Based on the geometrical relation between tappets and cams, uniform formulas for mutual lift-range transition between flat based tappet, roller (or sphere) tappet and cone tappet were presented.

Stresses in cone cylinder shells with toroidal transition inserted are investigated by an analytical method, and buckling pressures for the shells are presented by Rayleigh Ritzs method.

The transition -cone is a heavy component with strong stiffness, large -quantity of welding and heavy weight. The control of its welding deformations is a puzzle.