Now a day's various new plants and construction sites are in progress at various stages. Every setup requires material handling equipments. Industries are forgetting to attend to some of the safety measures that need to be taken care of during use of material handling equipments. Now a day's awareness for safety has increased. Most management now considers safety as an essential part of the operation. They have written their safety manuals but adherence to safety codes and practices is missing.

WHAT IS SAFETY?
S : Sense the difficulty
A : Apply your mind
F : Formulate plan
E : Examine the situation
T : Timely action
Y : Yields good result

WHY INDUSTRIES ARE NOT FOLLOWING SAFETY:

  • Management is not aware of safety
  • No environment for safety.
  • No pressure from trade union to management.
  • Management's priority towards safety is low.
  • Location problem.
  • Need for large capital investment.
  • Power supply interruption.
  • Problems of Small Scale Industries.
  • Avoid safety regulation Act.
  • No storage facility.
  • No trained man power/qualified personnel recruitments.
  • Time factor involvement i.e. no sufficient time being allotted.
  • No periodic inspection is done for equipments.

WHY SAFETY

  • Save Human Life & avoid accidents
  • Improve quality of work
  • Create smooth & healthy atmosphere
  • Reduce time involvement
  • Built confidence internally & externally.
  • Save production cost & Improve productivity.
  • Prevent national loss.
  • Improve economical growth.
  • Healthy atmosphere to society.

In industries various steps are needed for safety monitoring. But we will limit ourselves to the topic allotted, that is,. 'Testing and Inspection of lifting Tools and tackles' The conference's objective is 'Safety Management'. We would like to explain in brief the different types of testing and inspection methods and safety in material handling.

INSPECTION:
Inspection briefly can be defined as examination and verification. All manufacturing industries needs inspection department. Duty of inspection department is to follow the laid down norms for visual, dimensional, material conformity, technical requirements etc. to satisfy the products being designed and its ultimate usage requirements. We are not discussing in depth methodology of various inspection techniques. However we have listed below various checks for safety of material handling.

TESTING:
Testing is also another important area where concentration is emphasized. Normally it is duty of all material handling equipment manufacturers that product should be tested internally before put in practical usage. It is duty of manufacturer to develop test set up which satisfies the standard requirements for product. Testing of equipments confirms the quality of materials being used, performance of product, & builds confidence at all levels. Testing should also to be done as per points given below:-

  • Declared parameters of velocity ratio, effort etc.
  • As per code or standard lay down. i.e. IS 3832 for CPB,IS 3938 for EHB,IS-3177& IS 807 for cranes.
  • Manually operated hoist shall be tested for 1.5 times of SWL(i.e. Proof load testing)
  • Electric wire rope hoist shall be tested for 1.25 times of SWL(i.e. Proof load testing )
  • Crane shall be tested for 1.25 times of SWL(i.e. Proof load testing )
  • Tool and tackle shall be tested for proof load of 2 times of SWL.
  • Any type test requirements followed.
  • Vigorous situation tests.(Automobile)
  • Cranes are verified for deflection test.
  • Speed requirements shall be verified in idle condition.
  • Electric performance including brake and limit switch function to be verified.
  • After testing it is advisable that all parts to be visually checked for any wear and tear, condition of wire rope or chain etc.

Now we shall explain in brief safety and inspection checks to be followed for Material Handling Equipments;
Material handling equipments are mainly divided in three major categories
1. Manual material handling
2. Lifting Tackles
3. Mechanical Handling.


We shall now talk on each topic one by one.
1) MANUAL MATERIAL HANDLING

  • Inspect the object for sharp edges, protruding corners, nails etc. before touching.
  • While manually lifting the material (Load) keep legs apart, bend knees; keep back straight to avoid sprains.
  • Keep load close to the body.
  • While moving with load/material makes sure your vision is not obstructed.
  • Do not drop drums, gas cylinders, barrels etc. on the road and roll them.
  • Use trolley or cart for transporting drums, Gas cylinders, barrels and carboys.
  • Drum cylinders, containing flammable
  • liquids should be kept away from sparks, flames, heat etc.
  • No material shall be stacked against walls or partitions to a height which can endanger the stability of wall.
  • The materials should be stacked safely and stack height should not exceed more than 5 Ft. above the ground.
  • Dumping, pilling or stacking of material below overhead electric lines should be totally avoided.
  • No material should be piled / dumped or stacked at random but only in areas specified for same.
  • Roads, passage ways should not be blocked by dumping, piling or stacking of materials.

2) LIFTING TACKLES

  • Do not exceed safe working load at any point of time.
  • Avoid crossing, twisting, knotting of a wire rope/chain sling.
  • Lift load smoothly, avoid jerks, impact and swings.

3) MECHANICAL HANDLING

General:

  • Check brakes, lifting mechanism, limit switches, controls, guards, wire rope, hook, blocks etc. of EHB, EOT cranes.
  • Check brakes, lifting mechanism controls, guards, tyres etc. of forklifts.
  • Never drive crane or a vehicle with wet or greasy hands.
  • Always drive vehicle at safe speed, slow down when taking turns, and blow horn at corners.
  • When driving without load keep forks minimum 15 cm. above ground.
  • Avoid sudden starts and stops.
  • Avoid carrying oil drums, gas cylinders on forklift boom.
  • Do not cross over conveyors and roller table.

We shall examine the main mechanical handling equipments like,
1. Hand operated chain pulley block
2. Electric Hoist Block
3. Crane

CARE & SAFE USE AND INSPECTION CHECKS:

1) HAND OPERATED CHAIN PULLEY BLOCK:

  • Never lift a load in excess of safe working load marked on the block.
  • Twisting of load chain should be avoided in single fall or multiple fall.
  • Load to be applied centrally.
  • No direct binding of load with load chain, i.e. never use load chain as a sling.
  • No extreme slant slinging.
  • No over lifting, No over lowering, No rough handling.
  • Don't forget to oil the load chain after use, do not use grease for lubricating load chain.
  • If Load chain jumps, does not work smoothly or marks in use, it is probably out of pitch & should be replaced.
  • Do not allow dirt and hard grease to gather in pockets of the load or hand chain.
  • Do not store or leave the pulley blocks lying on the ground where they can collect dirt.
  • Care shall be taken when replacing the chains that same Grade and size of chain is fitted; Grade of chain is marked on pulley blocks by manufacturer.
  • Gears should be periodically greased. (HPC lithon-2 is recommended)
  • Never weld the load chain.
  • Hook should be used with safety latch.
  • Hook should be periodically examined for opening, i.e. for elongation.
  • Never lift load from hook corner.
  • Examine the hook for swivel movement, that is top hook under no load and bottom hook with load should be possible to rotate.
  • Brake system is through Ratchet and Pawl mechanism, hence never remove pawl.
  • Friction washers should not be lubricated. They are made of brake lining material.
  • Operator should always wear helmet during operation and no person should stand under lifted load.
  • Operator should warn persons around to avoid any accidents.
  • Care should taken that lifted load should not swing during operation.
  • Handling to be done carefully while block is operated above furnaces or on any heating equipment..
  • It is always recommended to use Pulley Block as per class Designed.
  • Pulley Block should be examined, inspected & tested by an impartial & competent authority once in a year for its wear and safe working as certified in Factories Act 1948.

Routine examination
The chain pulley block should be regularly inspected for damage and wear and to ensure that it is operating smoothly. Where the hoist is used infrequently, a visual check should be made of the chain pulley block each time it is used.

The following is a guide to routine checks, which should be carried out, on a chain pulley block, which is used in normal operating conditions. Where a chain pulley block is used or stored outdoors or in corrosive or abrasive conditions, inspection and lubrication must be attended to more frequently.

 

External Inspection (Monthly checks)
Component / Function
Type of check
Inspection / Upkeep
Hook Inspect visually 1. There should be no deformation of the hook.
2. There should be no cracks, or serious damage.
3. Hook should hang square to lifting unit or top
yoke (top hook) or to bottom block side plates.

Rivets, Bolts & Nuts
Inspect visually All fasteners should be tight.
Chain Inspect visually Should be properly lubricated (Use "Cylesso
TK-140" oil) and free from rust and dust.
Slack end pin &Chain anchor pin Inspect visually Should not be bent.
Chain wheels Inspect visually Chain pockets should not be deformed / worn out. Should rotate freely.
Load Chain Inspect visually Should rotate freely and keep chain in the pockets
Guide Roller   of the chain wheel.

