Abstract: An extendable, retractable, erectable arm assembly for housing and supporting a water conduit extending outward from a tool located in a borehole, to a nozzle to produce a high pressure water cutting jet is provided. The arm assembly includes a plurality of interlocking arm segments for housing, supporting and moving the conduit through an angle of about 90.degree. from a stowed position to an operating position. The arm segments include integral, separable hinges capable of being interlocked such that pivotable movement is possible along any side thereof. These segments have mating apertures therethrough to accommodate the conduit. The assembly also includes an erecting device which provides compression on the segments and which gives the arm rigidity during movements. An alignment device is also included which keeps the segments aligned when the arm is deflected.

Abstract: A method for remotely monitoring conditions such as carbon monoxide or methane gas concentration, longwall roof support pressure, machine parameters or uncut coal, trona or potash layer thickness in a natural resource mining system such as a longwall or continuous mine system. The method utilizes a plurality of sensors connected to low magnetic moment transmitters, e.g. 0.1 ATM.sup.2, or high magnetic moment transmitters, e.g. 2.5 ATMhu 2, that transmit colleted data during multiple short burst transmission periods. Prior to transmission, the data is converted to a digital word format. An algorithm in the transmitter microcomputer ensures that random time intervals exist between data transmission bursts thus preventing a data transmission clash at the central receiver. A microcomputer algorithm in the central receiver protects against data contention caused by simultaneous transmission from several sensors.

Abstract: A process for automatic ploughing during the winning of coal and the like in a longwall working with a hydraulic advancing lining with individual support units controlled by an electro-hydraulic control means. A plough guide is shifted automatically in stages by the plough cutting depth after passage of the plough by means of rams allocated to the support units and the support units are automatically shifted up as a function of the plough movement. The support units are positioned in support groups of which a plurality in each case are offset relative to one another in the shifting direction by the plough cutting depth and/or a multiple thereof. During the ploughing run only those support units of which the residual stroke of the shifting rams still available for shifting the plough guide is smaller than the plough cutting depth are automatically re-located in each case at a distance behind the passing plough.

Abstract: A method of working metalliferous deposits which includes tapping a pay zone by development boreholes, hydraulically mining for a mineral in the pay zone through the formation of brine having a level which is maintained below the location of hydraulic mining of the mineral, shaping a working chamber by shifting the location of hydraulic mining along the axis of the borehole within the confines of the pay zone and lifting the brine out of the working chamber to the surface. The hydraulic mining of the mineral is alternated with the lift-of brine to the surface, such that the location of hydraulic mining is shifted from the floor of the pay zone to the roof of the pay zone at a speed which is not less than the speed at which the level of brine is rising in the working chamber. The method also includes tapping a pair of boreholes and forming working chambers in each.

Abstract: A manifold for a borehole miner, wherein the manifold is rigidly secured to a first and a second pipe of a pipe bundle; movably connected to at least one other pipe; and provided with a collimating nozzle unit associated with a deflector plate unit, such that a pressurized abrasive jet spray can be directed against the walls of a bore hole, and the back splash from the jet spray will be prevented from adversely affecting the pipes in the pipe bundle by the deflector plate unit.

Abstract: A process is provided for separation of an asbestos-containing material from a surface to which the asbestos-containing material is adhered, while preventing floating of dust of the removed asbestos-containing material, the process requiring jetting of pressurized water from a plurality of nozzles to the surface at a pressure of at least 80 kg/cm.sup.2 so as to wet and remove the asbestos-containing material therefrom by the energy possessed by the pressurized water.

Abstract: A method of downhole hydraulicking mineral resources includes production panels being laid out at a deposit, holes being sunk in a longitudinal axis of each production panel, and device for hydraulicking mineral resources, comprising a monitor and a means of lifting pulp to the surface, being lowered into each of the holes. A mineral is broken hydraulically by a jet from the monitor, and the monitor jet being displaced at least once in a horizontal plane within confines of a main sector extending in a direction opposite to that in which a next hole is located, in radial working so that pillars are formed therebetween. An angle of each radial working is about the divergence angle of the jet of the monitor, and the angle the radial working make with each other is decided by the conditions of stability of the pillars between the radial workings during a period of driving a radial working.

