A193 B8 Stud Bolt
A193 B8 Stud Bolt
Manufacturers:
ASTM A193 Grade B8 studs are manufactured from AISI 304 stainless steel, and tested to meet A193. Dimensional specifications are governed by ASME B18.31.2. Grade markings consists of both the grade symbol "B8" and the manufacturer's identification mark on one end of each stud 3/8" diameter and larger. Manufacturer's marking may be placed on other end if insufficient space. A193 grade B8 all thread studs having diameters above 1" are most common 8UN (8 threads per inch). For use in pressure vessels, valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications. A320 grade B8 studs available for low temperature service.
Products
Stud Flange Charts
| FLANGE | NOMINAL PIPE DIAMETER | ||||||||||
| CLASS | BOLTING | 1/2 | 3/4 | 1 | 1-1/4 | 1-1/2 | 2 | 2-1/2 | 3 | 3-1/2 | 4 |
| 150# | Number | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 8 | 8 |
| Diameter | 1/2 | 1/2 | 1/2 | 1/2 | 1/2 | 5/8 | 5/8 | 5/8 | 5/8 | 5/8 | |
| Stud Bolt Length | 2-1/4 | 2-1/2 | 2-1/2 | 2-3/4 | 2-3/4 | 3-1/4 | 3-1/2 | 3-1/2 | 3-1/2 | 3-1/2 | |
| Mach Bolt Length | 2 | 2 | 2-1/4 | 2-1/4 | 2-1/2 | 2-3/4 | 3 | 3 | 3 | 3 | |
| 300# | Number | 4 | 4 | 4 | 4 | 4 | 8 | 8 | 8 | 8 | 8 |
| Diameter | 1/2 | 5/8 | 5/8 | 5/8 | 3/4 | 5/8 | 3/4 | 3/4 | 3/4 | 3/4 | |
| Stud Bolt Length | 2-1/2 | 3 | 3 | 3-1/4 | 3-1/2 | 3-1/2 | 4 | 4-1/4 | 4-1/4 | 4-1/2 | |
| Mach Bolt Length | 2-1/4 | 2-1/2 | 2-1/2 | 2-3/4 | 3 | 3 | 3-1/4 | 3-1/2 | 3-3/4 | 3-3/4 | |
| 600# | Number | 4 | 4 | 4 | 4 | 4 | 8 | 8 | 8 | 8 | 8 |
| Diameter | 1/2 | 5/8 | 5/8 | 5/8 | 3/4 | 5/8 | 3/4 | 3/4 | 7/8 | 7/8 | |
| Stud Bolt Length | 3 | 3-1/2 | 3-1/2 | 3-3/4 | 4-1/4 | 4-1/4 | 4-3/4 | 5 | 5-1/2 | 5-3/4 | |
| 900# | Number | 4 | 4 | 4 | 4 | 4 | 8 | 8 | 8 | - | 8 |
| Diameter | 3/4 | 3/4 | 7/8 | 7/8 | 1 | 7/8 | 1 | 7/8 | - | 1-1/8 | |
| Stud Bolt Length | 4-1/4 | 4-1/2 | 5 | 5 | 5-1/2 | 5-3/4 | 6-1/4 | 5-3/4 | - | 6-3/4 | |
| 1500# | Number | 4 | 4 | 4 | 4 | 4 | 8 | 8 | 8 | - | 8 |
| Diameter | 3/4 | 3/4 | 7/8 | 7/8 | 1 | 7/8 | 1 | 1-1/8 | - | 1-1/4 | |
| Stud Bolt Length | 4-1/4 | 4-1/2 | 5 | 5 | 5-1/2 | 5-3/4 | 6-1/4 | 7 | - | 7-3/4 | |
| 2500# | Number | 4 | 4 | 4 | 4 | 4 | 8 | 8 | 8 | - | 8 |
| Diameter | 3/4 | 3/4 | 7/8 | 1 | 1-1/8 | 1 | 1-1/8 | 1-1/4 | - | 1-1/2 | |
| Stud Bolt Length | 4-3/4 | 5 | 5-1/2 | 6 | 6-3/4 | 7 | 7-3/4 | 8-3/4 | - | 10 | |
| FLANGE | NOMINAL PIPE DIAMETER | ||||||||||
| CLASS | BOLTING | 5 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 24 |
| 150# | Number | 8 | 8 | 8 | 12 | 12 | 12 | 16 | 16 | 20 | 20 |
| Diameter | 3/4 | 3/4 | 3/4 | 7/8 | 7/8 | 1 | 1 | 1-1/8 | 1-1/8 | 1-1/4 | |
| Stud Bolt Length | 3-3/4 | 4 | 4-1/4 | 4-1/2 | 4-3/4 | 5-1/4 | 5-1/4 | 5-3/4 | 6-1/4 | 6-3/4 | |
