Using outrigger pads to meet safety challenges on remote sites

High-stability jobs involving construction, resources infrastructure, exploration, mobile worksite equipment and emergency use require outrigger pads that are designed to be virtually unbreakable and withstand rated loads of more than 50 tonnes per point on a solid foundation. The light, easily handled pads — weighing as little as 14–21 kg for point loads of 40–70 tonnes depending on foundation — are custom-fabricated by Cut To Size Plastics from the Wearex UHMWPE (Ultra-High Molecular Weight Polyethylene) family, in particular shapes required for diverse ground conditions. The strength of UHMWPE comes from its long polymer chains and high molecular weight, which give it some of the greatest impact strength of any thermoplastic that is currently being manufactured, according to Laurie Green, Managing Director of Cut to Size Plastics. Green said that UHMWPE outrigger pads can flex slightly on rough terrain, which protects them from breaking when under stress. Green, who has more than 40 years’ experience in specifying the best engineering plastics for particular jobs, added that less safe materials such as wood are susceptible to breaking and splintering, and they also expand and warp due to moisture absorption, which weakens the pads. “UHMWPE is far longer lasting. Instead of replacing outrigger pads regularly, users get longer and safer lives out of these ultra-tough, ultra-dependable pads in diverse and critical applications,” Green said.

These applications include materials for conditions encountered by truck cranes, rigger cranes, mobile cranes, auxiliary cranes, mobile concrete pumps, manlifts, access equipment, mobile drill rigs, 4WD service vehicles and by machinery used for agribusiness, oil and gas, mining, pipelining, civil engineering and similar applications. The Wearex range is suitable for operations where safety and ergonomics are a key concern, including the transport, lifting and placement of pads and their ability to withstand extreme loads without permanent deformation. Compared with steel plates, they offer high recovery during deformation, making them ready to use for a longer period. “The low weight of Wearex material float pads makes them easier to handle during use and assembly. Ergonomic machined or rope handles can be integrated in pad design. They are easily transportable in 4WDs, diesel trucks and machinery, for example, such as those used across mining, infrastructure, construction and energy sites across diverse and often remote worksites,” Green said.

Cut To Size’s easily handled outrigger pads. The tough, light pads are suitable for both harsh and remote site conditions. Image credit: Cut To Size Plastics

Wearex’s material elasticity makes it sturdy and secure, even with smaller bumps and edges. The Wearex range can also be completely recycled and is resistant against fuels, lubricants and chemicals and suitable for use in high ambient temperature (to a maximum of 90°C) and high moisture applications. Cut To Size’s experience with Wearex extends over a range of environments for which it is suitable, including marine facilities such as ports and oil and gas exploration, through to outback mining and civil engineering and on-site maintenance facilities where fuels and common chemicals are an issue. Wearex pads are also suitable for emergency and remote use, as they are easy to transport and can be placed promptly and precisely for a strong footing, and to prevent sinking into softer ground. Wearex can be used to fabricate portable roads to provide access on unpaved services and to protect sensitive environments such as parklands, grasslands, recreation facilities and damage-prone areas on construction sites where vehicle and machinery access is required. The mechanical properties of typical Wearex outrigger pads include:

• Shore D hardness 15s — Value (Skala D unit, DIN53505 test method) 64-68
• Ultimate tensile strength (N/mm², DIN53455) 30
• Modulus of elasticity (N/mm² DIN 53457) 900
• Application temperature (Min and constant deg C) -200/+80
• Dimensional stability under heat (Deg C DIN53461) 47
• Moisture absorption (%) < 0.01
   

Pads may be custom-manufactured from members of the Wearex family to achieve required performance characteristics. Cut To Size designs and manufactures components for applications across Australasia from its head office in Sydney, where facilities include CNC machining facilities coupled with GibbsCAM and Solidworks software.

Top image credit: Cut To Size Plastics