory, or knowledge training, as well as the initial explanation of thejob procedure, may be best done in an office/classroom setting; especially when noise levels,or other conditions at the job site, make communication difficult. A complete series of jobsteps could be presented through the use of slides developed at the mining operation.

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WELDING AND CUTTING

This module describes basic job steps, potential hazards and accidents, and recommendedsafe job procedures for welding and cutting.

Welding and cutting is done during repair, or modification, of existing equipment, and duringconstruction of new equipment. Welders must protect themselves, and others, from accidentsand injuries that might occur due to welding and cutting operations.

Welding is essential to the expansion and productivity of mining companies. Welding is oneof the principal means of fabricating and repairing metal products. It is almost impossible toname an industry that does not use some type of welding. Welding is an efficient,dependable, and economical method of joining metal. Gas welding and arc welding are the

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most commonly used methods of welding.

For gas welding, intense heat is generated by the combustion of gas - usually acetylene andoxygen. The welder uses the oxyacetylene equipment to control and direct the heat on theedges of the metal to be joined, while applying a suitable metal filler. The gas welder mayalso do flame cutting, with a cutting attachment and extra oxygen pressure. Flame, or

oxygen, cutting is used to cut various metals to a desired size or shape, or to remove excessmetal from castings. Gas welders need to adjust regulators, select proper tips and filler rods,prepare metal edges to be joined, and properly manipulate the flame and the filler rods.

For arc welding, intense heat is generated by a high amperage electric arc between anelectrode and the metal pieces to be joined. Molten metal from the tip of the electrode isdeposited in the joint, together with molten metal from the edges of the pieces to be joined.This metal solidifies to form a sound, uniform, connection. Arc welders need to properlyselect electric currents, select electrodes, prepare the metal edges to be joined, andmanipulate the electrodes.

Welders are usually classified as skilled or semi-skilled. Skilled welders have the ability toplan, lay out work from drawings or written specifications, and weld all types of joints invarious positions. Skilled welders also have a wide range of technical knowledge involvingproperties of metals, effects of heat on welded structures, control of expansion andcontraction forces, and recognition of welding defects. A skilled welder may be proficient inseveral types of gas and arc welding processes. As a rule, when the quality and strength ofa weld is critical, skilled welders are certified by their employer, a government agency, or aninspection authority, for the particular welding job they are required to perform.

Semi-skilled welders usually do repetitive work which usually does not involve critical strengthrequirements. They usually start on simple production jobs, and gradually work up to higher

levels of skill. They primarily weld surfaces only in upright positions.

Welding equipment should not be used until exact instructions on its operation have beenreceived. Manufacturers recommendations are very important, and should be followed at alltimes. Attempting to operate a piece of equipment without instruction may damage theequipment, or result in serious injury. Welding equipment is safe to use when it is used in theproper manner.

Welding must be done in a well ventilated area. There must be sufficient movement of air toprevent the accumulation of toxic fumes, or the possibility of oxygen deficiency. Adequateventilation is extremely critical in confined spaces, where dangerous fumes and smoke are

likely to collect. Where considerable welding is done, an exhaust system may be necessaryin order to keep toxic gases and fumes within prescribed health limits. An adequate exhaustsystem is especially important when welding or cutting zinc, brass, bronze, lead, cadmium,or beryllium bearing metals. Fumes from these materials are very hazardous to your health.

Sparks, and dangerous ultraviolet and infrared radiation, are generated by any welding orcutting operation. Consequently, suitable clothing and proper eye protection are necessary.

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Sparks may lead to serious burns. Radiation is extremely dangerous to the eyes. Weldersshould know that these dangers exist during any welding operation, and know the safepractices to follow to prevent personal injury.

Sufficient precaution should be taken to ensure that containers, that are to be welded or cut,are safely vented. Accumulated air or gas in confined areas will expand when heated. The

enclosed pressure may build up and cause an explosion. Welding and cutting should not bedone on used drums, barrels, tanks, and other containers, unless they have been thoroughlycleaned of all combustible substances that may produce flammable vapors or gases.Flammable and explosive materials include gasoline, light oil, and non-volatile oils or solidsthat release vapors when heated. Containers of acids that can react with metals to formhydrogen gas must be thoroughly cleaned before welding or cutting.

Containers can be cleaned by flushing several times with water, chemical solutions, or steam.Water cleaning is satisfactory if the substance in the container is readily soluble in water. Forall less soluble substances, containers should be cleaned with a strong commercial causticcleaning compound, or by blowing steam into the container.

Fires often occur as a result of cutting operations, because proper precautions are not taken.Sparks and falling slag can pass through cracks out of sight of the welder. Personsresponsible for welding and cutting should observe the following precautions:

1. Never use a cutting torch where sparks will be a hazard, such as near rooms containingflammable materials - especially dipping and spraying rooms.

2. If cutting is to be done over a wooden floor, sweep the floor clean and wet it down beforestarting the cutting. Provide a bucket or pan, containing water or sand, to catch drippingslag.

3. Keep a fire extinguisher nearby whenever any cutting is done.

4. Whenever possible, perform cutting operations in open areas, so sparks and slag will notbecome lodged in crevices or cracks.

5. If cutting is to be done near flammable materials, and the flammable materials cannot bemoved, suitable fire-resistant guards, partitions, or screens must be used.

6. Practice good housekeeping - reduce any potential for fires and explosions by keepingwork areas clean of combustible and flammable materials.

7. Keep flames, sparks, grease, and oily rags away from oxygen cylinders and hoses.

8. Never do any cutting near ventilating system

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