Non-clogging slurry nozzle apparatus and method

A non-clogging, high pressure slurry nozzle apparatus for intermittantly jetting an abrasive material in combination with a high pressure fluid stream, comprising:

• a nozzle for receiving the high pressure fluid stream having a first orifice in operative association with a high pressure fluid conduit, through which the high pressure fluid stream passes and a second orifice in operative association with a high pressure flow conduit through which one of abrasive material and a supply compressed gas selectively enters and an outlet through which one of the high pressure fluid stream in combination with the abrasive material, and the supply of compressed gas are selectively jetted;
• a trigger for selectively jetting the high pressure fluid stream through the outlet;
• a dump means for venting the high pressure fluid stream away from the outlet;
• a high pressure fluid pump to supply the high pressure fluid stream to the first orifice;
• a pressure actuator, having a pressure sensing means and a two position switch, in communication with said high pressure fluid stream;
• a valve for controlling the flow of one of abrasive material and a supply of compressed gas selectively to the second orifice of said nozzle;
• a supply of the abrasive material selectively transmitted through said valve and through the high pressure flow conduit engaged to the second orifice of said nozzle, wherein said abrasive material commingles with said high pressure fluid stream and a mixture of high pressure fluid and abrasive material is jetted from said outlet;
• and
• a supply of compressed gas automatically transmitted through said valve and through the high pressure flow conduit to the second orifice of said nozzle for removing abrasive material from said high pressure flow conduit and from said nozzle and from said outlet.

A method for preventing an abrasive material blockage in a non-clogging, high pressure slurry nozzle apparatus, comprising the steps of:

• directing a high pressure fluid stream through an orifice;
• mixing the high pressure fluid stream with an abrasive material to form a mixture;
• jetting the mixture from a nozzle outlet;
• interrupting the jetting of the mixture by directing the high pressure fluid stream away from the orifice to a dump means;
• sensing the interruption in jetting of the mixture and in response thereto engaging an actuator to substitute a supply of compressed gas for the abrasive material;
• and
• jetting the supply of compressed gas automatically, in place of the mixture to prevent blockage and clogging of the nozzle outlet.