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ANNEXURE

1. INTRODUCTION-

a) Definition

b) Requirement

c) Types

d) Components

e) Lifting Equipment

2. THEORY

3. TACKLES AT JCB

4. TACKLE SAFETY ASSESSMENT

5. LOAD CALCULATION- Basis

6. SCOPE OF IMPROVEMENT

7. BEFORE n AFTER

8. REFERENCES

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INTRODUCTION

a) DEFINITION: A mechanism consisting of ropes, chains, belts, pulley blocks, hooks, or other

connecting links for lifting heavy objects.

b) REQUIREMENT: The requirement of tackles is as follows:

1. Tackles tackle the problem of lifting heavy objects in an industry.

2. Tackles play an important role in material handling by making movement of material easy,

safe and fast.

3. They help making loading and unloading process much safer and easier.

c) TYPES: Tackles used in the industry are designed according to the load they have to lift and

also the shape and size of the object in order to lift the load properly and ensure safety of the

operator.

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Following are the various types:

1. Single Leg

2. Double leg

3. Triple and Quad leg

Apart from this, Tackles can be of various shapes and sizes, containing frames, plate hangers

as per requirement.

d) COMPONENTS: Tackles are build up using following components:

1. Chains

2. Belts

3. Hammer locks

4. D-shackles

5. Oblong rings

6. Lifting beams

7. Hooks

8. Safety ropes

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1 2 3 4

5 8

1

7

1

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e) LIFTING EQUIPMENT: Lifting equipment comprises of mainly three parts:

1. Lifting Machine

2. Lifting Tackle

3. Fabricated Equipment

The following figure depicts it correctly.

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THEORY

As described earlier, Tackles may be made up of various components. Tackles that are made up of

chains are also termed as chain slings.

CHAIN SLINGS:

STRUCTURE

Chain slings are lifting accessories comprised of a chain and connected lifting gear. They can be single

or multi-legged. Each sling must be fitted with a marking plate displaying the working load limits for

different loading situations. A visual inspection must be carried out before using the sling to verify that

the sling and sling fittings are in due order. Chain slings can typically be used at maximum load in a

temperature range of -40C to +200C. The manufacturers instructions must be observed for operation

in temperatures outside this range. Chain slings should have a designated storage place (e.g. rack)

where they are not susceptible to damage and can be easily obtained. Load tables and lifting

instructions should also be located at the storage place.

CHAIN

The chain consists of steel links. Lifting slings must be made of short link chain only. The required

properties of the chain are stipulated in the relevant standards for sling chains. Documents specifying

the technical properties of the chain must be readily available during chain sling assembly. Any fittings

attached to the sling must be at least as strong as the chain itself.

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MASTER LINK

One or more sling legs are connected to the master link via a suitable connection method. For each

lifting operation, check that the master link is compatible with the lifting appliances hook (i.e. big

enough).

HAMMER-LOCK

Hammer locks are used in chain sling assemblies to connect its various components. The hitch

configuration system ensures that components of the wrong size cannot be connected to each other.

Sling importers each supply connectors that are compatible with their own chains.

HOOKS

Sling hooks must consist of self-locking hooks or sling hooks equipped with a sufficiently strong

safety latch. Open hooks may be used only in special cases where it is ensured that no hazard to

personnel, nearby objects or materials will be created during the lifting operation. The load must

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always be set squarely within the hook bowl. The hooks safety latch must be of sufficient strength and

laterally supported to be able to fully withstand the loading and operating stresses.

INSPECTION AND REJECTION CRITERIA FOR CHAIN SLINGS

Chain slings must be measured and their entire length inspected during periodic inspections. The

lengths of the different legs of multi-legged slings must be compared. Special consideration must be

paid to possible stretching, wear, cracking, deformation and external damage of the different sling

parts. Detailed link-by-link inspection is the only means of detecting these damages. The cause of the

perceived damage must always be clarified and steps taken to prevent the fault from recurring.

