4 Tonne Duplex Webbing Sling

Plumalti | 4,000 kg WLL | 120mm Width | Grey | BS EN 1492-1 | CE Marked | UKCA Compliant

The Plumalti 4 Tonne Duplex Webbing Sling is a heavy-duty lifting sling designed for lifting structural steelwork, heavy precast concrete elements, large plant components, and bulky building materials. Manufactured from 100% high-tenacity polyester to BS EN 1492-1:2000, the 120mm wide grey-coded sling delivers a Working Load Limit of 4,000 kg in a straight lift — rising to 8,000 kg in a basket hitch configuration. The extra-wide 120mm strap provides the broadest load-bearing surface in the range, distributing the lifting force evenly and minimising pressure on the load's surface. This makes it the sling of choice for lifting heavy, wide, or awkwardly shaped loads where narrower slings would dig in or concentrate pressure. The dual-layer (duplex) construction provides outstanding abrasion resistance and longevity, even under heavy use on demanding commercial construction sites. Each sling is fitted with a blue traceability label displaying the serial number, WLL, length, and mode factors. Available in lengths from 2m to 10m.

Technical Specifications

Mode Factors: Straight lift = 4,000 kg | Choke hitch = 3,200 kg | Basket hitch = 8,000 kg. Always check the blue traceability label before use to confirm the correct mode factor for your lift configuration.

Key Features

• Manufactured to BS EN 1492-1:2000 — produced from 100% high-tenacity polyester, tested and certified to the European harmonised standard for flat woven webbing slings
• Duplex (two-layer) construction — two layers of woven polyester stitched together provide superior strength, durability, and abrasion resistance for the most demanding lifting operations
• Grey colour-coded for 4 Tonne WLL — instant visual identification of Working Load Limit in accordance with the international colour standard, critical for safe sling selection on busy sites
• 120mm extra-wide strap — the widest sling in the standard range, distributing the lifting force over the greatest possible bearing area to minimise load surface damage and sling wear
• 8,000 kg capacity in basket hitch — in a basket configuration the effective WLL doubles, making this sling capable of handling very heavy structural and precast elements
• 28,000 kg minimum breaking strength — the 7:1 safety factor means this sling is tested to withstand 28 tonnes before failure, providing an exceptional safety margin
• Soft, non-marking polyester — protects painted steelwork, architectural cladding, polished concrete, and finished surfaces from scratching and impact damage during crane operations
• Blue traceability label — individually serialised with WLL, length, mode factors, and manufacturer details for full LOLER inspection traceability and site audit compliance
• Low elongation (max 3%) — predictable load behaviour under tension, with minimal stretch for controlled positioning of heavy components
• Resistant to water, oil, and most common construction chemicals — polyester maintains full rated capacity in wet conditions and resists degradation from hydraulic oil, diesel, and cement residue

Suitable Applications

The 4 Tonne Duplex Webbing Sling is designed for the heaviest lifting duties where a soft, non-marking sling is required. On commercial construction sites, it handles structural steel beams, heavy precast concrete beams and columns, large cladding panels, curtain wall sections, and heavy plant components delivered by tower crane. Civil engineering and infrastructure projects use 4 tonne slings for lifting large-diameter pipes, heavy reinforcement cages, bridge deck elements, and utility transformers. In manufacturing and heavy engineering, the sling positions large machinery, fabricated assemblies, and heavy raw materials where surface protection is essential. The 120mm width is particularly suited to wide loads such as concrete panels, large timber sections, and bulky packaged materials where a narrower sling would concentrate pressure and risk cutting into the load. In a basket hitch, the 8,000 kg effective capacity handles loads that would otherwise require chain slings — but with the surface protection that only webbing can provide.

Lifting Plan Considerations for Heavy Loads

1. Confirm load weight — weigh or calculate the load accurately. Do not estimate. For asymmetric loads, determine the centre of gravity and plan sling positioning accordingly.
2. Select the correct sling configuration — a straight lift uses the full 4,000 kg WLL. A choke hitch reduces this to 3,200 kg. A basket hitch increases it to 8,000 kg. Choose the configuration that matches your load weight and lifting geometry.
3. Check sling angles — in multi-sling lifts, the angle between sling legs must not exceed 120°. As the angle widens, sling loading increases exponentially. Keep angles below 90° wherever possible.
4. Assess edge protection requirements — at 4 tonne loads, even moderate edge sharpness can cut through webbing under tension. Always fit protective corner sleeves or heavy-duty wear pads at contact points with steel edges, concrete corners, and fabricated sections.
5. Consider dynamic loading — wind, sudden stops, and swinging loads create dynamic forces that can momentarily exceed the static load weight. Account for dynamic factors in your lift plan, particularly for tower crane operations in exposed locations.
6. Document the lift — for routine lifts of defined loads, record the lift plan and sling selection. For non-routine, heavy, or complex lifts, prepare a formal lifting plan and risk assessment with input from the Appointed Person.

Certification and Compliance

This product is CE marked in accordance with EU Machinery Directive 2006/42/EEC and is UKCA compliant for the Great Britain market. Manufactured to the performance requirements of BS EN 1492-1:2000 — the European harmonised standard for flat woven webbing slings used in general purpose lifting operations. Each sling is produced with a 7:1 safety factor, individually serialised, and supplied with full traceability documentation including WLL, length, mode factors, and manufacturer identification. All lifting equipment used on UK construction sites must comply with the Lifting Operations and Lifting Equipment Regulations 1998 (LOLER) and the Provision and Use of Work Equipment Regulations 1998 (PUWER). The sling's blue traceability label provides the information required for LOLER thorough examination records.

Safety Information

• Never exceed the rated Working Load Limit (WLL) for the selected hitch configuration. A choke hitch reduces the WLL to 3,200 kg — check mode factors before every lift.
• Inspect the sling before every use. At 4 tonne capacity, even minor damage to the webbing or stitching can have serious consequences under heavy load.
• Always use protective corner sleeves or heavy-duty wear pads when lifting loads with sharp or abrasive edges. At full load, edge damage occurs rapidly and can lead to catastrophic sling failure.
• Do not knot or twist the sling to shorten it. Knotting reduces the WLL by up to 50% and is never acceptable on a 4 tonne rated sling.
• In multi-sling lifts, ensure the included angle between sling legs does not exceed 120°. At angles above 90°, the load on each individual sling increases rapidly.
• Do not expose polyester webbing slings to acids, bleaches, or strong alkalis. While polyester resists most common construction chemicals, concentrated chemical exposure can compromise the fibres.
• Never stand under a suspended load. At 4 tonne capacity, a dropped load represents extreme risk of fatal injury. Maintain exclusion zones during lifting operations.
• A formal lifting plan and risk assessment must be in place before any heavy lifting operation. All personnel involved must be competent and briefed on the lift plan.

Inspection and Maintenance

Webbing slings must be visually inspected before each use and undergo a thorough examination at least every six months (or in accordance with an examination scheme) by a competent person under LOLER 1998. For 4 tonne slings used in heavy-duty applications, more frequent thorough examinations may be appropriate depending on usage intensity. All inspections must be documented and records retained. Inspection should cover the full length of the webbing on both faces, all stitching zones (load-bearing seams are sewn with contrasting thread for easier inspection), both eye areas including any wear sleeves, and the condition and legibility of the blue traceability label. Pay particular attention to areas that contact the load — abrasion damage is most concentrated at bearing points. Any sling showing signs of damage must be removed from service immediately. Webbing slings cannot be field-repaired — damaged slings must be cut and disposed of to prevent re-use.

Frequently Asked Questions