Original
By certification 
Pneumatic Diaphragm Noise reduction Single Seat Control Valve
There are three reasons (methods) for the noise generated by the control valve:
Mechanical noise, liquid dynamic noise, and gas dynamic noise. When the pressure difference between the front and rear of the valve is large, the valve is vented, and cavitation occurs, there will be different levels of excessive noise. When the noise exceeds the standard, a low-noise control valve must be selected.
Pneumatic diaphragm low noise single seat control valve ordering instructions:
When ordering, please provide the following information:
1. Name, model and purpose of regulating valve
2. Nominal diameter (mm), nominal pressure (MPa), working temperature and range
3. Upstream pressure, downstream pressure
4. medium and status, medium flow
5. Bonnet Type
6. Fail open or fail close, instrument air (air source) pressure
7. Material requirements for valve body and valve trim
Accessory Requirements
8. Electric-pneumatic valve positioner, air filter pressure reducer, solenoid valve, position retaining valve, valve position transmitter, (top-mounted) handwheel, etc.
9. Valve body flange standard (ASME, DIN, GOST, GB etc.)
10. Length of valve body structure (face to face)
Body Face To Face Lenth:
| PN16/ class150 |
DN | 15 | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 125 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 | 550 | 600 |
| NPS | 1/2" | 3/4" | 1" | 1-1/4" | 1-1/2" | 2" | 2-1/2" | 3" | 4" | 5" | 6" | 8" | 10" | 12" | 14" | 16" | 18" | 20" | 22" | 24" | |
| lenth | 184 | 184 | 184 | 222 | 222 | 254 | 276 | 298 | 352 | 403 | 451 | 543 | 673 | 737 | 787 | 1016 | 978 | 978 | 1067 | 1295 |
http://www.lozosevalve.com/
