Pressure regulators

Pressure regulators from Festo

Pressure regulators are used in pneumatic applications to set and keep the pressure level of a machine constant. In many applications, the pressure of compressors, which supply compressed air in the range of 10...16 bar, is too high, so it has to be reduced with the help of pressure regulators. Excessive pressure leads to higher wear of the application or unnecessarily high energy costs, while with insufficient pressure the required speed or force performance is not reached. This results in fluctuations in quality and faulty results.

Operating mode of pressure regulators

The incoming compressed air that flows from the input of the pressure regulator to the valve seat is the primary pressure or input pressure. The pressure regulator ensures that the compressed air, as it flows through the valve, is at the required secondary pressure, also called output pressure. This is regulated in line with the specific requirements by adjusting the rotary knob. When the rotary knob is turned, this moves a spring that exerts a force on the upper side of the regulating diaphragm, which in turn pushes up or down. The valve tappet is actuated and the valve bore opens. When the secondary pressure drops, the spring force on the diaphragm is greater than the counteracting output pressure. This pushes the valve tappet further down, which increases the valve opening and causes the output pressure to rise again.

Pressure regulators of the MS-B series

Our new MS-B series features the second-generation pressure regulator MS-LR-B, which is our attractively priced, technical polymer series. It has a grid dimension of 25, 40 or 62 mm and is easy to operate thanks to the modern polymer materials. The air pressure is regulated and locked by a rotary knob, while integrated primary and secondary exhausting with reverse flow behaviour ensures stable control behaviour. Pressure regulator MS-LR-B is available with pressure gauge or G1/8 adapter ("A8").

MS basic series

Pressure regulators of the MS series

Our "one MS worldwide" offers a wide range of pressure regulators. From an integrated return flow function and secondary exhausting as standard to high flow rate performance and very good control characteristics, the MS series offers the right product for every application. It is available in four sizes, with mechanical pressure gauge or alternatively with pressure sensor with and without display. In addition, all pressure regulators in the MS series can be installed in service unit combinations thanks to the simple modular system of the MS series. The pressure regulators can also be configured for use in potentially explosive areas of zones 1, 2, 21 and 22 as well as with UL approval.

MS series

Pressure regulators of the D series

The D series includes the pressure regulator LR-DB with the following pressure range: 7 bar output pressure and 10 bar input pressure. Another characteristic is the high flow rate performance with good pressure stability. It is available in one size with a flow rate of up to approx. 1,300 l/min.

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Pressure regulator individual devices

Irrespective of the series, you can also obtain individual devices from us that are suitable for more sensitive applications. For example, precision pressure regulators LRP and LRPS are the ideal choice when a pressure hysteresis of 0.02 bar is required. Both regulators enable the pressure to be precisely adjusted both in static and dynamic applications. Operating pressure fluctuations are compensated for. They are available in sizes 40 mm with a ⅛" connecting thread and 300 l/min standard nominal flow rate as well as 50 mm with a ¼" connecting thread and 2,300 l/min standard nominal flow rate.

Electrically actuated pressure regulator PREL with a pressure regulation range of up to 40 bar is ideally suited for high-pressure applications. The output pressure of electric pressure regulator PREL is detected by proportional-pressure regulator VPPL using an integrated pressure sensor and compared internally with the setpoint. In case of deviations, the VPPL controls the regulator of the PREL until the output pressure reaches the setpoint value. A soft-start function is integrated as standard in the PREL. In addition, there are pressure gauge connections on the front and back of the pressure regulator.

Individual devices

Pressure regulators

Pressure regulators come in many sizes and types. This category of pressure regulators (pressure reducing valves) are designed to be installed with air supply units, and are suitable for supplying machines or plants with conditioned compressed air. The advantage of a compressed air pressure regulator is that it ensures that the pressure of the compressor is reduced and remains at the set pressure (bar). The pressure gauge shows how high or low the working pressure is set. A pressure regulator is often used to keep the compressed air system under constant pressure and low (re) pressure without restricting the operation of the machine, but with a large gain in energy consumption. These pressure regulators (pressure reducing valves) can be switched as a battery and provide different air pressure (bar) in a machine or plant. Inline pressure regulators are also available from Festo and are more suitable for supplying one compressed air duct or application with a lower pressure. These can be found in the valves category.