The inspection must be made in accordance with the manufacturers instructions. Chain sling

inspections are usually based on the following rejection criteria:

A chain sling must be taken out of use if:

1. The slings working load limit for different load situations is not clearly marked on the sling.

2. The slings master link, hooks or other components contain bends, fractures, warping, other

deformation or the hook mouth has opened more than 10%.

3. Any chain link has worn more than 10%. The chain links are measured in two planes. Their

average dimensions must be at least 90% of their original dimensions. In this way, the level of

wear until the next inspection can be predicted.

4. Slashing, notching, pitting or corrosion caused by external factors is more than 10% of the

material thickness, or the degree of deformation is visually perceptible.

5. Colour change caused by heat damage is perceived.

6. Damage caused by weld splash is perceived.

7. The mechanical connector is worn, bent, warped or cannot turn freely.

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SYNTHETIC ROUND SLINGS AND LIFTING BELTS:

The use of round slings and lifting belts made from synthetic fibre has become increasingly

widespread. They are easy to use due to their lightness and their surface quality is well suited to the

lifting of delicate materials. On the other hand, they are more susceptible to damage than other slings.

There are fundamental differences between round slings and lifting belts. Confusing the two can, in

certain situations, be hazardous. The most essential difference is in their inner structure. The load-

bearing yarns of belts are woven into a band, whereas round slings consist of endless loops of load-

bearing yarn enclosed within a tubular cover.

Lifting Belts

Round Slings

MATERIAL

Lifting belts and round slings are made from synthetic fibre yarns made of either polyester, polyamide

or polypropylene. The most common yarn material used in Finland is polyester. The sling material

must also be UV radiation protected. The material properties of synthetic fibre round slings and belts

are rarely considered at the procurement stage. The user must, nevertheless, at least understand the

effect of the lifting site conditions on the lifting accessory. Is the site exposed to high temperatures?

How might any chemicals used affect the sling/belt? Is there UV exposure? Do the lifted loads have

sharp edges?

The sling/belt material is indicated by the sling label colour-coding:

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WORKING LOAD LIMIT

The sling angle factors and working load limits for different sling angles are shown in the instruction

tables provided by the manufacturer or importer. These tables should be kept at the site of use of the

lifting slings.

Fig: Sling angle factors for round slings

Fig: Sling angle factors for Lifting belts

SHARP EDGES AND EDGE PROTECTION

Contact of the lifting sling with sharp edges during the lifting operation dramatically reduces the

slings strength. Burs, load imbalance, stop/start jolting during lifting or worn slings further increase

the damaging effect of sharp edges. A sharp edge with a corner radius of 1 - 7 mm reduces the load-

bearing capacity of lifting belts and round slings by 50%. With lifting belts, a 13 mm corner radius is

required to maintain a load-bearing capacity close to that of straight lifting. According to experience,

edge protection must be used whenever the corner radius is below 7 mm. A wide range of edge

protection types and materials are available for specific applications.

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OPERATING INSTRUCTIONS FOR SYNTHETIC SLINGS

1. Before lifting, perform a visual inspection of the full length of the sling and check that the

working load limit is clearly marked.

2. Only use slings that are in full working order.

3. Take into account the effect of the lifting method on the load. Do not exceed the working

load limit.

4. Be wary of sharp edges and coarse surfaces. Use edge protection.

5. Ensure the load remains balanced for the entire lifting and transfer operation.

6. The lifting hook must be big enough with respect to the belt width and the hook edges

7. must be rounded off. Ensure that the sling is set squarely in the bowl of the hook and is

evenly loaded.

8. The leg angle of hooked eye belts must not exceed 20 degrees.

9. Never tie knots in the sling. Knots weaken the strength of the sling, endanger the lifting

operation and may ruin the sling.

10. For load temperatures over 80C follow the manufacturers instructions.

11. Chemicals and solvents can damage the sling.

12. Avoid sharp stops/starts by slowly accelerating and decelerating during the lift. Avoid any

kind of jolting during the lifting operation.

13. Lower the load onto its landing platform so that the sling can be removed without

damaging it. Do not forcefully remove the sling.

