Equipment that is used for supporting her lifting materials, such as load bearing structures and cranes, utilizes rigging comprised of wire or synthetic ropes, or chains. A proof load test is conducted through the process of a lift of a particular material (chain or rope) with the application of a specially designed and manufactured proof load test machine.
The system, when conducting the lift, can measure the load capacity and tensile strength of the material based on the force and resulting elongation. High accuracy hydraulic cylinders are able to produce a dependable measurement of the applied force.
Load Testing Operation
As a measured and controlled application of force within a designated time period, a proof load test involves a mechanism that uses specially designed hydraulic cylinders. The cylinders have separate load cells that produce an accurate reading of the exerted force on the material. The test verifies that the material can handle the maximum allowable working load.
Defining a Working Load Limit
The maximum load that may be applied to lifting equipment without equipment failure is the working load limit. This may be referred to in various ways such as the safe working load, normal working load, maximum allowable working load, and as mentioned originally, working load limit.
Finding the minimum breaking strength of the equipment is not simply what is needed to find the working load limit. The working load limit is a factor involving the minimum breaking strength and the safety factor of the product. Engineers decide the safety factor based on the reliability of particular designs and testing data. The safety factor is a rating that indicates how far beyond standard use conditions equipment can still perform in a safe manner without failure.
A controlled proof load test is implemented to make sure any material, whether it is rigging, chain, synthetic rope, or wire rope, is able to match or exceed the maximum allowable working load.
This test implements hydraulic cylinders that produce a specified force over a determined period of time while the material used for the lift is tested regarding its elongation and ability to keep its shape under the applied force and within the time parameters.
