Abstract:
A tunnel boring machine for boring a tunnel through mixed ground with stable ground conditions and unstable ground conditions. The tunnel boring machine is operable in a stable ground boring mode with the machine anchored to tunnel sidewall portions and also in an unstable ground mode wherein cutting thrust is provided by a shield means in cooperation with tunnel lining structure. Combined mode operation is also possible. The machine comprises a rotatable cutting wheel means positioned at the front end of the machine which may be selectively thrustingly engaged with the tunnel end face for cutting away material away to elongate the tunnel; rotation means operably associated with the rotatable cutter wheel means for selectively causing rotation thereof at various speeds of operation; extendable and retractable central thrust rod means for transmitting forward thrust to the cutting wheel means; central body means for supporting the central thrust rod means in extendable and retractable relationship therein; central thrust generating means operably associated with the central body means for extending and retracting the central thrust rod means; extendable and retractable sidewall engaging means mounted on the central body means for selectively grippingly engaging opposite portions of the tunnel peripheral sidewall; central body support means for supporting the central body means on the floor of the tunnel; annular shield means operably mounted on the central thrust rod means for shielding a forward portion of the machine; extendable and retractable shield thrust means operably associated with the shield means for coacting with the tunnel lining structure to produce forward thrust on the cutting wheel means; muck removal means for removing material cut away from the tunnel face by the cutting wheel means and control means for selectively operating various machine components.
Abstract:
The main frame of the cutterhead comprises a plurality of radial spoke beams which are interconnected between a box-like hub structure and an annular box beam by which the cutterhead is mounted for rotation. Cutter mounting wells are defined by and between side wall portions of the radial spoke beams. The mined material passes rearwardly through the cutterhead via openings between adjacent radial spoke beams and open spaces in the cutter mounting wells. Cutter mounts span laterally between the side plate members and laterally brace the radial spoke beams in addition to mounting the cutters. The radial spoke beams curve rearwardly at their outer ends and connect to the annular box beam at a location spaced enough rearwardly from the front portions of the spoke beams that a room is defined within the cutterhead. Roller type cutters are installed onto and removed from the cutterhead frame from the rear side of the cutterhead.
Abstract:
A diametrically compact tunneling machine for boring tunnels is disclosed. The machine includes a tubular support frame having a hollow piston mounted therein which is movable from a retracted position in the support frame to an extended position. A drive shaft is rotatably mounted in the hollow piston and carries a cutter head at one end. The hollow piston is restrained against rotational movement relative to the support frame and the drive shaft is constrained against longitudinal movement relative to the hollow piston. A plurality of radially extendible feet project from the support frame to the tunnel wall to grip the tunnel wall during a tunneling operation wherein the hollow piston is driven forwardly so that the cutter head works on the tunnel face. When the hollow piston is fully extended, a plurality of extendible support feet, which are fixed to the rearward and forward ends of the hollow piston, are extended, the radially extendible feet are retracted and the support frame is shifted forwardly by the piston so that a further tunneling operation may be initiated.
Abstract:
A vehicle which can easily be dismantled into transportable units and reassembled readily at the tunnel site is provided. A major advantage of this vehicle is the requirement of low thrust during operation and adaptability to use in short tunnels and tunnels with variable rock formations. With only minor adjustments to the drill head assembly and crawler carriage, it is capable of conforming to variable diameters of tunnel sizes. Pneumatic drills in the drill head assembly are guided along the vehicle's path to cut kerfs into the rock. Fluid activated breaker elements enter the kerfs and break out the ridges of rock through smashing blows. The drill head assembly rotates as the kerf cutting process is repeated. The excavated rock is conveyed to the rear of the vehicle for easy disposal. The drills are capable of boring any type of rock, therefore, it is envisioned that this vehicle can excavate soft through very hard formations.
Abstract:
A remote-controlled tunnel boring machine for drilling a substantially horizontal tunnel in a formation includes a rotary drilling head at the heading of the tunnel, and a rotary drill pipe coupled to the drilling head and extending back to the portal of the tunnel for connection to drive means for rotating the drill pipe. The drilling head has fore and aft sections which are movable longitudinally relative to each other, the aft section being coupled with a series of interconnected tunnel liner sections jacked into place behind it from the portal as the drilling head advances through the tunnel. Hydraulic rams between the fore and aft sections periodically advance the drilling head to excavate material at the heading of the tunnel, the weight of the aft section and the tunnel liners acting as a thrust base or back-up for the extension of the rams. A second set of hydraulic rams at the portal periodically force new tunnel liner sections into place behind the string of tunnel liners. Cuttings are continuously removed from the tunnel heading by drilling fluid circulated in a closed system which includes an elongated conduit extending from the portal to the drilling head to continuously supply drilling fluid to the tunnel heading. The cuttings and drilling fluid are continuously returned from the tunnel heading to the portal area through the interior of the constantly rotating drill pipe. A ring-shaped inflatable balloon between the fore and aft sections of the drilling head forms a fluid-tight seal between the inner wall of the tunnel and the exterior of the drilling head to provide controlled hydrostatic fluid pressure at the tunnel heading.