Dimensions from Stud Bolts are defined in the ASME B16.5 standard. The material qualities for studs are defined in the different ASTM standards, and are indicated by Grade. Frequently used grades are A193 for thread rods and A194 for the nuts.
ASTM A193 covers alloy and stainless steel bolting material for pressure vessels, Valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications.
ASTM A194 covers a variety of carbon, alloy, and martensitic and austenitic stainless steel nuts. These nuts are intended for high-pressure or high-temperature service, or both.
Below a table with materials and grades for flanges, thread rods (bolts) and nuts, arranged on design temperature, flanges, thread rods and recommended nuts.
| DESIGN TEMP. |
FLANGES | GRADE THREAD RODS |
GRADE NUTS |
| -195° to 102°C | ASTM A182 Gr. F304, F304L, F316, F316L, F321, F347 |
A320 Gr.B8 Class2 | A194 Gr.8A |
| -101° to -47°C | ASTM A350 Gr.LF3 |
A320 Gr.L7 | A194 Gr.7 |
| -46° to -30°C | ASTM A350 Gr.LF2 |
A320 Gr.L7 | A194 Gr.7 |
| -29° to 427°C | ASTM A105 | A193 Gr.B7 | A194 Gr.2H |
| 428° to 537°C | ASTM A182 Gr.F11, F22 |
A193 Gr.B16 | A194 Gr.2H |
| 538° to 648°C | ASTM A182 Gr.F11, F22 |
A193 Gr.B8 Class1 | A194 Gr.8A |
| 649° to 815°C | ASTM A182 Gr. F304H, F316H |
A193 Gr.B8 Class1 | A194 Gr.8A |
| DESIGN TEMP. |
FLG'S | GRADE THREAD RODS |
GRADE NUTS |