14. If multiple slings must be used simultaneously due to the length of the load, prevent

sliding of the lifting accessory in the lifting hook and on the load.

INSPECTION AND CONDITION MONITORING OF LIFTING BELTS AND

ROUND SLINGS

Lifting belts and round slings are more susceptible than other lifting accessories to damage and must

therefore always be condition checked before each use. Lifting belts must be visually inspected along

their entire length on both sides for surface damage, longitudinal or transverse band cutting, edge

cutting, wear damage and stitch or

eye damage. The condition of round slings must be estimated according to the condition of their outer

coating, as the load-bearing yarns are sealed within the coating. In addition to visual inspection, the

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condition of the load-bearing yarns must be felt to verify that they are free of any hardening and that

the core is regular in shape. Some hardened areas felt inside the sling may be due to tape bindings used

in round sling manufacture. Users of lifting belts and round slings must be given sufficient guidance in

their condition assessment. In addition, a competent expert must check the condition of the slings at

least once a year and verify their suitability for use with respect to the existing lifting conditions. One-

time-use slings are often supplied with new machinery for purposes of moving it and lifting it into

position. These throwaway slings must be disposed of immediately after use.

A lifting belt must be taken out of use if:

1. The working load limit marking is not clearly visible.

2. The belt has been overloaded.

3. The belt contains a knot.

4. The belt has extensive abrasion damage or is generally worn and dirty.

5. More than 10% of the warp yarns (load bearing yarns) are severed or yarns are damaged on

the belt edge.

6. The weft yarns are broken along a more than 5 cm length.

7. Slash damage or abrasion damage of the surface exceeds 10% of the transverse direction.

8. Damage has been caused by chemicals, heat or moisture.

9. Yarn breaks exist at the belt terminations or the terminations are considerably worn.

10. The joint stitching has come unstitched.

A round sling must be taken out of use if:

1. The working load limit marking is not clearly visible.

2. The sling has been overloaded.

3. The inside of the sling is damaged.

4. The sling contains a knot.

5. The outer coating is broken to the extent that the inside is visible.

6. The outer coating shows signs that a welding spark, lathe chip or equivalent has damaged

the load-bearing yarns.

7. The sling cover has extensive abrasion damage or is generally worn and dirty.

8. Damage to the load-bearing yarn has been caused by chemicals, heat or moisture.

MAINTENANCE AND REPAIR

Do not attempt to carry out repairs yourself. Dirtied lifting belts and round slings can be washed in

tepid water using a neutral detergent. Lifting belts and round slings that have been wetted during

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washing or otherwise must be left to dry in either a hanging or laying position. They must not be spin-

dried. Store synthetic slings in a well ventilated space on a rack designed for the purpose so that they

are not susceptible to chemicals, solvents, ultraviolet radiation, temperatures over 70C or varying

climatic conditions. Remember to only use round slings and lifting belts that fulfil strict quality

requirements. Observe the instructions provided by the manufacturer and refer any problems

encountered to the manufacturer.

LIFTING CLAMPS:

Clamps are used for lifting plates and sheets, profiled products and pipes. The holding force is

typically based on the grip between the clamps toothed eccentric cam and the surface of the lifted

item.

Lifting clamps must show the following markings:

1. working load limit

2. minimum and maximum thickness or width of lifted items

3. production/serial number

4. name of manufacturer/supplier

5. CE marking

In addition, the clamp must be marked with any possible use restrictions. The operating instructions,

maintenance and inspection instructions and Declaration of Conformity included with each clamp

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delivery must be observed. Clamps that are not equipped with safety locking to safeguard against

accidental loosening of the load must not be used for vertical lifting of plates or sheets.

WHEN USING CLAMPS

1. Check that the clamp is in order and suitable for use and that the surface hardness of the

lifted item does not exceed the maximum surface hardness permitted for the clamp.

2. The clamp must be compatible with the lifting appliances hook and, if necessary, a chain

sling with a sufficiently large ring must be used.

3. Do not exceed the working load limit.

4. Check that the contact surface is free of scale, paint, dirt, ice, grease or other substances

that may weaken the holding capacity.

