How do you tighten a 8 bolt flange?
- First time around just snug the nuts with a hand wrench.
- Second time around tighten the nuts firmly with the same wrench.
- Third time around apply approximately 25% recommended torque.
- Fourth time apply approximately 75% of recommended torque.
- Fifth time around, apply 100% of recommended torque.
How do I determine bolt torque for flange connections?
The minimum required bolt load divided by the number of bolts in the flange will determine the minimum f, or force, needed to use the torque equation. After calculating the torque, ensure the bolts are not over-stretching and exceeding their yield strength, or some predetermined design stress.
How do you torque a flange bolt?
First to half torque and second to final torque.
- Put the socket on the head of the wrench.
- Turn the nut by hand until it catches the screw threading.
- Turn the handle clockwise to tighten the nut.
- Stop turning the wrench when it stops clicking or moving.
What is the correct order for tightening bolts on a flange?
Tightening sequence The first pass, lightly tighten the first bolt then move directly across or 180 degrees for the second bolt, then move1/4 turn around the circle or 90 degrees for the third bolt and directly across for the fourth. Continue this sequence until all bolts are tightened.
How do you tighten a 12 flange bolt?
How much torque does a bolt need?
US Recommended Bolt Torque
| Size | Recommended Torque | |
|---|---|---|
| Grade 2 | 18-8 S/S | |
| 7/16″ | 24 | 33 |
| 1/2″ | 37 | 45 |
| 9/16″ | 53 | 63 |
When to use hydraulic torque on a flange?
When the bolt loading requires a torque higher than 678 Nm (500 ft-lbs.) to be applied, hydraulic bolt torqueing is recommended.
When to use Torquing on a flange bolt?
When the bolt loading requires a torque higher than 678 Nm (500 ft-lbs.) to be applied, hydraulic bolt torquing is recommended.
What should be used to tighten flange bolts?
The bolts shall be tightened by torque control, using the Anti-seize lubricant shall be used such as Molykote or equivalent, before installation. The specified method of bolt tightening is equally applicable to coated, galvanized and ungalvanized bolts.
How is torque calculated on a gasket test?
Torque is based the higher of 40% of bolt yield, T3 or 4800 psi gasket stress up to either the maximum allowable material stress or a maximum bolt yield of 60%. The above was calculated using the proposed ASME Gasket Constants (ROTT Testing, Ecole Polytechnique) for each material.