Related Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Continuously Threaded Inch-Series Stud Bolts for Pipe Flange Bolting in Oil & Gas, Chemical, and Process Piping Systems.
ASME B16.5 Full Thread Stud Bolts are continuously threaded inch-series stud fasteners — threaded from end to end with no unthreaded shank — specified as the standard fastener type for pipe flange bolting in ASME B16.5 pressure piping systems, where their continuous thread allows precise length adjustment to accommodate varying flange thicknesses, insulating gasket kits, orifice flange unions, and different gasket types across flange classes 150 through 2500 and nominal pipe sizes from 1/2 inch to 24 inches. ASME B16.5 provides specific stud bolt diameter and minimum length requirements for every combination of flange size, pressure class, and bolt pattern, ensuring that the stud bolt protrudes the correct amount beyond the nut face after installation to confirm full thread engagement and prevent under-torque bolting errors in the field. When manufactured to ASTM A1082, the specification for high-strength stainless steel bolting material, these full thread stud bolts provide excellent corrosion resistance in aggressive service environments — including offshore topsides and subsea flanges, chemical plant process piping carrying corrosive fluids, coastal pipeline installations, seawater cooling system piping, and chlorine or acid service process lines where carbon steel stud bolts would suffer external atmospheric corrosion and thread seizing in the flange bolt holes. ASTM A1082 stainless steel full thread stud bolts are used with matching stainless steel heavy hex nuts per ASME B18.2.2 or ISO 4032 to form complete, fully corrosion-resistant flange bolting assemblies that maintain their integrity and disassembly capability throughout the full design service life of the piping system. EN 10204 Type 3.1 material certification covering chemical analysis, mechanical testing, and heat treatment is supplied with every ASTM A1082 stud bolt lot for quality-assured project procurement.

| Nominal Size | Diameter, D | Chamfered Thread Distance, U | |||||
|---|---|---|---|---|---|---|---|
| UNC Threads | UNF Threads | 8UN Threads | |||||
| Min. | Max. | Min. | Max. | Min. | Max. | ||
| 1/4 | 6.350 | 1.270 | 2.540 | 0.914 | 1.803 | … | … |
| 5/16 | 7.938 | 1.422 | 2.819 | 1.067 | 2.108 | … | … |
| 3/8 | 9.525 | 1.600 | 3.175 | 1.067 | 2.108 | … | … |
| 7/16 | 11.113 | 1.829 | 3.632 | 1.270 | 2.540 | … | … |
| 1/2 | 12.700 | 1.956 | 3.912 | 1.270 | 2.540 | … | … |
| 9/16 | 14.288 | 2.134 | 4.242 | 1.422 | 2.819 | … | … |
| 5/8 | 15.875 | 2.311 | 4.623 | 1.422 | 2.819 | … | … |
| 3/4 | 19.050 | 2.540 | 5.080 | 1.600 | 3.175 | … | … |
| 7/8 | 22.225 | 2.819 | 5.639 | 1.829 | 3.632 | … | … |
| 1 | 25.400 | 3.175 | 6.350 | 2.134 | 4.242 | … | … |
| 1 1/8 | 28.575 | 3.632 | 7.264 | 2.134 | 4.242 | 3.175 | 6.350 |
| 1 1/4 | 31.750 | 3.632 | 7.264 | 2.134 | 4.242 | 3.175 | 6.350 |
| 1 3/8 | 34.925 | 4.242 | 8.458 | 2.134 | 4.242 | 3.175 | 6.350 |
| 1 1/2 | 38.100 | 4.242 | 8.458 | 2.134 | 4.242 | 3.175 | 6.350 |
| 1 5/8 | 41.275 | … | … | … | … | 3.175 | 6.350 |
| 1 3/4 | 44.450 | 5.080 | 10.160 | … | … | 3.175 | 6.350 |
| 1 7/8 | 47.625 | … | … | … | … | 3.175 | 6.350 |
| 2 | 50.800 | 5.639 | 11.278 | … | … | 3.175 | 6.350 |
| 2 1/4 | 57.150 | 5.639 | 11.278 | … | … | 3.175 | 6.350 |
