Methods of perforating a well using coiled tubing

A method of perforating a casing of a well, comprising:

• (a) providing a perforating tool string including:
• a coiled tubing string;
• a perforating gun;
• a releasable gun hanger connected to said perforating gun, said gun hanger being actuatable by reciprocating non-rotating motion;
• and
• a pressure responsive release connecting said coiled tubing string to said perforating gun;
• (b) lowering said perforating tool string into said casing until said perforating gun is adjacent a subsurface formation to be perforated;
• (c) actuating said gun hanger by reciprocating motion of said coiled tubing string without rotating said coiled tubing string, and thereby setting said gun hanger in said casing;
• (d) increasing fluid pressure in said coiled tubing string and thereby releasing said pressure responsive release from said perforating gun;
• (e) retrieving said coiled tubing string and said pressure responsive release from said well before firing said perforating gun so that said coiled tubing string is not exposed to explosive forces generated by said perforating gun;
• (f) firing said perforating gun and perforating said casing;
• and
• (g) releasing said gun hanger from said casing after firing of said perforating gun, and dropping said perforating gun and said releasable gun hanger to a bottom of said well.

A pressure actuated release assembly for releasably connecting a tubing string to a well tool in a well, comprising:

• a fishing neck adapted to be attached to said well tool and to extend upwardly from said well tool, said fishing neck having an enlarged head defined on an upper end thereof, said enlarged head having a valve closure surface defined thereon;
• a housing having a housing bore, said housing including an upper connector means for connecting said housing to said tubing string so that said housing bore is communicated with a tubing bore of said tubing string, said housing having an annular valve seat defined therein, said enlarged head of said fishing neck being slidably received in said housing bore and slidable between an open position wherein said valve closure surface and said valve seat are spaced apart, and a closed position wherein said valve closure surface engages said valve seat to close said housing bore;
• a releasable latch means connected to said housing and operably associated with said fishing neck for retaining said enlarged head in said housing bore when said latch means is in a latched position;
• a hydraulic releasing piston communicated with said housing bore above said valve seat, and operably associated with said releasable latch means, said piston being movable from a first position corresponding to said latched position of said releasable latch means to a second position corresponding to an unlatched position of said releasable latch in response to an increase in fluid pressure in said tubing bore when said fishing neck is in its said closed position closing said housing bore.

A pressure actuated release apparatus for releasably connecting a tubing string to a well tool in a well, comprising:

• a housing having a housing bore, said housing including a connection means for connecting said housing to said tubing string with said housing bore communicated with a tubing bore of said tubing string;
• releasable latch means disposed in said housing for releasably latching said housing to said well tool;
• an actuating piston means, disposed in said housing and communicated with said housing bore, for moving said latch means from a latched position to an unlatched position in response to an increase in fluid pressure in said tubing bore;
• and
• closeable fill-up valve means, disposed in said housing, for allowing said tubing bore to fill with well fluid as said tubing string and said well tool are run into said well, and for closing said tubing bore so that said actuating piston may be operated to unlatch said well tool after said well tool is run into said well, said closable fill-up valve means including an annular valve seat defined in said housing and surrounding said housing bore, and a closure valve surface defined on said well tool.