ASTM A270 sanitary (hygienic) stainless steel tubing is the standard specification for the welded seamless, and heavily cold worked welded austenitic and ferritic stainless steel sanitary tubing. It includes the stainless steel tube types in seamless and welded ERW, EFW. ASTM A270 sanitary tubing intended applied in the diary and food industry, bio processing equipment, and having special surface finish. ASTM A270 sanitary stainless steel pipe shall be noted below points during manufacturing processes:

1) Seamless steel pipe should not contains any kind of welding processing.

2) Welded steel pipe applied in automatic welding processing, but should not use metal materials as filler.

3) Heavily cold worked (HCW) tubes shall be manufactured by cold working of not less than 35% reduction of thickness of both wall and weld to a welded pipe prior to the final anneal. Filler materials shall be noted added during welding process. The weld shall be 100% radio graphically inspected in accordance with ASME boiler and pressure vessel standards specification.

4) Sanitary pipe could be furnished with hot finished or cold finished at Manufacture’s option.

Hot-treatment methods for ASTM A270 stainless tube

All materials should supply after hot-treatment. Except the for duplex stainless steel materials S31803, S32003, S320205, S32750, N08926 and N08367, in these cases it shall consist of heating the material to a minimum temperature of 1900 ℉ (1040 ℃) and quenching in water or rapid cooling by other means.