Abstract: An improved pick and pick holder assembly for use in mineral winning and the like. The improved pick and pick holder increases the effective life of a tool and pick holder by minimizing the shifting of the pick within the pick holder. The movement of the pick is minimized by front and rear bearing surfaces that remain positively engaged with front and rear bearing surfaces of the pick holder for loads applied to the pick that are predominantly inward and predominantly rearward.

Abstract: A cutter tool that includes a shank by which the tool is releasably retainable within a tool holder, an enlarged shoulder or heel provided at one end of the shank and adapted, in use, to abut a seating surface of a tool holder and limit the penetration of the tool holder into a receiving aperture of the tool holder, and an integral blade provided beyond the enlarged shoulder or heel and terminating in a carbide or other tip. The tool is provided with a zone of weakness such that if subjected to fracture forces, a fracture will be encouraged to propagate from the zone of weakness in a particular desired manner.

Abstract: A cutter tool that includes a shank by which the tool is releasably retainable within a tool holder, an enlarged shoulder or heel provided at one end of the shank and adapted, in use, to abut a seating surface of a tool holder and limit the penetration of the tool holder into a receiving aperture of the tool holder, and an integral blade provided beyond the enlarged shoulder or heel and terminating in a carbide or other tip. The tool is provided with a zone of weakness such that if subjected to fracture forces, a fracture will be encouraged to propagate from the zone of weakness in a particular desired manner.

Abstract: An improved pick and pick holder assembly for use in mineral winning and the like. The improved pick and pick holder increases the effective life of a tool and pick holder by minimizing the shifting of the pick within the pick holder. The movement of the pick is minimized by front and rear bearing surfaces that remain positively engaged with front and rear bearing surfaces of the pick holder for loads applied to the pick that are predominantly inward and predominantly rearward.

Abstract: A chain link (1) of steel has two spaced-apart transverse apertures (2) to receive portions of leading and trailing pivot pins (4) and, on an upper surface, a seat (6, 7) to receive a welded-in pick box (8), the link (1), at one side at least, being provided with at least one pad (14) of a material of higher wear resistance than the steel of the link (1). The invention also includes a steel pivot pin (4) for use in connecting together, in an articulated manner, steel links (1) of mineral cutter/removal chain, at least one end of the pin (4) being provided with a wear pad (16). The invention also includes a mineral cutting/removal chain for use with an inclined jib, constructed from an odd number of links (1) articulated on pins (4).

Abstract: A rotary cutting head (1) for a mineral mining machine, comprises a drive shaft (5) carrying a central drum (4), and beyond each end of the central drum (4), an outer drum (2,3), each drum being provided with an array of pick boxes (7) to receive an individual pick (8), wherein the drive shaft (5) has a longitudinal bore (10) housing at least one water conveying tube (11), which together with a network of bores (25) enable a single water admission cartridge interposed between an outer end of one of the drums (2), and an end face plate (16) of that drum (2) to supply water to all three drums (2, 3, 4).

Abstract: A rotary cutting head (1) for a mineral mining machine, comprises a drive shaft (5) carrying a central drum (4), and beyond each end of the central drum (4), an outer drum (2,3), each drum being provided with an array of pick boxes (7) to receive an individual pick (8), wherein the drive shaft (5) has a longitudinal bore (10) housing at least one water conveying tube (11), which together with a network of bores (25) enable a single water admission cartridge interposed between an outer end of one of the drums (2), and an end face plate (16) of that drum (2) to supply water to all three drums (2, 3, 4).

Abstract: A “wet” pick box 1 comprises a body member 2, adapted in use to be welded to a rotary cutting head, whilst an aperture 5 is provided in the body member. Bores 15, 16 in the body member define an internal water course 6 connectable, at an inlet end 7, to a source of pressurised water, an aperture 8 in the body member is adapted to house a water discharge nozzle and is connected to an outlet end 9 of the watercourse 6. A tapped hole 10 intersects the bores 15 and 16 and a member 11A or 11B is insertable into, and removable from, the hole 10. A rotary mineral cutting head can be provided to which a plurality of such pick boxes are welded.

Abstract: A pick box (1) of a tooling system for mineral winning etc., has an elongated aperture (4) to receive, in use, a removable liner sleeve (6) of the tooling system, the box (1) providing a seating surface (7) extending orthogonally with respect to the axis (5) of the aperture (4). The external periphery of the sleeve (6) and the internal periphery (8) of the box aperture (4) are so profiled, e.g. hexagonally, as to prevent relative rotation and the internal periphery of the box aperture is interrupted at (11) to provide at least one surface for engagement, in use, with a retainer device (12) of an inserted sleeve (6), whilst the sleeve has an external groove (22) to receive a retainer device (12). The invention also includes a sleeve (6) having an enlarged head (16), a longitudinal circular bore (26), and a circumferential groove (22) fitted with a retainer ring (12). The invention further includes a box (1) and a sleeve (6) in combination, and a drum (3).

Abstract: A hydraulic circuit includes a fluid pressure inlet line (1); a fluid pressure delivery line (2); and a filter unit (FU) interposed between the inlet line (1) and the delivery line (2), with the circuit incorporating an automatic back flushing facility. The latter comprises a valve arrangement A, B, C, D, capable of temporarily preventing initial flow of fluid through the filter unit (FU) in a delivery direction, causing reverse fluid flow through the filter unit (FU) in a back flushing direction, for a predetermined period, with the flushing sequence initiated by the valve arrangement sensing a flow of fluid, at a predetermined pressure, and after the predetermined period, causing fluid flow in the normal delivery direction.