Project Description

ASTM A178 Welded Steel Boiler and Superheater Tubes

Click to download the details of ASTM A178 Welded Steel Boiler and Superheater Tubes.

click to download pdf button

ASTM A178/A178M, ASME SA178/SA178M is the standard applicable to electric-resistance-welded carbon steel and carbon manganese steel boiler and superheater tubes.

ASTM A178 Standard covers minimum-wall-thickness, electric-resistance-welded tubes made of carbon steel and carbon-manganese steel intended for use as boiler tubes, boiler flues, superheater flues, and safe ends.

SA178 tubing sizes and thicknesses usually furnished to this specification are 1⁄2 to 5 in. [12.7 to 127 mm] in outside diameter and 0.035 to 0.360 in. [0.9 to 9.1 mm], inclusive, in minimum wall thickness. Tubing having other dimensions may be furnished, provided such tubes comply with all other requirements of this specification.


ASTM A178 tubes are a kind of frequently-used tubes in our life, they are mainly used in manufacturing heating pipelines, containers, coal-saving devices, superheaters, arch superheated tube, airway tube etc.

Quick Detail:

Standard: ASTM A178, ASME SA178

Grade: Grade A, Grade C, Grade D

Technique: Electric-Resistance-Welded

Delivery Condition: Annealed, Normalized, Tempered, Heat Treatment, BK, BKS,


Section Shape: Round

Surface Treatment: Varnish

Size: (mm)

OD: 12.7mm to 127mm

Wall thickness: 1.5mm to 6.0mm

Length: 6m-25m

Ends: Plain ends or bevel ends

Test and other terms:

  1. Hydrostatic or Nondestructive Electric Test
  2. Heat Treatment: according to Standard
  3. Surface Condition: According to Standard.
  4. Grain Size: According to standard
  5. Sampling: flattening, flaring, grain size, Marking

Chemical Compositions (%)

ElementGrade A,Grade C,Grade D
Low-Carbon SteelMedium-Carbon SteelCarbon-Manganese Steel
Phosphorus, max0.0350.0350.03
Sulfur, max0.0350.0350.015
Silicon0.01 min


A178 Mechanical Properties

Grade AGrade CGrade 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 50mm, min, %353030
For longitudinal strip tests a deduction for1.50A1.50A1.50A
Each1⁄32-in[0.8mm] decrease in wall thickness below 5⁄16in. [8mm]
From the basic minimum elongation of the following percentage points shall be made


Outside Diameter and Wall thickness Tolerance:

Outside Diameter toleranceWall thickness tolerance
OD < 50±0.05mmS < 4mm±12.5%
OD > 50±1%4–20mm+15/-12.5%


  • Mill test certificates will be issued according to EN10204.3
  • The tubes Shall be Seamless, and the testing shall be as per A 450 / A450M.
  • Application: apply to the heat exchangers, condensers and heat transfer equipment and similar pipe.


  • Packed in wooden box or bundles protected with plastic paper, and suitably protected for sea-worthily delivery or as requested.
  • The Product marking shall include the ASTM A178 or ASME SA178, size, heat no., Lot No. and Manufacture name or logo.

SA178 Tube Inspection

SA178 Tube Inspection

SA178 Tubes Plain End

SA178 Tubes Plain End

ASTM A178 Tube Package

ASTM A178 Tube Package

Get in Touch

If you are interested in our products or service, please contact us now.

Tel.: +86 185 5109 0083 | E-mail:

Send Email

Standard and Product List