| 2 1/2 | 63.500 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 2 3/4 | 69.850 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 3 | 76.200 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 3 1/4 | 82.550 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 3 1/2 | 88.900 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 3 3/4 | 95.250 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| 4 | 101.600 | 6.350 | 12.700 | … | … | 3.175 | 6.350 |
| Range, LT | Tolerance |
|---|---|
| From 19.05 through 63.5 | ±1.016 |
| Over 63.5 through 101.6 | ±2.032 |
| Over 101.6 through 203.2 | ±2.540 |
| Over 203.2 through 406.4 | ±3.048 |
| Over 406.4 | ±4.572 |
| Nominal Size | Diameter, D | Chamfered Thread Distance, U | |||||
|---|---|---|---|---|---|---|---|
| UNC Threads | UNF Threads | 8UN Threads | |||||
| Min. | Max. | Min. | Max. | Min. | Max. | ||
| 1/4 | 0.2500 | 0.050 | 0.100 | 0.036 | 0.071 | … | … |
| 5/16 | 0.3125 | 0.056 | 0.111 | 0.042 | 0.083 | … | … |
| 3/8 | 0.3750 | 0.063 | 0.125 | 0.042 | 0.083 | … | … |
| 7/16 | 0.4375 | 0.072 | 0.143 | 0.050 | 0.100 | … | … |
| 1/2 | 0.5000 | 0.077 | 0.154 | 0.050 | 0.100 | … | … |
| 9/16 | 0.5625 | 0.084 | 0.167 | 0.056 | 0.111 | … | … |
| 5/8 | 0.6250 | 0.091 | 0.182 | 0.056 | 0.111 | … | … |
| 3/4 | 0.7500 | 0.100 | 0.200 | 0.063 | 0.125 | … | … |
| 7/8 | 0.8750 | 0.111 | 0.222 | 0.072 | 0.143 | … | … |
| 1 | 1.0000 | 0.125 | 0.250 | 0.084 | 0.167 | … | … |
| 1 1/8 | 1.1250 | 0.143 | 0.286 | 0.084 | 0.167 | 0.125 | 0.250 |
| 1 1/4 | 1.2500 | 0.143 | 0.286 | 0.084 | 0.167 | 0.125 | 0.250 |
| 1 3/8 | 1.3750 | 0.167 | 0.333 | 0.084 | 0.167 | 0.125 | 0.250 |
| 1 1/2 | 1.5000 | 0.167 | 0.333 | 0.084 | 0.167 | 0.125 | 0.250 |
| 1 5/8 | 1.6250 | … | … | … | … | 0.125 | 0.250 |
| 1 3/4 | 1.7500 | 0.200 | 0.400 | … | … | 0.125 | 0.250 |
| 1 7/8 | 1.8750 | … | … | … | … | 0.125 | 0.250 |
| 2 | 2.0000 | 0.222 | 0.444 | … | … | 0.125 | 0.250 |
| 2 1/4 | 2.2500 | 0.222 | 0.444 | … | … | 0.125 | 0.250 |
| 2 1/2 | 2.5000 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 2 3/4 | 2.7500 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 3 | 3.0000 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 3 1/4 | 3.2500 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 3 1/2 | 3.5000 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 3 3/4 | 3.7500 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| 4 | 4.0000 | 0.250 | 0.500 | … | … | 0.125 | 0.250 |
| Range, LT | Tolerances |
|---|---|
| From ¾ through 2½ | ±0.04 |
| Over 2½ through 4 | ±0.08 |
| Over 4 through 8 | ±0.10 |
| Over 8 through 16 | ±0.12 |
| Over 16 | ±0.18 |
ASTM A1082 covers duplex grades (S31803/2205, S32205/2205, S32750/2507, S32760/Zeron 100, S39277/AL-6XN) and precipitation-hardening grades (S17400/17-4 PH, S17700/17-7 PH, S15700/15-7 PH, S35500/AM-355) - all available for this product family at TorqBolt.
This product follows ASME B16.5, the dimensional standard for stud bolts in stainless steel. Material chemistry, mechanical properties and heat treatment follow ASTM A1082/A1082M. TorqBolt supplies both inch-series and metric sizes per the applicable ASME or ISO drawing.
Yes, with hardness control. NACE MR0175 / ISO 15156 permits duplex grades S31803, S32205, S32750, S32760 at 28 HRC max for sour service. 17-4 PH (S17400) at H1150 condition (28 HRC) is the most common PH grade qualified for sour service. TorqBolt provides NACE-MR0175 compliant heat-treat reports.
Super-duplex 2507 (S32750) per A1082: tensile 116 ksi (800 MPa) min, yield 80 ksi (550 MPa) min, elongation 15% min, 32 HRC max. PREN ≈ 42 - suitable for seawater, brine and chloride-rich pressure-vessel service. Higher strength than austenitic A193 B8M while offering pitting resistance well above 304/316.