5. Always observe the designated loading direction of the clamp. The clamp must be

positioned to follow the lifting direction of the sling.

6. Pendular motion of the fastened item must be prevented, as this can damage the clamps

cam teeth. When lifting long plates or sheets, two or more clamps and lifting booms

should be used. Lift only one plate or sheet at a time when vertical lifting with a

plate/sheet lifter.

7. At least two pairs of horizontal clamps should be normally used. Do not exceed the

maximum sling angle specified by the clamp manufacturer.

8. When turning or moving, always keep the end of the plate/sheet or lifted load towards you.

Lifting above personnel is strictly forbidden.

9. Wear of the contact surfaces of the lifting clamps cam segment and counter jaw must be

monitored and inspection intervals shortened as necessary.

10. If the clamp has undergone repair, its operation must be checked by means of a test lift.

SPECIAL OPERATING INSTRUCTIONS FOR SCREW CLAMPS

1. The clamp must be compatible with the lifting task. For example, clamps that base their

holding capacity solely on the manual tightening force of the screw must not be used for

vertical lifting of plates or sheets.

2. The holding force is based on the friction force between the cam segments and the surface

of the lifted item, so the clamps must have toothed, hardened cams.

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3. The optimum holding force is attained if the cam section includes a swivel joint that

wedges the jaw more tightly closed as lifting commences.

LIFTING MAGNETS:

There are two basic types of lifting magnet on the market: permanent magnets and electromagnets. In

addition, electrically connected permanent magnets offer a third, intermediate alternative.

Electromagnets include mains current and standby battery operated accumulator models. The

advantage of permanent magnets is their minimal maintenance and simple structure.

The lifting capacity of lifting magnets is derived from the magnetic field that forms between the

magnet and the lifted item. Factors affecting the size of this magnetic field and, thus, the load holding

power include:

1. Lifting capacity reduces with reduced contact surface area of the magnet shoes. The magnet

shoes must be clean and smooth. They must not be machined. Any irregularities must be

carefully ground smooth.

2. Thin-walled items do not create an effective magnetic field.

3. The surface quality of the lifted item.

4. Air gaps strongly reduce the lifting capacity.

5. Air gaps result from surface unevenness, burs, scale, grease, paint etc.

6. The shape of the lifted item. When lifting round and curved items, rounded pole shoes must be

used to achieve a sufficient contact surface. In this case the lifting capacity is always lower

than when lifting flat items.

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7. The overall dimensions of the lifted item. Long items tend to bend, creating air gaps at the

edges of the magnet.

8. Position of the magnet. Standard magnets can be lifted only in the horizontal position.

9. Variable magnetism of lifted items. Some materials do not magnetize at all. The optimum

holding capacity is attained with unalloyed low-carbon steel.

10. The weight of the lifted load must be proportioned according to the magnet manufacturers

instructions.

11. Magnets must not be used in high temperatures. The manufacturers instructions must be

observed in this respect.

12. The holding capacity of the magnets must be checked at regular intervals by test lifting using

the same loads typically lifted by the lifting magnets.

LIFTING BEAMS:

A wide range of different loading capacities, shapes and lengths of lifting beam are available. Lifting

beam components and other equipment should also be optimally designed to suit the beams specific

function. Lifting beams or spreader beams can effectively reduce the load stresses on the sling or

on the load itself. Lifting beams are the ideal lifting accessories for workspaces with limited headroom

where the use of lengthy top rigging is not possible. The lifting beam designer and manufacturer must

have the necessary expertise in lifting beam design and production, including sufficient knowledge of

material strengths and structural requirements.

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Lifting beams must have the following markings:

working load limits for different loading situations

dead weight of the beam, to enable determination of the lifting appliances payload capacity

production/serial number, name of manufacturer and CE marking

The following must be observed upon delivery of the lifting beam:

operating instructions, including possible restrictions on use

maintenance and inspection instructions and assembly drawing

Declaration of Conformity

SHACKLES:

Shackles used for lifting must be designed for the lifting task in question. Shackles are loose lifting

gear. As such, they must either be marked with their working load limit or their rated capacity and

possible restrictions on use must be specified in the operating instructions provided upon delivery.