Buying the right compressed air pressure regulator

A pressure regulator (pressure reducing valve) is used to limit the operating pressure of a system while compensating for small pressure fluctuations. Basically, the compressor and compressed air system always supplies compressed air at a higher pressure than required. There many types of pressure regulators, and there are two primary operating principles: the direct-operated diaphragm regulator and, for larger sizes (maxi), the pilot-operated piston control valve.

Direct-operated diaphragm regulator

In this pressure regulator, force is applied to a diaphragm by means of a main spring. This force can be adjusted by manually turning a knob on the pressure regulator. In the centre of the diaphragm is a sealing element, which seals the front of the piston of the pressure regulator due to the selected force applied by the main spring and the spring of the pressure regulator piston.

When the main spring is set, the regulator piston is pushed down and the lower sealing seat opens, while the front of the regulator piston continues to close the sealing element in the diaphragm. The flow from the supply to the exhaust port, for pressurising and venting the system, is thus open. In this position, small pressure fluctuations of compressed air and associated changes in flow rate at the lower seal seat are compensated by a slight movement of the control piston.

When the pressure on the working port is increased to a level higher than the selected working pressure, a force is exerted on the underside of the membrane that pushes the diaphragm upwards and clearly compresses the main spring. The spring pushes up the piston of the pressure regulator and completely seals the lower seal seat, but no longer reaches the seal seat in the diaphragm.

Air escapes through the sealing element in the diaphragm and through an outlet port on the pressure regulator housing. This process is called secondary venting. Secondary venting If the pressure on the consumer's working port increases through the value selected on the regulator, this "excess pressure" can also be vented through the pressure regulator.

Pilot-operated pressure regulator (pressure reducing valves)

The general function is the same as that of the direct-operated pressure reducer (pressure regulator). Here, however, the function of the diaphragm is taken over by a piston, i.e. the pilot piston. In the initial position, the pilot piston and regulator piston are in the upper end positions, so the lower seal seat is closed. Now when air flows from the supply port into the valve, it initially flows around the lower part of the control piston. The air flows into the regulator through a small connecting hole about 0.1 mm in diameter, and thus to the top of the control piston. The resulting force eventually opens the lower seal seat, allowing flow to the working port.

Components for pressure control

A pressure regulator exists in the MS, D and MS-Basic series. different materials, different design and in any connection (e.g. 3 8, 1/4, ...). Suitable for compressed air as a medium in low pressure, we do not offer a solution for water pipe, liquid, or pressure regulator hydraulics. The size of the pneumatic pressure regulator does not determine the higher pressure (bar), but the passage. Correctly sizing the various components is important for your application. This calculation is easy to make in our Engineering Tool: combinations of supply units. The valve you use best will be suggested according to your parameters and compressed air connectors.

Using a high pressure regulator with compressed air tools can cause a few potential issues:

1. Inadequate Pressure: If the regulator is not set to the appropriate pressure range for the specific compressed air tool being used, it can result in inadequate pressure reaching the tool. This can lead to reduced performance or inefficient operation of the tool, affecting its effectiveness in completing the intended task.

2. Over-Pressure: On the other hand, if the regulator is set too high, it can cause over-pressurization of the compressed air tool. This can potentially damage the tool or its components, leading to malfunctions, leaks, or even catastrophic failures. Over-pressurization can also pose a safety risk to the operator and those nearby.

3. Inconsistent Operation: If the regulator does not maintain a steady and consistent pressure output, it can result in inconsistent operation of the compressed air tool. Fluctuating pressure can affect the tool's performance, accuracy, and reliability, leading to unpredictable results or subpar outcomes.

4. Increased Wear and Tear: Operating compressed air tools at incorrect pressures due to improper regulator settings can increase wear and tear on the tool. This can lead to accelerated deterioration of internal components, decreased lifespan of the tool, and the need for more frequent repairs or replacements.

Festo Core Range: Always in stock

With the Festo Core Range, you can choose from an extensive portfolio and benefit from high-quality components at particularly attractive prices.