Rotech is celebrating 20 years of collaboration with a leading West Midland based fittings and pipes manufacturer.
Over the course of the past two decades, Rotech has assisted the customer by providing on-site independent UKAS accredited testing, and providing quality assurance of welded duplex austenitic/ferritic stainless-steel plates and pipes to ASTM standards.
The fittings customer is a leading manufacturer of large diameter fittings and bespoke lengths of steels pipes. They supply a wide range of industries including oil, gas, petrochemical and nuclear, so it is imperative that the plates and pipes they manufacture are tested, to ensure any welds are of suitable quality for their intended applications. The welding procedure, or welder technique, is also verified to limit weld failures, which may cause damage to the material, resulting in a loss of strength and durability.
Once Rotech receives the welded specimens, a series of mechanical tests are performed to determine whether a material is suitable for its final application. Included in this testing is the determination of its yield strength, which is often used to determine the maximum allowable load in a mechanical component since it often represents the upper limit that can be applied without producing permanent deformation. Testing also provides the ultimate tensile strength, maximum elongation and reduction in area which allow an assessment as to whether the material meets the requirements of the specification, standard, or contract.
The fittings customer offers their clients high quality products which are manufactured in the UK. To maintain these high standards, and to give quality assurance, they have relied on Rotech as an independent UKAS approved testing laboratory to aid with the below tests:
- Impact testing in accordance with ASTM A370 undertaken by either Charpy or Izod Methods.
- Metallographic micro examination to identify any detrimental phases which could cause adverse effects to the material’s toughness and corrosion resistance. Specimens for micro are cross-sectioned and prepared in accordance with procedure ASTM E3. The surface to be examined is polished and etched in 20% NaOH electrolyte to reveal any ferrite and austenite structures and the microstructure examined at 500 X magnification to identify any detrimental phases that may be present.
- Metallographic volume fraction tests, in accordance with ASTM E562. In this test, a transverse cross section through the specimen was prepared prior to ferrite content determination looking at the Parent metal, HAZ and Weld locations.
- Hardness testing in accordance with ASTM E92 with measurements taken across the weld metal, heat affected zone and base metal.
- Pitting/crevice resistance tests in accordance with ASTM G48 Method A (ferric chloride pitting test) to access the resistance of stainless steels in chloride environments.
Results from the required tests are analysed by Rotech’s team of specialists. The specimens will either pass or fail the requirements to satisfy the ASTM test standards. Undertaking the above tests, and receiving certification by Rotech Laboratories has helped the customer ensure their products are fit for purpose and verified for use in home and international markets.