Stud bolts A 193 Grades B7
Stud bolts A 193 Grades B7
[ AREAS-960 ]This Grade B7M is heavily utilized in petroleum, Sewage, Water treatment and chemical construction applications. The ASTM standardcovers alloy steel and stainless steel bolting materials for high temperature or high-pressure service. This specification includes fasteners intended for use in pressure vessels, valves, flanges, and fittings. Although, this material is often available in national coarse (UNC) thread pitches, if being used in traditional applications, threads are specified 8 threads per inch (tpi) for diameters above one inch.
Property class | Chemical composition | |||||||||
C. | Mn. | Si. | P. | S. | Cr. | Ni. | Mo. | V. | Ti. | |
B7M | 0.37---0.49 | 0.65---1.10 | 0.15---0.35 | 0.035 max. | 0.04 max. | 0.75---1.20 | --- | 0.15---0.25 | --- | --- |
Class | Diameter, [Inch] | Minimum Tempering Temperature, °C | Tensile Strength, min, MPa | Yield Strength, min, 0.2 % offset, MPa | Elongation in 4D, min, % | Reduction of Area, min, % | Hardness, max |
B7MA Chromium-molybdenum | 4 and under | 1150 | 100 | 80 | 18 | 50 | 235 HB or 99 HRB |
over 4 to 7 | 1150 | 100 | 75 | 18 | 50 | 235 HB or 99 HRB |
Class | Diameter, [mm] | Minimum Tempering Temperature, °C | Tensile Strength, min, MPa | Yield Strength, min, 0.2 % offset, MPa | Elongation in 4D, min, % | Reduction of Area, min, % | Hardness, max |
B7MA Chromium-molybdenum | M100 and under | 620 | 690 | 550 | 18 | 50 | 235 HB or 99 HRB |
over M100 to M180 | 620 | 690 | 515 | 18 | 50 | 235 HB or 99 HRB |
