Device and method to reduce breakdown/fracture initiation pressure

Abstract

A slim perforating gun includes a plurality of shape charges; a positioning device that orients the perforating gun in relation to a down direction of a deviated well; the shaped charges being positioned inside the perforating gun and aimed in predetermined directions with respect to the down direction of the deviated well; wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of a casing used in connection with the slim perforating gun is from 0.85 to 0.30.

1 . A slim perforating gun system, comprising:
 a plurality of shape charges;   a positioning device that orients the perforating gun in relation to a down direction of a deviated well;   the shape charges being positioned inside the perforating gun and aimed in predetermined directions with respect to the down direction of the deviated well;   wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of a casing used in connection with the slim perforating gun is from 0.85 to 0.30.   
     
     
         2 . The slim perforating gun of  claim 1 , wherein the directions of the shape charges are phased approximately 180 degrees. 
     
     
         3 . The slim perforating gun of  claim 1 , wherein the directions of the shape charges are phased approximately at 0, +/−60 degrees. 
     
     
         4 . The slim perforating gun of  claim 1 , wherein the directions of the shape charges are phased approximately at +/−90, +/−30 degrees. 
     
     
         5 . The slim perforating gun of  claim 1 , wherein the positioning device comprises at least one selected from the following: magnetic device, centralizer springs, mechanical caliper devices, and fins. 
     
     
         6 . The slim perforating gun of  claim 5 , wherein the positioning device positions the perforating gun with the shape charges pointing in a direction perpendicular to a shortest path to the casing. 
     
     
         7 . The slim perforating gun of  claim 1 , comprising a swivel to decouple torque from a cable. 
     
     
         8 . The slim perforating gun of  claim 1 , wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of the casing used in connection with the slim perforating gun is from 0.80 to 0.40. 
     
     
         9 . The slim perforating gun of  claim 1 , wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of the casing used in connection with the slim perforating gun is from 0.7 to 0.40. 
     
     
         10 . The slim perforating gun of  claim 1 , wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of the casing used in connection with the slim perforating gun is from 0.6 to 0.4. 
     
     
         11 . A method of perforating a subterranean hydrocarbon well, the method comprising:
 determining an azimuth for at least a portion of a deviated well;   placing a slim perforating gun in the well and using a positioning device to locate the perforating gun proximate to a casing in the deviated well in down direction;   positioning a plurality of shape charges in the slim perforating gun in predetermined directions with respect to the down direction;   wherein an outer diameter of the slim perforating gun and an inner diameter of a casing used in connection with the slim perforating gun has a ratio from 0.85 to 0.30.   
     
     
         12 . The method of  claim 11 , comprising positioning the shape charges so that the directions of the shape charges are phased approximately 180 degrees. 
     
     
         13 . The method of  claim 11 , comprising positioning the shape charges so that the directions of the shape charges are phased approximately at 0, +/−60 degrees. 
     
     
         14 . The method of  claim 11 , comprising positioning the shape charges so that the directions of the shape charges are phased approximately at +/−90, +/−30 degrees. 
     
     
         15 . The method of  claim 11 , wherein the positioning device comprises at least one selected from the following: magnetic device, centralizer springs, mechanical caliper devices, and fins. 
     
     
         16 . The method of  claim 15 , comprising using the positioning device to position the perforating gun with the shape charges pointing in a direction perpendicular to a shortest path to the casing. 
     
     
         17 . The method of  claim 11 , wherein the azimuth of the well is substantially in a direction of minimal horizontal stress. 
     
     
         18 . The method of  claim 11 , wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of the casing used in connection with the slim perforating gun is from 0.80 to 0.40. 
     
     
         18 . The method of  claim 11 , wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of the casing used in connection with the slim perforating gun is from 0.6 to 0.40. 
     
     
         20 . A method for treating multiple intervals of one or more subterranean formations intersected by a cased wellbore, said method comprising:
 a) using a perforating device to perforate at least one interval of said one or more subterranean formations;   b) pumping a treating fluid into the perforations created in said at least one interval by said perforating device without removing said perforating device from said wellbore;   c) deploying one or more diversion agents in said wellbore to removably block further fluid flow into said perforations; and   d) repeating at least steps a) through b) for at least one more interval of said one or more subterranean formations; wherein at some time after step a) and before removably blocking fluid flow into said perforations, said perforating device is moved to a position above said at least one interval perforated in step a);   wherein the perforating device comprises a slim perforating gun, comprising:   a plurality of shape charges;   a positioning device that orients the perforating gun in relation to a down direction of a deviated well;   the shape charges being positioned inside the perforating gun and aimed in predetermined directions with respect to the down direction of the deviated well;   wherein a ratio of the outer diameter of the slim perforating gun to the inner diameter of a casing used in connection with the slim perforating gun is from 0.85 to 0.30.