Technical features and scope of ASTM A778
The ASTM A778 standard regulates the parameters of unannealed welded pipes made from austenitic stainless steel grades. Products supplied by EV Group China are optimized for operation in moderate to low temperature regimes, as well as in environments with high corrosion activity, where specific surface finishing is not a critical requirement.
According to ASTM A778 specifications, the production cycle is based on the use of flat-rolled products (steel sheets or strips), which are formed and welded using automatic or manual arc welding methods in an inert shielding gas environment. If weld defects are detected, EV Group China’s technology provides for the complete removal of metal in the non-conforming zone followed by re-welding, which ensures the integrity of the product structure.
The quality of pipes supplied by EV Group China complies with strict industry requirements: the surface of the products is free of burrs, the ends are prepared for installation, and the geometry meets the specified tolerances. Each batch undergoes mandatory transverse bend and tensile tests. For projects requiring mandatory weld heat treatment or 100% radiographic inspection, our engineers recommend using A312 / A312M, A358 / A358M, or A409 / A409M standards.
EV Group China supplies welded unannealed austenitic steel pipes in a wide size range:
- Outside diameter: from 3 inches (75 mm) to 48 inches (1200 mm).
- Wall thickness: from 0.062 inches (1.57 mm) to 0.500 inches (12.70 mm).
EV Group China specialists are ready to provide products with non-standard dimensions, provided that the physical and chemical requirements of the ASTM A778 standard are fully met.