Views: 1 Author: Site Editor Publish Time: 2022-10-12 Origin: Site
Instructions for care and use of POLYESTER SLINGS
1. Always work within the SWL of your slings. Increasing the angle between the sling legs reduces the lifting capacity. Always consult your Lifting Chart.
2. Never use damaged slings.
3. Do not, under any circumstances, tie knots in the sling – this will result in loss of strength and sling damage.
4. Never drag goods in the sling.
5. Always position the sling in such a way as to ensure easy removal after use.
6. Always use smooth, rounded hooks having an inside radius of not less than the sling width.
7. Avoid placing more than one sling on the same hook.
8. Keep slings away from acids and alkalis.
9. Never use unprotected slings around sharp edges or corners. Where lifts involve loads with sharp edges, use protective sleeves to protect your sling from abrasion or cutting.
10. When lifting heavy cargo using more than one sling, remember that the total weight of the load may not be evenly distributed.
11. Do make sure that your slings are made to ENSTD 1492. Look for the label indicating this, the maker’s name and the safe working load of the sling. Also certification should be provided by supplier
Use in adverse conditions
Adverse conditions or hazardous applications: The materials from which round slings are manufactured have selective resistance to chemicals.
The resistance of synthetic fibres to chemicals is summarized below:
· Polyester (PES) is resistant to most mineral acids but is damaged by alkalis;
· Polyamides (PA) are virtually immune to the effect of alkalis; however, they are attacked by mineral acids;
· Polypropylene (PP) is little affected by acids or alkalis and is suitable for applications where the highest resistance to chemicals other than solvents is required.
Solutions of acids or alkalis which are harmless can become sufficiently concentrated by evaporation and cause damage. Contaminated slings should be taken out of service at once, soaked in cold water, dried naturally and referred to a competent person for examination.
Slings with grade 8 fittings and multi-leg slings with grade 8 master links should not be used in acidic conditions. Contact with acids or acidic fumes causes hydrogen embrittlement to grade 8 materials. Temperature affects:
· Polyester and polyamide: -40 °C to 100 °C,
· Polypropylene: -40 °C to 80 °C.
At low temperatures ice formation will take place if moisture is present. This may act as a cutting agent and an abrasive causing internal damage to the sling. Further, ice will lessen the flexibility of the sling, in extreme cases rendering it unserviceable for use.
Limited indirect ambient heating, within these ranges, is acceptable for drying.
Effects of ultra-violet radiation: The man-made fibres from which the round sling is produced are susceptible to degradation if exposed to ultra-violet radiation. Round slings should not be stored in direct sunlight or sources of ultraviolet radiation.
Before first use of the sling it should be ensured that:
· The sling corresponds precisely to that specified on the order;
· The manufacturer’s certificate on hand;
· The identification and WLL marked on the sling correspond with the information on the certificate (where appropriate, the additional protection sleeve is moved so that the tag can be read) – as per the EN STD.
· The sling has been maintained.
· The sling is suitable for intended lifting.
Preparation: When selecting and specifying roundslings and webbing slings, consideration should be given to the required working load limit, taking into account the mode of use and the nature of the load to be lifted. The size, shape and weight of the load, together with the intended method of use, working environment and nature of the load, all affect the correct selection.
The selected sling should be both strong enough and of the correct length for the mode of use. If more than one sling is used to lift a load, these slings should be identical. The material from which the roundsling is made should not be affected adversely by the environment or the load.
Consideration should also be given to ancillary fittings and lifting appliance which should be compatible with the sling(s). Design of the slings end should also considered, i.e. if end fittings or soft eyes are suitable.
When a sling with soft eye are used together with a hook/fittings the smallest length should not be below 3.5 times the hook’s/fitting’s
Maximum thickness and the angel that form in the eye shall never, in any case, exceed 20°.