Designed and manufactured in Badalona since 1962
Pressure reducing valves
They keep the downstream pressure constant even when the inlet pressure or the demand changes, without auxiliary power. Eight piston, diaphragm, or bellows models for steam, water, compressed air, gases, and oil.
- SizesDN8 to DN150
- Inlet pressureup to 40 barg
- Outlet pressure0.01 to 20 barg
- Temperatureup to 220 °C
Not sure which model you need? Call 933 720 888 or email valfonta@valfonta.com.
Find your reducing valve
Fluid
Outlet pressure
Size
- In-house design and manufacturing in Badalona
- ATEX II 2 GD marking across the entire range
- No auxiliary power: they run on the process fluid itself
- Genuine spare parts for each model
Pressure reducing valve models
Filter with the search tool in the header or switch to the comparison table. Each product page includes the complete specifications, the exploded view, installation, and PDFs.
Piston reducing valves
For water, oil, compressed air, and inert gases. Not suitable for steam, except the VD, which now handles steam up to 200 °C.
Piston · 316L stainless
PRV20
Compact piston reducing valve, threaded from ¼″ to ¾″.
Outlet
0.2 to 20 barg
Max. inlet
40 barg
Size
DN8 to DN20
Temperature
−20 to 150 °C with Viton gaskets
Choose it if you need high outlet pressures, up to 20 barg, in small water, oil, compressed air, or gas lines.
Piston · 316L stainless
PRV30
Piston reducing valve in 316L stainless, threaded or with EN and ANSI flanges.
Outlet
0.5 to 12 barg
Max. inlet
25 barg
Size
DN15 to DN25
Temperature
80 °C 125–150 °C with EPDM or Viton
Choose it if you want a simple stainless reducing valve for water, oil, compressed air, or inert gases.
New: steam up to 200 °C
VD
Reducing valve with a 3-point guided piston, in bronze, WCB steel, or CF3M stainless.
Outlet
1.5 to 16 barg
Max. inlet
40 barg
Size
DN15 to DN100
Temperature
steam up to 200 °C −20 to 200 °C with AFLAS gaskets
Choose it if you need high flow rates of steam up to 200 °C, water, fuel oil, compressed air, or inert gases, up to DN100.
Diaphragm reducing valves
The diaphragm makes it possible to regulate very low outlet pressures, from 10 mbar, and to work with steam using a sensing line and diaphragm protection.
Diaphragm · low pressure
PRV45
Diaphragm reducing valve in 316L stainless for very low outlet pressures.
Outlet
0.01 to 8 barg
Max. inlet
16 barg
Size
DN15 to DN25
Temperature
steam up to 150 °C −10 to 150 °C with Viton gaskets
Choose it if you need to regulate gases, compressed air, nitrogen, or steam from 10 mbar.
Diaphragm
M2
Direct-acting diaphragm reducing valve, with EN or ANSI flanges or threaded.
Outlet
0.02 to 10 barg
Max. inlet
40 barg 25 from DN65
Size
DN15 to DN100
Temperature
steam up to 180 °C with condensate pot
Choose it if you need low outlet pressures, from 0.02 barg, in medium and large sizes.
Diaphragm · high flow
M1
Self-operated diaphragm reducing valve, up to DN150 and a Kv of 240 m³/h.
Outlet
0.1 to 15 barg
Max. inlet
40 barg 25 from DN65
Size
DN15 to DN150
Temperature
steam up to 220 °C with condensate pot
Choose it if you regulate steam or hot liquids at high flow rates, up to DN150.
Bellows reducing valves
Designed for steam: the PRV44 works up to 210 °C and the M2F up to 200 °C without a condensate pot.
Bellows · steam
PRV44
Bellows-balanced reducing valve, made entirely of 316L stainless steel.
Outlet
0.5 to 12 barg
Max. inlet
25 barg
Size
DN15 to DN25
Temperature
steam up to 210 °C
Choose it if you regulate steam or hot fluids in small lines.
Bellows · no water seal pot
M2F
Bellows-balanced reducing valve that works with steam without a condensate pot.
Outlet
1 to 10 barg
Max. inlet
25 barg
Size
DN15 to DN50
Temperature
steam up to 200 °C
Choose it if you regulate steam up to 200 °C and want to do without the water seal pot.
* PRV30: 80 °C with NBR gaskets; from 125 to 150 °C with EPDM or Viton. Data from the Valfonta general reducing valve catalog (2025); the M2F is not included in it, and its data come from its datasheet. On the M1 and M2, the maximum inlet pressure drops to 25 barg from DN65.
