Overview - EN ISO 21787:2006 (Globe valves, thermoplastics)
EN ISO 21787:2006 specifies requirements for the design, functional characteristics, manufacture and testing of globe valves made from thermoplastic materials intended for isolating and control service in industrial pipe systems. The standard covers hand- and power-operated globe valves with nominal sizes DN 10 to DN 150 and pressure ratings PN 6, PN 10, PN 16 and Class 150, with an intended service temperature range of −40 °C to +120 °C and a design life of 25 years. It also defines connection, marking, documentation and testing requirements.
Key topics and technical requirements
- Scope of application: Valves for industrial pipe systems irrespective of field or conveyed fluid (includes water supply, drainage and sewerage).
- Design & function: Requirements for full-bore or reduced-bore designs, bidirectional or unidirectional obturation, stem sealing (stuffing box or self-sealing elements) and blow-out proof stems.
- Materials & pressure/temperature rating: Thermoplastic materials and rating factors for allowable operating pressures across the specified temperature range.
- Sizes and classes: DN 10, 15, 20, 25, 40, 50, 65, 80, 100, 125, 150; PN 6/10/16 and Class 150.
- Testing: Specifies initial type tests and pressure/functional tests (see referenced test standards such as EN 12266-1 and ISO pressure/fatigue tests listed in normative references).
- Marking, traceability and documentation: Mandatory marking, operation instructions and traceability requirements; supports conformity assessment under EU Directive 97/23/EC (PED) within the standard’s scope.
- Service life: Design assumption and test regime consistent with a 25-year lifetime.
Practical applications
- Specifying and procuring thermoplastic globe valves for industrial piping projects where corrosion resistance, chemical compatibility and lightweight construction are required.
- Use in industries and systems that demand predictable pressure/temperature performance up to +120 °C and long-term reliability (25-year design life).
- Suitable for pipeline segments requiring isolation and throttling: process lines, water treatment, drainage, chemical handling systems (subject to compatibility checks).
Who should use this standard
- Valve manufacturers designing thermoplastic globe valves.
- Piping engineers and specifiers writing procurement and project specifications.
- Quality & testing laboratories performing type and production tests.
- Procurement and compliance teams assessing conformity to EU PED and national standards.
Related standards
Relevant references cited by EN ISO 21787:2006 include (non‑exhaustive):
- EN 12266-1 (valve testing - pressure tests and acceptance)
- EN 12570 (sizing operating element)
- EN 558 series (face-to-face dimensions)
- ISO 10931, ISO 12162, ISO 15493 / ISO 15494 (thermoplastic material/system specifications)
Using EN ISO 21787 helps ensure consistent performance, traceability and regulatory alignment when selecting or manufacturing thermoplastic globe valves for industrial piping systems.
