Overview
EN 1074-2:2000/A1:2004 is a CEN amendment addressing valves for water supply - Part 2: Isolating valves. The amendment corrects the test procedure in Annex C (C.2: "Test method for the operation of valves") and clarifies the verification sequence for isolating (shut-off) valves. It focuses on ensuring fitness for purpose through practical verification tests that confirm seat tightness and operational torque under hydrostatic conditions.
Key Topics and Requirements
- Scope: Applies to verification tests for isolating valves used in water supply systems; the amendment revises the C.2 test method.
- Test procedure (corrected C.2) - key steps include:
- Fit a blanking plate with a vent valve to the outlet flange and connect the inlet to a hydrostatic pressure source.
- Partially open the obturator and the vent valve; fully fill the valve body and vent all air.
- Close the obturator and apply a torque equal to MOT (the specified test torque).
- Raise pressure to PFA (the specified test pressure) and maintain it for at least one minute.
- Check seat tightness while holding pressure.
- Open and close the valve while ensuring the running torque during operation does not exceed MOT; record the maximum torque observed.
- Repeat the entire test from the opposite side (bi‑directional verification).
- Operational checks: Confirms both leak-tightness at the seat and that operating torque remains within acceptable limits during pressurized cycling.
- Practical notes included: The test procedure highlights that a large volume of water is evacuated through the vent valve during opening.
Applications and Users
This standard and its corrected test method are essential for:
- Valve manufacturers - type testing, quality control, and design verification for isolating valves.
- Independent test laboratories - performing hydrostatic and operational torque tests to certify compliance.
- Water utilities and network operators - specifying procurement and acceptance criteria to ensure reliable isolation under pressure.
- Specifiers and regulators - incorporating fitness-for-purpose requirements into technical specifications and approvals.
- Installers and maintenance teams - understanding test expectations for commissioning and troubleshooting.
Related Standards
- EN 1074 series (other parts covering valves for water supply) and documents produced by CEN/TC 69 (Industrial valves).
- National adoptions (e.g., SIST EN 1074-2:2001/A1:2004) reflect mandatory implementation timelines across CEN member bodies.
Keywords: EN 1074-2:2000/A1:2004, valves for water supply, isolating valves, fitness for purpose, verification tests, test procedure, hydrostatic pressure, seat tightness, MOT, PFA.