- Combined effect of reduced effectiveness of L.O and directional thrust of the con rod.
- This is maximum at around 45 degree ATDC Uneven loading of units and overloading
- Max Allowed: 1/4th of the bearing clearance
- Removed By: Insitu Grinding and polishing
- Reference: Fillet of crank web
- Max. Allowed Grinding: 2mm, because after grinding 2mm or more surface hardness reduces drastically. Due to this maximum allowable grinding is 2mm. Bottom bearing damage reason is the ovality, bearing clearance and condition of L.O supply
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.