Stretch is the degree of a material to which it is able to be lengthened by pulling and a critical factor to be considered in order to get as low a stretch under load as possible. All wire rope will have some degree of wire rope stretch.
Wire rope stretch can be of two types:
1. Structural – Of a permanent character. Caused when the initial load is applied.
2. Elastic (ES) – Given by the applied load (kN), wire length (m), modulus of elasticity of wire and it’s cross sectional area ( diameter2 x Pi/4 )
It is possible to calculate this value from the formula:
ES = Applied load (kN) x wire length (m)
Modulus of elasticity x Cross sectional area
Blue Wave has in-house pre-stretching facilities.
Wire rope pre-stretching is normally required for large diameter wire rope, normally 8mm and over, for applications such as:
- Suspension bridges
- Shade structures – carpark shade sails
- Structural shade membranes – sporting stadium roofing
Need a very long cable? We can test up to an unlimited length.
Not a problem, we can test up to 20 metres in one section however the unique design allows for testing up to any length of cable as the cable can be tested in sections by passing it through the hydraulic cable grips and testing each subsequent section.
Need a large diameter cable tested?
Our machine will test up to 32mm diameter wire rope.