A193 B7 Stud Bolts
ASTM A193 B7 Stud Bolts are specially designed for flange bolting applications where accurate dimensions, reliable clamping force and long-term fastening performance are required. Unlike general threaded rods that are often supplied as long continuous threaded bars and cut according to installation needs, stud bolts are usually produced as finished components with defined lengths and thread configurations for direct assembly.
Manufactured according to ASTM A193 Grade B7 requirements, these stud bolts are made from chromium-molybdenum alloy steel and are commonly used together with ASTM A194 Grade 2H heavy hex nuts. The matched stud and nut assembly provides stable tightening performance for high pressure and high temperature bolting connections. ASTM A193 B7 Stud Bolts are widely used in flange connections for piping systems, pressure vessels, oil and gas facilities, petrochemical equipment and power generation plants. Depending on project requirements, they can be supplied in different diameters, lengths, thread forms and surface treatments to meet various industrial fastening conditions.
Specification of A193 B7 Stud Bolts:
| Product name | ASTM A193 B7 Stud Bolts |
|---|---|
| Diameter | 1/4″ – 4″ |
| Dimension Standard | ASME B18.31.2 |
| Thread | UNC/UNF/8UN |
| Tension Strength | 125 KSI |
| Compatible nuts/washers | A194 2H Heavy Hex Nuts |
| Manufacturing Process | wire drawing, thread rolling, heat treatment, surface treatment |
| Surface treatment | Black Oxide Coating,Zinc Plating (Electroplating),Hot-Dip Galvanizing,Mechanical Galvanizing,Dacromet Coating |
| Application Industry | Piping Systems/Pressure Vessels/Pressure Vessels/Oil and Gas Industry/Power Generation/Chemical Processing |
- RELATED SCREWS:
- SET SCREWS
- ASME B18.3 Flat Point Set Screws
- ASME B18.3 Oval Point Socket Set Screws
- ASME B18.3 Cup Point Socket Set Screw
- ASME B18.3 Cone Point Set Socket Screws
- ASME B18.3 Half Dog Point Spline Socket Set Screws
- DIN913 Flat Point Set Screws
- DIN915 Dog Point Set Screws
- DIN916 Cup point Socket Set Screws
Dimension Chart of ASTM A193 B7 Stud Bolts:
| Thread Diameter | Thread Per Inch | Chamfered Thread Distance | ||||
|---|---|---|---|---|---|---|
| UNC | UNF | 8UN | UNC | UNF | 8UN | |
| 1/4 | 20 | 28 | - | 0.05-0.1 | 0.036-0.071 | - |
| 5/16 | 18 | 24 | - | 0.056-0.111 | 0.042-0.083 | - |
| 3/8 | 16 | 24 | - | 0.063-0.125 | 0.042-0.083 | - |
| 7/16 | 14 | 20 | - | 0.072-0.143 | 0.05-0.1 | - |
| 1/2 | 13 | 20 | - | 0.077-0.154 | 0.05-0.1 | - |
| 9/16 | 12 | 18 | - | 0.084-0.167 | 0.056-0.111 | - |
| 5/8 | 11 | 18 | - | 0.091-0.182 | 0.056-0.111 | - |
| 3/4 | 10 | 16 | - | 0.1-0.2 | 0.063-0.125 | - |
| 7/8 | 9 | 14 | - | 0.111-0.222 | 0.072-0.143 | - |
| 1 | 8 | 12 | - | 0.125-0.25 | 0.084-0.167 | - |
| 1-1/8 | 7 | 12 | - | 0.143-0.286 | 0.084-0.167 | - |
| 1-1/4 | 7 | 12 | - | 0.143-0.286 | 0.084-0.167 | - |
| 1-3/8 | 6 | 12 | - | 0.167-0.333 | 0.084-0.167 | - |
| 1-1/2 | 6 | 12 | - | 0.167-0.333 | 0.084-0.167 | - |
| 1-5/8 | - | - | 8 | 0.125-0.25 | ||
| 1-3/4 | 5 | - | 8 | 0.2-0.4 | 0.125-0.25 | |
| 1-7/8 | - | - | 8 | 0.125-0.25 | ||
| 2 | 4-1/2 | - | 8 | 0.222-0.444 | 0.125-0.25 | |
| 2-1/4 | 4-1/2 | - | 8 | 0.222-0.444 | 0.125-0.25 | |
| 2-1/2 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 2-3/4 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 3 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 3-1/4 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 3-1/2 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 3-3/4 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
| 4 | 4 | - | 8 | 0.25-0.5 | 0.125-0.25 | |
Chemical Composition:
| Property class | Material and heat treatment | Chemical composition limits (cast analysis, %) a | ||||||
|---|---|---|---|---|---|---|---|---|
| A193 B7 | Alloy steel, AISI 4140/4142 quenched and tempered | Carbon | Manganese | Phosphorus, max | Sulfur, max | Silicon | Chromium | Molybdenum |
| 0.37 - 0.49% | 0.65 - 1.10% | 0.035% | 0.040% | 0.15 - 0.35% | 0.75-1.2% | 0.15 - 0.25% | ||
Mechanical and physical properties:
| Grade | Size | Tensile ksi, min | Yield, ksi, min | Elong, %, min | RA % min | HBW | Rockwell |
|---|---|---|---|---|---|---|---|
| B7 | Up to 2-1/2 | 125 | 105 | 16 | 50 | 321 max | 35 HRC max |
| 2-5/8 - 4 | 115 | 95 | 16 | 50 | |||
| 4-1/8 - 7 | 100 | 75 | 18 | 50 |