ASTM A178 ERW Steel Tube Specification

ASTM A178

Standard Overview:

ASTM A178 specifies the requirements for electric resistance welded (ERW) carbon steel and carbon manganese steel boiler and superheater tubes.

Main Material:

The main materials are carbon steel and carbon manganese steel. The designated grades include: Grade A, Grade C and Grade D.

Scope of Application:

This standard applies mainly to high temperature and high pressure. It is for things like boilers, superheaters, and heat exchangers.

Standard	ASTM A178/A178M
Procedure	ERW
Dimensions	12.7mm-127mm, 1/2″-5″
Thickness	0.9mm – 9.1mm
Unit Length	3 – 12 mtrs
Steel Grade	ASTM A178 Gr. A, ASTM A178 Gr. C, ASTM A178 Gr. D
Surface Coating	Black lacquer coating,Varnishing, Oiling, Hot Dip Galvanizing, FBE, 2PP, 3PP, 2PE, 3PE
End Type	Plain, Bevelled, Threaded, Grooved，Shouldered
Joint Method	Fitting, Flange, Coupling, Clamp, Pipe Shoulder, Welding
Pipe Machining	Welding, Bending, Hole Drilling, Punching, Swaging, Tapering, Flaring, Expanding

We offer ASTM A178 boiler tubes in three distinct steel grades:

Mainly used for low temperature and medium pressure boiler and superheater tubes.

Suitable for boiler and superheater tubes at high temperature and high pressure.

Suitable for high temperature and high pressure boiler and superheater tubes.

Outside Diameter：	1⁄2 to 5 in. [12.7 to 127 mm]
Wall Thickness：	0.035 to 0.360 in. [0.9 to 9.1 mm]
Tubing having other dimensions may be furnished, provided such tubes comply with all other requirements of this specification.

Chemical Requirements
Element	Composition, %
	Grade A, Low-Carbon Steel	Grade C,Medium-Carbon Steel	Grade D, Carbon-Manganese Steel


Carbon	0 06–0 18	0 35 max	0 27 max
Manganese	0.27–0.63	0.80 max	1.00– 1.50
Phosphorus, max	0 035	0 035	0 030
Sulfur, max	0.035	0.035	0.015
Silicon	–	–	0. 10 min

Tensile Requirements
Mechanical Properties	Grade A	Grade C	Grade D
Tensile strength, min, ksi [MPa]	47 [325]	60 [415]	70 [485]
Yield strength, min, ksi [MPa]	26 [180]	37 [255]	40 [275]
Elongation in 2 in. or 50 mm, min, %	35	30	30
For longitudinal strip tests a deduction for each 1⁄32-in. [0.8 mm] decrease in wall thickness below 5⁄16 in. [8 mm] from the basic minimum elongation of the following percentage points shall be made.	–	1.50A	1.50A





A See Table 3 for the computed minimum values.

Minimum Elongation Values
Wall Thickness			Elongation in 2 in. or 50 mm, min, %A
OD	in.	mm	Elongation in 2 in. or 50 mm, min, %A
5⁄16	-0.312	8	30
9⁄32	-0.281	7.2	29
1⁄4	-0.25	6.4	27
7⁄32	-0.219	5.6	26
3⁄16	-0.188	4.8	24
5⁄32	-0.156	4	22
1⁄8	-0.125	3.2	21
3⁄32	-0.094	2.4	20
1⁄16	-0.062	1.6	18
A Calculated elongation requirements shall be rounded to the nearest whole number.

ASTM A178 boiler tubes come in sizes tailored to your needs. They can be made with many procedures, including electric resistance welding.
Surface coatings enhance corrosion resistance, and a variety of end types and joint methods are available. Our processing services ensure that the tubes are ready for immediate installation.
UNIASEN’s ASTM A178 boiler tubes Grade C and D meet the tensile requirements. This ensures that the tubes can withstand the tough environments in boilers and superheaters.
Our tubes undergo rigorous testing, including flattening, flanging, stretching, etc., to verify their mechanical integrity.
Every aspect of production is closely monitored and controlled. This includes dimensions and chemical composition.