Abstract: An excavation apparatus includes a suction system with a suction tank pneumatically connected to a blower through a filter subassembly. A suction hose is pneumatically connected to the suction tank. A liquid jet system includes a liquid reservoir fluidically connected to a liquid pump, which in turn is fluidically connected to a spray wand. The suction and liquid jet systems are mounted on a vehicle. An excavation method includes the steps of dislodging earthen material with a liquid jet from the spray wand and sucking it into the suction tank with the suction system.

Abstract: A bucket wheel assembly for excavating solid material from the ground which can be slurried with water has a series of buckets mounted on a framework rotatable about a substantially horizontal axis, the buckets, being secured to the framework at spaced positions around the periphery, and each bucket having a leading edge portion engagable with the ground as the framework rotates to cause material to be scooped from the ground into the bucket. Sets of nozzles are mounted around the framework, each set of nozzles being located between an adjacent pair of buckets and spaced in the direction of movement of the buckets from the leading edge portion of a following bucket. A rotary valve is connected to the nozzles and to a source of liquid under pressure.

Abstract: In a mineral mining machine of the shearer drum cutter loader type, a system for supplying water at the required pressures includes an intensifier to which in use mine supply water is fed, the pressure being enhanced in the high pressure chambers and the high pressure water being fed to jets on the end of the cutting drum. Water exhausting from the low pressure chambers is fed to the dust and frictional sparking suppression sprays arrayed along the surface of the cutting drum. The method of the invention consists of generating in a simple and effective manner the requisite water pressures utilizing an existing main supply.

Abstract: A hydraulic borehole mining system has a cutting jet nozzle supported on an insert short length of tubing of a cutting jet head within a water supply conduit in the lowest section of a multi-conduit pipe string that extends from the surface through a borehole to a target zone to be mined. A rod extending from the surface through the string outside of the water supply conduit connects to the head to reposition the nozzle vertically, independent of movement of the conduit or string. The borehole annulus is sealed and connected to a surface standpipe for development of a hydrostatic head pressure that acts, with or without downhole pump assistance, to raise the slurry created by the nozzle jet up through a second conduit in the pipe string. Material is pumped down the same second conduit after mining to backfill the hole.

Abstract: The method of downhole hydraulicking of mineral resources consists in sinking main holes, fitting the main holes with casings down to a depth below a lower boundary of a pay-out bed, installing an apparatus for hydraulicking mineral resources in each main hole, breaking rock and forming cavities in a bedrock by a jet from a monitor provided in the apparatus for hydraulicking mineral resources. Auxiliary holes are sunk each above a face of each cavity, using a drilling tool, down to the cavity so that the mineral enters the cavity from the auxiliary hole as soon as the drilling tool is withdrawn therefrom. Pulp is lifted to the surface through the main holes until overburden rock is identified in the pulp.

Abstract: A cutter pick for a mining machine has a lug carrying a cutting tip of hard, abrasion resistant material at its forward end. A passage extends through the lug with provision at its rearward end for connection to a source of high pressure liquid and with a nozzle at its leading end venting through the cutting tip. The intention is that high pressure liquid issueing from the nozzle will degrade the rock before it is attacked by the cutting tip.

Abstract: Coal is mined using water jets to a remove a layer of thin horizontal slices of coal. The thickness of the layer is sufficiently small that elastic deformation of the roof of the layer due to settling will cause the roof to rest against the floor of the layer. A number of additional layers of slices are then extracted in the same manner, each immediately below the floor of the preceding layer. The thickness and location of these layers wiht respect to previous layers is such that elastic deformation of the roof of the first layer due to settling will cause the roof to rest against the floor of the last layer of slices. Through the sequential mining of layers in this manner from top to bottom, the entire seam of coal is extracted and the mine roof rests upon the mine floor without the need for artificial roof support.

Abstract: Discrete volumes, or slugs, of liquid are accelerated to high velocities utilizing energy stored by compressing the liquid. Liquid is forced into a pressure vessel already filled with liquid to effect the compression. A slug of liquid is ejected from the pressure vessel into a cumulation nozzle by the energy stored in the compressed liquid when a valve is rapidly opened. The valve is unseated when an unseating force exceeds a closing bias. The valve is then opened rapidly by an opening force generated by the compressed liquid. By repetitively introducing highly pressurized liquid into the pressure vessel, the valve automatically cycles to generate a series of pulsed liquid jets. Rapid opening of the valve is aided by an extension on the valve member which sealingly slides inside the passage of the cumulation nozzle to block release of liquid until the valve member accelerates sufficiently that the required opening rate is achieved as the extension clears the nozzle passage.

