System of pipes for use in oil wells

Abstract

The present invention relates to pipes that convey any flowable medium, such as chemicals, food and in particular, oil and gas, and more particularly to a system of pipes having different coatings or linings for the interior and exterior surfaces of such pipes, depending on the environment in which the pipes are used. The pipes may be coated with different materials, which may be of different thicknesses, with various configurations of coatings or linings. Such coating may be done on the interior and/or the exterior of the pipes.

1 . A system of pipes for conveying flowable media comprising a first pipe and a second pipe having a lining adhered to the interior surface of the pipe, and the lining of the second pipe comprises a primer layer adhered to the interior surface of the pipe and an overcoat or a preformed film comprising a fluoropolymer adhered to the primer layer.  
   
   
       2 . A system of pipes for conveying flowable media comprising a first pipe and a second pipe having a lining adhered to the interior surface of the pipe, and the lining of the second pipe consists essentially of a perfluoropolymer.  
   
   
       3 . A system of pipes for conveying flowable media comprising a first pipe and a second pipe having a lining adhered to the interior surface of the pipe, and the lining of the second pipe comprises a barrier layer including a plurality of particles which form a mechanical barrier against permeation of water, gas and solvents to the pipe.  
   
   
       4 . The system of claims  1 ,  2  or  3 , wherein the first pipe is unlined.  
   
   
       5 . The system of claims  1 ,  2  or  3 , wherein the first pipe is lined with a different material than the second pipe.  
   
   
       6 . The system of  claim 3 , wherein the different material of the first pipe comprises fluorinated ethylene propylene.  
   
   
       7 . The system of  claim 3 , wherein the different material of the first pipe comprises epoxy.  
   
   
       8 . The system of  claim 2 , wherein the primer layer comprises a perfluoropolymer.  
   
   
       9 . The system of  claim 8 , wherein the overcoat also comprise a perfluoropolymer.  
   
   
       10 . The system of claims  1 ,  2  or  3 , wherein the thickness of the lining in the section of the pipe at a depth of 1500 feet or greater below the surface is 5 mil.  
   
   
       11 . The system of claims  1 ,  2  or  3 , wherein the thickness of the lining in the section of the pipe at a depth of 1500 feet or less is 40-50 mils.