Spielvogel\'s experiments in cutting sandstone and granite blocks out of the quarry with a high power water jet have resulted in the Quarry Shark, which they say will transform block extraction.

They say water jet cutting can double production - up to 8m an hour has been achieved in sandstone - compared with drilling, blasting, burning, sawing with diamond wires or chain and belt slotting machines.

Because of the way the cutting head enters into the cut, the only limitation on the size of block that can be produced is the length of hoses and it is perfectly feasible to produce blocks 5m deep.

Installation involves high pressure pumps, water-tank with pump and filter, carriage on rails with a mast, lance with patented nozzle cap and a control station.

The chief element of the unit is a 373kW diesel engine powering hydraulics based on two pumps directly driving a double acting cylinder in a closed circuit. The piston is fed from a water cylinder creating the pressure required for the cutting operation. The pumps are automatically controlled to enable a constant water flow with a pressure up to 2,200 bar. The water is recycled.

The units work with minimal wear. Only the seals on the water pump have to be exchanged every 500 to 1,000 hours.

A mast is carriage mounted, with the complete unit travelling on rails. The cutting device is fixed to this mast, which can be moved in the horizontal, vertical and feed direction towards the quarry face. Hydraulic motors drive the carriage and lance and the hydraulic power unit is contained within the carriage.

The Quarry Shark is available now for the first time in the UK from the agents: