LIQUID JET GENERATION METHOD AND DEVICE Russian patent published in 2007 - IPC E21C45/04 

FIELD: methods of hydraulic mining, hydraulic monitors, particularly devices to generate high-velocity jets in hydraulic cutting devices adapted, for instance, for hydrodynamic high-strength metal structure and rock cutting.

SUBSTANCE: method involves forcing accelerated flow through annular nozzle to create liquid jet shaped as hollow cone at nozzle end along with following hollow cone jet collapse and secondary high-velocity jet generation. Accelerated flow is additionally mixed with abrasive particles inside mixing chamber. Reverse jet mixed with abrasive particles is deflected from cutting zone and passes into accumulation chamber. Liquid jet forming device comprises body 1 with jet generation means 2 and mixing chamber 3 for liquid mixing with abrasive particles, collimator 4 and pipe 5 to deliver abrasive particles to mixing chamber 3. Device also has insert 6 arranged in body 1 and including reverse jet accumulation chamber located in lower part thereof. Connected to reverse jet accumulation chamber is lid 9 fastened to upper chamber part by means of bolts 8. Lid 9 is threadedly connected to the body. Mixing chamber 3 and collimator 4 are defined by inner annular body surface and outer annular insert 6 surface.

EFFECT: increased hydroabrasive cutting efficiency without high-pressure apparatus power increase due to increased impact action applied by liquid jet to material to be cut.

2 cl, 3 dwg, 1 ex