Abstract: Material, such as old unsound concrete material, is removed from a work surface by discharging water against such work surface at a pressure of from about 10,000 to about 25,000 psi from a rotating nozzle. During operation, the nozzle traverses the work surface along a series of linear paths and is incrementally moved in a longitudinal direction so as to pass over the work surface in a sequence of preferably overlapping transverse bands. An apparatus for carrying out the method of the invention comprises a support structure usefully in the form of a vehicle having an extendible arm driven by an extension means for incremental movement of that arm in a longitudinal direction. A rotatable nozzle is mounted on a nozzle support in turn secured to the extendible arm for bidirectional movement of the nozzle along a transverse linear path. Casters are also provided for maintaining the nozzle at a predetermined spacing from the work surface during operation of the apparatus.

Abstract: Operating head assembly, e.g. cutter head of a coal or other mining machine having provision for feeding a supply of water or other fluid to the head during operation has provision for phasing the fluid delivery to limit it to the zone about the head in which the cutting action is taking place dependent on the direction of movement of the head. Delivery jets of the head are fed through individual valve units (22) each having an independently operable hydraulic or other actuator (28), the power input thereto being controlled by apertured timing faces (36, 38) on co-acting parts of the head (11) and body (10), power feed through the timing faces being controlled e.g. in correspondence to the position of change-over valve (44, 46) operating in response to controls which direct movement of the head. In an alternative construction the valve units are actuated mechanically by a camming formation which can be indexed depending on the direction of movement.

Abstract: A gearbox for a rotary, mineral cutting head, comprises a casing housing speed reduction gearing and also a portion of a drive shaft supported by first and second, spaced-apart bearings, with at least one radially extending cylinder having a closed inner end and an open, outer end provided in said drive shaft and a reciprocable piston partially housed in said cylinder with a fluid seal between said piston and said cylinder; a variable volume, pressure-generating chamber defined between a radially inner end of said piston and a closed, inner end of its cylinder; a ring surrounding said drive shaft and having an inner profile and with a radially outer end of said piston in contact with said inner profile and with said piston.

Abstract: An integrated cutterhead for water jet assisted cutting which can be retrofitted to an existing machine by replacing its cutterhead. The pressure of the water supplied is intensified inside the cutterhead itself up to the level required for jet assist cutting by an even number of independent cylinders mounted inside the rotating drum, parallel to its axis. Each cylinder is afferent to one sector of the cutterhead. A stationary cam controlling the cylinders stroke can be adjustably rotated to adapt the distribution of high pressure water to the direction of the cutting operations. The cam is designed preferably as to make the water pressure of the jet correspond to the cutting depth of the cutting tool. This arrangement limits the high pressure water area to the drum of the cutterhead and does not require high pressure valves and distributors.

Abstract: A system for removal of workpiece material with a high velocity jet of working fluid, comprising an ultra-high pressure pump including a plurality of low pressure fluid cylinders and a plurality of high pressure cylinders longitudinally aligned with and adjacent the outer end of each low pressure fluid cylinder and having a high pressure piston reciprocally mounted therein and interconnected to reciprocate with a low pressure piston in an adjacent low pressure cylinder. High pressure valves are provided for each high pressure cylinder including an inlet check valve and an outlet check valve for releasing said working fluid under high pressure. A high pressure manifold is interconnected to the outlet check valves and a conduit carries the high pressure working fluid to a high velocity jet forming nozzle.

Abstract: Apparatus for removing structural concrete comprises an elongated hood having an inner generally non-accessible zone, an outer zone accessible for performing maintenance functions and an elongated slot between the zones. A reciprocal feed carriage is guidably mounted within the hood in the inner zone and mounts a seal support housing within the outer zone. Portions of the housing extend through the slot into the inner zone and are pivotally mounted upon the carriage. A rotating shaft and seal assembly is mounted upon the seal support housing in the outer zone, including a body having a water inlet adapted for connection to a source of water under pressure. An elongated tubular shaft and nozzle assembly is axially connected to the rotatable seal and shaft assembly and extends from the seal support housing through the slot into the inner zone of the hood, through the carriage and into the bottom of the hood for directing water under pressure against the structural concrete.

