Abstract: The invention relates to an apparatus for coating the inner surface of a tunnel section with sprayed concrete, comprising a spray lance b) (4) and a spray nozzle a) (7) which can each be moved in all directions by means of joints, a first control device k) for the operation of the spray lance b) (4) and a second control device l) for the operation of the spray nozzle a) (7) being provided.

Abstract: A device for applying sprayed concrete to surfaces during tunnel construction and mining. The device includes a radar system including at least one radar sensor that is arranged on a circumference around a spray nozzle. A method for determining at least one parameter that determines the application of sprayed concrete to surfaces during tunnel construction and mining.

Abstract: The invention relates to an apparatus for coating the inner surface of a tunnel section with sprayed concrete, comprising a spray lance b) (4) and a spray nozzle a) (7) which can each be moved in all directions by means of joints, a first control device k) for the operation of the spray lance b) (4) and a second control device l) for the operation of the spray nozzle a) (7) being provided.

Abstract: A spray nozzle of the type adapted to feed a liquid to a material being sprayed therefrom comprises a tubular spray conduit around which is arranged an annular feed port, this feed port being closed in a liquid-tight manner by resilient material openable by liquid pressure and whose degree of opening, and therefore the quantity of liquid fed to the material, rises linearly with increasing liquid pressure. Preferably, the resilient material is provided by a membrane ring (7) which is a flat ring with inwardly-tapering radial ridges (8b) raised thereon, the gaps between the ridges being filled with an elastomeric material, such that a series of resilient segments (9) is created. Under liquid pressure, the segments are compressed equally, giving a nearly completely annular flow of liquid into the material. The nozzle is particularly useful for the spraying of concrete, especially by the dry method.

Abstract: A mobile shortcrete spraying apparatus has a spraying device which comprises a support arm able to move horizontally and vertically, a spray lance likewise movable, supported thereon, and at the end of the lance and rotatable with respect to the longitudinal axis of the lance a spray nozzle and a measuring probe. The measuring probe determines distance of the probe from a multiplicity of measuring points on a substrate to be sprayed, according to a predetermined grid pattern, and a control unit causes the spray nozzle to spray perpendicularly with respect to a plane defined by three such measuring points or a line defined by two measuring points.

Abstract: A pumping apparatus of the type comprising twin cylindrical pumping chambers which alternately take in and deliver material to be pumped, the taking in being via ports in a common feeding chamber and the delivery being via a delivery conduit which moves to the port of the chamber which is to deliver. The pumping is carried out by hydraulically-actuated pumping pistons in the chambers, the hydraulic circuitry being adapted to ensure that the pumping piston in that chamber taking in material arrives at the fully charged position before the delivering chamber attains the fully discharged position. In another embodiment, the pumping apparatus comprises a "push-over" facility, wherein the speed of the pumping is automatically increased to compensate for the drop in flow rate caused by the time taken by the delivery conduit to move from one port to the other. The apparatus gives an exceptionally pulsation-free flow and is especially useful in concrete spraying apparatus.

Abstract: A shotcrete gun having a rotatable multichamber rotor, with a top feed hopper for receiving a dry concrete mixture in a chamber, and a bottom outlet pipe for discharging the dry concrete mixture from the chamber. The outlet pipe having a compressed air connector for connection to a compressed air source. The upper surface of the drum rotor adjoins a gasket having one or more openings fixed to a clamping plate. The lower surface of the drum rotor adjoins a gasket which is fixed to a base plate. The hopper and the outlet pipe being spaced such that a chamber which communicates directly with the hopper can be moved so that it no longer communicates with the hopper but communicates with the outlet pipe. The clamping plate has a compressed air connector for blowing the dry mixture out into the outlet pipe.

Abstract: A shotcrete gun having a rotatable multichamber rotor, with a top feed hopper for receiving a dry concrete mixture in a chamber, and a bottom outlet pipe for discharging the dry concret mixture from the chamber. The outlet pipe having a compressed air connector for connection to a compressed air source. The upper surface of the drum rotor adjoins a gasket having one or more openings fixed to a clamping plate. The lower surface of the drum rotor adjoins a gasket which is fixed to a base plate. The hopper and the outlet pipe being spaced such that a chamber which communicates directly with the hopper can be moved so that it no longer communicates with the hopper but communicates with the outlet pipe. The clamping plate has a compressed air connector for blowing the dry mixture out into the outlet pipe, and at least three pressure cylinders in order to press the gasket against the drum rotor. Means are provided for maintaining the pressure in the cylinders proportional to the pressure in the outlet pipe.