Telescopic laser purge nozzle

摘要

A method and apparatus for wellbore perforation in which a laser beam at a downhole location of a wellbore is directed to a target area of a wellbore wall to be perforated. The laser beam is guided through a longitudinally extensible nozzle onto the target area and a purge fluid is introduced into the longitudinally extensible nozzle, thereby longitudinally extending the nozzle toward the target area. The purge fluid in the longitudinally extensible nozzle is passed through a purge fluid outlet of the nozzle onto the target area, thereby removing debris from the target area generated by the laser beam.

主权项

1. An apparatus for wellbore perforation comprising: a drill string having a downhole end; a laser energy source; laser energy transmission means for transmitting laser energy from said laser energy source to said downhole end of said drill string; a longitudinally extensible nozzle extendable between an extended position and a retracted position having a drill string end connected with said downhole end of said drill string and having a drilling end, said nozzle adapted to transmit said laser energy from said downhole end of said drill string to said drilling end; said longitudinally extensible nozzle having a purge fluid inlet in fluid communication with a purge fluid source and having a purge fluid outlet proximate said drilling end; a rotary drill bit connected with said drilling end of said longitudinally extensible nozzle; and a pneumatically driven rotary vane motor disposed within said longitudinally extensible nozzle proximate said drilling end and adapted to rotate said rotary drill bit.