VN-VU
Vacuum Relief Valve
- 10% technology for minimum pressure increase up to full lift
- extreme tightness, resulting in lowest possible product losses and reduced environmental pollution
- set pressure close to opening pressure for optimum pressure maintenance in the system
- high flow capacity
- valve pallet is guided inside the housing to protect against harsh weather conditions
- can be used in explosion hazardous areas
- automatic condensate drain
- best technology for API tanks
Function and Description
The VN-VU type PROTEGO® valve is a highly developed vacuum relief valve with excellent flow performance. It is primarily used as a device for relieving vacuum in tanks, containers, and process engineering equipment. The valve offers reliable protection against vacuum and prevents in-breathing of air close to the set pressure.
The device will start to open as soon as the set pressure is reached and only requires 10% overpressure to reach full lift. Continuous investments in and a commitment to research and development have allowed PROTEGO® to develop a low pressure valve which has the same opening characteristics as a high pressure safety relief valve.
This “full lift type” technology allows the valve to be set at just 10% below the maximum allowable working pressure of the tank and still safely vent the required mass flow.
Due to our highly developed manufacturing technology, the tank pressure is maintained up to set pressure with a tightness that is far superior to the conventional standard. This feature is achieved by valve seat made of high quality stainless steel and with precisely lapped valve pallets (1). After the vacuum is released, the valve reseats and provides a tight seal again.
Dimensions
| DN | 400 / 16" |
| a | 690 / 27.17 |
| b | 470 / 18.50 |
| c | 750 / 29.53 |
| d | 435 / 17.13 |
| e | 1086 / 42.76 |
Material selection for housing
| Design | A | C | D |
| Housing | Aluminium | Stainless Steel | Low Temperature Carbon Steel |
| Valve seat | Stainless Steel | Stainless Steel | Stainless Steel |
| Protective grating | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | PTFE | PTFE | PTFE |
Material selection for vacuum valve pallet
| Design | C | D | E | F |
| vacuum range [mbar] [inch W.C.] | <-4,4 <-1.76 | < >=-4,4 up to -7,6 < >=-1.76 up to 3.04 | < >=-7,6 up to -13,2 < >=-3.04 up to -5.28 | < >=-13,2 < >=-5.28 |
| Max. Back pressure [mbar] [inch W.C.] | 245 98 | 1690 676 | 580 232 | 2000 800 |
| Valve pallet | Aluminium, thin | Aluminium, thick | Stainless Steel, thin | Stainless Steel, thick |
| Sealing | Metal to Metal | Metal to Metal | Metal to Metal | Metal to Metal |
Flange connection type
| EN 1092-1; Form B1 |
| ASME B16.5 CL 150 R.F. |
Design Types and Specifications
The valve pallet is weight-loaded.
Vacuum valve in basic design | VN-VU |
Additional special devices available upon request.
Settings
| Vacuum: | -2.6 mbar | -25 mbar | |
| -10 inch W.C. |
Flow Capacity Chart
The flow capacity charts have been determined with a calibrated and TÜV certified flow capacity test rig. Volume flow V in (m³/h) and CFH refer to the standard reference conditions of air ISO 6358 (20°C, 1bar). For conversion to other densities and temperatures refer to Sec. 1: “Technical Fundamentals”.
