VN-A-PCPM
Pressure/Vacuum Relief ValvePilot-operated diaphragm valve
Features
Permanent Magnets
controlled by corrosion-resistant control valve (
pilot valve
Pilot valve
The pilot valve is an assembly of a pilot operated valve, which is mounted on the main valve and is used to control the main valve.
), low-temperature-resistant permanent magnet
Pop-Open Characteristic
from the lowest pressure increase up to full
lift
Lift
Lift is the actual travel of the valve pallet from the main valve out of the closed position.
Extreme Tightness
resulting in lowest possible
product
Product
Includes equipment, protective systems, devices, components and combinations of these.
losses and reduced environmental pollution
10% Technology
for minimum pressure increase up to full lift
Optimal Pressure Maintenance
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.
close to opening pressure for optimum pressure
maintenance
Maintenance
Combination of all technical and administrative actions, including supervision actions, intended to maintain or restore a unit in working order.
in the system
Flow Capacity
optimized flow capacity
High Durability
protection of the main valve control
diaphragm
Diaphragm
A diaphragm is a thin layer of material, which has a large surface area.
from low temperatures – high durability
Used in Explosion Hazardous Areas
Low Temperature
designed for use at low temperatures
Condensate Drainage
automatic condensate drain
Field Test Kit
field test and kit connection possible upon request
Function and Description
Combined Pressure and Vacuum Relief Valve
The PROTEGO® VN-A-PCPM pilot-operated diaphragm valve is a highly developed valve for pressure and
vacuum
Vacuum
Vacuum is the pressure in an enclosed space that is lower than the ambient pressure.
relief. It is primarily used as a safety
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.
for out-breathing in tanks, containers, 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.
. It provides protection against unallowable
overpressure
Overpressure
Overpressure refers to an increase in pressure in a system or vessel above the normal operating pressure.
and prevents the intake of air and unallowable product vapor loss up to the set pressure.The valve can also be used as an in-breathing valve where the main valve is directly controlled when it is exposed to a vacuum, i.e., it functions as a weight-loaded diaphragm valve. It is ideally suitable for both
atmospheric conditions
Atmospheric conditions
Atmospheric conditions are pressures from 80 kPa till 110 kPa and
temperatures from -20°C up to +60°C.
and for use in low temperatures.
Extreme tightness
The main valve (2) is controlled by a pilot valve (1). The pilot valve is controlled by the
tank pressure
Tank pressure
Tank pressure is the pressure within a tank.
. The tank substance does not continuously flow through the pilot. The set pressure is adjusted on the pilot valve by a corrosion-resistant and low-temperature- resistant permanent magnet.
As the
operating pressure
Operating pressure
Operating pressure is the pressure existing at normal operating conditions within the system being protected.
increases, the closing force at the main valve also increases; i.e., the valve tightness increases until the set pressure is reached to prevent leakage. After the valve responds, it immediately opens completely without any significant increase in pressure (pop-open characteristic), and the nominal volumetric flow is released through a fully open valve. If this is exceeded, the pressure increase follows the volume flow (Δp/V̇ curve). From set pressure to full capacity (fully open valve), the pressure increase is 100% in case of vacuum venting/in-breathing function.
advanced manufacturing technology
The tank pressure is maintained up to the set pressure with a tightness that is above the normal standards due to our state-of-the art manufacturing. This feature is ensured by valve seats made of high quality stainless steel with precisely lapped valve pallets. After the overpressure is released or the vacuum is balanced, the valve re-seats and provides a tight
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.
.