Stripper / Hand chain Guard
Inspect visually There should not be any damage and wear.
Lifting and Lowering Lift & lowe ra light load Hoist should operate smoothly and easily.
Pawl should click during lifting.
Braking Lift & lower Safe Working Load Lifting and lowering operations should be smooth without any of the following defects.
1. Load falls, if hand chain is released.
2. Load falls while lowering.
3. Load slips.


Internal Construction (Yearly checks)

A competent person, as per statutory regulations and to ensure the efficient and safe use of the chain pulley block should carry the routine inspection and tests given above, together with the following inspections every year.

Internal Construction (Yearly checks)
Component / Function
Type of check
Inspection / Upkeep
Ratchet Wheel & Pawl Inspect visually before dismantling brake (see below)
Wear on the ratchet wheel profile and pawl should not be excessive - pawl must engage fully in the ratchet teeth. The pawl should not be rusted. Check that the pawl stud is secure and
that the circlip / split pin is retaining the pawl.
Load Chain Wheels & Hand Chain Wheel Inspect visually
Clean out chain wheels pockets and check that these are not deformed.
Spur Wheels and Chain Wheels Inspect visually
Clean of all lubricant and check that gear teeth are not chipped, damaged or worn. Re-lubricate.
Chain Guide Rollers Inspect visually
Should not be damaged, worn or deformed and must rotate freely.
Stripper Inspect visually
Tip of stripper should not be seriously flattened or damaged. (If in doubt, consult a competent person or fit new items).
Brake
Examine the screw sleeve, split bush, friction washers, ratchet ring and hand chain wheel, pawl, pawl spring and pawl stud. All items must be in good condition. The faces of the screw sleeve, ratchet wheel and hand chain wheel must not be worn or scored. The bores of the screw sleeve and ratchet wheel should not be worn or scored.The friction washers should be measured with a vernier caliper. Minimum permissible thickness is 1.5 mm. Friction washers
must not be split or cracked.

 

TROUBLE SHOOTING CHART
Sr. No.
Trouble
Cause
Cure

1.

Load Slippage

a. Friction washer(s) may
be worn out.
a. Replace friction washers.
b. Friction washer(s) oily. b. Clean friction washer with sandpaper.
c. Screw sleeve & hand chain wheel is jammed. c. Clean screw sleeve & hand chain wheel square threads for burr / rust formation and re-assemble.
d. Check washer is not working. d. Check serration, if required, replace check washer. Adjust
Nyloc nut.
e. Ratchet wheel & pawl arrangement is not working. e. Check spring, if found defective, replace it. Check ratchet wheel & pawl, if worn out, replace them.Ratchet pawl stuck. Check & clean pawl stud.
2. Block not hoisting or lowering loads. a. Check for load chain twist.

a. Remove load chain twist.
b. Hand chain or load chain may be stuck due to foreign particles. b. Clean chain wheels & replace chain.
3. Block making noise. a. Split bush may be worn out.
a. Replace it.
b. Load chain stripper damaged. b. Replace it.
c. Load chain wheel pockets may be worn out.
c. Replace it.
d. Guide roller damaged. d. Replace it.
e. Load chain is jumping from wheel pockets. e. Check load chain dimensions, refer table & replace load chain.
f. Hand chain is slipping /jumping from wheel pockets f. Check hand chain dimensions, refer table & replace load chain.
4. Load chain failure a. Hoist is overloaded. a. Check load to be lifted & capacity.
b. Load chain may be worn out. b. Replace load chain.
c. Load chain may be twist. c. Remove load chain twist.

