Method and apparatus for high pressure radial pulsed jetting of lateral passages from vertical to horizontal wellbores

A method for jet forming multiple lateral passages from a wellbore intersecting a subsurface formation and being lined with a casing, comprising:

• securing an indexing mechanism at a desired position within a wellbore, the indexing mechanism having a first indexing profile;
• running a casing cutting mechanism having a second indexing profile and a casing cutter through the wellbore and landing said casing cutting mechanism in rotationally indexed relation with said indexing mechanism with said second indexing profile in engagement with said first indexing profile;
• rotating and advancing said casing cutter and cutting a lateral passage opening in the casing;
• disengaging said second indexing profile from said first indexing profile, rotating said casing cutting mechanism to a different rotationally indexed position within the wellbore and re-engaging said second indexing profile in rotationally indexed engagement with said first indexing profile;
• again rotating and advancing said casing cutter and cutting another lateral passage opening in the casing;
• repeating said disengaging, rotating and re-engaging steps until a desired number of lateral passage openings have been cut in the casing;
• and
• retrieving said casing cutting mechanism from the wellbore.

Apparatus for jet forming a plurality of lateral passages extending from a casing lined wellbore into the surrounding formation, comprising:

• an indexing mechanism being secured at a desired location and selected rotational orientation within a wellbore and defining a first indexing profile;
• a casing cutting mechanism having a tubular conveyance body and a deflector shoe mounted to said tubular conveyance body and defining a second indexing profile being positionable in indexed relation with said first indexing profile;
• a deflector shoe being mounted to said tubular deflector body, said deflector shoe defining a shaft guide passage and defining a second indexing profile positioned for indexing engagement with said first indexing profile and defining a shaft guide passage;
• an internal drive member being supported within said tubular conveyance body and having a rotary motor;
• a flexible drive shaft being rotated by said rotary motor and being located within said shaft guide passage;
• a cutter device being mounted to said flexible drive shaft and cutting an opening in the casing upon motor operated rotation of said flexible drive shaft and advancing movement of said flexible drive shaft and cutter device.