Abstract: A rail grinding apparatus for railroad rails has a grinding belt wrapped around motor-driven pulleys which are rotatably mounted on a frame. The frame is supported on the surface of a rail by rollers which bear the weight of the grinding apparatus. A noise guard surrounds the grinding belt to reduce noise.

Abstract: A small-sized gas pressure welding machine for rails comprises a pressure application unit and an excess metal punching unit. The pressure application unit includes a positioning bed disposed along the rail feet of rails to be welded together, a movable pressure application clamp mechanism provided at one end of the positioning bed and a stationary pressure application clamp mechanism provided at the other end of the positioning bed. The movable clamp mechanism clamps the rail foot of one of the rails and provides an abutting pressure. The stationary clamp mechanism clamps the rail foot of the other rail and receives the abutting pressure.

Abstract: A gas pressure welding machine comprises a movable clamp means for clamping one of reinforcing rods to be joined together, a stationary clamp means for clamping the other reinforcing rod, a punching die for punching-shearing a bulge being formed around a joint portion of the reinforcing rods, and a key connection mechanism for detachably connecting the movable clamp means and the punching die, whereby the reinforcing rods are subjected to pressure butt welding to form a bulge around a joint portion thereof and the bulge is immediately punching-sheared under red heat by the punching die.

Abstract: A method of field welding head-hardened rails which includes the steps of gas pressure welding the rails, shearing off excess metal therefrom at the welded portion with a portable welder device, subjecting the railhead of the pressure welded portion of the rails to a subsequent heat treatment with a gas heater device, setting a width of the pressure welded portion to be heated at the time of the subsequent heat treatment with a pair of jigs, and cooling the portion which has undergone the subsequent heat treatment with an air blowing type cooler.

Abstract: A build-up spraying apparatus is disclosed which is capable of positionally adjusting the spreading rate of build-up metal powder on an article along the spreading direction to satisfactorily carry out partial or local build-up as well as uniform build-up as desired. The build-up spraying apparatus includes a fluid control device for spreading build-up metal powder having a pair of control gas injection nozzles formed at the both sides of the interior thereof and a control gas switching cycle setting means for supplying two systems of control gas to the fluid control device at a predetermined cycle to positionally control the spreading rate of build-up metal powder in the spreading direction. The apparatus also includes at least one heating burner body for heating build-up metal powder ejected from the fluid control device, the heating burner body being adapted to vary the amount of heat according to the difference in injection rate of build-up metal powder in the spreading direction.

Abstract: A punching-shearing method for inspecting the quality of a butt welded joint comprises pressure butt welding steel members under heat to form an annular bulge around the joint portion of the steel members, punching-shearing the bulge under red heat immediately after the pressure butt welding process from one side of the bulge in parallel with the axes of the steel members by use of a shearing die having higher and lower shearing edge portions so that the higher shearing edge portions penetrate the bulge prior to the lower shearing edge portions, so as to cause the base of the bulge to remain around the joint portion in a slightly higher position than the peripheral surfaces of the steel members, and determining the quality of the joint portion from the peripheral surface of the base of the bulge remaining on the joint portion.

Abstract: A butt welding and burr shearing machine for metal rod, e.g., reinforce steel has opposed relatively slidable clamping devices (8, 9), which has positioning clamp (10) and pivotable clamp lever to clamp the rod by lever action. One of the clamping devices mounts split type shear dies by the positioning clamp and the clamp lever respectively. In the cutting position of the shear dies 21, 22 the rod F2 is not clamped by the clamping device 10 on which the shear dies are mounted.By a series of simple operations the rods to be jointed are loaded sideways, clamped by rotating clamp lever, and pressure butt welded, and bulge formed by welding process is sheared off. The completed rod is removed sideways.