ASME SA-210 SPECIFICATION FOR SEAMLESS MEDIUM-CARBON STEEL BOILER AND SUPERHEATER TUBES
Chemical Composition （max. %）
Element | Grade A-1 | Grade C |
C | 0.27 | 0.35 |
Mn | 0.93 | 0.29-1.06 |
| P | 0.035 | 0.035 |
| S | 0.035 | 0.035 |
| Si | ≥0.10 | 0.10 |
For each reduction of 0.01% below the specified carbon maximum, an increase of 0.06% manganese above the specified maximum will be permitted up to a maximum of 1.35%.
Tensile Requirements
| Element | Grade A-1 | Grade C |
| Tensile strength, min, ksi [MPa] | 60 [415] | 70 [485] |
Yield strength, min, ksi [MPa] | 37 [255] | 40 [275] |
| Elongation in 2 in. or 50 mm, min, % | 30 | 30 |
| For longitudinal strip tests, a deduction shall be made for each 1/32 in. [0.8mm] decrease in wall thickness under 5⁄16 in. [8 mm] from the basic minimum elongation of the following percentage points | 1.50 A | 1.50 A |
| When standard round 2 in. or 50 mm gage length or smaller proportionally sized specimen with the gage length equal to 4D (four times the diameter) is used | 20 | 200.10 |
A See Table below for the computed minimum values.
Wall Thickness, in. [mm] | Elongation in 2 in. or 50 mm, min, % |
5/16 (0.312) [8] | 30 |
| 9/32 (0.281) [7.2] | 28 |
1/4 (0.250) [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 |
| 0.062 to 0.035 [1.6 to 0.9], excl | 17 |
0.035 to 0.022 [0.9 to 0.6], excl | 16 |
| 0.022 to 0.015 [0.6 to 0.4], incl | 16 |
Hardness Requirements
The tubes shall have a hardness not exceeding the following: 79 HRB or 143 HB for Grade A-1, 89 HRB or 179 HB for Grade C.
Mechanical Tests Required
Tension Test
Flattening Test
Flaring Test
Hardness Test
Hydrostatic or Nondestructive Electric Test
