The most common stud bolts materials covered by ASTM A193 are..
Chemical Composition
Physical Element | ASTM A193 grade B7 (AISI 4140) | ASTM A193 grade B8 (AISI 304) | ASTM A193 grade B8M (AISI 316) |
Carbon | 0.38-0.48% | 0.08% max | 0.08% max |
Manganese | 0.75-1.00% | 2.00% max | 2.00% max |
Phosphorus, max | 0.035% | 0.045% | 0.045% |
Sulfur, max | 0.040% | 0.030% | 0.030% |
Silicon | 0.15-0.35% | 1.00% max | 1.00% max |
Chromium | 0.80-1.10% | 18.0-20.0% | 16.0-18.0% |
Nickel | absent | 8.0-11.0% | 10.0-14.0% |
Molybdenum | 0.15-0.25% | absent | 2.00-3.00% |
Mechanical Properties
ASTM A193 | Size | Min Tensile Strength, in ksi | Min Yield Strength, in ksi | Min Elongation, in % | RA % min | Max HBW | Max HRC |
ASTM A193 grade B7 | Up to 2.1/2 | 125 | 105 | 16 | 50 | 321 | 35 |
2.5/8-4 | 115 | 95 | 16 | 50 | |||
4.1/8-7 | 100 | 75 | 18 | 50 | |||
ASTM A193 grade B8 Class 1 | All | 75 | 30 | 30 | 50 | 223 | 35 |
ASTM A193 grade B8M Class 1 | All | 75 | 30 | 30 | 50 | 223 | 96 |
ASTM A193 grade B8 Class 2 | Up to 3/4 | 125 | 100 | 12 | 35 | 321 | 35 |
7/8-1 | 115 | 80 | 15 | 35 | |||
1.1/8-1.1/4 | 105 | 65 | 20 | 35 | |||
1.3/8-1.1/2 | 100 | 50 | 28 | 45 | |||
ASTM A193 grade B8M Class 2 | Up to 3/4 | 110 | 95 | 15 | 45 | 321 | 35 |
7/8-1 | 100 | 80 | 20 | 45 | |||
1.1/8-1.1/4 | 95 | 65 | 25 | 45 | |||
1.3/8-1.1/2 | 90 | 50 | 30 | 45 |
The material chosen for the threaded stud and the hex nuts should be compatible. Materials for bolting sets shall be selected based on the process’s working temperatures, as shown in the table below..
TEMPERATURE °C ( °F ) | ||
STUD BOLTS MATERIALS | MIN. | MAX. |
CARBON STEEL | -29 (-20) | 300 (572) |
A193 B7, L7 | -73 (-100) | 400 (752) |
A193 B6 | 0 (32) | 500 (932) |
A193 B8 | -200 (-325) | 575 (1067) |
A193 B16 | 0 (32) | 520 (968) |
A193 B17B | -29 (-20) | 650 (1202) |
A913 Inconel 718 | 0 (32) | 750 (1382) |
A453 Gr. 660 | -29 (20) | 538 (1000) |
Stud bolts can be produced also with "dual certification," i.e. they conform to multiple sets of ASTM standards (A193 B7 stud bolts can meet the requirements of A320 L7; B8 and B8m stud bolts also typically conform to both A193 and A320).
ASTM A453 STUD BOLTS (HIGH-TEMP.)
The ASTM A453 specification covers standards for Grade 660 (Class A, B, C, and D), Grade 651 (Class A and B), Grade 662 (Class A and B), and Grade 665 (Class A and B) of bolting materials, with ten classes of yield strength ranging from 50 to 120 KSI [345 to 827 MPa], for use in high-temperature service such as fasteners, pressure vessels and flanges.
Bolting materials in ASTM A453 are covered rolled, forged, or hot-extruded bars, and also bolts, nuts, screws, washers, studs, and stud bolts.
Materials shall adhere to specified contents of carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, tungsten, titanium, columbium, aluminum, vanadium, boron, and copper.
According to ASTM A453 materials shall be subjected to tension, stress-rupture, and hardness tests. Materials shall conform to yield strength, tensile strength, elongation, reduction of area, Brinell hardness, and Rockwell hardness requirements.
Hardening and solution treatment requirements for each material class are also given. The most common grades under ASTM A453 are..
