A flange bolt differs from the common bolt in that it has a wider surface area under the head to provide for an even distribution of clamping pressure. This wider surface acts like a washer, eliminating the need to combine one with this kind of bolt. Flange bolts are available in numerous sizes, strengths, and configurations. Like most other types of fasteners on the market, metric flange bolts are available for any applications that require them.
Specially designed flange bolts are equipped with anti-rotational “teeth” designed to “bite” or dig into the material one might need to fasten together. Similar to the locking rings one might see on a soda bottle or milk jug, these teeth on the flange bolt can be turned backward, but often require more force. This type of design is what makes a flange bolt uniquely and strategically different from a common bolt.
An essential addition to the flange bolt is the flange nut. While it is similar to an ordinary nut, one side of the flange nut is wider than the other to ensure even pressure distribution. The flange nut and flange bolt work well together, and in some cases may reduce costs by eliminating the need for purchasing separate washers. Proper torque on a flange bolt-nut combination will ensure that the fasteners never become loose by themselves. Only an outside force, such as a mechanic, can loosen these types of flange bolts.
Dimensions Flange Bolts, ANSI CLASS 150-2500, 1/16″ AND 1/4″ RAISED FACE AND FLAT FACE (IN) DATASHEET
- Stud bolts in accordance with ANSI/ASME B16.5.
- A stud is threaded either on both ends or the full length of the stud.
- Studs both have American National Course Threads.
- Length of stud bolts do not include the height of the point.
- Length of stud bolts when used with lap joint flanges will depend upon the thickness of the lap joint stub end.
- ANSI 150 Lb. and 300 Lb. weld neck flange has a 1/16 inch raised face.
- ANSI 400 Lb. to 2500 Lb. weld neck flange has a 1/4 inch raised face.
Machine Bolt
Stud Bolt
| Pipe Size (NPS) | Class 150 | Class 300 | Class 400 | Class 600 | Class 900 | Class 1500 | Class 2500 | Pipe Size (NPS) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
# of Bolts |
Bolt Diameter |
Stud Bolt Length |
# of Bolts | Bolt Diameter | Stud Bolt Length | # of Bolts | Bolt Diameter | Stud Bolt Length | # of Bolts | Bolt Diameter | Stud Bolt Length | # of Bolts | Bolt Diameter | Stud Bolt Length | # of Bolts | Bolt Diameter | Stud Bolt Length | # of Bolts | Bolt Diameter | Stud Bolt Length | ||
| 1/2 | 4 | 1/2 | 2 1/4 | 4 | 1/2 | 2 1/2 | 4 | 1/2 | 3 | 4 | 1/2 | 3 | 4 | 3/4 | 4 1/4 | 4 | 3/4 | 4 1/4 | 4 | 3/4 | 4 3/4 | 1/2 |
