Chinese wholesale 321 Stainless Steel Tubing - A249 Stainless Steel Welded tube – Donghao Metal Group

DMG’s A249 welded tube program includes imperial and metric sizes, from outside diameter 12.7 mm up to 101.6 mm (1/2″ to 4″). Special sizes can be made to order. Our A249 welded tubes are supplied in straight lengths up to 26 meters, or as U-bent tubes, which suitable for boilers, heat exchangers, condenser, feed-water heaters, cooler, muffler, steamer, juice heater, welling and falling-film evaporators.

Material:

TP304, TP304L, TP316L available from stock;

The wide range of other materials such as TP321, TP347H, TP310S

Duplex,S31803, S32205, S32750, S32760, TP439, titanium can be readily prepared on request.

Standards:

ASTM A249 / A249M Standard Specification for Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser Tubes

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.

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).

Packing:

Sea worthy Bundle or Plywood