Abstract: Discrete volumes, or slugs, of liquid are accelerated to high velocities utilizing energy stored by compressing the liquid. Liquid is forced into a pressure vessel already filled with liquid to effect the compression. A slug of liquid is ejected from the pressure vessel into a cumulation nozzle by the energy stored in the compressed liquid when a valve is rapidly opened. The valve is unseated when an unseating force exceeds a closing bias. The valve is then opened rapidly by an opening force generated by the compressed liquid. By repetitively introducing highly pressurized liquid into the pressure vessel, the valve automatically cycles to generate a series of pulsed liquid jets. Rapid opening of the valve is aided by an extension on the valve member which sealingly slides inside the passage of the cumulation nozzle to block release of liquid until the valve member accelerates sufficiently that the required opening rate is achieved as the extension clears the nozzle passage.

Abstract: A method and apparatus is disclosed for the removal of layers of concrete, particularly from roadways and motorways. This apparatus includes one or more nozzles located at one end of respective hollow shafts each of which is supported by an articulated joint which is mounted on a movable support. The nozzles are supplied with water by means of a high pressure pump upstream of which there is positioned a preliminary treatment system for treating the water itself. The nozzles are mounted on a movable slide or frame which is controlled by an electronic circuit operable to maintain them at a predetermined height with respect to the surface to be treated. Apparatus is also provided for the elimination of possible hindrances to the free downflow of the water jets against the surface to be treated.

Abstract: A roadheader type mining machine (1) comprises a self-propelled chassis (6), an elongate boom (9) having a longitudinal axis (10), rotary cutting head (15) having a plurality of water spray nozzles (17). The boom (9) is of a two-part construction comprising an inner part (18) that is non-rotatable about the boom longitudinal axis (10), that is supported from one end (8) on the chassis (6), and that carries towards its other end (14) bearing means (19) for rotatably supporting an outer part (20) that axially extends from said inner part (18).

Abstract: The method and apparatus for removing structural concrete from a road bed includes a vehicle having a frame on wheels movable along a road bed and mounting a pivotal hood having a lowered use position adjacent the road bed and a raised position. A pressure water manifold upon the frame is connected to a source of pressurized water up to 25,000 p.s.i. A feed carriage is reciprocally mounted within the hood and supports a rotating seal and shaft assembly having a body with a water inlet connected to the manifold and a power rotated tubular shaft journaled upon the body receiving pressure water for delivery to a depending nozzle block connected to and depending from the shaft.

Abstract: A shearer drum for a mining machine used in underground mining is provided with cutter picks and nozzles on the periphery of the drum. The nozzles are subdivided into groups which extend substantially parallel to the rotational axis of the drum and each group of nozzles can, when disposed opposite the mine face, be connected by a controllable valve associated with the group to a line for supplying high-pressure liquid. An independent control valve and at least one cutter pick are associated with each nozzle group. The cutter pick is resiliently mounted and cutting pressure triggered by movement of the cutter pick into a mine face actuates the control valve and connects the nozzles to the high-press line.

Abstract: A method for the extraction of a mineral from an underground unconsolidated formation comprises the steps of:(a) driving a casing through the overburden and into the mineral bearing pay zone,(b) passing a high pressure water jet head and associated supply line down through the casing so that an annulus is formed between the casing and the supply line and the jet head projects just beyond the casing,(c) directing water from the jet head into the pay zone to cause disintegration of the latter,(d) recovering desired product through the annulus between the piping and the casing,(e) moving the jet head to a different level in the pay zone when the previous level is effectively exhausted, and(f) moving the casing in association with the jet head so that the latter remains in the same operating position with respect to the casing with the jet head projecting just beyond the casing.The method is particularly suitable for extracting bitumen from tar sands.

Abstract: An improved hydraulic mining tool apparatus for recovering minerals such as tar sands and the like from subterranean formations is disclosed, wherein plural cutting jet nozzles, adapted to hydraulically dislodge mineral particles from the formation are positioned to generate a hydraulic couple rotational force upon the mining tool and thereby reduce overall power requirements for the apparatus. The plural cutting jet nozzles are connected to one or more flow conduits extending axially within the mining tool apparatus or alternatively may extend from a common sealed reservoir formed within the annulus of the mining tool. The present invention additionally discloses the use of a tri-cone cutting bit assembly positioned upon the lowermost end of the apparatus which may be activated and de-activated from ground surface to selectively provide a rock crushing and force-feeding of mined material during operation as well as during the lowering of the mining tool into the mineral formation.

