Liang Yu, Akshay Ponda, Dane Chang
Papers # 2018 Las-Vegas
Following the development of US shale oil and gas production since 2007, the demand for thermoplastic pipes with better corrosion resistance, and lower installation and operation cost than carbon steel pipe, has been growing significantly. Nylon 12 has been qualified for hydrocarbon transportation in offshore flexible pipes and for natural gas distribution pipes. It maintains its mechanical properties well when contacting hydrocarbons, natural gas condensate and refined fuels. A unique method of co-extruding Nylon 12 and Polyethylene with a high temperature tie-bond layer in-between to form a fully bonded tri-layer pipe is developed. This tri-layer PA-PERT pipe has the combined advantages of Nylon 12’s resistance to hydrocarbon and the cost-effectiveness of Polyethylene. For low pressure applications (<240 psi), the tri-layer PA-PERT pipe is designed with PE layer wall thickness of DR 9 without any other reinforcement layer. An environmental application factor of 0.5 is not needed because the Nylon 12 inner layer protects the PE structural layer outside. The pipe is coextruded in diameters ranging from 2 inch to 6 inch nominal size. For higher pressure applications (300 psi to 2000 psi), this tri-layer PA-PERT pipe can be reinforced with Aramid fiber in the same diameter range. This paper presents the design, manufacture and qualification test of the co-extruded PAPERT pipe for transportation of crude oil, produced water, brine and natural gases.
This paper presents the design, manufacture and qualification of PA-PERT co-extruded pipe as gathering lines for oil and gas transportation. A high temperature tie-bond resin was developed successfully to bond PA12 and PERT layers at temperature up to 180F. Patent pending co-extrusion tooling enables high quality production of PA-PERT pipes. Extensive qualification tests have been conducted with successful results. The nonreinforced pipe can be used for low-pressure applications while the Aramid fiber reinforced pipe is used for higher pressure applications. Both non-reinforced and reinforced PAPERT pipes have been deployed in many oil and gas fields over US with an excellent track record.
