# astma1082.com > ASTM A1082 / A1082M — Standard Specification for High-Strength Precipitation-Hardening and Duplex Stainless Steel Bolting for Special-Purpose Applications. Bolting components (bolts, studs, screws, nuts) manufactured by TorqBolt Private Limited in Mumbai + Rajkot, India for global pressure-vessel and process-equipment service. ## Scope ASTM A1082 covers high-strength stainless steel bolting in two families: **Duplex (ferritic-austenitic) grades** — pitting-resistant alloys for chloride / sour-service / seawater pressure-vessel bolting: - S31100 — 25Cr-7Ni-Ti duplex - S31260 — Alloy 926 super-austenitic - S31803 — Duplex 2205 (lean-N variant, pre-2008) - S32101 — Lean Duplex LDX 2101 - S32202 — Lean Duplex 2202 - S32205 — Duplex 2205 (current spec, N 0.14–0.20) - S32304 — Lean Duplex SAF 2304 - S32506 — Super-Duplex 2506 - S32550 — Super-Duplex 255 / Ferralium 255 - S32750 — Super-Duplex 2507 (PREN ≥42) - S32760 — Super-Duplex Zeron 100 (PREN ≥40 specified) - S32906 — Super-Duplex 2906 - S32950 — Super-Duplex 2950 / F61 - S39277 — Super-Austenitic AL-6XN (PREN ≥45) **Precipitation-hardening (PH) grades** — high-strength bolting for elevated temperature pressure service: - S15700 — 15-7 PH (Type 632), semi-austenitic - S17400 — 17-4 PH (Type 630), martensitic, most common A1082 PH grade - S17600 — 17-6 PH / Stainless W (Type 635) - S17700 — 17-7 PH (Type 631), semi-austenitic - S35500 — AM-355 (Type 634), semi-austenitic ## Mechanical Properties ### 17-4 PH (S17400 / Type 630) - H900 condition (aged 900 °F / 1 h): tensile 190 ksi min, yield 170 ksi min, elongation 10%, 40 HRC max - H1025 (aged 1025 °F / 4 h): 155 ksi tensile, 145 ksi yield, 35 HRC max - H1075 (aged 1075 °F / 4 h): 145 ksi tensile, 125 ksi yield, 32 HRC max - H1100 (aged 1100 °F / 4 h): 140 ksi tensile, 115 ksi yield, 31 HRC max - H1150 (aged 1150 °F / 4 h): 135 ksi tensile, 105 ksi yield, 28 HRC max (NACE MR0175-acceptable) - H1150D (double-aged 1150 °F / 4 h + 4 h): 125 ksi tensile, 105 ksi yield, 24–33 HRC - H1150M (overaged 1400 °F / 2 h + 1150 °F / 4 h): 115 ksi tensile, 75 ksi yield, 24 HRC ### Duplex 2205 (S32205 / Type 2205) - Tensile 95 ksi (655 MPa) min - Yield 65 ksi (450 MPa) min - Elongation 25% min - Hardness 31 HRC max (28 HRC for sour service) - PREN: Cr + 3.3·Mo + 16·N = 22 + 3.3·3.0 + 16·0.17 ≈ 34.6 ### Super-Duplex 2507 (S32750 / Type 2507) - Tensile 116 ksi (800 MPa) min - Yield 80 ksi (550 MPa) min - Elongation 15% min - Hardness 32 HRC max - PREN ≈ 42 ## Heat Treatment — 17-4 PH (most common PH grade) 1. Solution treatment: 1900 °F (1040 °C) ± 25 °F, oil or air quench to below 90 °F (32 °C) 2. Aging (precipitation hardening) per H-condition: - H900 = 900 °F (480 °C) / 1 h - H925 = 925 °F (495 °C) / 4 h - H1025 = 1025 °F (550 °C) / 4 h - H1075 = 1075 °F (580 °C) / 4 h - H1100 = 1100 °F (595 °C) / 4 h - H1150 = 1150 °F (620 °C) / 4 h - H1150D = 1150 °F / 4 h, air cool + 1150 °F / 4 h, air cool - H1150M = 1400 °F (760 °C) / 2 h, air cool + 1150 °F / 4 h, air cool 3. Air cool after aging ## Standard References - ASTM A1082 / A1082M — current