A round sling is manufactured by winding continuous polyester yarn into a closed loop, which is then encased in a woven protective cover. The yarn core carries the load; the cover’s job is to protect the core from abrasion, cuts and UV exposure and is not itself load-bearing. Because the sling has no seams or fixed eyes, it can rotate freely around its own axis during a lift, distributing wear across the whole loop rather than concentrating it at one point — a practical advantage over slings with fixed contact points.
Every round sling must carry a permanent, legible label, typically on a tab sewn into the cover, stating the Working Load Limit for straight, choke and basket hitches, the manufacturer, a traceability reference, and colour coding that indicates the WLL band for a straight vertical lift. Polyester round slings are colour-coded under EN 1492-2: violet for 1 tonne, green for 2 tonnes, yellow for 3 tonnes, grey for 4 tonnes, red for 5 tonnes, brown for 6 tonnes, blue for 8 tonnes, and orange for 10 tonnes. This colour coding is a useful visual aid for quick identification on site, but it is not a substitute for the label — the label governs the sling’s actual rated capacity, and a sling with an unreadable or missing label must be taken out of service regardless of its cover colour.
Before use, inspect for:
- Cuts, holes or fraying in the outer cover, which — even though the cover is not load-bearing — expose the core yarn to abrasion, dirt and UV damage
- Any sign of the core protruding through the cover, or the cover sliding and bunching, which usually indicates internal damage
- Discolouration, stiffness, or melting suggesting chemical or heat exposure
- An illegible, missing or detached label
- Signs the sling has been knotted or twisted in a way not intended by the manufacturer
Because the load-bearing yarn is hidden, any doubt about a round sling’s internal condition should be resolved by a competent person, not assumed safe from the outer cover’s appearance alone.
Standarder: EN 1492-2 (Textile slings — Round slings made of man-made fibres for general purpose use)