Reinforced Thermoplastic Composite Pipe for High Pressure Gas/Liquid Artic Pipelines - A Viable Alternative to Steel?
Authors: Catha Steve , Ekelund Aron , Stonesifer Randy , Kanninen Mel , Ausman Earle 
Published: December 2011

The costs of manufacturing, shipping, in-field joining, inspecting, coating and cathodically protecting steel pipe having sufficient toughness at sub zero temperatures are limiting factors in new Arctic pipeline construction. This paper proposes that consideration be given to the Smart Pipe®, a recently perfected, self-monitoring thermoplastic composite pipe that has been proven for high pressure crude oil and natural gas rehabilitation, for consideration in Arctic conditions. Use of a reinforced thermoplastic composite pipe -- a material that does not corrode -- can be a viable alternative from a cost perspective alone. But, added to a significant cost advantage are the capabilities of this new class of pipe in regard to accommodating frost heaving and thaw settlement, subsidence and seismic ground movements, and large temperature ranges. The Smart Pipe® specifically offers the potential for much easier installations, superior performance, and substantially lower acquisition, installation, and maintenance costs. This paper describes the concept, reviews the successful installations that have been made, describes key R&D progress in areas that reflect its superior Arctic usage, and suggests a process by which it can be adapted and substantiated for use in new construction in the Arctic.

Introduction

The costs and availability of steel pipe having sufficient toughness at the lower end of the design temperatures in the Arctic, along with the substantial costs of shipping, in-field joining and weld inspections, and of coating and cathodically protecting these pipes, are handicapping new Arctic pipeline construction. A viable alternative is a recently perfected concept that has now been proven for crude oil and natural gas pipeline rehabilitation. This new concept offers the potential for much easier installations, superior performance, and substantially lower acquisition, installation and maintenance costs. This is a reinforced thermoplastic composite pipe known as the Smart Pipe®; a non-corroding, self-monitoring pipe that can be simultaneously manufactured and deployed in a factory that moves along the right of way and that is capable of transporting oil and natural gas at very high pressures.

There are many significant attributes that Smart Pipe® offers for Arctic applications, including:the use of a transportable factory that is moved along the right of way - with limited environmental impact, even in difficult terrain -- to simultaneously manufacture and deploy a pipe that does not corrode,built-in 24/7 pipeline condition monitoring capabilities that can instantaneously detect and accurately locate mechanical impacts, leaks and ground movements,minimal coefficients of thermal expansion that can minimize or possibly eliminate the need for expansion loops, andsubstantially lower costs, possibly as low as 50% of the cost of a steel pipeline that is designed for the same operating conditions.

Further, ice road wintertime installations can be efficiently made without the need for special equipment associated with steel pipelines (e.g., bending machines and other heavy equipment) that would need to be transported to the job site. The Smart Pipe® is tolerant of subsidence and seismic ground movements, in addition to being able to accommodate frost heaving and thaw settlement. Finally, because the technology and the materials are generally of U.S. origin, they will be more readily available and attainable at lower shipping costs.