Chemical Composition
ELEMENT | ASTM A453 Grade 660 | ASTM A453 Grade 651 | ASTM A453 Grade 662 | ASTM A453 Grade 665 | ASTM A453 Grade 668 |
% | % | % | % | % | |
Carbon | 0.08 max | 0.28-0.35 | 0.08 max | 0.08 max | 0.08 max |
Manganese | 2.00 max | 0.75-1.5 | 0.40-1.00 | 1.25-2.00 | 2.00 max |
Phosphorus | 0.040 max | 0.040 max | 0.040 max | 0.040 max | 0.040 max |
Sulfur, max | 0.030 max | 0.030 max | 0.030 max | 0.030 max | 0.030 max |
Silicon | 1.00 max | 0.30-0.80 | 0.40-1.00 | 0.1-0.80 | 1.00 max |
Nickel | 24.0-27.0 | 8.0-11.0 | 24.0-28.0 | 24.0-28.0 | 17.5-21.5 |
Chromium | 13.5-16.0 | 18.0-21.0 | 12.0-15.0 | 12.0-15.0 | 13.5-16.0 |
Molybdenum | 1.00-1.50 | 1.00-1.75 | 2.0-3.50 | 1.25-2.25 | 1.50 max |
Tungsten | - | 1.00-1.75 | - | - | - |
Titanium | 1.9-2.35 | 0.1-0.35 | 1.80-2.10 | 2.70-3.30 | 2.20-2.80 |
Columbium * | - | 0.25-0.6 | - | - | - |
Aluminum | 0.35 max | 0.35 max | 0.25 max | 0.50 max | |
Vanadium | 0.10-0.50 | - | - | 0.50 max | |
Boron | 0.001-0.010 | 0.001-0.010 | 0.01-0.07 | 0.001-0.010 | |
Copper | 0.50 max | 0.50 max | 0.25 max | - |
Mechanical Properties
ASTM A453 Grade | Class | Tensile, Mpa | Yield, Mpa | Elong. %, min | RA %, min |
ASTM A453 Grade 660 | A, B C | 895 min | 585 min | 15 | 18 |
D | 895 min | 725 min | 15 | 18 | |
ASTM A453 Grade 651 | A | 690 min | 485 min | 18 | 35 |
415 min | |||||
B | 655 min | 415 min | 18 | 35 | |
345 min | |||||
ASTM A453 Grade 662 | A | 895 min | 585 min | 15 | 18 |
B | 860 min | 550 min | 15 | 18 | |
ASTM A453 Grade 665 | A | 1170 min | 830 min | 12 | 15 |
B | 1070 min | 830 min | 12 | 15 | |
ASTM A453 Grade 665 | A & B | 895 min | 858 min | 15 | 18 |
ASTM A453 | Class | Solutiona Treatment | Hardening Treatment |
660 | A | 1650 +/- 25 °F [900 +/-14 °C], hold 2 h, min and liquid quench | 1325 +/- 25 °F [720 +/- 14 °C] 16h, air cool |
B | 1800 +/- 25 °F [980 +/-14 °C], hold 1 h, min and liquid quench | 1325 +/- 25 °F [720 +/- 14 °C] 16h, air cool | |
C | 1800 +/- 25 °F [980 +/-14 °C], hold 1 h, min and oil quench | 1425 +/- 25 °F [775 +/- 14 °C] hold 16h, air cool followed by 1200 +/- 25 °F [650 +/- 14 °C], hold 16h, air cool | |
D | 1650 +/- 25 °F [900 +/-14 °C], hold 2 h, min and liquid quench OR | 1325 +/- 25 °F [720 +/- 14 °C] hold 16h, air cool followed by 1200 +/- 25 °F [650 +/- 14 °C], hold 16h, air cool if necessary to achieve properties, second age : 1200 +/- 25 °F [650 +/- 14 °C] hold 16h, air cool |
|
1800 +/- 25 °F [980 +/-14 °C], hold 1 h, min and liquid quench | |||
651 | A | hot-cold worked at 1200 °F[650] min with 15% min reduction in cross-sectional area, stress-relief anneal at 1200 °F [650 °C] min or 4h, min | |
B | hot-cold worked at 1200 °F[650] min with 15% min reduction in cross sectional area, stress-relief anneal at 1350 °F [730 °C] min or 4h, min | ||
662 | A | 1800 +/- 25 °F [980 +/-14 °C], hold 1 h, min and liquid quench | 1350 to 1400 °F [730 to 760 °C], hold 20h, furnace cool to 1200 +/- 25 °F [650 +/- 14 °C], hold 20h, air cool |
B | 1950 +/- 25 °F [1065 +/-14 °C], hold 2 h, min and liquid quench | 1350 to 1400 °F [730 to 760 °C], hold 20h, furnace cool to 1200 +/- 25 °F [650 +/- 14 °C], hold 20h, air cool | |
665 | A | 1800 +/- 25 °F [980 +/-14 °C], hold 3 h, min and liquid quench | 1350 to 1400 °F [730 to 760 °C], hold 20h, furnace cool to 1200 +/- 25 °F [650 +/- 14 °C], hold 20h, air cool |
B | 2000 +/- 25 °F [1095 +/-14 °C], hold 3 h, min and liquid quench | 1350 to 1400 °F [730 to 760 °C], hold 20h, furnace cool to 1200 +/- 25 °F [650 +/- 14 °C], hold 20h, air cool | |
668 | A | 1650 +/- 25 °F [900 +/-14 °C], hold 2 h, min and liquid quench | 1325 +/- 25 °F [720 +/- 14 °C] 16h, air cool |
B | 1800 +/- 25 °F [980 +/-14 °C], hold 1 h, min and liquid quench | 1325 +/- 25 °F [720 +/- 14 °C] 16h, air cool |
A453 Stud Bolts
Time to Rupture and Elongation
Grade | Class | Test Temperature | Stress, Min | Time to Rupture | Elongation | |
Deg F [ Deg C ] | Ksi | Mpa | Min, h* | Min % | ||
660 | A, B & C | 1200 [650] | 56 | 385 | 100 | 5 |
651 | A & B | 1200 [650] | 40 | 275 | 100 | 5 |
662 | A & B | 1200 [650] | 55 | 380 | 100 | 5 |
665 | A | 1200 [650] | 75 | 515 | 100 | 3 |
B | 1200 [650] | 70 | 485 | 100 | 5 |
ASTM A320 STUD BOLTS (LOW-TEMP.)
