Method of controlling pressure in a well

Abstract

A well venting system for controlling the pressure in a tubular element comprising a tubular element having an inner and outer surface forming a wall; and venting means to provide fluid communication between the inside of the inner surface and the outside of the outer surface.

What is claimed is: 
     
         1 . A well venting system for controlling the pressure in a tubular element comprising a tubular element having an inner and outer surface forming a wall; and venting means to provide fluid communication between the inside of the inner surface and the outside of the outer surface. 
     
     
         2 . The system of  claim 1  wherein the tubular element is a drilling liner or casing located in a well. 
     
     
         3 . The system of  claim 1  wherein the venting means may be closed to prevent fluid communication between the inside of the inner surface and the outside of the outer surface. 
     
     
         4 . The system of  claim 1  wherein the venting means may be opened to allow fluid communication between the inside of the inner surface and the outside of the outer surface when the pressure differential across the tubular element wall approaches the collapse rating of the tubular element wall. 
     
     
         5 . A method of controlling the pressure in a tubular element comprising providing a tubular element having an inner and outer surface and venting means that can provide fluid communication from inside the inner surface to outside the outer surface; and activating the venting means to equalize the pressure inside the inner surface with the pressure outside the outer surface. 
     
     
         6 . The method of  claim 5  wherein the tubular element is a drilling liner or casing located in a well. 
     
     
         7 . The method of  claim 5  wherein the venting means is activated when the pressure differential between the outside of the outer surface and the inside of the inner surface approaches the collapse rating of the tubular element. 
     
     
         8 . The method of  claim 5  wherein the venting means is closed when the pressure differential is at a safe pressure for the tubular element.