PV/EL
Pressure and 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
- available in a special design with lifting device
- maintenance-friendly design
Function and Description
The PV/EL type PROTEGO® valve is a highly developed combined pressure and vacuum relief valve. It is primarily used as a device for relieving pressure and vacuum in tanks, containers, and process engineering equipment. The valve offers reliable protection against unallowable overpressure and underpressure. Product loss close to the set pressure is avoided and unallowable product entry is prevented.
The device will start to open as soon as the set pressure is reached and only requires 10% overpressure to 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 characteristic 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 or vacuum (MAWP or MAWV) of the tank and still safely vent the required mass flow. The opening characteristic is the same for pressure and vacuum relief.
Due to the highly developed manufacturing technology, the tank pressure is maintained up to the set pressure with a tightness that is far superior to the conventional standard. This feature is achieved by valve seats made of high quality stainless steel and with precisely lapped valve pallets (1) or with an air cushion seal (2) in conjunction with high quality FEP diaphragm. The valve pallets are also available with a PTFE seal to prevent the valve pallet from sticking when sticky products are used, and they enable the use of corrosive substances. After the overpressure is released or the vacuum is balanced, the valve re-seats and provides a tight seal.
The optimized fluid dynamic design of the valve body and valve pallet is a result of many years of research, resulting in a stable operation of the valve pallet, optimized performance, and reduced product losses.
Dimensions
To select the nominal size (DN), use the flow capacity chart on the following page
| DN | 50 / 2" | 50 / 2" | 80 / 3" | 80 / 3" |
| Set pressure | ≤ +60 mbar | > +60 mbar | ≤ +60 mbar | > +60 mbar |
| Set pressure | ≤ +24.1 inch W.C. | > +24.1 inch W.C. | ≤ +24.1 inch W.C. | > +24.1 inch W.C. |
| a | 308 / 12.13 | 443 / 17.44 | 308 / 12.13 | 443 / 17.44 |
| b | 108 / 4.25 | 108 / 4.25 | 108 / 4.25 | 108 / 4.25 |
| c | 165 / 6.50 | 165 / 6.50 | 167 / 6.57 | 167 / 6.57 |
| d | 218 / 8.58 | 218 / 8.58 | 218 / 8.58 | 218 / 8.58 |
Material selection for housing
| Design | B | C |
| Housing | Steel | Stainless Steel |
| Heating jacket (PV / EL-H-...) | Steel | Stainless Steel |
| Valve seat | Stainless Steel | Stainless Steel |
| Weather hood | Steel | Stainless Steel |
| Protective mesh screen | Stainless Steel | Stainless Steel |
Material selection for pressure valve pallet
| Design | A | B | C | D |
| Pressure range [mbar] [inch W.C.] | +2.0 up to +3.5 +0.8 up to +1.4 | >+3.5 up to +14 >+1.4 up to +5.6 | >+14 up to +210 >+5.6 up to +84 | >+14 up to +210 >+5.6 up to +84 |
| Valve pallet | Aluminium | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | FEP | FEP | Metal to Metal | PTFE |
Material selection for vacuum valve pallet
| Design | A | B | C | D |
| Pressure range [mbar] [inch W.C.] | -3.5 up to -5.0 -1.4 up to -2.0 | <5.0 up to -14 <-2.0 up to -5.6 | <-14 up to -35 <-5.6 up to -14 | <-14 up to -35 <-5.6 up to -14 |
| Valve pallet | Aluminium | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | FEP | FEP | Metal to Metal | PTFE |
Flange connection type
| EN 1092-1; Form B1 |
| ASME B16.5 CL 150 R.F. |
Design Types and Specifications
The valve pallets are weight-loaded. At set pressures greate than 60 mbar (24.1 inch W.C.), an elongated construction is used.
There are two different designs:
Pressure/vacuum relief valve in basic design | PV/EL - – |
Pressure/vacuum relief valve with heating jacket | PV/EL - H |
Additional special devices available upon request.
Any combination of vacuum and pressure levels can be set for the valve. When the difference between the pressure and vacuum exceeds 150 mbar / 60.2 inch W.C., special valve pallets are used.
Settings
| Pressure: | +2.0 mbar | +210 mbar | |
| +0.8 inch W.C. | +84 inch W.C. | ||
| Vacuum: | -14 mbar | -35 mbar | |
| -5.6 inch W.C. | -14 inch W.C. | ||
| Vacuum: | -3.5 mbar | -14 mbar | |
| -1.4 inch W.C. | -5.6 inch W.C. |
Higher and lower settings upon request.
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”.