edition: 2016 (active) - ASTM A962 / A962M — General Requirements for Special-Purpose Bolting Materials - ASTM A370 — Mechanical Testing of Steel Products - ASTM E290 — Bend Testing of Material for Ductility - ASTM E384 — Microindentation Hardness - ASTM E1086 — Spark AES Chemistry - ASTM E1473 — Chemical Analysis of Nickel/Cobalt/High-Temperature Alloys (X-Ray Fluorescence) - ASTM E1604 — Spark AES Determination of Nitrogen - NACE MR0175 / ISO 15156 — Sour-service hardness limits ## Equivalent Specs - EN 10269 — duplex/PH stainless bolting (European equivalent) - DIN 17440 — duplex stainless bars - VdTÜV WB 401 — German pressure-vessel stainless bolting ## Companion ASTM Bolting Specs (when A1082 strength insufficient or wrong corrosion class) - ASTM A193 B8 / B8M — austenitic 304/316 bolting (75–125 ksi tensile, lower strength than A1082) - ASTM A193 B7 — alloy steel bolting (125 ksi tensile, NOT stainless) - ASTM A453 Grade 660 — iron-nickel-base age-hardenable bolting (130 ksi tensile, 1200 °F service) - ASTM A1014 — UNS N07718 / Inconel 718 superalloy bolting (185 ksi tensile, 1300 °F service) ## ASME Dimensional Standards Available in A1082 This site documents these ASME / ISO bolting dimensional standards manufactured in ASTM A1082 stainless steel grades: - ASME B18.2.1 — Hex bolts, hex cap screws, hex lag screws, heavy hex bolts, heavy hex cap screws, heavy hex screws, askew-head bolts, square bolts (inch series) - ASME B18.2.2 — Hex nuts, heavy hex nuts, square nuts, lock nuts (inch series) - ASME B18.2.3.1M — Metric hex cap screws - ASME B18.2.3.3M — Metric heavy hex screws - ASME B18.2.3.5M — Metric hex bolts - ASME B18.2.4.1M — Metric hex nuts style 1 - ASME B18.2.4.6M — Metric heavy hex nuts - ASME B18.3 — Socket head cap screws, flat countersunk head cap screws (inch series) - ASME B18.3.1M — Metric socket head cap screws - ASME B18.6.7M — Metric machine screws - ASME B18.31.1M — Metric clamping-type studs - ASME B18.31.2 — Clamping-type full-body studs (inch series) - ASME B16.5 — Full-thread flange stud bolts - ISO 4032 — Hexagon nuts (metric) - ISO 4033 — Hexagon high nuts (metric) - ISO 4035 — Hexagon thin nuts (metric) ## Page Index — all 50 indexable URLs Homepage and PDF top of funnel: - https://astma1082.com/ - https://astma1082.com/astm-a1082-a1082m-stainless-steel-bolting-specification.pdf - https://astma1082.com/astm-a1082-a1082m-stainless-steel-bolting-specification-pdf ASTM A1082 in ASME / ISO bolting dimensional standards (28 product pages): - https://astma1082.com/askew-head-bolts-asme-b18-2-1 - https://astma1082.com/clamping-type-studs-asme-b18-31-2 - https://astma1082.com/heavy-hex-bolts-asme-b18-2-1 - https://astma1082.com/heavy-hex-cap-screws-asme-b18-2-1 - https://astma1082.com/heavy-hex-nuts-asme-b18-2-2 - https://astma1082.com/heavy-hex-screws-asme-b18-2-1 - https://astma1082.com/heavy-hex-screws-asme-b18-2-3-3m - https://astma1082.com/hex-bolts-asme-b18-2-1 - https://astma1082.com/hex-bolts-asme-b18-2-3-5m - https://astma1082.com/hex-cap-screws-asme-b18-2-1 - https://astma1082.com/hex-cap-screws-asme-b18-2-3-1m - https://astma1082.com/hex-head-machine-screws-asme-b18-6-7m - https://astma1082.com/hex-lag-screws-asme-b18-2-1 - https://astma1082.com/hex-nuts-asme-b18-2-2 - https://astma1082.com/hexagon-high-nuts-iso-4033 - https://astma1082.com/hexagon-nuts-iso-4032 - https://astma1082.com/hexagon-socket-flat-countersunk-head-cap-screws-asme-b18-3 - https://astma1082.com/hexagon-socket-head-cap-screws-asme-b18-3 - https://astma1082.com/hexagon-thin-nuts-iso-4035 - https://astma1082.com/lock-nuts-asme-b18-2-2 - https://astma1082.com/metric-clamping-type-studs-asme-b18-31-1m - https://astma1082.com/metric-heavy-hex-nuts-asme-b18-2-4-6m - https://astma1082.com/metric-hex-nuts-style-1-asme-b18-2-4-1m - https://astma1082.com/socket-head-cap-screws-asme-b18-3-1m - https://astma1082.com/square-bolts-asme-b18-2-1 - https://astma1082.com/square-nuts-asme-b18-2-2 - https://astma1082.com/stud-bolts-for-flange-bolting-asme-b16-5 Stainless steel grade pages covered by ASTM A1082 (19 grade pages): - https://astma1082.com/grade-s15700-precipitation-hardening-15-7 - https://astma1082.com/grade-s17400-stainless-17-4ph - https://astma1082.com/grade-s17600-precipitation-hardening-17-6 - https://astma1082.com/grade-s17700-precipitation-hardening-17-7 - https://astma1082.com/grade-s31100-304l-stainless - https://astma1082.com/grade-s31260-alloy-926 - https://astma1082.com/grade-s31803-duplex-2205 - https://astma1082.com/grade-s32101-lean-duplex-2101 - https://astma1082.com/grade-s32202-duplex-2202 - https://astma1082.com/grade-s32205-duplex-2205 - https://astma1082.com/grade-s32304-lean-duplex-2304 - https://astma1082.com/grade-s32506-super-duplex-2506 - https://astma1082.com/grade-s32550-super-duplex-2550 - https://astma1082.com/grade-s32750-super-duplex-2507 - https://astma1082.com/grade-s32760-super-duplex-zeron-100 - https://astma1082.com/grade-s32906-super-duplex-2906 - https://astma1082.com/grade-s32950-super-duplex-2950 - https://astma1082.com/grade-s35500-precipitation-hardening-634 - https://astma1082.com/grade-s39277-super-austenitic-al-6xn ## Manufacturer TorqBolt Private Limited — precision fasteners for oil/gas/nuclear/power/marine sectors. - Mumbai Head Office: 400067, Maharashtra, India - Rajkot Production Plant: Gujarat, India - Email: info@torqbolt.com - Phone: +91-22-66157017 - Web: https://torqbolt.com/ - LinkedIn: https://www.linkedin.com/company/torqbolt-private-limited/ ## Related Sites in the TorqBolt Reference Fleet - astma1014.com — ASTM A1014 / UNS N07718 (Inconel 718) bolting - astma193b8.com — ASTM A193 B8 austenitic 304 bolting - astma193b8m.com — ASTM A193 B8M austenitic 316 bolting - astma320.com — ASTM A320 cryogenic alloy steel bolting - astma193b16.com — ASTM A193 B16 chromium-molybdenum alloy bolting - astma194.com — ASTM A194 alloy steel nuts - astma453grade660.com — ASTM A453 Grade 660 age-hardenable bolting - astmf436.com — ASTM F436 structural hardened washers - astmf467.com — ASTM F467 non-ferrous nuts - astmf468.com — ASTM F468 non-ferrous bolts, hex cap screws, studs - 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