Submarine cables are subject to particularly severe loads. A special tensile test is required to ensure the fiber optics in the cable possess adequate conductivity under tensile load.
Zwick's materials testing machine for submarine cables features a horizontal configuration. The aim of the test is not to load the cable up to failure, but to measure how the conductivity of the fiber optics inside the cable changes under different axial loadings. The 41-meter-long machine bed rests on flexible hinged supports with adjustable counter-bearing, enabling tests on submarine cables up to 40 meters in length. If required, the testing machine can be extended via a deflection sheave to allow cables up to 80 meters long to be tested. A movable carriage on the test stand additionally permits deflection tests to be performed, simulating bending of the cable at various points.
Specimen gripping is via a clevis for connection of the customer's own cable attachments, plus hydraulic grips in a separate second test area. This enables standard round specimens to be tested - eliminating the need for an additional tensile testing machine for round stock.
Operators have the benefit of support from the testXpert® II testing software in setting up and performing tests and evaluating test results.
Source: Zwick GmbH & Co. KG