Special Design for Aisi 321 Stainless Steel Pipe - Tube Bending – Donghao Metal Group

We can supply high quality bend tubes according to customer’s drawings and requirements. We have advanced machines for bending, stress relieve heat treatment, hydrostatic test machine etc, the smallest radius can be 0.5D, our bend tubes are widely used in pressure vessel and boiler plants.

U-BENDING / U bend Tubing / U Tube:

U-BENDING / U bend Tubing / U Tube heat exchangers comprise a U shaped tube fixed by flow baffles or tubes supports and placed in shell to control the fluid present in the exterior of the tube assembly. The fluid is guided into the tubes by a head assembly, which is fixed to the shell by bolts.

Bending Radius: From 1.5 * O.D (outside diameter) ,When ordering tubes with bending radius less than 1.5*OD, it is necessary to get the agreement with us.

Straight tubes maximum length (before bending): 35000 mm.

Leg length: min 1 meter, max. 16500 mm (for max r=1500mm) 

Note: Other sizes are available upon agreement.

Heat treatment: stress relieved after u-bending (bending area plus 300mm for each leg).

Standards: A213/A269, A789/A790, EN 10216-5 TC1, ASME SA – 556/556 m

Outside diameter range from 6.35-50.8mm

Wall thickness range from 0.71-3.81mm

Inspection & Test：

1. 100% PMI / Chemical analysis tests.

2.100% Dimension tests & 100% Visual examination

3. Tension test, flange test, hardness test, flattening test

4. 100% Eddy Test or Hydrostatic Test before bending and 100% Hydrostatic test after bending

5. Checking stress released heat treatment in bending area plus 300mm straight leg length after bending with agreement with clients.

Notes: all the tests and inspection need to provide with reports according to standard and test results.