Always fully tighten the shackle pin before lifting. Fixed joints and attachments that can- not be

continuously monitored must be fitted with e.g. a cotter to prevent the pin from opening. Loading of

the shackles should be perpendicular to the pin.

INSPECTION

Visually check that the pin thread is intact and that the shackle is free of fracture or deformation.

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TACKLES AT JCB - BACKHOE LOADER

Tackles are used for lifting various components of different weights, shapes and sizes. Assessment of

tackles in following departments has been done:

1. Fabrication Business Unit (FBU)

2. Assembly Business Unit (ABU)

3. Paint Business Unit (PBU)

4. Logistics Distribution Centre (LDC)

There are more than 500 tackles in the Backhoe loader division. Tackles of various shapes and sizes

can be easily found anywhere in the plant. They play an important role at each and every stage in the

manufacturing process.

- Tackles are used in fabrication unit (FBU) for following purposes:

a. Loading child parts onto the fixtures

b. Unloading tacked components

c. Loading and unloading the tacked components on the welding manipulators

d. Loading and unloading at the robot cells

Fig: Loader arm Tackle Fig: Dipper being loaded on Robot cell

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- In the Paint shop (PBU), Tackles are required for:

a. Loading components onto the trolleys

b. Carrying the trolleys on the overhead conveyor

c. Unloading Painted components from trolleys

- At the assembly line (ABU), tackles perform following tasks:

a. Loading various components like Tires, Radiator, Battery, Cabin from the materials conveyor

Fig: Mainframe being loaded on manipulator Fig: Boom being unloaded from drill m/c

Fig: Boom Loading tackle Fig: Overhead conveyor tackle

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b. Carrying Loader arm, Boom-Dipper Trolley, Mainframe, Skid assembly using overhead

conveyor

c. Loading and Unloading from the assembly conveyor

- At the Logistics Distribution Centre (LDC), tackles are used for unloading material racks and

trolleys from the trucks. Also tackles are used for loading Boom-Dipper sets, loader arms and

Mainframes, for export, onto the trucks.

At the JIT store, Tackles are again employed for loading loader arms, KPC, Dipper, Boom etc.

Fig: Boom-Dipper Tackle Fig: Engine Tackle

Fig: Loader Arm Overhead conveyor tackle Fig: Tire Tackles Fig: Loader Arm Overhead conveyor

tackle

Fig: Tire Tackles

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Fig: Mainframe export tackle Fig: Loader Arm tackle at JIT area

Fig: Gear Box housing Tackle at LDC Fig: WBC Tackle at LDC

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TACKLE SAFETY ASSESSMENT

Section 19 of the Safety, Health and Welfare at Work Act, 2005 requires that employers and those who

control workplaces to any extent must:

identify the hazards in the workplaces under their control

Assess the risks presented by these hazards In this context a hazard is something with the

potential to cause harm (for example, chemical substances, machinery or methods of work),

while measuring the risk.

The Management of Health & Safety at Work Regulations 1999 requires a competent person to carry

out a suitable and sufficient risk assessment, in order to identify the nature and level of risks associated

with a lifting operation. Factors requiring consideration include:

The type of load being lifted, its weight, shape and what it consists of;

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The risk of a load falling or striking a person or other object and the subsequent consequences;

The risk of the lifting equipment failing or falling over while in use and subsequent

consequences.

Following measuring instruments have been used for safety assessment of tackles in order to find out

their load capacity.

1. Digital Vernier Caliper

The digital vernier caliper has been used to measure the chain thickness in order to make an estimate

of its load bearing capacity. Moreover the internal diameters of bushes, hook holes have been

measured using this. Outer diameter of Master links, hammer locks, D shackles has also been checked

with standards with the help of vernier caliper.

The advantage of using a digital vernier caliper is its least count, i.e., 0.01 mm as compared to 0.02

mm in case of analog one. It is very easy to use, accurate and time saving.

