Features
Function and Description
Pressure or Backflow Protection in Venting or Exhaust Lines
The PROTEGO® In-Line Valve DV/ZT is a state-of-the-art 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. . 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 provides protection from product Product Includes equipment, protective systems, devices, components and combinations of these. entry into the system. For structural reasons, the lower valve pallet Valve pallet Valve pallet is the generic term for the assembly that rests on the valve seat. is one size smaller than the upper valve pallet.
Full Lift Technology
The device Device A device is a pipe component that influences the media flow by opening, closing, or partially shutting off the flow channel or by dividing or mixing the media flow. 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. 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 above the conventional standard.
Custom Materials
This feature is ensured by valve seats made of high quality stainless steel and with individually 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 valve pallets from sticking when sticky products are used and to enable the use of corrosive fluids. 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 stable operation of the valve pallet, optimized performance, and reduced product 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), please use the flow capacity chart on the following page
| DN | 40 / 1½“ | 50 / 2" | 80 / 3" | 100 / 4" | 150 / 6" |
| a | 280 / 11.02 | 280 / 11.02 | 340 / 13.39 | 390 / 15.35 | 520 / 20.47 |
| b | 270 / 10.63 | 270 / 10.63 | 290 / 11.42 | 355 / 13.98 | 425 / 16.73 |
| c | 210 / 8.27 | 210 / 8.27 | 280 / 11.02 | 310 / 12.20 | 390 / 15.35 |
Dimensions in mm / inches
Larger sizes upon request
Dimensions for pressure and vacuum relief valve with heating jacket upon request
Material selection for housing
| Design | A | B |
| 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. | Steel | Stainless Steel |
| Heating jacket (DV / ZT-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 |
| Gasket | PTFE | PTFE |
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 upper 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 ±60 >±5.6 up to ±24 | ±14 up to ±60 >±5.6 up to ±24 |
| Valve pallet | Aluminium | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | FEP | FEP | Metal to Metal | PTFE |
Special materials upon request
For higher set pressure refer to type DV/ZT-F.
Material selection for lower valve pallet
| Design | A | B | C | D | E | F |
| 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 ±50 ±14 up to ±20 | ±14 up to ±35 ±5.6 up to ±14 | ±35 up to ±50 ±14 up to ±20 |
| Valve pallet | Aluminium | Stainless Steel | Stainless Steel | Stainless Steel | Stainless Steel | Stainless Steel |
| Sealing | FEP | FEP | Metal to Metal | Metal to Metal | PTFE | PTFE |
Special materials and lower set vacuum Set vacuum Internal negative gauge pressure at which a vacuum valve first opens. 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 valve pallets are weight loaded. Higher set pressures are achieved by using spring Spring A spring is a spiral of wire which returns to its original shape after it is pressed or pulled. loaded type DV/ZT-FTwo different designs are available:
Additional special devices available upon request
Within piping systems the influence of backpressure has to be considered in deciding the set pressure and opening characteristics. For special design solutions (e.g. partial load operation) the valve can be supplied with standard valve pallets (with proportional opening function).
Settings
| Upper valve pallet: | ±2.0 mbar | ±60 mbar |
| ±0.8 inch W.C. | ±24 inch W.C. | |
| Lower valve pallet: | ±3.5 mbar | ±50 mbar |
| ±1.4 inch W.C. | ±20 inch W.C. |
For higher set pressure refer to type DV/ZT-F.
Lower set vacuum 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”.
