L51789 Recommended Practice for Sour Service Piping

Abstract

Existing industry standards do not adequately address all the issues related to construction and operation of pipelines to transport fluids containing both liquid water and hydrogen sulfide (H2 S), commonly called wet sour service or sour-service applications. The lack of industry standardization for sour service is significant because some commercially available line pipe, fittings and flanges are susceptible to failure when exposed to sour service. The failures that can occur are due to damage of carbon steel as a result of the corrosion reaction between H2 S and carbon steel. Operators of sour-service systems have developed company-specific or project-specific practices and specifications for design, construction, operation and maintenance of those systems. One result of company-specific and/or project-specific specifications is a lack of standardization in sour-service line pipe, fittings and flanges. The lack of standardization in sour-service piping components results in additional costs for initial construction, modification and maintenance of sour-service systems. The objective of this project was to develop recommended practices that a knowledgeable user can apply to the specification of line pipe, fittings and flanges for use in construction of pipelines and piping systems to transport fluids containing both liquid water and H2S. Development of recommended practices for construction, modification and maintenance of sour-service systems was outside the scope of this project. This report includes a discussion of the current understanding of broad issues relating to sour-service pipelines. This discussion is a summary of the more important issues rather than a critical review of all related literature on the subject of sour service. This report includes recommended specification criteria for line pipe, fittings and flanges in expository format. These criteria provide guidance for preparation of the specifications in commercial language for sour-service line pipe, fittings and flanges. These criteria should allow users to modify existing specifications for ordinary-service piping components to specifications suitable for sour service. This project included a survey of LPRSC members and producers of line pipe, fittings and flanges recommended by committee members. The goal of these surveys was to collect current information about the range of member practices and products readily available from surveyed producers.