Perforated pipe and apparatus, system and method for perforating a pipe

Abstract

A pipe and system for forming perforations in a pipe are provided. The pipe is for a well bore for filtering materials transported through the pipe and comprises: a wall having an exterior surface and an interior surface, the wall forming the pipe and shaped in a cylinder; and a perforation located in the wall, the perforation for receiving sediment in the materials and forming an aperture in the wall from the exterior surface to the interior surface with a first opening on the exterior surface having a first dimension across a first major axis of the first opening and a second opening on the interior surface having a second dimension across a second major axis of the second opening. The first opening is shaped to be either round, oval, elliptical or racetrack.

1 . A pipe for a well bore for filtering materials entering the pipe, comprising:
 a wall having an exterior surface and an interior surface, the wall forming the pipe; and   a perforation located in the wall, the perforation for receiving and screening the materials and forming an aperture in the wall from the exterior surface to the interior surface with a first opening on the exterior surface having a first dimension across a first major axis of the first opening and a second opening on the interior surface having a second dimension across a second major axis of the second opening,   
       wherein the first opening is shaped to be either round, oval, elliptical or racetrack. 
     
     
         2 . The pipe for a well bore as claimed in  claim 1 , wherein:
 the first opening is round in shape;   the second opening is round in shape; and   the first major axis is smaller than the second major axis.   
     
     
         3 . The pipe for a well bore as claimed in  claim 2 , wherein:
 the perforation is a truncated right cone in shape.   
     
     
         4 . The pipe for a well bore as claimed in  claim 2 , wherein:
 the perforation is a truncated oblique cone in shape.   
     
     
         5 . The pipe for a well bore as claimed in  claim 4 , wherein:
 an axis for the truncated oblique cone is offset in a direction of expected flow of the materials in the pipe.   
     
     
         6 . The pipe for a well bore as claimed in  claim 4 , wherein:
 an axis for the truncated oblique cone is offset oblique to a direction of expected flow for the pipe.   
     
     
         7 . The pipe for a well bore as claimed in  claim 1 , wherein:
 the first opening is round in shape;   the second opening is round in shape; and   the first major axis is larger than the second major axis.   
     
     
         8 . The pipe for a well bore as claimed in  claim 1 , further comprising:
 a second perforation located in the wall, the second perforation forming a second aperture in the wall from the exterior surface to the interior surface with a third opening on the exterior surface having a third dimension across a third major axis of the third opening and a fourth opening on the interior surface having a fourth dimension across a fourth major axis of the fourth opening,   
       wherein at least one of the third or fourth dimensions is different from the corresponding first or second dimensions. 
     
     
         9 . The pipe for a well bore as claimed in  claim 8 , wherein:
 the second perforation is located in a line of a direction of flow of the materials in the pipe with the perforation.   
     
     
         10 . The pipe for a well bore as claimed in  claim 8 , wherein:
 the second perforation is located in offset from a line of a direction of flow of the materials in the pipe with the perforation.   
     
     
         11 . The pipe for a well bore as claimed in  claim 8 , wherein:
 the third dimension of the second perforation is larger than the first dimension of the perforation.   
     
     
         12 . The pipe for a well bore as claimed in  claim 8 , wherein:
 the third dimension of the second perforation is smaller than the first dimension of the perforation.   
     
     
         13 . The pipe for a well bore as claimed in  claim 1 , further comprising:
 a slot located in the wall, the slot being in proximity to the perforation at a location in the pipe that is in a direction of flow of the materials in the pipe.   
     
     
         14 . The pipe for a well bore as claimed in  claim 13 , wherein:
 edges of an interior opening of the slot are rounded by a water jet.   
     
     
         15 . The pipe for a well bore as claimed in  claim 1 , wherein the wall is shaped in a cylinder. 
     
     
         16 . The pipe for a well bore as claimed in  claim 1 , wherein:
 the perforation is formed by a water jet applied to the exterior surface of the pipe; and   a sacrificial pipe is placed in the interior of the pipe as the water jet forms the perforation.