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BEFORE EACH USE A sling is exposed to the possibility of damage every time it is used. Even when used well within its safe working load, there are a lot more opportunities for an error which might leave the sling less safe or even dangerous the next time it is used. This is because the sling may connect to the load by wrapping around or passing through it, and may be used at an angle or in choke. Therefore slings should always be checked every time before use. This does not have necessarily a time-consuming job. An experienced stinger should be able to cast their eye over a sling in seconds, and there is no need for records of such inspections to be kept. However, in case of doubt or damage there should be a procedure to withdraw the sling from service immediately, and have it inspected by a competent person. Make sure the load is free to move and is not bolted down; verify the sling working load limit is greater than the total weight to be lifted The position of the centre of gravity must ensure a safe lifting and avoid tilting, toppling or swinging. Make sure that: • for single leg slings the bearing point is placed vertically above the centre of gravity • for two legs slings the bearing points are placed on both sides symmetrically and over the centre of gravity • for three and four slings the bearing points are distributed in plan around the centre of gravity or over it
LOAD HANDLING To avoid dangerous swinging of the load the angles to the vertical should be greater than 15°. Simmetry If the load tilts, it should be lowered and the bearing points moved in a safer position. Alternatively legs should be shortened by using proper shortening devices. Load protection To avoid load damage is necessary to make sure that the horizontal reactions are well absorbed. The greater is the angle to the vertical the greater are the reactions on the load. Do not exceed 60°. Lifting Start lifting avoiding sudden accelerations. Lift the load with care until all the legs are taut. Keep far from chain legs and, in general, keep far from lifting area. At low temperatures all liftings should be performed at a slow rate; any shock should be avoided; don't change the speed Landing Make sure that landing area is free. Avoid sudden decelerations. Check the load is stable before releasing legs sling. Avoid trapping the sling beneath the load as this may damage it.
Edge load - protection of load and chain The maximum load capacity of chain slings is defined under the assumption that the individuai chain legs are pulled straight under load. In the case of edge loading, load protection should to be used to avoid damage.
MAINTENANCE A competent person must inspect the sling for obvious damage. If faults are found or if there is reason to doubt about the safe condition the sling must be removed immediately from service. Before starting the inspection ensure that the sling is in a reasonably clean condition and there is adequate lighting. Be methodical and try to follow a regular routine so that it becomes automatic. It is a good idea always to work from the top down.
Master link Look at the shape of the master link. Because this link has large internal dimensions to accommodate a crane hook, it tends to be the first component of a sling to collapse and elongate if the sling has been overloaded. Check also for: • twisting and distortion in other directions (fig.1) • elongation: must not exceed 5% of the original internal length (B-A)100/A (fig.2) • wear: must not exceed 10% of the original diameter (C-D)100/D (fig.3) • markings: missing or illegible marking make the master link unsafe if one of these event occurs replace the master link

Coupling links With the half link design, the two halves should articulate about the pin but corrosion can cause them to seize. If they were allowed to seize when flexed and then straightened under load, the pin or the forgings can fail. Check for any seizure, damage or substituted components. Check also for: • wear: must not exceed 10% of the original diameter (d2-d1)*100/d1 (fig.5/a) • elongation: must not exceed 5% of the original internal length (fig. 5/b) • markings: missing or illegible marking make the coupling link unsafe if one of these event occurs replace the coupling link with an identical one

Shortening devices One of the advantages of chain slings is the ease with which the leg length can be adjusted if the leg is fitted with a chain clutch. However, misuse can damage both clutch and chain. Some designs prevent the chain being inserted incorrectly but others do not. Incorrect use can distort the forging and cause localised damage to the chain. Irrespective of the design, back hooking into the chain loop above the clutch is a thoroughly bad practice, but nevertheless sometimes seen. It can cause damage. Check also the integrity of the connection between the clutch and the top link.
Chain Most likely defects arise from misuse. Norma! wear occurs at the interlink seats but slings which have been dragged along the ground can have significant wear on the outsides of the links. When overloaded, the chain elongates, resulting in a lack of articulation between the links and, in extreme cases, the chain becomes rigid. Check that it flexes freely. On a multi-leg sling, compare leg lengths. Local stretch in a section of leg can occur if the sling has been abused by the so-called practice of battening down a choke hitch. Look for bent or notched links which can arise from such abuse or from loading over corners without adequate packing. Check also for: • permanent twist which can occur if the leg was loaded when twisted • elongation: must not exceed 5% of the original internal length (B-A)100/A (fig.2) • wear: must not exceed 10% of the original diameter (C-D)100/D (fig.3) • markings: missing or illegible marking make the chain unsafe if one of these event occurs replace the chain
Lower terminal fittings These are usually some form of hook but can also be links. Hooks can be distorted at well below their safe working load if they are loaded on the tip instead of in the bowl. Reject any which show signs of twist or opening out. For hooks with a safety catch, an obvious indication of damage is the catch not fitting. Check also that the catch itself is not damaged or ineffective. Self locking hooks rely on a latch mechanism which can be affected by deposits such as cement. On some designs, wear of the latch will allow the hook to unlock if it is tapped sharply on the back. Hooks are connected to the chain by either a clevis and pin or a coupling component similar to that which connects the chain to the top link. Check that the correct pin is properly fitted and retained, is in good condition and that the coupling articulates. Check also for: • wear: must not exceed 10% of the original dimension (i.e. the eye of a hook) (d2-d1)*100/d1 (fig.5/a) • elongation: must not exceed 5% of the original length between bearing points • pin wear: must not exceed 10% of the original diameter • hooks opening must exceed 10% of the original dimension • markings: missing or illegible marking make the fitting unsafe if one of these event occurs replace the fitting with an identical one
	green zone: repair not required red zone: max wear 5% of original dimension orange zone: max wear 10% of original dimension
Identification Check that the sling identification and safe working load markings are present and legible. These are usually on a tag fixed to the top link or stamped directly into the top link. If the tag is not fitted or the markings are not legible withdraw the sling from service.
PERIODIC THOROUGH EXAMINATIONS As per EN818 we recommend subjecting the chain every year, or after any unusual event (overload – heat exposure - …) to a load test with 1.5 times the load capacity, followed by a visual inspection, or to another type of cracking test (Magnetic Particle Test). These test must be performed by an expert.
REPAIR TIL lifting accessories and chain slings should only be repaired by qualified personnel using genuine TIL parts. When the repair is carried out through the substitution of components that have already been tested (such as connecting link, etc) a proof test for the whole sling is not required.
Always follow these simple rules: • NEVER side load, tip load or back load a hook (fig.6) • NEVER repair, alter, rework or reshape a hook by welding, heating or bending • NEVER remove the safety latch • NEVER expose to acid or basic solutions or atmospheres • NEVER expose to temperatures over 400°C • NEVER apply any surface coatings to chain and fittings • NEVER hot dip galvanize or electrogalvanize chain and fittings • make sure the load is properly balanced • make sure the identification tag is properly fitted and the markings are legible • store in cleaned and dried condition and protected from corrosion, e.g. lightly lubricated.

fig.6

the picture doesn't show all the possible situation of danger - in case of doubt please get in touch with the technical dept

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