Abstract: An erosive fluid jet tool for underwater operation, comprising an erosive fluid jet nozzle connected to a fluid receiver receiving fluid under elevated pressure for providing hydraulic power to the tool, the nozzle providing the working output jet of the tool; and a counterthruster for providing a counterthrusting force for balancing the thrust on the tool produced by the erosive fluid jet, the counterthruster including (a) a counterthrusting fluid jet nozzle connected to the fluid receiver and facing oppositely to the erosive nozzle for providing a counterthrusting jet, and (b) an open ended shroud coaxially surrounding the counterthrusting nozzle, whereby water surrounding the submerged tool is entrained through the shroud for providing additional counterthrusting force during operation of the counterthrusting nozzle, the erosive fluid jet nozzle and the counterthruster being constructed so that in excess of 50% of the hydraulic power provided to the tool is provided to the erosive fluid jet nozzle.

Abstract: A rotatable end deflector for an abrasive water jet drill is provided. The end deflector includes two wear resistant plates which direct portions of the water jet in opposite forward directions. Preferably, the abrasive water jet drill includes a source of high pressure water and a high pressure water outlet from which a stream of water is expelled. A venturi device is provided adjacent the water outlet for creating a vacuum. A feed device feeds an abrasive particular material to the venturi device so that the abrasive material is entrained in the stream of water. Thereafter, the stream of water is collimated in a rotating tube which produces a rotating cylindrical water jet which is then deflected before it impinges on the rock to drill the rock. The abrasive material is preferably sand and the tube including the deflector is easily replaceable.

Abstract: Method and apparatus for hydraulically mining a location using a hydraulic monitor which has horizontal and vertical positionable control apparatus. The hydraulic monitor is connected to a source of high pressure water. Distance and direction measuring equipment are mounted on the monitor and controlled in a manner to scan the location. The output from the distance and direction measuring equipment is inputted to a computer and a visual video display monitor. The computer converts the information from the distance and direction measuring equipment to a visual representation of the cavity being mined. The hydraulic monitor includes a means for diverting the high velocity jet during the distance measuring period so that the water pressure is not varied in the high pressure pipe and the mined material is continuously washed toward the collection apparatus during the measuring period. All hydraulic monitor functions are controlled from remote operator location.

Abstract: A liquid discharge control system is provided for nozzles on a shearer or cutter drum for a drum-type shearer loader or heading or drifting machine used in underground mining. In addition to liquid discharge nozzles are distributed about the periphery of the cutter drum there is also provided cutting tools which are distributed about the periphery of the cutter drum. A liquid supply line delivers pressurized water to a valve for each nozzle or a group of nozzles. The valves are operated to control the discharge of water from only those nozzles or group of nozzles which are opposite the mineral face operated on by the cutting tools. The nozzles spray high-pressure jets of water to assist the cutting operation of the tools, to control dust or for suppressing sparks. Electrical control signals are produced to open and close the valves. The control signals are delivered from a microrprocessor which is triggered during rotation of the drum by output signals from one or more initiators.

Abstract: Method and apparatus for crushing the earth under the ground by boring a hole; inserting a drill head having radially directed water jet thereon down the hole to the desired stratum; rotatingly moving the drill head upwardly while jetting water radially to form a cylindrical crushed area; lowering the drill head to the original depth; extending a water jet extender arm radially to a projecting position; again rotatingly moving the drill head upwardly while jetting water from the nozzles on the radial outward portions of the extender arm to radially enlarge the cylindrical crushed area, the rotation of the extender arm also stirring the already crushed area; returning the extender arm to an original waiting position; and lifting the drill head out of the hole.

Abstract: The rotor of a cutter for removal of ore from mine faces has several external material removing bits which are mounted in holders at the exterior of the rotor, and the holders have sockets for discrete spray nozzles which discharge streams of highly pressurized water against the mine face and/or against the bits. The nozzles receive water from discrete conduits whose discharge ends are threadedly connected with the respective nozzles and whose intake ends are connected to the outlets of manifolds which are installed in the interior of the rotor. The conduits extend from the outlets of the respective manifolds and through holes which are provided therefor in the rotor. The sockets in the holders receive spherical joints which allow for changes in orientation of the nozzles with reference to the adjacent bits.

