Machine Design
A plate with an elliptical hole in the centre, with semi-major axis (a) perpendicular to the direction of loading and semi-minor axis (b) along the direction of loading, is subjected to a pull P. The maximum stress induced at the edge of the hole is equal to (where σ = Stress for a plate with no hole i.e. nominal stress)
A slot is cut partly in middle of nut and then slot reduced by tightening a screw
One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming
A hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip
Through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter spitted and bent in reverse direction at other end
EXAMIANS