| Mach Bolt Length | 3-1/4 | 3-1/4 | 3-1/2 | 4 | 4 | 4-1/2 | 4-1/2 | 5 | 5-1/2 | 6 | |
| 300# | Number | 8 | 12 | 12 | 16 | 16 | 20 | 20 | 24 | 24 | 24 |
| Diameter | 3/4 | 3/4 | 7/8 | 1 | 1-1/8 | 1-1/8 | 1-1/4 | 1-1/4 | 1-1/4 | 1-1/2 | |
| Stud Bolt Length | 4-3/4 | 4-3/4 | 5-1/2 | 6-1/4 | 6-3/4 | 7 | 7-1/2 | 7-3/4 | 8 | 9 | |
| Mach Bolt Length | 4-1/4 | 4-1/4 | 4-3/4 | 5-1/2 | 5-3/4 | 6-1/4 | 6-1/2 | 6-3/4 | 7-1/4 | 8 | |
| 600# | Number | 8 | 12 | 12 | 16 | 20 | 20 | 20 | 20 | 24 | 24 |
| Diameter | 1 | 1 | 1-1/8 | 1-1/4 | 1-1/4 | 1-3/8 | 1-1/2 | 1-5/8 | 1-5/8 | 1-7/8 | |
| Stud Bolt Length | 6-1/2 | 6-3/4 | 7-1/2 | 8-1/2 | 8-3/4 | 9-1/4 | 10 | 10-3/4 | 11-1/4 | 13 | |
| 900# | Number | 8 | 12 | 12 | 16 | 20 | 20 | 20 | 20 | 20 | 20 |
| Diameter | 1-1/4 | 1-1/8 | 1-3/8 | 1-3/8 | 1-3/8 | 1-1/2 | 1-5/8 | 1-7/8 | 2 | 2-1/2 | |
| Stud Bolt Length | 7-1/2 | 7-1/2 | 8-3/4 | 9-1/4 | 10 | 10-3/4 | 11-1/4 | 12-3/4 | 13-3/4 | 17-1/4 | |
| 1500# | Number | 8 | 12 | 12 | 12 | 16 | 16 | 16 | 16 | 16 | 16 |
| Diameter | 1-1/2 | 1-3/8 | 1-5/8 | 1-7/8 | 2 | 2-1/4 | 2-1/2 | 2-3/4 | 3 | 3-1/2 | |
| Stud Bolt Length | 9-3/4 | 10-1/4 | 11-1/2 | 13-1/4 | 14-3/4 | 16 | 17-1/2 | 19-1/2 | 21-1/4 | 24-1/4 | |
| 2500# | Number | 8 | 8 | 12 | 12 | 12 | - | - | - | - | - |
| Diameter | 1-3/4 | 2 | 2 | 2-1/2 | 2-3/4 | - | - | - | - | - | |
| Stud Bolt Length | 11-3/4 | 13-1/2 | 15 | 19-1/4 | 21-1/4 | - | - | - | - | - | |
- All dimensions are in inches.
Chemical Properties
| Per ASTM A193/A193M-16 | ||||||||
| Grade | Material | Carbon | Manganese | Phosphorus | Sulfur | Silicon | Chromium | Nickel |
| % by weight | % by weight | % by weight | % by weight | % by weight | % by weight | % by weight | ||
| B8 | 304 Stainless Steel | 0.08 max | 2.00 max | 0.045 max | 0.030 max | 1.00 max | 18.0-20.0 | 8.0-11.0 |
Governing Standards
| ASTM A193 | Covers alloy and stainless steel bolting materials and bolting components for pressure vessels, valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications. |
| ASME B18.31.2 | Covers the complete dimensional and general data for continuous thread, flange studs (stud bolts), and double-end inch-dimensioned studs. |
| ASME B1.1 UNC & UNF Class 2A | Specifies the thread form, series, class, allowance, tolerance, and designation for unified screw threads. |
Grade B8 Stainless Steel Material Marking
Mechanical Properties
| AISI 304 Stainless Steel, Carbide Solution Treated | Per ASTM A193/A193M-16 | ||||
| Material | Tensile Strength |
Yield Strength, 0.2% offset |
Elongation in 4D |
Reduction of Area |
Hardness |
| Min ksi | Min ksi | Min % | Min % | Max | |
| 304 Stainless Steel | 75 | 30 | 30 | 50 | 223 HBW or 96 HRB (1) |
- 1. For sizes 3⁄4 in. in diameter and smaller, a maximum hardness of 241 HBW (100 HRB) is permitted.