Special Design for Aisi 321 Stainless Steel Pipe - Heat Exchanger Tubes – Donghao Metal Group

Heat exchanger tube in an extensive range of Austenitic, Ferritic and Martensitic stainless steels, duplex stainless steels, nickel alloys, suitable for all types of heat exchangers, such as seawater coolers, condensers, evaporators, heaters and reheaters.

DMG’s heat exchanger tube program includes imperial and metric sizes, from outside diameter 6.35 mm up to 50.8 mm (1/4″ to 2″). Special sizes can be made to order. Our heat exchanger tubes are supplied in straight lengths up to 30 meters, or as U-bent tubes.

Process Method: Cold Drawn/Cold Rolled

Grades:

Austenitic: 304/L, 316L, 317L, 321, 347, 904L,

Martensitic: 410,430, 405, 409, 439, 420, 444, and 446

Duplex: S31803, S32205, S31500, S31200, S32304, S32750

Nickel Alloy: Alloy 400, Alloy 600, Alloy 625, Alloy 800, Alloy 825, Alloy 20, Alloy 28, Alloy C276;

Other grades can be offered on request.

Standards: A213/A269 A789/A790 EN 10216-5 TC1

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.

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).