A lockbolt for installation into apertured workpiece members, comprising a pin having a head and a tail end provided with locking grooves and a single pull groove, wherein an installation tool having a collet with a corresponding shape to the pull groove is used to apply an increasing pulling force to the pin tail, thereby to push the collet towards the workpiece, and as the force applied by the hydraulic piston further increases, causing the collar to be swaged into the lock grooves, and halting the force applied by the tool either at a predetermined maximum value or when the pin tail breaks at a breaker groove formed by the single pull groove.

A lockbolt for installation into apertured workpiece members, comprising a pin having a head and a tail end provided with locking grooves and a single pull groove, wherein an installation tool having a collet with a corresponding shape to the pull groove is used to apply an increasing pulling force to the pin tail, thereby to push the collet towards the workpiece, and as the force applied by the hydraulic piston further increases, causing the collar to be swaged into the lock grooves, and halting the force applied by the tool either at a predetermined maximum value or when the pin tail breaks at a breaker groove formed by the single pull groove.

An annular reference surface is formed around a through-hole of an eye portion. A distal-end-side curved portion is formed at a first corner portion, on an outer side of the annular reference surface. The thickness of the distal-end-side curved portion is reduced in a range of a length from the first flat surface toward the distal end surface. A hole-side curved portion whose thickness is reduced toward an inner surface of the through-hole is formed at a second corner portion, on an inner side of the annular reference surface. The length of the hole-side curved portion is less than the length of the distal-end-side curved portion. The hole-side curved portion is curved with a greater curvature than that of the distal-end-side curved portion.

An improved forging process includes the steps of pre-heating the top and bottom dies of a forging press to a specified temperature, and maintaining both dies at the specified temperature during subsequent forging operation with closed-loop temperature control systems. The top and bottom forging dies are each coupled to a dedicated thermic fluid heater, the temperature of each die is individually measured and compared to a respective target temperature, and the respective thermic fluid heaters are controlled in relation to detected deviations of the measured temperatures from the target temperatures. Compressor wheel preforms produced according to this process consistently exhibit primarily radial grain orientations that exactly match the expected values.

An improved forging process includes the steps of pre-heating the top and bottom dies of a forging press to a specified temperature, and maintaining both dies at the specified temperature during subsequent forging operation with closed-loop temperature control systems. The top and bottom forging dies are each coupled to a dedicated thermic fluid heater, the temperature of each die is individually measured and compared to a respective target temperature, and the respective thermic fluid heaters are controlled in relation to detected deviations of the measured temperatures from the target temperatures. Compressor wheel preforms produced according to this process consistently exhibit primarily radial grain orientations that exactly match the expected values.

A part of kinetic energy during lowering of a slide of a press machine is converted into oil hydraulic energy by a first oil hydraulic cylinder, and the converted oil hydraulic energy (hydraulic oil having boosted first system pressure) is stored in a first accumulator. The hydraulic oil having the first system pressure stored in the first accumulator is discharged in knockout process, a second oil hydraulic cylinder that functions as a knockout cylinder is raised to perform knockout operation of a product worked by the press machine. Consequently, it is possible to perform knockout operation without using a dedicated driving source such as an oil pressure source and an air pressure source, and provide a low-cost hydraulic knockout device.

A part of kinetic energy during lowering of a slide of a press machine is converted into oil hydraulic energy by a first oil hydraulic cylinder, and the converted oil hydraulic energy (hydraulic oil having boosted first system pressure) is stored in a first accumulator. The hydraulic oil having the first system pressure stored in the first accumulator is discharged in knockout process, a second oil hydraulic cylinder that functions as a knockout cylinder is raised to perform knockout operation of a product worked by the press machine. Consequently, it is possible to perform knockout operation without using a dedicated driving source such as an oil pressure source and an air pressure source, and provide a low-cost hydraulic knockout device.

A hydraulic machine unit that can be operated with various working forces, in which working medium is selectively delivered, via a pump-piston accumulator system, to a main cylinder and at least one driving cylinder, wherein at least for one working stroke a pump system of the pump-piston accumulator system is used to provide working medium to a piston accumulator of the pump-piston accumulator system, and then at least for the working stroke at least the main cylinder is charged with a working pressure from the piston accumulator, and wherein at least for a return stroke the at least one driving cylinder is charged with a return stroke pressure from the pump-piston accumulator system, can be of structurally simple configuration if, at reduced working forces, the working pressure is reduced with respect to the piston accumulator pressure prevailing in the piston accumulator.

A hydraulic machine unit that can be operated with various working forces, in which working medium is selectively delivered, via a pump-piston accumulator system, to a main cylinder and at least one driving cylinder, wherein at least for one working stroke a pump system of the pump-piston accumulator system is used to provide working medium to a piston accumulator of the pump-piston accumulator system, and then at least for the working stroke at least the main cylinder is charged with a working pressure from the piston accumulator, and wherein at least for a return stroke the at least one driving cylinder is charged with a return stroke pressure from the pump-piston accumulator system, can be of structurally simple configuration if, at reduced working forces, the working pressure is reduced with respect to the piston accumulator pressure prevailing in the piston accumulator.

The present invention relates, in particular, to a forging hammer comprising a striker and a hydraulic linear drive that is coupled to the striker and is designed to drive the striker, which drive comprises a hydraulic circuit having a servo-motor hydro pump, a hydraulic cylinder, in particular a differential cylinder, which is fluidically connected downstream of the hydro pump via a directional valve module, and a servo-motor hydro generator, which is fluidically connected downstream of the hydraulic cylinder via the directional valve module, and comprising in addition a control unit configured at least for the simultaneous control of the hydro pump, the hydro generator and the directional valve module.