5.3 水力特征 Hydraulic characteristics
5.3.1 General
The tests described are type tests (laboratory tests), not quality control tests carried out during manufacture.
This clause gives a test method for measuring the flow rate and the cross-flow between the hot and cold water supply for a given pressure.
5.3.2 Test apparatus for tapware intended for Type 1 water supply systems
5.3.2.1 General
This comprises:
— two supply circuits (hot water and cold water inlets) (see Figure 11);
— test circuit (see Figure 12).
5.3.2.2 Supply circuits type 1
Key
1 pressure regulator
2 piping
3 flow rate measurement
4 cold water inlet
5 hot water inlet
6 supply circuits
7 sample to be tested
Figure 11 — Supply circuits
Each circuit comprises of:
— device (1) for obtaining the required pressures;
— piping (2) of appropriate cross-section for the flow to be obtained;
— device (3) for measuring the flow rate.
5.3.2.3 Test circuit Type 1
Each inlet to the tap or mixing valve comprises:
a) piping made from a rigid metal tube, of diameter and length in accordance with the dimensions in Table 9;
b) reinforced flexible hoses, 500 mm long with a minimum internal diameter equal to that of the rigid metal tube, with a device for connecting to the tapware;
c) device for measuring the flow rates (measurement accuracy ± 2 %);
d) device to connect the piping to the supply circuit;
e) pressure take-off tee for measuring the pressure at the inlets of the mixing valves (measurement accuracy ± 1 %);
f) system for recording the test conditions and results is appropriate.
Dimensions in millimetres
Key
1 connection to supply circuit
2 metal tube
3 pressure taping
4 connection
5 hot water inlet
6 cold water inlet
7 mixing device
Figure 12 — Test circuits for tapware intended for Type 1 water supply systems
Table 9 — Dimensions of pipework
5.3.2.4 Pressure take-off tees
The pressure take-off tees shall be the individual type or the annular slit type (see Annex A).
5.3.2.5 Mounting of single taps intended for Type 1 water supply systems
Only the cold water supply shown in Figure 11 is used for the tests.
5.3.2.6 Mounting of mixing valves intended for Type 1 water supply systems
Depending on the type of mixing valve, one of the mounting arrangements shown in Figure 13 shall be used:
Key
1 flexible hose
Figure 13 — Mounting of mixing valves
5.3.2.7 Test apparatus for tapware intended for Type 2 supply systems
A test rig as shown in Figure 14 shall be used.
Key
1 pressure take-off tee
5 stop valve
2 control valve
6 centres to suit tap assemblies
3 flow meter
7 pressure gauge (Manometer)
4 cold supply
8 1020 mm of water [0,01 MPa (0,1 bar)]
Figure 14 — Flow rate test apparatus for taps intended for type 2 supply systems
NOTE The tube ends are straight, without burrs and inserted to the full depth of dimension A in the pressure take-off tee.
5.3.3 Principle of the flow test
Measurements are carried out on tapware intended for Type 1 supply systems - as supplied e.g. with any accessory fitted.
Measurements are carried out on tapware intended for Type 2 supply systems - with any detachable check valve element, flow rate regulator, etc. removed.
The test is carried out with cold water:
— at a dynamic pressure of (0,3 ± 0,02) MPa ((3,0 ± 0,2) bar) for tapware intended for Type 1 supply systems;
— at a dynamic pressure of (0,01 ± 0,002) MPa ((0,1 ± 0,02) bar) for tapware intended for Type 2 supply systems.
Mixing valves are tested in the hot, cold and mid blend positions with cold water.
The least favourable values are recorded.
The tapware is to be operated following the manufacturer’s instructions.
5.3.4 Requirements
The flow rate when fully open and supplied under the conditions specified in 5.3.3 shall comply with the requirements specified in Table 10.
Table 10 — Minimum flow rates and test pressures according to application
5.3.5 Cross flow between hot and cold water
5.3.5.1 Principle
If the mixing device is placed upstream of the solenoid valve, a device to prevent cross flow between hot and cold water is mandatory.
If the mixing device is placed downstream of the solenoid valve, a device to prevent cross flow between hot and cold water is not mandatory.
Such devices may be incorporated into the mixing valve itself, or supplied separately.
5.3.5.2 Procedure
The test is conducted using cold water.
Connect one inlet of the mixing valve to the test circuit.
With the outlet orifice open and obturator closed, apply a water pressure of (0,4 ± 0,02) MPa ((4 ± 0,2) bar) to the mixing valve for (60 ± 5) s for the full operating range of the temperature adjustment device.
Repeat the test with the other water inlet of the mixing valve connected to the test circuit.
5.3.5.3 Requirements
For the duration of the test, there shall be no leakage or seepage at the outlet or at the end of the unconnected inlet.