Abstract: A holder for a pick and the combination of a pick and holder.The pick 1 has a shank 4 received in a socket 6 of a holder 2. The holder 2 carries in its socket 6 a tubular spigot 13 which mates in sealed manner with a coupling socket 15 in the pick shank to provide communication for water flow from a supply passage 16a through the pick 1 to outlet ports 12. A shoulder 8 on the spigot 13 abuts a sealing ring 18 in the coupling socket 15 to retain the pick in the holder and permit relative longitudinal displacement therebetween.Carried by the tubular spigot 13 is a valve having an actuating rod 22 which extends through the bore of the spigot. A valve head 24 on the rod 22 is seatable on a shoulder 23a to close off water flow through the bore of the spigot. The end 26 of the rod 22 abuts the pick and during displacement of the pick into its holder in response to cutting engagement of the pick with the mineral, the valve head 24 is displaced to permit water flow to the ports 12.

Abstract: A high pressure water valve (18) supplies water under very high pressure to nozzles (14) for cutting rock or concrete by water jets emitted from the nozzles. A valve plug (30,48) rotates in bearing rings (27) and cooperates with a valve bushing (22;45) of wear resistant high strength material to control the water supply to the nozzles via one or more valve openings (28;51) in said bushing or plug. High pressure water in a pressure opening (33;47) in respectively the plug or bushing forces the plug to sealingly occlude one or more valve openings (28;51) disposed diametrically opposite to said pressure opening.

Abstract: A mineral cutter pick 1 comprises a head 2 terminating at one end thereof in a hard material tip 3, an integral shank 4 extending from the head 2 in a direction away from the tip 3, at least one laterally extending shoulder 5 provided on the head 2, and a bore 6 extending through the shoulder 5, generally in the longitudinal direction 8 of the pick 1, through which bore 6 a water spray or jet may be passed.

Abstract: A pre-bolting system for underground mines which comprises narrow, deep slots in the working face and in drilling through at an angle and bolting from inside these slots with equipment specially designed for this purpose. The drilling, bolting equipment uses high pressure water to assist drilling by water jet. The bit can also be driven by an axial water turbine of small diameter located at the bit. The equipment includes a ventilation system to dilute gas inside the slot when drilling or bolting.

Abstract: A mineral cutting device comprises a plurality of replaceable picks (10, 10A-10G) and associated water conveying lances (20, 20A-20G), each lance being of flexible, tubular synthetic plastics material having a hollow, water-conveying interior and being contained, at least partially, within a bore (13, 13A, 13B) in the pick (10, 10A-10G) when the pick (10, 10A-10G) has been mounted on the device (1, 1A, 1B), to line the bore and prevent water pressure within the lance being effective on the pick, with a terminal end of each lance provided with a metallic nozzle secured in water sealing manner thereto and providing a water discharge orifice (23). The invention further includes a lance (20, 20A-20G) for use with the mineral cutting device defined above, and also a shank bore (13B) formed at least partially in a side (27) of the pick shank (12, 12A-12D), which, in use, is the compressive stress side, and/or with an inner bore end (15) intersected by a slot (42) provided in at least a portion of the shank (12D).

Abstract: Apparatus for removing material from a surface, for use in association with a source of water at a pressure within the range of about 10,000 to 25,000 psi, the apparatus comprising, a carriage vehicle, extendable arm mounted on the vehicle and defining a free end, a nozzle being movable in a transverse direction, the nozzle including a housing and a rotatable nozzle mounted thereto, a hose connecting the source of water to the nozzle, a motor attached to the nozzle operable to rotate the nozzle, and an extender attached between the arm and the vehicle operable to extend and retract the arm relative to the vehicle.

Abstract: Apparatus for the removal of layers of concrete, particularly from roadways and motorways. This apparatus includes nozzles positioned at one end of respective hollow shafts supported by a ball joint and mounted on movable supports. The said nozzles are supplied with water by means of a high pressure pump upstream of which there are positioned preliminary treatment systems for treating the water itself. The nozzles, moreover, are mounted on a slide controlled by electronic apparatus operable to maintain them at a predetermined height with respect to the surface to be scarified. Means are also provided for the elimination of possible hindrances to the free downflow of the water jets against the surface to be scarified.

Abstract: A process is disclosed for cutting rock by means of discharging a medium under high pressure from a nozzle head at a fixed oscillating angle. A nozzle head on the end of the pressure hose is set in a freely pulsating movement through the discharge of a medium under high pressure. The movement of the nozzle head is controlled by a guide with stops. An apparatus for carrying out this process is also disclosed. The apparatus comprises a suitable nozzle head on a delivery line 1 for discharging a medium under high pressure and with a fixed oscillating angle and a guide 6 with stops 4. A flexible high-pressure hose is used as the delivery line 1.

