YRD iris valves are designed to regulate the flow of air and measure its flow rate in circular air channels.
Structurally, YRD valves are an iris diaphragm installed in a housing with round connecting pipes. The valve body is marked with an easy-to-read adjustment scale and connection fittings are installed to measure the pressure drop across the valve. By setting the position of the diaphragm lobes according to the risks of the scale and measuring the pressure on the valve with a differential pressure gauge, you can determine the flow rate of air passing through the valve with great accuracy. YRD air valves are operated manually.
The valves remain functional and can be operated regardless of their spatial orientation. The use of iris valves can significantly simplify the process of setting up ventilation systems.The valve body and control plates are made of galvanized steel sheet. The pipes of the housing are provided with rubber seals, which ensures tightness of the connection to the air ducts.
Technical specifications
| Model | Ød, мм | ØD, мм | ØL, мм | ØA, мм | ØB, мм | Weight, кг |
| YRD 100 | 99 | 165 | 110 | 30 | 32 | 0,5 |
| YRD 125 | 124 | 188 | 110 | 30 | 32 | 0,7 |
| YRD 160 | 159 | 230 | 110 | 30 | 35 | 0,9 |
| YRD 200 | 199 | 285 | 110 | 30 | 42 | 1,4 |
| YRD 250 | 249 | 335 | 132 | 40 | 42 | 2,3 |
The YRD iris valve provides accurate measurements at all points in the network, including points near local resistances such as T-shaped tees and bends, turns, bends, and points in front of air distribution devices. Depending on the required measurement accuracy δL, the iris valve should be installed with the minimum distance recommendations Lmin shown in the table.
Recommended distances between valve and local resistance
| Local resistance | L, min | |
| δL=±7% | δL=±10% | |
|
≥1d | ≥1d |
|
≥4d | ≥2d |
|
≥2d | ≥2d |
|
≥2d | ≥2d |
Noise characteristics
The octave sound power level and the corrected sound power level are determined by the formulas:
Lwокт = Lp10A + Kокт
LwA = Lp10A + 4
где: Lwокт, dB – octave sound power level;
Lp10A, dB(А) – sound level (corrected sound pressure level for a room with an equivalent sound absorption area of 10 m²) is determined by the diagram;
Kокт – correction factor;
LwA, dB(А) – adjusted sound power level.
| Model | Correction factor Kокт, дБ | |||||||
| 63 | 125 | 250 | 500 | 1 000 | 2 000 | 4 000 | 8 000 | |
| YRD 100 | 25 | 21 | 16 | 9 | 4 | -6 | -12 | -25 |
| YRD 125 | 17 | 17 | 13 | 7 | 1 | -4 | -6 | -17 |
| YRD 160 | 19 | 18 | 14 | 6 | -1 | -6 | -13 | -25 |
| YRD 200 | 20 | 17 | 12 | 5 | -2 | -5 | -14 | -26 |
| YRD 250 | 16 | 12 | 8 | 3 | 1 | -4 | -17 | -32 |
Recommended prices
Toffee valve YRD100 - 5 057,40
Toffee valve YRD125 - 5 343,67
Toffee valve YRD160 - 5 534,51
Toffee valve YRD200 - 6 202,47
Toffee valve YRD250 - 9 351,41