Stainless steel mechanical tubes are usually divided into two major categories: welded type and seamless type. The former complies with the ASTM A554 standard. The steel strip is rolled into shape through resistance welding and then welded into tubes, and the external weld bead is removed to obtain a smooth surface. The latter is extruded or perforated from solid stainless steel billets in accordance with standards such as ASTM A632/ A511/ A213, without welds and with higher...