Overview
ISO 16137:2006 - Industrial valves - Check valves of thermoplastics materials defines requirements for the design, functional characteristics, manufacture and testing of thermoplastic check valves used to allow flow in one direction and prevent backflow in industrial pipe systems. The standard covers valves made from common thermoplastic materials (ABS, PE, PP, PVC‑C, PVC‑U, PVDF), a working temperature range from −40 °C to +120 °C, and a design lifetime of 25 years. It applies across DN sizes DN 8 to DN 600 and pressure classes PN 6, PN 10, PN 16, PN 25 and Class 150/300.
Key topics
- Function and design requirements
- One‑way flow (automatic opening by hydraulic force; reverse flow closure; springs permissible).
- Suitability for specific installation positions (operation depends on orientation).
- Materials
- Body/bonnet materials limited to thermoplastics listed in the standard; trim and internal parts selected by the manufacturer but required to meet mechanical integrity and testing.
- Pressure/temperature rating
- Uses MRS values (ISO 12162) and introduces a rating factor (f) to relate PMA (allowable maximum operating pressure) to PN or Class for the valve design and lifetime.
- Manufacturer must declare p/t ratings for each valve type and material; Table 1 provides minimum rating factors and allowable temperatures.
- Dimensions and end connections
- Defines acceptable end connections (flanged, wafer, butt‑fusion, spigot, socket fusion, threaded, union, etc.) and references face‑to‑face dimensions for flanged systems (EN 558).
- Manufacture, testing and documentation
- Specifies initial type tests, pressure/functional testing and documentation of test results, declaration of compliance, marking and storage/transport requirements.
Applications
ISO 16137 is intended for the specification, production and assessment of thermoplastic check valves used in:
- Industrial piping systems (chemical, water treatment, process plants)
- Water supply, drainage and sewerage systems (general industrial use)
- Any application requiring corrosion‑resistant, lightweight non‑metallic check valves where backflow prevention is needed
Who uses this standard
- Valve manufacturers and designers specifying thermoplastic check valves
- Pipeline and process engineers selecting valve materials, PN/DN ratings and end connections
- Quality and compliance teams performing type tests, documentation and certification
- Procurement and plant operators requiring lifetime and pressure/temperature data
Related standards
Standards referenced by ISO 16137 include ISO 15493, ISO 15494, ISO 10931, ISO 12162 (MRS and p/t ratings), EN 558 (face‑to‑face dimensions) and EN 12266‑1 (valve testing), among others - important for detailed material, dimensional and test-method requirements.
Keywords: ISO 16137, thermoplastic check valve, check valves, pressure‑temperature rating, PN, DN, PVDF, PVC‑U, valve testing, backflow prevention.
