Overview
ISO 16136:2006 - Industrial valves - Butterfly valves of thermoplastics materials - defines requirements for the design, functional characteristics, manufacture and testing of thermoplastic butterfly valves intended for isolating and control service in industrial pipe systems. The standard covers valves sized DN 15 through DN 600 and rated for PN 6, PN 10, PN 16 and Class 150, with a design service temperature range of −40 °C to +120 °C and a reference lifetime of 25 years. It applies to hand- or power-operated valves regardless of industry or conveyed fluid.
Key Topics and Requirements
- Materials: Acceptable body/cover materials include ABS, PE, PP, PVC‑C, PVC‑U and PVDF. Trim and sealing materials are selected by the manufacturer but must meet the standard’s test requirements.
- Design features:
- Soft-seat obturation; seat may be full bore (≥ 90% of DN) or reduced bore (manufacturer must declare pressure loss factor).
- Disc rotated 90° on a fixed, blow‑out‑proof shaft.
- Shaft sealing by self‑sealing elements; visible disc orientation and positive disc-to-shaft connection.
- End connections: Supports butt fusion, spigot, socket (electrofusion/heated tool/cement), flanged, wafer, threaded and union ends, among others.
- Pressure/temperature rating:
- Valve PMA (maximum allowable pressure) is determined from the shell material rating and valve design using a rating factor f.
- Formula: PMA = f × PN (bar) or PMA = f × Class (psi). Minimum f values and allowable temperatures are specified for a 25‑year lifetime.
- Testing and conformity:
- Initial type tests and performance tests are required (torque, fatigue, pressure tests, etc.) and documented as part of compliance.
- Requirements for marking, storage, transportation, and a declaration of compliance are specified.
Applications and Users
ISO 16136 is practical for:
- Valve manufacturers designing and certifying thermoplastic butterfly valves.
- Piping designers, process and mechanical engineers specifying valves for chemical, water, drainage, wastewater and other industrial systems.
- Procurement and quality teams requiring documented test results and declared p/t ratings.
- Test laboratories and conformity assessment bodies performing type and routine testing.
Use cases include corrosive process lines, water treatment, chemical handling, and any application where lightweight, corrosion‑resistant butterfly valves are preferred.
Related Standards
Key referenced documents include:
Keywords: ISO 16136, butterfly valves, thermoplastics, industrial valves, pressure/temperature rating, DN sizes, PN, Class 150, PVDF, PVC‑U.
