scope:

The purpose of this study is to: 1) identify appropriate literature on polymeric piping and components and 2) compare international standards for polymeric piping and components. The information gained from this study is expected to assist the ASME through the PVRC in establishing a basis for the development of uniform industry guidelines for the design, fabrication, testing, and installation of plastic piping products for chemical service applications in pressurized systems. The scope of this report covers thermoplastic and reinforced thermosetting resin (RTR) piping systems and component.

The primary standards addressed in this report for thermoplastic and thermosetting plastic piping include: U.S.: ASME B31.1, ASME B31.3, ASME BPV Code Section X, ASME Standard RTP-1, AWWA C950, and ASTM standards; British BS7159; German Deutscher Verbandfuer Achweisstechnick (DVS); and International ISO standards.

Key aspects considered for comparing the various standards are: allowable material properties, design criteria for internal pressure, design criteria for external pressure, pipe support, flange design, flexibility analysis, bonding/jointing and inspection criteria.

The report considers:

• Physical property data of thermoplastic and thermosetting plastic materials (e.g., stress and creep-related properties of elevated temperatures).

• Variable safety factors for service design, derating, and for the operating environment.

• Cyclic stress conditions (BS7159 presents some stress intensification factors for glass reinforced polyester material).

• Criteria for flexibility design/analysis and cyclic stress reduction.

• Additional guidance on bonding and joining.

• Bond quality factors for various types of plastic piping joints.

• Inspection requirements and acceptance criteria.

Many recommendations are woven throughout the report and for convenience they are summarized in an Appendix. Publication of this document - WRC Bulletin No. 415 was sponsored by the Committee on Polymers for Pressure Components of the Pressure Vessel Research Council.