Stainless steel U-tube
1) Diameter: 13.7-273.1
2) Thickness: 1.65-22mm
3) Materials: 304, 304L, 316, 316L, 312, etc.
4) Standard: ASTM A179, ASTM A312, ASTM A213, ASTM A269 etc.
5) Marking: grade, standard, Size, heat No
6) Package: wooden cases or steel box
7) Mill test certificate: EN 10204-3.1B.
8) Payment: T/ T, L/ C

U-tubes are bended according to drawings from cold drawn seamless steel tubes& stainless steel tubes according to standard ASTM A179 or A213.
Heat treatment:
1) Stress relive annealing of U-tubes after bending only for all positions
2) Surface condition finished U-tube shall be free of scale, without scratches after bending.
3) Through ball test
4) 100% Eddy Current tests.

Bending radius as per your drawings
Dimensional tolerances as per standards
Flattening at the bend should not exceed 10% of the norminal tube outerside.