- Clean the surface before trying to remove the broken stud.
- Flatten the broken end.
- Punch with centering punch at the centre of broken stud.
- Use a small drill to make a hole on the broken stud , ensure no damage to threads.
- Again drill a little bigger hole and ensure no damage to threads
- Use the stud extractor to remove the broken stud by rotating in anti clockwise direction
- Note-- stud extractor has a left handed thread. We can also remive the broken stud by using WD 40 and turning the stud with the help of screw driver or chiesel
Any opening in a pressure vessel is kept to a minimum and for a man entry an elliptical hole is lesser in size than the corresponding circular hole. More over it is prime concern to have a smoothed generous radius at the corners to eliminate stress concentration. Hence other geometrical shapes like rectangle and square are ruled out. To compensate for the loss of material in the shell due to opening, a doubler ring has to be provided around the opening. The thickness of the ring depends on the axis length along the dirrection in which the stresses are maximum and the thickness of the shell. It is important to align the minor axis along the length of the vessel, as the stress in this direction is maximum. Longitudinal stress: Pd/2t where P= pressure inside the vessel, d= diameter of the arc, t= thickness of the shell plating Circumferential stress: Pd/4t More over a considerable material and weight saving is achieved as minor is along the direction of maximum stress.