| 3/4 | 4 | 1/2 | 2 1/2 | 4 | 5/8 | 3 | 4 | 5/8 | 3 1/2 | 4 | 5/8 | 3 1/2 | 4 | 3/4 | 4 1/2 | 4 | 3/4 | 4 1/2 | 4 | 3/4 | 5 | 3/4 |
| 1 | 4 | 1/2 | 2 1/2 | 4 | 5/8 | 3 | 4 | 5/8 | 3 1/2 | 4 | 5/8 | 3 1/2 | 4 | 7/8 | 5 | 4 | 7/8 | 5 | 4 | 7/8 | 5 1/2 | 1 |
| 1 1/4 | 4 | 1/2 | 2 3/4 | 4 | 5/8 | 3 1/4 | 4 | 5/8 | 3 3/4 | 4 | 5/8 | 3 3/4 | 4 | 7/8 | 5 | 4 | 7/8 | 5 | 4 | 1 | 6 | 1 1/4 |
| 1 1/2 | 4 | 1/2 | 2 3/4 | 4 | 3/4 | 3 1/2 | 4 | 3/4 | 4 1/4 | 4 | 3/4 | 4 1/4 | 4 | 1 | 5 1/2 | 4 | 1 | 5 1/2 | 4 | 1 1/8 | 6 3/4 | 1 1/2 |
| 2 | 4 | 5/8 | 3 1/4 | 8 | 5/8 | 3 1/2 | 8 | 5/8 | 4 1/4 | 8 | 5/8 | 4 1/4 | 8 | 7/8 | 5 3/4 | 8 | 7/8 | 5 3/4 | 8 | 1 | 7 | 2 |
| 2 1/2 | 4 | 5/8 | 3 1/2 | 8 | 3/4 | 4 | 8 | 3/4 | 4 3/4 | 8 | 3/4 | 4 3/4 | 8 | 1 | 6 1/4 | 8 | 1 | 6 1/4 | 8 | 1 1/8 | 7 3/4 | 2 1/2 |
| 3 | 4 | 5/8 | 3 1/2 | 8 | 3/4 | 4 1/4 | 8 | 3/4 | 5 | 8 | 3/4 | 5 | 8 | 7/8 | 5 3/4 | 8 | 1 1/8 | 7 | 8 | 1 1/4 | 8 3/4 | 3 |
| 3 1/2 | 8 | 5/8 | 3 1/2 | 8 | 3/4 | 4 1/4 | 8 | 7/8 | 5 1/2 | 8 | 7/8 | 5 1/2 | – | – | – | – | – | – | – | – | – | 3 1/2 |
| 4 | 8 | 5/8 | 3 1/2 | 8 | 3/4 | 4 1/2 | 8 | 7/8 | 5 1/2 | 8 | 7/8 | 5 3/4 | 8 | 1 1/8 | 6 3/4 | 8 | 1 1/4 | 7 3/4 | 8 | 1 1/2 | 10 | 4 |
| 5 | 8 | 3/4 | 3 3/4 | 8 | 3/4 | 4 3/4 | 8 | 7/8 | 5 3/4 | 8 | 1 | 6 1/2 | 8 | 1 1/4 | 7 1/2 | 8 | 1 1/2 | 9 3/4 | 8 | 1 3/4 | 11 3/4 | 5 |
| 6 | 8 | 3/4 | 4 | 12 | 3/4 | 4 3/4 | 12 | 7/8 | 6 | 12 | 1 | 6 3/4 | 12 | 1 1/8 | 7 1/2 | 12 | 1 3/8 | 10 1/4 | 8 | 2 | 13 1/2 | 6 |
| 8 | 8 | 3/4 | 4 1/4 | 12 | 7/8 | 5 1/2 | 12 | 1 | 6 3/4 | 12 | 1 1/8 | 7 1/2 | 12 | 1 3/8 | 8 3/4 | 12 | 1 5/8 | 11 1/2 | 12 | 2 | 15 | 8 |
| 10 | 12 | 7/8 | 4 1/2 | 16 | 1 | 6 1/4 | 16 | 1 1/8 | 7 1/2 | 16 | 1 1/4 | 8 1/2 | 16 | 1 3/8 | 9 1/4 | 12 | 1 7/8 | 13 1/4 | 12 | 2 1/2 | 19 1/4 | 10 |
| 12 | 12 | 7/8 | 4 3/4 | 16 | 1 1/8 | 6 3/4 | 16 | 1 1/4 | 8 | 20 | 1 1/4 | 8 3/4 | 20 | 1 3/8 | 10 | 16 | 2 | 14 3/4 | 12 | 2 3/4 | 21 1/4 | 12 |
| 14 | 12 | 1 | 5 1/4 | 20 | 1 1/8 | 7 | 20 | 1 1/4 | 8 1/4 | 20 | 1 3/8 | 9 1/4 | 20 | 1 1/2 | 10 3/4 | 16 | 2 1/4 | 16 | – | – | – | 14 |
| 16 | 16 | 1 | 5 1/4 | 20 | 1 1/4 | 7 1/2 | 20 | 1 3/8 | 8 3/4 | 20 | 1 1/2 | 10 | 20 | 1 5/8 | 11 1/4 | 16 | 2 1/2 | 17 1/2 | – | – | – | 16 |
| 18 | 16 | 1 1/8 | 5 3/4 | 24 | 1 1/4 | 7 3/4 | 24 | 1 3/8 | 9 | 20 | 1 5/8 | 10 3/4 | 20 | 1 7/8 | 12 3/4 | 16 | 2 3/4 | 19 1/4 | – | – | – | 18 |
| 20 | 20 | 1 1/8 | 6 1/4 | 24 | 1 1/4 | 8 | 24 | 1 1/2 | 9 1/2 | 24 | 1 5/8 | 11 1/4 | 20 | 2 | 13 3/4 | 16 | 3 | 21 1/4 | – | – | – | 20 |
| 22 | 20 | 1 1/4 | 6 1/2 | 24 | 1 1/2 | 8 3/4 | 24 | 1 5/8 | 10 | 24 | 1 5/8 | 12 | – | – | – | – | – | – | – | – | – | 22 |
| 24 | 20 | 1 1/4 | 6 3/4 | 24 | 1 1/2 | 9 | 24 | 1 3/4 | 10 1/2 | 24 | 1 7/8 | 13 | 20 | 2 1/2 | 17 1/4 | 16 | 3 1/2 | 24 1/4 | – | – | – | 24 |