OPENING REINFORCING APPARATUS Russian patent published in 1994 - IPC

FIELD: reinforcing of openings, for example openings for receiving bolts, by surface plastic deformation method. SUBSTANCE: reinforcement of opening edges is effectuated simultaneously from both sides by means of two punches, which have central through holes and one common induction-dynamic drive formed as flat current coil, copper disk fixed on one punch and preliminarily charged energy storage accumulator. Punch and current coil are mounted on common rod, which is inserted into opening to be reinforced. One punch carrying copper disk is slide fitted onto rod. This punch is positioned on rod so that copper disk is disposed in the vicinity of current coil. Other punch disposed at opposite side of opening to be reinforced is rigidly fixed on rod by means of threaded fastener. EFFECT: increased efficiency and enhanced reliability in operation. 2 dwg