Abstract: A gyratory crusher having a frame (1) and in the frame an eccentric shaft (3) rotatable around a vertical shaft in the frame, with a vertical inclined hole in it. A main shaft (4) is supported by bearings in the hold of the eccentric shaft, a supporting cone (5) being attached to the upper end of said main shaft (4). Around the main shaft, below the supporting cone (5) there is a sealing cover (10) covering the eccentric shaft. The upper edge (12) of the sealing cover (10) is sealed against the main shaft (4) by means of a sealing member (13), the outer edge of which has been fitted in an annular groove (17) on the inner edge (12) of the sealing cover (10). The face-to-face arranged upper and lower surfaces so the part (13") of the sealing member (13) in the groove and the groove (17) of the sealing cover (10) are inclined so that their outer edges are higher up than their inner edges.

Abstract: The application presents an adjustable cone crusher which has a hydraulic cylinder-plunger-combination (15, 4) for adjusting the setting and supporting a main shaft at its bottom end. The combination contains a bypass channel (21), through which the pressure medium escapes from the cylinder when the combination has been extended by a certain distance. In this way the crushing cone is prevented from rising too much upwards.

Abstract: A hydraulic control system for a gyratory crusher has a hydraulically supported main shaft. An inlet line to the cylinder is provided with a pressure relief valve. When the pressure in the cylinder, e.g. because of a disturbance, exceeds the opening pressure of the relief valve, fluid flows from the cylinder through the pressure relief valve to the lubricating circuit of the crusher and further to the return line. The safety system of the crusher is simple, reliable, and quick.

Abstract: The invention relates to a conveyor system, which has several conveyors (3/4) joined to together into a chain. There is an articulation (9) at the joining point of the conveyors, which allows the conveyors to turn relative to each other. The chain may be formed and disassembled rapidly. The system is applicable to be used e.g. at mines.

Abstract: A wear resisting steel of the Hadfield-type and method for its production are provided. This iron base alloy contains in its basic composition following alloying carbon, manganese, silicon and optionally chromium, and/or molybdenum, and/or tungsten. The matrix of the steel is formed by the ductile austenite. Carbides appear on the grain boundaries in the form of roundish, hard, separate precipitates. In the grain boundary zone and inside the grains are hard, needle-shaped nitride and carbonitrides to improve the wear resistance especially against abrasive wear. In accordance with the method the steel is solution heat treated at a temperature range below 1100.degree. C. (e.g., 950.degree. to below 1100.degree. C.) so that carbide, nitride and carbonitride precipitates formed in the microstructure following casting are partially but not completely dissolved.

Abstract: The invention relates to a gyratory crusher in which a piston surrounds a wabbler shaft or eccentric sleeve and the radial forces of the spindle shaft are transmitted to the frame of the crusher through the piston.