Features
Function and Description
Combined Pressure and Vacuum Relief Valve
The VD/SV Type PROTEGO® valve is a highly developed pressure and vacuum relief valve Pressure and vacuum relief valve A pressure and vacuum relief valve is a pressure equalization valve for impermissible pressure and vacuum in a closed system. with excellent flow performance. Typically, the valve is installed in the in-breathing and out-breathing lines of tanks, vessels, and process equipment Equipment Machines, appliances, fixed or mobile devices, control parts and accessories, and warning and prevention systems, whether separate or combined, intended for the generation, transfer, storage, measurement, control, and conversion of energy, and for the processing of materials, which have their own potential source of ignition and may cause an explosion. to protect against unallowable overpressure Overpressure Overpressure refers to an increase in pressure in a system or vessel above the normal operating pressure. and underpressure. The valve prevents emission losses almost up to the set pressure Set pressure Set pressure is the gauge pressure at the device inlet at which the relief device is set to start opening under service conditions. and prevents air intake almost up to the set vacuum Set vacuum Internal negative gauge pressure at which a vacuum valve first opens. .
Full Lift Technology
The device will start to open as soon as the set pressure is reached and only requires 10% overpressure to full lift Lift Lift is the actual travel of the valve pallet from the main valve out of the closed position. . Continuous investments in and a commitment to research and development have allowed PROTEGO® to develop a low pressure Pressure (gauge pressure) Pressure for which the value is equal to the algebraic difference between the absolute pressure and the atmospheric 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 Vacuum Vacuum is the pressure in an enclosed space that is lower than the ambient pressure. ( MAWP Maximum allowable working pressure (MAWP) Maximum gauge pressure permissible at the top of a completed vessel in its normal operating position at the designated coincident temperature specified for that pressure. or MAWV) of the tank and still safely vent the required mass flow. The opening characteristic is the same for pressure and vacuum relief.
Advanced Manufacturing Technology
Due to our highly developed manufacturing technology, the tank pressure Tank pressure Tank pressure is the pressure within a tank. is maintained up to 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 Seal A seal prevents or limits unwanted transfer of product from one container to another. Seal is used as superordinate term for all types of sealing elements. (2) in conjunction with high quality FEP diaphragm Diaphragm A diaphragm is a thin layer of material, which has a large surface area. . The valve pallets are also available with a PTFE seal to prevent the them from sticking when sticky products are used and to 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 Valve pallet Valve pallet is the generic term for the assembly that rests on the valve seat. is a result of many years of research, resulting in stable operation of the valve pallet, optimized performance, and reduced product Product Includes equipment, protective systems, devices, components and combinations of these. losses.
Dimensions
To select the nominal size Nominal size The nominal size is an alphanumeric designation of size for components in a piping system, used for reference purposes, comprising the letters DN followed by a dimensionless integer that is indirectly related to the physical size of the bore or outside diameter of the connections, expessed in millimeters. (DN), use the flow capacity chart on the following page
| DN | 50 / 2" | 80 / 3" | 100 / 4" | 150 / 6" | 200 / 8" | 250 / 10" | 300 / 12" |
| a | 490 / 19.29 | 660 / 25.98 | 755 / 29.72 | 1020 / 40.16 | 1210 / 47.64 | 1210 / 47.64 | 1275 / 50.20 |
| a | 1110 / 43.70 ( adjusted set pressure Adjusted set pressure Adjusted set pressure is the pressure at which a valve opens on a test bench. >+400 mbar) | 1300 / 51.18 (adjusted set pressure >+300 mbar) | 1300 / 51.18 (adjusted set pressure >+200 mbar) | ||||
| b | 355 / 13.98 | 450 / 17.72 | 550 / 21.65 | 790 / 31.10 | 900 / 35.43 | 1030 / 40.55 | 1030 / 40.55 |
| c | 200 / 7.87 | 295 / 11.61 | 295 / 11.61 | 475 / 18.70 | 560 / 22.05 | 660 / 25.98 | 660 / 25.98 |
Dimensions in mm / inches
Dimensions of pressure and vacuum relief valves with heating jacket upon request
Material selection for housing
| Design | A | B | C |
| Housing Housing A housing is a solid shell, which surrounds a content, either protecting the content from external influences, or protecting the environment from the content. | Aluminium | Steel | Stainless Steel |
| Heating jacket (VD/SV-PF-H-...) | – | Steel | Stainless Steel |
| Valve seat Valve seat The valve seat is a component on which the valve pallet rests when the valve is closed. | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | PTFE | PTFE | PTFE |
| Weather hood Weather hood A weather hood is a cover to protect the internal components of a device from environmental influences. | Stainless Steel | Stainless Steel | Stainless Steel |
Option: Housing with ECTFE- lining Lining Protective plastic lining with a defined minimum/maximum thickness to protect against aggressive mixtures (e.g., acid).
Special materials upon request
Material selection for pressure valve pallet
| Design | A |
| Pressure range [mbar] [inch W.C.] | >+60 up to +500 >+24 up to +200 |
| Valve pallet | Stainless Steel |
| Sealing | Metal to Metal |
| Spring Spring A spring is a spiral of wire which returns to its original shape after it is pressed or pulled. | Stainless Steel |
Special material as well as higher set pressure upon request
Material selection for vacuum 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 -35 <-5.6 up to -14 | <-35 up to -60 <-14 up to -24 |
| Valve pallet | Aluminium | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | FEP | FEP | Metal to Metal | Metal to Metal |
Special material as well as higher vacuum upon request
Flange connection type
| EN 1092-1; Form B1 |
| ASME B16.5 CL 150 R.F. |
other types upon request
Design Types and Specifications
The pressure valve pallet is spring loaded, the vacuum valve pallet weight loaded. Lower set pressures for the pressure side are achieved through weight loaded type VD/SV.Two different designs are available:
Additional special devices available upon request
With these valves, it is generally important to consider the
back pressure
Back pressure
The back pressure is the sum of built-up back pressure and superimposed back pressure.
.
Settings
| Pressure: | +60 mbar | +500 mbar |
| +0.8 inch W.C. | +24 inch W.C. | |
| Vacuum: | -14 mbar | -60 mbar |
| -5.6 inch W.C. | -24 inch W.C. | |
| Vacuum: by set pressure up to +150 mbar / +60 inch W.C. | -2.0 mbar | -14 mbar |
| -0.8 inch W.C. | -5.6 inch W.C. |
Higher or 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”.
