Sealing body for well perforation operations

Abstract

A sealing body is provided for use in well operations such as oil/gas well perforation operations. The sealing body comprises a shell defining a closed cavity; the shell is comprised of a metal alloy. The sealing body has neutral or positive buoyancy. In one embodiment, the sealing body further comprises a reinforcement structure in the cavity. The reinforcement structure may comprise one or more pairs of ribs adjoining an inner surface of the shell of the sealing body.

What is claimed is: 
     
         1 . A sealing body for use in well perforation operations, the sealing body comprising:
 a shell defining a closed cavity;   wherein the shell is comprised of a metal alloy; and   wherein specific gravity of the sealing body is less than or equal to 1, where 1 is the specific gravity of water.   
     
     
         2 . A sealing body for use in well perforation operations according to  claim 1  wherein the metal alloy is a titanium alloy. 
     
     
         3 . A sealing body for use in well perforation operations according to  claim 2  wherein the titanium alloy is Ti-6Al-4V. 
     
     
         4 . A sealing body for use in well perforation operations according to  claim 1 , wherein the shell is substantially spherical. 
     
     
         5 . A sealing body for use in well perforation operations according to  claim 1 , further comprising a reinforcement structure within the cavity. 
     
     
         6 . A sealing body for use in well perforation operations according to  claim 5  wherein the reinforcement structure comprises one or more pairs of ribs adjoining an inner surface of the shell. 
     
     
         7 . A sealing body for use in well perforation operations according to  claim 6  wherein each rib of the one or more pairs of ribs extends in a circle adjoining the inner surface of the shell and wherein, for each pair, planes of the circles of the ribs are orthogonal. 
     
     
         8 . A sealing body for use in well perforation operations according to  claim 6  wherein the ribs are spaced evenly within the cavity. 
     
     
         9 . A sealing body for use in well perforation operations according to  claim 6  wherein each rib has a substantially square cross section. 
     
     
         10 . A sealing body for use in well perforation operations according to  claim 9  wherein the cross section of each rib is 2 mm×2 mm. 
     
     
         11 . A sealing body for use in well perforation operations according to  claim 1 , wherein the shell has:
 an inner surface, an outer surface and an outside diameter in a range of 2.25 to 3.5 inches;   a thickness between the inner surface and the outer surface in a range of 0.085 to 0.135 inches;   wherein the metal alloy comprises a titanium alloy; and   wherein the specific gravity of the sealing body is less than 1.   
     
     
         12 . A sealing body for use in well perforation operations according to  claim 5 , wherein the shell has
 an inner surface, an outer surface and an outside diameter in a range of 1.25 to 2.0 inches;   a thickness between the inner surface and the outer surface in a range of 0.042 to 0.06 inches.   
     
     
         13 . A sealing body for use in well perforation operations according to  claim 5 , wherein the metal alloy is a titanium alloy. 
     
     
         14 . A sealing body for use in well perforation operations according to  claim 7  comprising one pair of ribs wherein the planes of the circles of the ribs intersect a center of the sealing body. 
     
     
         15 . A sealing body for use in well perforation operations according to  claim 7  wherein:
 the outside diameter is in the range of 1.25 to 1.5 inches; 
 the thickness between the inner surface and the outer surface is in the range of 0.042 to 0.055 inches; and 
 wherein the metal alloy comprises a titanium alloy. 
 
     
     
         16 . A sealing body for use in well perforation operations according to  claim 7  comprising two pairs of ribs wherein each of the four ribs are offset from a center of the sealing body. 
     
     
         17 . A sealing body for use in well perforation operations according to  claim 16  comprising wherein:
 the outside diameter is 1.75 inches; 
 the thickness between the inner surface and the outer surface is 0.055 inches; and 
 wherein the metal alloy comprises a titanium alloy. 
 
     
     
         18 . A sealing body for use in well perforation operations according to  claim 7  comprising three pairs of ribs wherein four of the six ribs are offset from a center of the sealing body and wherein the planes of the circles of the other two ribs intersect a center of the sealing body. 
     
     
         19 . A sealing body for use in well perforation operation according to  claim 18  comprising wherein:
 the outside diameter is 2 inches; 
 the thickness between the inner surface and the outer surface is 0.06 inches; and 
 wherein the metal alloy comprises a titanium alloy. 
 
     
     
         20 . A sealing body for use in well perforation operations according to  claim 1  wherein the cavity is evacuated of gas or liquid. 
     
     
         21 . A sealing body for use in well perforation operation according to  claim 1  wherein the cavity is filled with a gas or a liquid. 
     
     
         22 . A sealing body for use in well perforation operations according to  claim 6  wherein the one or more pairs of ribs are comprised of a titanium alloy. 
     
     
         23 . A sealing body for use in well perforation operations according to  claim 21  wherein the titanium alloy comprises a Ti-6Al-4V titanium. 
     
     
         24 . A sealing body for use in well perforation operations according to  claim 1  wherein the outer surface of the sealing body comprises an irregular surface. 
     
     
         25 . A method of performing well perforation operations comprising:
 introducing a sealing body into a seat positioned in a well bore, the sealing body comprising a shell defining a closed cavity, wherein the shell is comprised of a metal alloy; and wherein specific gravity of the sealing body is less than or equal to 1, where 1 is the specific gravity of water; and   pressurizing a portion of the well bore up-hole from the seat to a predetermined pressure threshold for triggering a perforating gun.