NACE SP0304

Abstract

Scope: General This standard defines the process necessary to design, install, and operate a thermoplastic-lined oilfield pipeline. The design process includes an assessment of the service conditions, materials, chemical compatibilities of liner materials with any service fluids and additives, pipeline geometry, and risk analysis. The installation process includes site surveys, pipeline preparation, insertion, termination, pressure testing, reburial, and safety. Operation of a lined system must take into consideration the service fluids, materials of construction, safety and environment, commissioning, normal operation, depressuring, and upset conditions, and inspection for liner integrity. This standard is not intended to replace detailed procedures specific to the particular installation method developed by installers, nor is it intended to replace pipeline operating instructions developed by operators. It is intended to set a standard for performance within the scope of these procedures and instructions. This standard is not intended to apply in all cases relating to the subject. Unpredictable circumstances may negate the usefulness of this standard in specific instances. In plastic-lined steel, the corrosion/erosion resistance of the inner plastic pipe and the strength/mechanical durability of the metal case are both exploited. This allows for design pressures equal to those of the host pipe. The subject liners are installed in the field after the steel pipeline is completed. The liners may be installed in new pipelines, or in existing pipelines for rehabilitation purposes. The liners consist of a free-standing thermoplastic pipe that is inserted into the existing steel host pipe and is designed in such a way that the liner pipe does not require the use of a third material to fill any gaps between the liner and the host pipe. The liner pipe is designed to remain in close contact with the host pipe during operation. This standard is not applicable to thermoplastic pipes (often referred to as liners), that are inserted into a host pipe, but are required to contain the pressure of the service without the host pipe.