The ASTM A320 specification covers alloy steel and Stainless Steel stud bolts materials for low-temperature service.
Each alloy under ASTM A320 shall conform to prescribed chemical requirements. The material, as represented by the tension specimens, shall conform to specific requirements in terms of tensile strength, yield strength, elongation, and hardness. The stud bolt material shall meet the prescribed impact energy absorption requirements and the target test temperature.
According to the ASTM A320 specification, manufacturers shall execute at least the following mechanical tests on the material.. impact test, tension test, and hardness test.
The most common stud bolts materials under ASTM A320 are listed below (low-temperature service)..
ASTM A320 Stud Bolts
Mechanical Properties
ASTM A320 Grade | Diameter | Tensile, KSI, min | Yield, KSI, min | Charpy Impact 20-ft-LBF @ temp | Elong, %, min | RA, %, min |
ASTM A320 Grade L7 | Up to 2.1/2 | 125 | 105 | -150° F | 16 | 50 |
ASTM A320 Grade L43 | Up to 4 | 125 | 105 | -150° F | 16 | 50 |
ASTM A320 Grade B8 Class 1 | All | 75 | 30 | N/A | 30 | 50 |
ASTM A320 Grade B8M Class 1 | All | 75 | 30 | N/A | 30 | 50 |
ASTM A320 Grade B8 Class 2 | Up to 3/4 | 125 | 100 | N/A | 12 | 35 |
7/8-1 | 115 | 80 | N/A | 15 | 35 | |
1.1/8-1.1/4 | 105 | 65 | N/A | 20 | 35 | |
1.3/8-1.1/2 | 100 | 50 | N/A | 28 | 45 | |
ASTM A320 Grade B8M Class 2 | Up to 3/4 | 110 | 95 | N/A | 15 | 45 |
7/8-1 | 100 | 80 | N/A | 20 | 45 | |
1.1/8-1.1/4 | 95 | 65 | N/A | 25 | 45 | |
1.3/8-1.1/2 | 90 | 50 | N/A | 30 | 45 |
ASTM A182 STUD BOLTS (Duplex and Super Duplex)
Chemical Composition
C | Mn | Si | P | S | Cr | Mo | Ni | N |
Duplex 2205 (S31803) |
0.03 max |
2.0 max |
1.0 max |
0.03 max |
0.02 max |
min. 21.0 max: 23.0 |
min. 2.5 max: 3.5 |
min. 4.5 max: 6.5 |
Duplex 2205 (S32205) |
0.03 max |
2.0 max |
1.0 max |
0.03 max |
0.02 max |
min. 22.0 max: 23.0 |
min. 3.0 max: 3.5 |
min. 4.5 max: 6.5 |
Mechanical Properties
Grade | Tensile Strength ksi (min) |
Yield Strength 0.2% ksi (min) |
Elongation % | Hardness (HB) MAX |
2205 | 90 | 65 | 25 | 217 |
Physical Properties
Density lbm/in3 |
Electrical Resistivity mW•in |
Thermal Conductivity (BTU/hr•ft•°F) |
Heat Capacity BTU/lbm•°F |
Electrical Resistivity (in x 10-6) |
at 68°F | 0.278 | 27.6 | 8.7 | 0.112 |
at 212°F | 26.1 | 9.2 | 0.119 | 35.4 |
at 392°F | 25.4 | 9.8 | 0.127 | 37.4 |
at 572°F | 24.9 | 10.4 | 0.134 | 39.4 |
Super Duplex Bolts
Chemical Composition
C | Cr | Ni | Mo | N | Others |
0.02 | 25 | 7 | 4 | 0.27 | S=0.001 |
Mechanical Properties
Ultimate Tensile Strength, ksi | 16 min. |
0.2% Offset Yield Strength 0.2%, ksi | 80 min. |
0.1% Offset Yield Strength 0.2%, ksi | 91 min. |
Elongation in 2 inches, % | 15 min. |
Hardness Rockwell C | 32 max. |
Impact Energy, ft.-lbs. | 74 min. |
Physical Properties
Density | lb/in3 | 0.28 |
Modulus of Elasticity | psi x 106 | 29 |
The coefficient of Thermal Expansion | x10-6/°F | 7.2 |
68-212°F/°F | ||
Thermal Conductivity | Btu/h ft °F | 8.7 |
Heat Capacity | Btu/lb/°F | 0.12 |
Electrical Resistivity | W-in x 10-6 | 31.5 |
Refrence.. Blog.Projectmaterials.Com