Abstract: This invention concerns an end-of-car hydraulic cushioning device for use on rail cars and a method of repairing such devices. The cushioning device has a piston and shaft assembly which is subject to train action forces. The piston and shaft are connected by means of a threaded engagement which prevents relative axial movements between the two parts. Rotational movement of the piston on the shaft is prevented by a hardened steel pin disposed in aligned, radial holes formed in the piston and shaft. The pin and holes are sized to provide clearance between the piston and pin. This permits piston metal deformation to occur during high speed impacts without catastrophically stressing the steel pin. A filler rod retains the pin in the radial holes.

Abstract: A method of repairing an end-of-car cushioning device for railroad cars is disclosed. The cushioning device is of the type having a piston and a shaft connected to the piston. In such devices, the shaft may become damaged with wear. In the disclosed method of repair, the old piston and shaft are removed from the cushioning device. The old shaft is substantially removed from the piston. The piston's true center is found, and a bore is cut through it. The bore is threaded, and an angled chamfer is cut in one end of the bore. A new shaft is provided with a threaded portion, the threads being adapted to mate with the threads of the bore. The shaft also has an angled chamfer adapted to mate with the bore's chamfer. The new shaft is connected to the old piston so that the threads engage and the chamfers abut.

Abstract: A method of repairing an end-of-car cushioning device for railroad cars is disclosed. The cushioning device is of the type having a piston and a shaft connected to the piston. In such devices, the shaft may become damaged with wear. In the disclosed method of repair, the old piston and shaft are removed from the cushioning device. The old shaft is substantially removed from the piston. The piston's true center is found, and a bore is cut through it. The bore is threaded, and an angled chamfer is cut in one end of the bore. A new shaft is provided with a threaded portion, the threads being adapted to mate with the threads of the bore. The shaft also has an angled chamfer adapted to mate with the bore's chamfer. The new shaft is connected to the old piston so that the threads engage and the chamfers abut.