ASTM A179 U Bend Tubes

We bend ASTM A179 U Bend Tubes with round, rectangular, square, plus oval cross sections used in medical, automotive, plus electronics industries.

ASTM A179 U-Bending tubes are widely used in Heat-exchangers.
ASTM A179 U-Bending tubes are widely used in Heat-exchangers.

SA 213-T2 u-bended tube drawing
u-bend tube drawing

ASTM A179 U Bend Tubes for heat exchangers applied mostly in oil and gas plants, chemical and petrochemical plants, refineries, power plants and renewable energy plants. Low fin tubes can be supplied in the form of U bends.

U-bent tube sizes (u-bending, u-bend)

Tube Outside Diameter Tube Wall Thickness Bending Radius U Tube Straight “Leg” Length Straight Tube Before U Bending
min. 12,70 mm min. 0,70 mm min. 1,5 x D max. 11 000 mm max. 24 000 mm
max. 31,75 mm max 5,16 mm max. 1 250 mm

Sizes tolerances of U bend tubes are to fullfil the requirements of: ASTM A556 / 556M and DIN 28179

Heat treatment of U bent tubes

Post bending heat treatment by electrical resistance (Joule effect) is applied. The temperature is monitored and controlled during the process. It is possible to perform the heat treatment in a nitrogen atmosphere.

U bent tubes can be tested as follows

All materials are hydro-tested as standard. Stress relieving is carried out in a gas-fired furnace or solution annealed using an induction heat process. We can offer a range of additional testing on request, including dye penetrant and PMI testing.

Bending Type:

Cold Bending and Hot Bending.

Heat Treatment:

After Cold Bending, the bending area needs heat treatment.

ASTM A179 U-Bending tubes
ASTM A179 U-Bending tubes
ASTM A179 Utubes
ASTM A179 Utubes

Material Comparison Tables (ASTM ℃KS, JIS, DIN, BS, NBN, NF, UNI)

A 179 Seamless Cold Drawn Low-C Steel Heat Exchanger and Conderser Tubes


KS/JIS Symbol
KS/JIS Numbe
DIN Type





B.S Grade
NBN Type
NBN Grade
UNI Type
ASTM A179 K01200 STBH 340 / STB 35 D3563 / G3461 St 35.4 1629


  3606 CFS 320   D 37-2 629 (3b) TU 37 C A49-215 (3a) C 14 5462
        St 35.8 17175 1.0305 Plus
DIN 2391 Gutegard C.NBK


U-bend tubes are widely used in heat-exchanger systems. Heat-exchanger equipment on the basis of seamless stainless U-tubes is essential in strategically important and critical fields — nuclear and petrochemical machine building.

"U bend tubes for heat exchangers applied mostly in Oil & Gas plants, Chemical & Petrochemical plants, Refineries, Power plants, Renewable energy plants."
  • Object medium: 10% sodium
  • hydroxide+5% sodium hypochlorite
  • Shell Diameter: ø 800
  • Working Pressure: 1.5mpa
  • Working Temperature: 40º C-90º C
  • Heat Exchange Surface Area: 100M2
  • Material: Gr1\Gr2

We are passionate about pipe bending:

Pipe bend, Bend pipe, Pipe bending, ANSI, ISO, JIS and DIN Standards, Measures 1/2 to 56 Inches.

The bend is used to change the direction of run of advantage is can matach long distance transition requirements,so it is commonly that bends dimension according to customer design. usually,the bends consist of 3D, 5D, 7D and 12D series.

Key Specifications/Special Features:

End bevel: according to the bevel of welding pipe fittings construction all the size can product according to the clients' requiry.

Pipe bend design


Pressure: SCH5 to SCH160

Bending radius(R): R=3D, 5D, 7D and 12D
Bending angle (θ):15°, 30°, 45°, 60°, 90°, 135°, 180°

Outer diamete(D): D≤1800mm
Wall thickness(T): T≤120mm
Straight Length (L): The length between two ends general from 300mm-1500mm


Industrial Processes

Bending, squeezing, pressing, forging, machining and more

Seamless pipe Specification, standard and identification

Seamless pipes are extensively applied for the nuclear device, gas, petrochemical, ship building and boiler industries. Seamless pipes dominates 65% of market share in Chinese boiler industry.


Our team are highly trained and experienced in servicing and producing all types of steel supplies. Whether you've got a large construction project, or need parts for industrial machinery, our team of steel fabrication consultants will ensure that your project is provided with the parts you need, when you need them.

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