Selection for Service Condition
| Service Condition | Stud Bolts | Nuts | Working Temperature °C |
|---|---|---|---|
| High Pressure High Temperature | ASTM A193 Gr B6, B7, B7M B16 | ASTM A194 Gr 2H, 2HM 4 or 7 | 0-480°C 50-450 50-450 |
| High Pressure High Corrosive | ASTM A193 Gr B8, B8M, B8T | 8, 8M, 8T | 540-800 |
| High Pressure Low Temperature | ASTM A320 Gr L7, L7M | ASTM A194 Gr 4 or 7, 7M | 100-50 |
| High Pressure Low Temperature | ASTM A193 Gr B8, B8A | ASTM A194 Gr 8, 8A | 100-250 |
ASTM.SAE-Standards-Chemical-Requirements-in %
| Grades | Material | Range | C | Mn | P | S | Si | Cr | Ni | Mo | Ti | Va | Al |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| B6 | 12% Chromium | Min | 0.08 | 11.50 | |||||||||
| Max | 0.15 | 1.00 | 0.040 | 0.030 | 1.00 | 13.50 | |||||||
| B7/B7M | Chromium, M OLY | Min | 0.38 | 0.75 | 0.15 | 0.80 | 0.15 | ||||||
| Max | 0.48 | 1.00 | 0.035 | 0.040 | 0.35 | 1.10 | 0.25 | ||||||
| B16 | Chrom, Moly, Vanadium | Min | 0.36 | 0.45 | 0.15 | 0.80 | 0.50 | 0.25 | |||||
| Max | 0.47 | 0.70 | 0.035 | 0.040 | 0.35 | 1.15 | 0.65 | 0.35 | 0.015 | ||||
| L7/L7M | Chromium, Moly | Min | 0.38 | 0.75 | 0.15 | 0.80 | 0.15 | ||||||
| Max | 0.48 | 1.00 | 0.035 | 0.040 | 0.35 | 1.10 | 0.25 | ||||||
| B8/8 | AISI 304 | Min | 18.00 | 8.00 | |||||||||
| Max | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 20.00 | 11.00 | ||||||
| B8M/8M | AISI 316 | Min | 16.00 | 10.00 | 2.00 | ||||||||
| Max | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 18.00 | 14.00 | 3.00 | |||||
| 2H/2HM | Carbon | Min | 0.40 | ||||||||||
| Max | 1.00 | 0.040 | 0.050 | 0.40 | |||||||||
| 7/7M/4 | Chromium, Moly | Min | 0.38 | 0.75 | 0.15 | 0.80 | 0.15 | ||||||
| Max | 0.48 | 1.00 | 0.035 | 0.040 | 0.35 | 1.10 | 0.25 |
Mechanical Properties
| ASTM/SAE Standards | Studs and Bolts (Inches & Metric) | Nut Grades | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Parameters | B6 | B7 | B7M | B16 | L7 | L7M | B8 | B8M | Grade | Hardness |
| UTS Ksi [Mpa] (min) | 110 [760] | 125 [860] | 100 [690] | 125 [860] | 125 [860] | 100 [690] | 75 [515] | 75 [515] | 2H | 24-35 HRC |
| Yield Stress Ksi [Mpa] (min) | 85 [585] | 105 [720] | 80 [550] | 105 [725] | 105 [725] | 80 [550] | 30 [205] | 30 [205] | 2HM | 84-99 HRB |
| Elongation % (min) | 15 | 16 | 18 | 18 | 16 | 18 | 30 | 30 | 7 | 24-35 HRC |
| Reduction % (min) | 50 | 50 | 50 | 50 | 50 | 50 | 50 | 50 | 7M | 84-99 HRB |
| Hardness | 35 HRC (Max) | 96 HRB (Max) | 35 HRC (Max) | 35 HRC (Max) | 96 HRB (Max) | 96 HRB (Max) | 96 HRB (Max) | 8 | 60 HRB (min) | |
| Impact | 27J (min) | 27J (min) | 8M | 60 HRB (min) | ||||||
| IS 1367 Part-3 / ISO /DIN | Bolts, Screws and Studs | Nut Grades | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Parameters | 4.6 | 4.8 | 5.6 | 5.8 | 6.8 | 8.8 d≤16mm | 8.8 d>16mm | 10.9 | 12.9 | Grade | Hardness |
| Tensile Strength [N/mm²] (min) | 400 | 420 | 500 | 520 | 600 | 800 | 830 | 1040 | 1220 | 04 | 188-302 HV |
| Yield Stress [N/mm²] (min) | 240 | 340 | 300 | 420 | 480 | 640 | 660 | 940 | 1100 | 05 | 272-353 HV |
| Elongation % (min) | 22 | 20 | – | – | 12 | 12 | 9 | 8 | 5 | 130-302 HV | |
| Reduction % (min) | – | – | – | – | – | 52 | 48 | 44 | 6 | 150-302 HV | |
| Rockwell Hardness | 67-95 HRB | 71-95 HRB | 79-95 HRB | 82-95 HRB | 89-99.5 HRB | 22-32 HRC | 23-34 HRC | 32-39 HRC | 39-44 HRC | 8 | 200-302 HV & 233-353 HV |
| Birnell Hardness | 114-209 HBW | 124-209 HBW | 147-209 HBW | 152-209 HBW | 181-238 HBW | 245-316 HBW | 250-331 HBW | 316-375 HBW | 380-429 HBW | 10 | 272-353 HV |
| Impact KU J (min) | – | – | 27 | – | – | 27 | 27 | 27 | – | 12 | 272-353 HV |
Special Materials
| Grades | Material | Range | C | Mn | Si | P | S | Ni | Cr | Mo | Cu | Nb+Ta | Fe | Ti | Co | Al | B |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| B637 UNS N07718 | INCONEL | Min | 50.00 | 17.00 | 2.80 | 4.75 | REM | 0.65 | 0.20 | ||||||||
| Max | 0.080 | 0.35 | 0.35 | 0.015 | 0.015 | 55.00 | 21.00 | 3.30 | 0.30 | 5.50 | 1.15 | 1.00 | 0.80 | 0.006 | |||
| B865 UNS N0550 | MONEL K500 | Min | 63.00 | 27.00 | 0.35 | 2.30 | |||||||||||
| Max | 0.18 | 1.50 | 0.50 | 0.010 | 33.00 | 2.00 | 0.85 | 3.15 | |||||||||
| B 473 UNS N08020 | ALLOY 20 | Min | 32.00 | 19.00 | 2.000 | 3.000 | 8XC | ||||||||||
| Max | 0.070 | 2.00 | 1.00 | 0.045 | 0.035 | 38.00 | 21.00 | 3.000 | 4.000 | 1.000 |