How do I choose bolts for flange?
The quantity of bolts for a flange connection will be given by the number of bolt holes in a flange, diameter and length of bolts is dependent of flange type and Pressure Class of flange. Stud Bolt length are defined in ASME B16. 5 standard.
What grade are flange bolts?
The most common materials for stud bolts (for flanges) are ASTM A193 (grade B7, B8, B8M, B8T), ASTM A453 (grade 660), ASTM A320 (grade L7, L7M), and ASTM A182 (duplex and super duplex bolting).
How many bolt holes are in a 3 300 flange?
8
ANSI/ASME B16. 5 Class 300 Forged Flanges Add Flanges
| Nominal Size | Outside Diameter (OD) | No. of Bolt Holes |
|---|---|---|
| 3 | 8.25 | 8 |
| 31⁄2 | 9.00 | 8 |
| 4 | 10.00 | 8 |
| 5 | 11.00 | 8 |
What is the bolt circle diameter on a flange?
The Bolt Circle is the measurement (diameter) of an imaginary circle passing through the centers of all the bolts in a round pattern. This is represented by the Blue Dashed Circle in the drawing. To measure such circle measure from the center of one bolt directly across to the center of the other bolt.
What does flange mean on a bolt?
Flange bolts have a circular flange under the head that acts like a washer to distribute the load. Flange bolts that are non-serrated are sometimes called frame bolts.
How do I choose the right bolt?
This is how you choose the right bolt for the joint:
- First, identify the load case.
- Determine the necessary clamping force in the joint.
- Choose the smallest bolt diameter that can support the clamp load.
- Choose an effective bolt securing method.
- Decide on the most appropriate tightening method.
Does bolt length matter?
Does length really matter? The length of a bolt and the number of threads has a bearing on proper tension. Most stretching occurs in the threaded portion of the bolt. Automotive engineers size bolts, to provide adequate stretch and substituting a different length can cause problems.
Can I use a bolt and washer instead of a flange bolt?
The effect of using washers instead of flanged nuts and bolts is to increase the number of interfaces within the joint. Since each face will sustain an embedding loss, the net effect of using washers is to increase the loss of bolt tension due to this effect.