Tunneling machine having liquid balance low flow slurry system

A liquid balance system in a tunneling machine for supporting a tunnel face by a low slurry flow, the tunneling machine including a rotatable cutterhead having a plurality of cutting units and having muck openings communicating with a cutterhead chamber, said liquid balance system comprising:

• a removable bulkhead forming part of the cutterhead chamber enabling pressurization of the cutterhead chamber and the tunnel face;
• inlet means through said bulkhead and into the cutterhead chamber permitting passage of low flow slurry into the cutterhead chamber at a rate maintaining the desired pressure in the cutterhead chamber and at the tunnel face;
• conveyor means through said bulkhead and out of the cutterhead chamber for removal of tunneled material from the cutterhead chamber, said conveyor means being associated with said bulkhead in a manner permitting the maintaining of the desired pressure in the cutterhead chamber and at the tunnel face;
• pressure lock means receiving tunneled material from said conveyor means and transporting the tunneled material for processing at substantially atmospheric pressure;
• means connected to said pressure lock means for processing said tunneled material to remove most of the solids therefrom;
• reservoir/accumulator means connected to said means for processing tunneled material, said reservoir/accumulator means also being connected to said inlet means for passage of low flow slurry into the cutterhead chamber, said reservoir/accumulator means functioning to control the flow rate of the low flow slurry through said inlet means to match the removal of tunneled material by said conveyor means to maintain the desired liquid balance pressure in the cutterhead chamber and at the tunnel face;
• and
• second conveyor means adapted to be inserted into said cutterhead chamber upon removal of said bulkhead, said second conveyor means being adapted to transport material tunneled from the tunnel workface at substantially atmospheric pressure when the tunnel workface is self-supporting.

A tunneling machine employing a liquid balance system with a low slurry flow, said tunneling machine comprising:

• a main frame;
• a cutterhead having a plurality of cutting units and having muck passages communicating with a cutterhead chamber, said cutterhead being rotatable relative to said main frame;
• means for rotating said cutterhead relative to said main frame;
• a removable bulkhead attached to the cutterhead chamber for pressurization of the cutterhead chamber and the tunnel face;
• inlet means through said bulkhead and into the cutterhead chamber for passage of the low flow slurry through the cutterhead chamber to maintain the desired pressure in the cutterhead chamber and at the tunnel face;
• conveyor means through said bulkhead and into the cutterhead chamber for removal of tunneled material from the cutterhead chamber and the tunnel face, said conveyor means attached to said bulkhead to maintain the desired pressure in the cutterhead chamber and at the tunnel face;
• pressure lock means external to said bulkhead and the cutterhead chamber and attached to said conveyor means, said pressure lock means being adapted to receive tunneled material from said conveyor means and to transport the tunneled material for processing at substantially atmospheric pressure while maintaining the desired pressure in the cutterhead chamber and at the tunnel face;
• means for processing said tunneled material, said means for processing connected to said pressure lock means;
• reservoir/accumulator means connected to said means for processing tunneled material, said reservoir/accumulator means being also connected to said inlet means for passage of low flow slurry into the cutterhead chamber, said reservoir/accumulator means being also adapted to control the flow rate of the low flow slurry through said inlet means to means the removal of tunneled material by said conveyor means to maintain the pressure in the cutterhead chamber and at the tunnel face;
• and
• second conveyor means adapted to be inserted into said cutterhead chamber upon removal of said bulkhead, said second conveyor means adapted to transport material tunneled from a self-supporting tunnel face at substantially atmospheric pressure.