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2. Angle Finder

The angle at which the chains and belts are inclined with the horizontal axis while lifting or carrying a

load, plays an important role in its load capacity calculations. So, in order to find the inclination

angles, Angle finder is used.

3. Measuring tape

To measure lengths of chains, belts and other linear dimensions, Measuring Tape has been used.

WORKING STANDARDS FOR DIFFERENT LIFTING ACCESSORIES:

Safety Assessment can only be done properly if the working standards are known. Following tables

depict clearly the working standards of various lifting accessories being used to make tackles at JCB.

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1. CHAINS:

Single leg Chain

Double leg Chain

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Triple and Quadruple Chain

2. HAMMER LOCK:

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3. D SHACKLES:

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LOAD CALCULATIONS- Basis

The basis for load calculation of Tackles is based on Lamis Theorem.

LAMIS THEOREM:

In statics, Lami's theorem is an equation relating the magnitudes of three

coplanar, concurrent and non-collinear forces, which keeps an object in static equilibrium, with the

angles directly opposite to the corresponding forces. According to the theorem,

where A, B and C are the magnitudes of three coplanar, concurrent and non-collinear forces, which

keep the object in static equilibrium, and

, and are the angles directly opposite to the forces A, B and C respectively.

Lami's theorem is applied in static analysis of mechanical and structural systems.

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SCOPE OF IMPROVEMENT

There is a huge scope of improvement as far as tackles are concerned. According to the present

scenario, tackles, specifically in the Fabrication Unit are not organized properly. There are chances of

the tackles being misplaced.

Following are the points of improvement:

COLOR CODING OF TACKLES: Color coding is a simple and very effective solution for

preventing the tackles from being misplaced. For e.g. In Fabrication Unit, there may be a case

when a tackle of Boom Tacking may get swapped by a tackle of P-458 Boom Tacking.

However the design is same and both look identical but this is not safe because the weights of

both components are not same.

Moreover, Color coding may help the zone incharges to keep a record of the tackles they have.

TACKLE STANDS: Tackle stands are completely missing in the Fabrication Unit. Tackles are

kept on the shop floor. So, in order to ensure safety and proper organization of tackles in the

unit, stands are a must.

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TAGGING: Tagging of each and every tackle is a must. The tag will contain the tackle

number and zone name on it. This will help in recognizing the tackles easily with different

zones.

NEWLY DESIGNED TACKLES AT ROBOT CELLS: To ensure safety of the operator while

loading and unloading the components at the robot cells, new tackles are to be designed. Also

tackles are to be designed in such a way that allow supply of air to the air gun once the

component is loaded onto the manipulator and it has to be clamped now.

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BEFORE n AFTER

DIPPER ROBOT CELL SAFETY CONCEPT

BEFORE AFTER

The tackle shown above does not

contain any attachment that may be

sensed by the photo sensor or

something like that.

Prior to introducing the new tackle, the

clamping and de-clamping was done

manually with a spanner.

The above tackle contains a plate

attached to it which is sensed by the

photo sensor on the robot cell when

the component is loaded onto the

manipulator.

When the sensor senses the tackle on

the manipulator, then it sends a signal

to PLC that switches on supply of air

to the air gun for clamping the

component onto the manipulator.

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DESIGN OF TACKLE:

Chain Thickness: 10mm

Chain Length: 680mm, 1230mm

Master Link: 3 Ton (1)

Hammer Lock: 3.15 Ton (1), 2 Ton (4)

J Hook: 2

Lifting Frame with sensing plate: 1

Sensing Plates

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REFERENCES

Tackle Manuals

Tackle list by Intenco Engineering certifications

http://tyosuojelujulkaisut.wshop.fi/documents/2007/09/TSO_12.pdf

http://www.vanbeest.com/getattachment/aa492c75-5752-4fe6-84fc-b506b6fe93ab/Chapter01-

Shackles.aspx

A textbook on Engineering Mechanics R.S. Khurmi, S Chand Publications

http://www.liftpro.com/SLINGS,%20CHAIN/chaincatalogread.pdf