A-178 Covers electric resistance welded tubes made of low-carbon steel and intended for use as boiler tubes and superheater flues. SAE J525 Standard covers normalized electric-resistance welded, cold-drawn, single-wall, low-carbon steel pressure tubing intended for use as pressure lines and in other applications requiring tubing of a quality suitable for bending, flaring, forming, and brazing.
Typical Chemical Properties
Carbon % |
0.06 – 0.18 |
Manganese, % |
0.27 – 0.63 |
Phosphorous, Max, % |
0.035 |
Sulfur, Max, % |
0.035 |
Typical Mechanical Properties
Tensile Strength Min |
45 ksi (310 Mpa) |
Yield Strength Min |
24.6 ksi (170 Mpa) |
Elongation Min |
35% |
Hardness Min |
65 HRB |
Typical Permissible Variations in Wall Thickness
All wall thickness |
+20% / 0% |
Typical Permissible Variations in Outside Diameter
Outside Diameters Under 1.000" |
+0.004" / -0.004" |
Outside Diameters 1.000" – 1.500" inclusive |
+0.006" / -0.006" |
Outside Diameters 1.501" – 2.000" |
+0.008" / -0.008" |
Outside Diameters 2.001" – 2.500" |
+0.010" / -0.010" |
Outside Diameters 2.501" – 2.999" |
+0.012" / -0.012" |
Outside Diameters 3.000" – 4.000" |
+0.015" / -0.015" |
Information provided is “Typical” for specific requirements please inquire.