Low-cost method of making cracked connecting rods comprised of forged

Abstract

Method of making exactly remateable cracked connecting rods comprised of forged wrought steel possessing typical ductility, said rods having a big end with a big bore therein and an arm-like body extending therefrom with a small end at its extremity, the big end having crack initiating crevices formed therein to promote a cracking plane, comprising the following steps: (a) placing the big bore of an uncracked connecting rod onto a nestable separable pair of cantilevered hemispherical blocks complementary to the internal shape of the big bore; (b) continuously and uniformly separating the cantilevers of said blocks to initially assure contact of said blocks with the rod at a tangent point aligned substantially on the longitudinal axis of the uncracked connecting rod, and thereafter to exert sufficient force through said cantilevers to the blocks to pull apart the connecting rod at the cracking plane determined by said crack initiating crevices, the connecting rod cap and body being free to experience small but independent macro-rotation relative to the connecting rod axis during such cracking separation.