Abstract: A mineral cutter pick is mounted in a holder. Passages in the pick and the holder supply fluid to an opening near the pick cutting edge. Sleeves are provided in the adjacent ends of the passages in the pick and holder and receive the opposite ends of a tubular connector. At least one of the sealing sleeves has its outer face exposed to the fluid supply pressure so that sealing with the associated end of the connector is assisted by the pressure force. The ends of the connector are formed as spherical enlargements to allow free pivoting in their sleeves and at least one end is axially displaceable in its sleeve while maintaining sealing contact.

Abstract: A device for removing degraded concrete from a layer of concrete (11). The device includes a carrier (12) and a guide mechanism (13) on the carrier for guiding a nozzle device (14) along a path above the concrete layer. The nozzle device is provided with a noncavitating nozzle (16) which is inclined relative to the concrete layer such that the nozzle points in the direction of movement of the nozzle device for either direction of movement of the nozzle device.

Abstract: The invention is an improvement in borehole mining which overcomes the conventional problem in hydraulic mining of removing rock fragments and ore from beneath the surface by utilizing a foam/air conveyance technique. This eliminates the need for a pump and overcomes the drawback of short pump life that is ordinarily encountered when pumps are engaged in pumping fluid slurries containing a high component of fragmented rock. A foaming agent, such as an organic sulfonic acid surfactant is introduced into the borehole, preferably combined in the water used to dislodge the particles thereby foaming during mining. The foam containing the entrained particles is removed to the surface by a gas, e.g., air under sufficient pressure and rate to maintain the flow from the well bore. The foam is broken at the surface by conventional methods and the mined particles recovered.

Abstract: The liquid jet cutting apparatus contains a cutter head with a nozzle block and a jet exit opening which communicates with a jet discharge passage. A jet of a pressurized liquid cutting medium is formed in the cutter head and the jet exiting from the jet exit opening passes through the jet discharge passage without contacting the wall thereof. The jet discharge passage communicates through an opening in its wall with a pressure transmission line connecting a gas space formed in the jet discharge passage with a pressure sensor. A transmitter is operatively associated with the pressure sensor and is operated when the pressure in the gas space of the jet discharge passage exceeds or drops below a predetermined pressure threshold value. The transmitter acts upon an actuator or control member of a cut-off device or throughflow regulator which is arranged in the liquid supply line which supplies the pressurized liquid cutting medium to the cutter head.

Abstract: A method is disclosed which allows an overburdened area over an underground mine cavity to be supported by the initiation of foam on liquid retained in the cavity which liquid results from the hydraulic borehole mining of minerals in the cavity.

Abstract: A pressurized fluid is injected into a subterranean cavity in a mineral deposit to support the overburden during hydraulic mining operations. A dynamic seal between the drill string and a surrounding casing retains fluid pressure within the cavity as the drill string rotates during mining operations. A blowout protector retains fluid pressure within the cavity while the drill string is raised or lowered within the cavity when it is necessary to add or remove drill string sections.

Abstract: Discrete volumes, or slugs, of liquid are accelerated to high velocities utilizing energy stored by compressing the liquid. Liquid is forced into a pressure vessel already filled with liquid to effect the compression. A slug of liquid is ejected from the pressure vessel into a cumulation nozzle by the energy stored in the compressed liquid when a valve is rapidly opened. The valve is opened when an opening force, generated by the compressed liquid, exceeds a closing bias. By repetitively introducing highly pressurized liquid into the pressure vessel, the valve automatically cycles to generate a series of pulsed liquid jets. Rapid opening of the valve is aided by an extension on the valve member which sealingly slides inside the passage of the cumulation nozzle to block release of liquid until the valve member accelerates sufficiently that the required opening rate is achieved as the extension clears the nozzle passage.

Abstract: Instead of teeth or similar cutting or loosening means, oscillating nozzles are arranged on the outer backs and the outer side walls of the buckets of the bucketwheel of a bucketwheel excavator, the nozzles being capable of being supplied with liquid, in particular water, at high pressure. These nozzles enable the excavator to strip or mine deposits of high hardness and strength as well as highly abrasive deposits with reduced outage periods and reduced force required for digging as well as lower capital costs and operating costs. In addition to the oscillating nozzles, fixed nozzles may additionally be provided which produce cuts in the material to be excavated whereby the formation of large lumps is prevented.