Product Data and Features
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 charts on the following pages
| DN1 | DN2 | a | b | c | d | e | f | g |
| 50 / 2" | 50 / 2" | 175 / 6.89 | 175 / 6.89 | 170 / 6.69 | 360 / 14.17 | 838 / 32.99 | 205 / 8.07 | 371 / 14.61 |
| 50 / 2" | 80 / 3" | 175 / 6.89 | 175 / 6.89 | 170 / 6.69 | 360 / 14.17 | 853 / 33.58 | 205 / 8.07 | 386 / 15.20 |
| 80 / 3" | 80 / 3" | 200 / 7.87 | 200 / 7.87 | 205 / 8.07 | 360 / 14.17 | 878 / 34.57 | 205 / 8.07 | 411 / 16.18 |
| 80 / 3" | 100 / 4" | 200 / 7.87 | 200 / 7.87 | 205 / 8.07 | 360 / 14.17 | 888 / 34.96 | 205 / 8.07 | 421 / 16.57 |
| 100 / 4" | 100 / 4" | 225 / 8.86 | 225 / 8.86 | 250 / 9.84 | 360 / 14.17 | 913 / 35.94 | 205 / 8.07 | 446 / 17.56 |
| 100 / 4" | 150 / 6" | 225 / 8.86 | 225 / 8.86 | 250 / 9.84 | 360 / 14.17 | 923 / 36.34 | 205 / 8.07 | 456 / 17.95 |
| 150 / 6" | 150 / 6" | 300 / 11.81 | 250 / 9.84 | 335 / 13.19 | 500 / 19.69 | 1025 / 40.35 | 275 / 10.83 | 531 / 20.91 |
| 150 / 6" | 200 / 8" | 300 / 11.81 | 250 / 9.84 | 335 / 13.19 | 500 / 19.69 | 1045 / 41.14 | 275 / 10.83 | 551 / 21.69 |
| 200 / 8" | 200 / 8" | 375 / 14.77 | 300 / 11.81 | 410 / 16.14 | 630 / 24.80 | 1237 / 48.70 | 340 / 13.39 | 638 / 25.12 |
| 200 / 8" | 250 / 10" | 375 / 14.77 | 300 / 11.81 | 410 / 16.14 | 630 / 24.80 | 1188 / 46.77 | 340 / 13.39 | 668 / 26.30 |
| 250 / 10" | 250 / 10" | 425 / 16.73 | 350 / 13.78 | 500 / 19.69 | 790 / 31.10 | 1278 / 50.31 | 420 / 16.54 | 738 / 29.05 |
| 250 / 10" | 300 / 12" | 425 / 16.73 | 350 / 13.78 | 500 / 19.69 | 790 / 31.10 | 1298 / 51.10 | 420 / 16.54 | 758 / 29.84 |
| 300 / 12" | 300 / 12" | 500 / 19.69 | 400 / 15.75 | 570 / 22.44 | 920 / 36.22 | 1389 / 54.58 | 485 / 19.09 | 831 / 32.72 |
| 300 / 12" | 350 / 14" | 500 / 19.69 | 400 / 15.75 | 570 / 22.44 | 920 / 36.22 | 1409 / 55.47 | 485 / 19.09 | 851 / 33.50 |
| 300 / 12" | 400 / 16" | 500 / 19.69 | 400 / 15.75 | 570 / 22.44 | 920 / 36.22 | 1429 / 56.26 | 485 / 19.09 | 871 / 34.29 |
Dimensions in mm / inches
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 | Stainless Steel | LTCS* (Low Temperature Carbon 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 - housing | PTFE | PTFE | PTFE |
| Sealing – valve disc | metal - to - metal | metal - to - metal | metal - to - metal |
| Housing diaphragm | Stainless Steel | Stainless Steel | Stainless Steel |
| Pilot lines | Stainless Steel | Stainless Steel | Stainless Steel |
| Pilot housing | Aluminium | Aluminium/ Stainless Steel | Aluminium/ Stainless Steel |
| Pilot diaphragm | FEP | FEP | FEP |
* Special materials upon request
Flange connection type
| EN 1092-1; Form B1 |
| ASME B16.5 CL 150 R.F. |
Other types upon request
Coefficient of Discharge
| DN1 | 50 / 2" | 50 / 2" | 80 / 3" | 80 / 3" | 100 / 4" | 100 / 4" | 150 / 6" | 150 / 6" | 200 / 8" | 200 / 8" | 250 / 10" | 250 / 10" | 300 / 12" | 300 / 12" | 300 / 12" |
| DN2 | 50 / 2" | 80 / 3" | 80 / 3" | 100 / 4" | 100 / 4" | 150 / 6" | 150 / 6" | 200 / 8" | 200 / 8" | 250 / 10" | 250 / 10" | 300 / 12" | 300 / 12" | 350 / 14" | 400 / 16" |
| d0 | 54 / 2.13 | 54 / 2.13 | 83 / 3.27 | 83 / 3.27 | 108 / 4.25 | 108 / 4.25 | 160 / 6.30 | 160 / 6.30 | 208 / 8.19 | 208 / 8.19 | 262 / 10.31 | 262 / 10.31 | 310 / 12.20 | 310 / 12.20 | 310 / 12.20 |
| K | 0.57 | 0.75 | 0.63 | 0.71 | 0.60 | 0.75 | 0.64 | 0.78 | 0.63 | 0.76 | 0.62 | 0.73 | 0.63 | 0.68 | 0.74 |
DN1 = size inlet
DN2 = size outlet
d0 = orifice diameter(mm / inches)
K = coefficient of discharge
Basic design of
pressure/vacuum relief valve
Pressure/vacuum relief valve
Pressure/vacuum relief valve is an umbrella term that includes pressure or vacuum relief valve as well as pressure and vacuum relief valve.
with a pilot valve
Basic pressure/vacuum relief valve with a pilot valveVN-A-PCPM
Additional special devices available upon request.
* It is recommended that an external control line is to be provided with direct connection to the tank.
Settings
| Pressure: | +20 mbar | +1034 mbar |
| Vacuum: | -2.2 mbar | -7 mbar |
| -0.88 inch W.C. | -2.8 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”.
Applications