seamless medium carbon steel tubes
Purpose:
Seamless medium carbon steel tubes with minimum wall thickness for boiler tubes and boiler flue tubes, including safety ends, vaults, support tubes and superheater tubes
Implementation standards:ASTM A210/ASME SA210
The main production grades of steel pipes are as follows:
A/SA210Gr.A-1、A/SA210Gr.C
ASTM A210 / A210M Grade A-1 Chemical Compositions
Chemical Components (%) | ||||||||
Grade | C | Si | Mn | P | S | Mo | Cr | V |
A-1 | ≤0.27 | ≥0.10 | ≤0.93 | ≤0.035 | ≤0.035 | / | / | / |
ASTM A210 / A210M Mechanical Tests Required
Mechanical Properties | ||||
Grade | Tensile Strength (Mpa) | Yield Strength (Mpa) | Elongation (%) | Hardness (HRB) |
A-1 | ≥415 | ≥255 | ≥30 | ≤79 |
ASTM A210 / A210M Tube Wall Thickness Tolerance
Seamless, Cold-Finished Tubes | ||
Outside Diameter In. (mm) | Wall thickness Tolerance % | |
Over (+) | Under (-) | |
1 ½ (38.1) and under | 20 | 0 |
Over 1½ (38.1) | 22 | 0 |
ASTM A210 / A210M Tube Outside Diameter Tolerance
Cold-Finished Seamless Tubes | ||
Outside Diameter In. (mm) | Permissible Variations In. (mm) | |
Over (+) | Under (-) | |
Under 1 (25.4) | 0.004 (0.10) | 0.004 (0.10) |
1 to 1 ½ (25.4 to 38.1), Incl | 0.006 (0.15) | 0.006 (0.15) |
Over 11⁄2 to 2 (38.1 to 50.8), Excl | 0.008 (0.20) | 0.008 (0.20) |
2 to 21⁄2 (50.8 to 63.5), Excl | 0.010 (0.25) | 0.010 (0.25) |
21⁄2 to 3 (63.5 to 76.2), Excl | 0.012 (0.30) | 0.012 (0.30) |
ASTM A210 / A210M Tube Cut Length Tolerance
Cold-Finished Seamless Tubes | ||
Outside Diameter, In.(mm) | Cut Length, in.(mm) | |
Over (+) | Under (-) | |
All Sizes | 3⁄16 [5] | 0 [0] |
Under 2 (50.8) | 1⁄8 [3] | 0 [0] |
2 (50.8) and over | 3⁄16 [5] | 0 [0] |
Under 2 (50.8) | 1⁄8 [3] | 0 [0] |
2 (50.8) and over | 3⁄16 [5] | 0 [0] |
These permissible variations in length apply to tubes before bending. They apply to cut lengths up to and including 24 ft [7.3 m]. For lengths greater than 24 ft [7.3 m], the above over-tolerances shall be increased by 1⁄8 in. [3 mm] for each 10 ft [3 m] or fraction thereof over 24 ft or 1⁄2 in. [13 mm], whichever is the lesser. | ||
ASTM A210 / A210M Tube Hydrostatic Test Pressures
Each tube shall be subjected to the hydrostatic pressure test, or instead of this test, a nondestructive test may be used when specified by the purchaser.
Hydrostatic Test Pressures | |
Outside Diameter of Tube, in. [mm] | Hydrostatic Test Pressure, psi [MPa] |
Under 1 [25.4] | 1000 [7] |
1 to 11⁄2 [25.4 to 38.1], excl | 1500 [10] |
11⁄2 to 2 [38.1 to 50.8], excl | 2000 [14] |
2 to 3 [50.8 to 76.2], excl | 2500 [17] |
ASTM A210 / A210M Flattening Test
One flattening test shall be made on specimens from each end of one finished tube from each lot, but not the one used for the flaring test. Tears or breaks occurring at the 12 or 6 o’clock positions on Grade C tubing with sizes of 2.375 in. [60.3 mm] in outside diameter and smaller shall not be considered a basis for rejection.
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