Method for manufacturing reinforced thermoplastic pipes

Abstract

A process for manufacturing pipes using thermoplastic pipe and “tape” (continuous fiber, fully wetted in a similar thermoplastic as the pipe) that embeds the fibers into pipe surface. In one embodiment, an ambient temperature (72 degrees F.) tape is tightly wrapped around the cold pipe in a dry environment (relative humidity below 30). An external heat source is used to heat up the entire length of the pipe causing the thermoplastic to melt and the pipe to expand due to thermal expansion. Since the fibers have less stretch than the thermal expansion of the pipe the fibers will be embedded into the molten layer of the pipe, creating a permanent bond between the fibers and the pipe. A protective film is applied to the pipe. Portions of the tape and film are scraped from the surface of the pipe creating an area where the end of the pipe is coupled to another pipe using an electronic fusion coupler.

What is claimed is: 
     
         1 . A method for manufacturing a reinforced pipe system for transporting a fluid, comprising:
 cooling a thermoplastic pipe;   wrapping a fiber tape on a surface of the thermoplastic pipe, said fiber tape having continuous taut fibers;   warming the fiber tape and thermoplastic pipe using a heat source;   embedding the taut fibers into the thermoplastic pipe as the thermoplastic pipe is warmed; and   melting the fiber tape and the thermoplastic pipe to create a bond.   
     
     
         2 . The method of  claim 1 , where the bond is a homogenous. 
     
     
         3 . The method of  claim 1 , where the bond is monolithic. 
     
     
         4 . The method of  claim 1 , wherein the fiber tape includes continuous uni-directional fiberglass fibers. 
     
     
         5 . The method of  claim 1 , wherein the fiber tape is a polyethylene tape. 
     
     
         6 . The method of  claim 1 , further comprising the step of wrapping a second fiber tape over a surface of the first fiber tape. 
     
     
         7 . The method of  claim 6  where in the first fiber tape and second fiber tape are comprised of polyethylene material. 
     
     
         8 . The method of  claim 6  further comprising the step of wrapping a film over the surface of the second fiber tape. 
     
     
         9 . The method of  claim 8  wherein the film is a UV protective film. 
     
     
         10 . The method of  claim 1 , wherein the thermoplastic pipe is made of polyethylene. 
     
     
         11 . A method for manufacturing a reinforced pipe system for transporting a fluid, comprising:
 cooling a high density polyethylene pipe;   wrapping a fiber tape on a surface of the high density polyethylene pipe, said fiber tape having continuous taut fibers;   warming the fiber tape and high density polyethylene pipe using a heat source;   embedding the taut fibers into the high density polyethylene pipe as the high density polyethylene pipe is warmed; and   melting the fiber tape and the high density polyethylene pipe to create a bond.   
     
     
         12 . The method of  claim 11 , where the bond is a homogenous. 
     
     
         13 . The method of  claim 11 , where the bond is monolithic. 
     
     
         14 . The method of  claim 11 , wherein the fiber tape includes continuous uni-directional fiberglass fibers. 
     
     
         15 . The method of  claim 11 , wherein the fiber tape is a polyethylene tape. 
     
     
         16 . A method for manufacturing a reinforced pipe system for transporting a fluid, comprising:
 cooling a thermoplastic pipe;   wrapping a fiber tape on a surface of the thermoplastic pipe, said fiber tape having continuous taut fibers;   securing ends of the fiber tape to the ends of the thermoplastic pipe using a first heat source;   warming the fiber tape and thermoplastic pipe using a second heat source;   embedding the taut fibers into the thermoplastic pipe as the thermoplastic pipe is warmed; and   bonding the fiber tape to the thermoplastic pipe as the fiber tape and thermoplastic pipe reach a thermal equilibrium.   
     
     
         17 . The method of  claim 16 , wherein the fiber tape includes continuous uni-directional fiberglass fibers. 
     
     
         18 . The method of  claim 16 , wherein the fiber tape is a polyethylene tape. 
     
     
         19 . The method of  claim 16 , wherein the thermoplastic pipe is made of polyethylene. 
     
     
         20 . The method of  claim 16 , further comprising the step of wrapping a second fiber tape over a surface of the first fiber tape.