EN 13433:2007 – Devices to prevent pollution by backflow of potable water – Mechanical disconnector, direct actuated – Family G, type A

1 Scope
This European Standard specifies, the dimensional, the physico-chemical, the design, the hydraulic, the mechanical and the acoustic characteristics of mechanical disconnector, direct actuated Family G, type A.
This European Standard is applicable to mechanical disconnector direct actuated in nominal sizes DN 8 up to DN 250, intended to prevent the return of water having lost its original sanitary and drinking qualities (called “polluted water” in this European Standard), into the potable water distribution system whenever the pressure of the latter is temporarily lower than in the polluted circuit.
This European Standard covers the mechanical disconnector direct actuated of PN 10 that are capable of working without modification or adjustment:
 at any pressure up to 1 MPa (10 bar);
 with any pressure variation up to 1 MPa (10 bar);
 in permanent duty at a limit temperature of 65 °C and 90 °C for 1 h maximum.
It specifies also the test methods and requirements for verifying these characteristics, the marking and the presentation at delivery.
2 Normative references
The following referenced documents are indispensable for the application of this European Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN 806-1:2000, Specifications for installations inside buildings conveying water for human consumption — Part 1: General
EN 1092-1, Flanges and their joints — Circular flanges for pipes, valves, fittings and accessories, PN designated — Part 1: Steel flanges
EN 1092-2, Flanges and their joints — Circular flanges for pipes, valves, fittings and accessories, PN designated — Part 2: Cast iron flanges
EN 1717:2000, Protection against pollution of potable water in water installations and general requirements of devices to prevent pollution by backflow
EN 13959, Anti-pollution check valves DN 6 to DN 250 inclusive family E, type A, B, C and D
EN ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads — Part 1: Dimensions,tolerances and designation (ISO 228-1:2000)
EN ISO 3822-1, Acoustics — Laboratory tests on noise emission from appliances and equipment used in water supply installations — Part 1: Method of measurement (ISO 3822-1:1999)
EN ISO 3822-3:1997, Acoustics — Laboratory tests on noise emission from appliances and equipment used
in water supply installations — Part 3: Mounting and operating conditions for in-line valves and appliances (ISO 3822-3:1984)
EN ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in circular crosssection conduits running full — Part 1: General principles and requirements (ISO 5167-1:2003)
3 Terms and definitions
For the purposes of this European Standard, the terms and definitions given in EN 1717:2000, EN 806-1:2000 and the following apply.
3.1
mechanical disconnector, hydraulic actuated — Family G, type A
specific characteristics of this device called “GA”, (see Figure 1) are as follows:
two pressure zones in flow position: upstream and downstream;
three zones in drain position (zero-flow): upstream, intermediate and downstream. The upstream spring oaded obturator with discharge system and the downstream check valve separate the intermediate zone from the upstream and downstream zone;
flow position is achieved at a pressure p f ≤ p s + 50 kPa (0,5 bar);
EN 13433:2007 – Devices to prevent pollution by backflow of potable water – Mechanical disconnector, direct actuated – Family G, type A