No standard model matches these filters. Valfonta adapts models and designs custom valves: tell us about your application in the form or see the custom design service.
How it works and where it is installed
A reducing valve receives the fluid at a high, variable pressure and delivers it downstream at a lower, stable pressure, the one you set with the adjusting screw. It protects equipment that cannot withstand the line pressure and keeps the process running under the same conditions at all times.
Valfonta reducing valves are self-operated: a spring opposes the outlet pressure, and that balance moves the plug, with no air, electricity, or control system. Compressing the spring raises the outlet pressure.
They are installed in the line, ahead of the consumer they protect, with shutoff valves, a strainer, inlet and outlet pressure gauges, and a safety valve downstream. See how to install a reducing valve and how to adjust it.
- Shutoff and bypass valves
- Strainer
- Inlet pressure gauge
- Reducing valve
- Safety valve
- Outlet pressure gauge
Piston, diaphragm, or bellows: what changes
They all regulate the same way; what changes is the element that senses the outlet pressure, and that determines which fluids and pressures each one is suited for.
Piston
A piston receives the outlet pressure and opposes the spring.
- Water, oil, compressed air, and inert gases.
- Inlet pressures up to 40 barg (PRV20 and VD).
- Not suitable for steam, except the VD (up to 200 °C).
Diaphragm
A large-area diaphragm senses the outlet pressure, which provides greater sensitivity.
- Very low outlet pressures: from 10 mbar (PRV45) or 0.02 barg (M2).
- Steam up to 180–220 °C with a sensing line and condensate pot.
- Up to DN150 (M1).
More detail in the comparison of piston and diaphragm reducing valves and in what the bellows adds to tightness.
Applications
- Steam networksReduction to the pressure required by each consumer with the M1, the PRV44, or the M2F.
- Compressed airFrom line pressure to each machine’s working pressure, with any model in the range.
- Water and fire protectionDistribution networks, sprinklers, and wastewater with the VD and the M2.
- Laboratories and sanitary plantsSmall 316L stainless steel lines with the PRV20 and the PRV30.
- Low-pressure gasesFine regulation from 10 mbar with the PRV45 or from 0.02 barg with the M2.
- High flow ratesUp to DN150 and a Kv of 240 m³/h with the M1.
Standards and certificates
PED 2014/68/EU
Quality system certified to Module D1. Depending on size, pressure, and fluid, some models fall under Article 4.3, without CE marking: each product page indicates this.
ATEX II 2 GD
For Zones 1 and 21 (and 2 and 22), within the temperature class corresponding to the fluid temperature.
ISO 9001:2015
Design, manufacture, and sale of globe control valves for process control.
Download Valfonta’s certificates.
Frequently asked questions about pressure reducing valves
What is a pressure reducing valve?
It is a valve that reduces the pressure of a fluid and keeps it stable downstream, even when the inlet pressure or the demand varies. Valfonta valves are self-operated: they run on the energy of the fluid itself, with no air or electricity.
Which reducing valve do I need for steam?
For steam, the suitable models are the PRV44 (up to 210 °C), the PRV45 (up to 150 °C), the VD (up to 200 °C), the M1 (up to 220 °C), the M2 (up to 180 °C), and the M2F (up to 200 °C without a condensate pot). The PRV20 and the PRV30 are not suitable for steam.
What is the lowest outlet pressure that can be regulated?
The PRV45 regulates from 0.01 barg (10 mbar) and the M2 from 0.02 barg. For higher outlet pressures, the PRV20 reaches 20 barg.
Do they need auxiliary power or a control system?
No. The adjusting spring and the outlet pressure balance the plug. If you need to control the pressure from a control system, see the C1 control valve with pneumatic actuator.
Does a reducing valve replace a safety valve?
No. The reducing valve regulates the outlet pressure but does not protect against overpressure: if the installation requires it, also install a safety valve downstream.
What information does Valfonta need to prepare a quote?
The fluid and its temperature, the inlet pressure, the desired outlet pressure, the maximum and minimum flow rate, and the connection type. With that, we will recommend the model, size, spring range, and gaskets.
Technical guides on reducing valves
Other families: Pressure relief valves · Control valves · Custom design · Safety valves
Request a quote for a reducing valve
Give us your installation details and we will recommend the right model, size, spring range, and gaskets.
- Fluid and operating temperature
- Inlet pressure and desired outlet pressure
- Maximum and minimum flow rate
- Connection type (threaded or flanged)
You can also call 933 720 888.