2) ELECTRIC WIRE ROPE HOIST

  • Never lift a load in excess of the safe working load marked on Hoist.
  • Always lift load vertically.
  • Never lift with the point of hook.
  • Never run the wire rope out too far.
  • Apply grease to the wire rope periodically.
  • Before use of hoist, examine the wire rope to ensure that there is no twist.
  • Do not lubricate any point of contactors.
  • Inspect the wire rope for wear and tear regularly.
  • Under no circumstances should the hoist be operated when Limit Switch is not operating properly.
  • Ensure that the rope drum is perfectly horizontal when Hoist is used as a fixed suspension unit.
  • Examine the supply provided and connections are made accordingly.
  • Examine brake operation periodically and set the brake adjustment.
  • Periodically examine the bolts and nuts. If required tighten them.
  • Load should not be allowed to swing during operation.
  • Operator should use helmet.
  • Never open any electrical contact when supply is ON.
  • Hoist should be examined, inspected & tested by an impartial & competent authority once in a year for its wear and safe working as certified as Factories Act 1948.
  • Always use lubricant for gears as recommended by Hoist Manufacturer.
  • Periodically examine that no foreign particles accumulate on Beam on which Trolley is moving.
  • Care should taken that Electric hoist block fitted on Beam should be properly ground if it welded.
  • Do not leave load suspended in the air for long time.
  • It is always recommended to use Hoist as per class Designed.
  • Electrical parts shall be protected, if application is out door.

AFTER A PROLONGED STOP OR WHEN MAKING A ROUTINE EXAMINATION

1. CHECK operation of brakes.
2. CHECK operation of limit switches.
3. CHECK for damaged hooks, ropes or cables.
4. KEEP rope clean and well lubricated.
5. CHECK the wire rope for improper seating, twisting, kinking, wear or other defects before operating the hoist.
6. CHECK that suspending cables of the Control Box are not broken or loosen. If the cable is damaged, change it.

WHEN IN USE

1 HOLD the load in a balanced way, securing it by using appropriate equipment (sling…).
2 MAKE SURE the load clears vicinity, stock piles, machinery, or other obstructions when raising, lowering or moving the load.
3 CENTER hoist directly above the load before operating, never pull from the side.
4 MAKE SURE that the load is high enough to see and avoid any obstacle lying on the ground.
5 AVOID swinging the load or hook block when traveling.
6 MAKE SURE that the load is correctly held in the hook.
7 CHECK that the rope reeving is correctly tight (slackness not desirable).
8 KNOW AND USE the hand signals for hoisting and traveling.

3) CRANE
Crane is general word .Various types of cranes are:-

  • Hand operated traveling crane (HOT)
  • Electric overhead Traveling crane (EOT)
    • Sub divided as
    • Gantry crane
    • Cantilever crane
    • Jib crane
  • Wall/Pillar mounted jib crane
  • Portal crane
  • Mobile crane
  • Locomotive crane
  • Never lift a load in excess of the safe working load marked on crane
  • Always lift load vertically.
  • Never lift with the point of hook.
  • Never run the wire rope out too far.
  • Apply grease to the wire rope periodically.
  • Before use of crane, examine the wire rope to ensure that there is no twist.
  • Do not lubricate any point of contactors.
  • Inspect the wire rope for wear and tear regularly.
  • Under no circumstances should the crane be operated when Limit Switch is not operating properly.
  • Examine the supply provided and that connections are made properly.
  • Examine brake operation periodically and set the brake adjustment.
  • Periodically examine the bolts and nuts, if required tighten it.
  • Load should not be swing during operation.
  • Operator/helpers should use helmets.
  • Never open any electrical contact when supply is ON.
  • Crane should be examined, inspected & tested by an impartial & competent authority once in a year for its wear and safe working as certified as Factories Act 1948.
  • Always use lubricant as recommended by crane Manufacture.
  • Periodically examine that no foreign particles are accumulated on crane movement path, i.e. on beam.
  • Do not leave load suspended in the air for long time.
  • It is always recommended to use crane as per class designed.
  • Lock the movement of crane when it is not in use.
  • Switch off the power supply when crane is idle.
  • Periodically verify the supply wire conditions.
______________________________________________________________________________________________________________
 Bio-Data
Shri J.B. Bhatt is a Mechanical Engineer having PG Diploma in Business Administration and Chartered Engineer.
He has worked as Production Engineer with M/s Elecon Engineering Company, VV Nagar from 1979 to 1994. There after he also worked at Kalama Pumps for a year. Since 1995 he is working as a Manager (Q.A.) with M/s Brady & Morris Engg. Co. Ltd., Ahmedabad.