NATA accreditation officially makes Polysmart Pty Ltd accredited for tensile tests on PE welded products according to ISO 13953, Bend Tests to ISO 21751, and Peel Decohesion Tests on pipe and related products including pipe fittings to ISO 13954.
Membership and NATA recognition ensure that the mechanical testing of PE welded joints and products conducted by the Polysmart laboratory meet a very stringent and demanding set of protocols.
Polysmart’s John Hambridge explained that by meeting NATA standards, those requiring testing can be assured that the Polysmart processes and reporting activities are among the best practices utilised anywhere in the world.
“Clients can be assured that Polysmart test methods meet the exacting requirements of the ISO and also those of the Australian and New Zealand Standards,” explained Mr Hambridge.
Polysmart’s testing services were officially recognised on 10 June 2014, with only a small number of laboratories in Australia offering the same testing services.
Tests are done in a laboratory in accordance with the ISO requirements and under controlled conditions.
Given the increasing use of PE piping in infrastructure and construction, testing of welds has increased over the last few years making NATA accreditation more important than ever for quality assurance reasons.
Weld testing for most projects is therefore important in determining whether quality standards have been met.
“The potential weakness in a pipeline is the welded joint, so the integrity of these welds is of vital importance,” explained Mr Hambridge.
APIA and its Coal Seam Gathering (CSG) code of practice now requires that a number of welds be cut out of existing pipelines, prior to commissioning, and be tested.
Testing shows one of two types of weld failures, either a ductile weld failure or a brittle weld failure.
A ductile weld failure is one that can last longer under a higher amount of force due to the successful fusion between two pipes, showing elongated plastic piping before the weld breaks apart.
A weld test sample failure in the “˜ductile’ mode allows design engineers to have confidence in the long term efficiency of the pipeline and its welded joints.
However, brittle weld failures show a lack of fusion between two pipes, and may “˜snap’ apart easily under pressure.
These welds show limited elongation in comparison to ductile welds, and indicate a lack of fusion that suggest adequate weld or preparation procedures have not been met.
They therefore indicate that the welded pipe may be more susceptible to the influences from tough environmental conditions.
Welds that indicate brittle failures threaten the quality of major projects, and are the reason why testing is so important across industries that use PE welding.
For information on Polysmart training, NATA accredited ISO weld testing services, QCA or inspection services please visit www.polysmart.com.au, phone 1300 36 7659 or email info@polysmart.com.au.