Pressure Control Valves

Pressure limiting or bypass valves

Coolants that consist of oils or emulsions are usually used for metal machining applications. The precisely regulated coolant pressure at the tool ensures that the lubricating coolant achieves the best results on the valuable workpiece even at the highest cutting speeds. Our valve series offer reproducible tolerances and dimensional accuracy as well as the highest surface quality of the workpieces in series production.

Metal chips – even from the deepest blind holes – can only be rinsed out safely with precisely regulated coolant pressure. Perfect cooling of the tool cutting edges is assured, and premature tool wear is avoided.

Series SPB and (3)-HPB pressure control valves ensure precise pressure control regardless of the amount of coolant. Coolant requirement on the tool can fluctuate enormously, depending on the machining cycle in which the tool is located – for example, during the tool change cycle, switching the tool on and off, feeds, etc. Excess coolant is returned to the coolant tank via the valve without recognizable pressure fluctuations. Pressure regulating valves supply the system with a precise coolant pressure, but they also protect the pipes and pumps against damage caused by overpressure due to their operating principle. Valves of this series are referred to as pressure limiting valves (DBV). Since the valves are installed in the return of the coolant supply, they are also called bypass valves.

The pressure control for Series (3)-HPB valves is done manually; thus, only one pressure level can be selected at a time. The valves are operated electro-pneumatically - the set pressure is switched on and off via a power supply (24 Volts, for example).

The pressure control is active when the voltage is switched on, and the valve is open when the voltage is switched off. When the valve is switched off, all of the coolant flows into the tank; the function is called a pressure-minimized circulation circuit. This circulation switch is always suitable for soft start of the positive displacement pumps, or for changing of tools and workpieces if no coolant is required.

We offer two-pressure control as an accessory module. This module can be retrofitted to any valve to allow the user to switch between two system pressures.

The bypass valves from Series SPB operate electro-pneumatically and are controlled by a setpoint signal (e.g. 0-10 V or 4-20 mA); the full pressure control range can be continuously covered. If the user requires more than two different system pressures, an electrical setpoint device (SWG-10 BCD) is available as an accessory; up to seven setpoints can be adjusted.

Series SPB valves are often used with frequency-controlled positive displacement pumps. The valves handle the lightning-fast pressure control requirement and also provide burst protection. In this system, the frequency-controlled pumps deliver the required amount of coolant, so a particularly energy-efficient combination is offered to the user. The electricity costs of the pump are minimized and the heat input into the coolant is significantly reduced. This series is mainly used with the coolant group of media consisting of oils or emulsions.

Options

Many DBV’s are available with SAE port connections according to DIN ISO 6162 instead of socket threads. Stainless steel is often available as the housing material as an alternative to galvanized steel. The proportional valves are also available as IO-Link versions. Various adapter plates, special pressure gauges or additional safety valves complete the range of options.

DBV valves are available with nominal orifice sizes of approx. 0.31" to 2.50" with a pressure control range of 6000 psi maximum. The flow factor (Cv value) ranges from 1.3 to 69 GPM.

Our website’s homepage shows many valve versions that are suitable for a large variety of applications and media. Contact us for selection assistance from numerous variants and also special designs that are not listed on our website. From our product line, we are confident that we can offer a suitable valve for your requirement.

Pressure reducing or inline valves

Often, several valves are connected to a central supply with a fixed pressure level. If all valves work synchronously and always require the same pressure levels, there is no problem. However, if valves have to work with different pressure levels at the same time, pressure reducing valves are required. For this purpose, a pressure reducer is installed in front of each tool. Since the valves are installed in the same line as the tool, not the bypass, the pressure reducing valves are also called inline valves. Many pressure reducers are designed for inlet pressures of 3000 psi. They are able to “dim” the pressure up to 75 psi. Each valve works completely independently with the result that neighboring valves are not affected in any way during operation.

Series (3)-HPI pressure reducing valves are electro-pneumatically actuated. The set pressure can be switched on and off via a power supply, for example 24 Volts DC. When the voltage is switched on, the pressure control is active; when the voltage is switched off, the valve is closed by spring actuation. With Series 3-HPI valves, the pressure is controlled manually; thus, only one pressure level can be selected at a time. We offer two-pressure control as an accessory module. This module can be retrofitted to any valve allowing the user to switch between two system pressures.

The pressure reducing valves of Series SPI operate electro-pneumatically and are controlled via a setpoint signal (e.g. 0-10 V or 4-20 mA); the full range of the pressure control range can be covered continuously. The use of these valve types makes sense if the user requires more than two different system pressures. An electrical setpoint device (SWG-10 BCD) is available as an accessory with which up to seven setpoints can be adjusted.

Pressure reducing valves are available with nominal orifice sizes of approx. 0.31" to 1.25" and with pressure control ranges of 6000 psi maximum. The flow factor (Cv value) ranges from 1.1 to 24 m³/h.

Application

The inline valves are often used in central supply systems when a single pump has to supply several tools with different coolant pressures at the same time. The coolant medium group which consists of oils or emulsions is mainly used. However, the valves are also suitable for other liquids and gases.

Our website’s homepage shows many valve versions that are suitable for a large variety of applications and media. Contact us for selection assistance from numerous variants and also special designs that are not listed on our website. From our product line, we are confident that we can offer a suitable valve for your requirement.

Three-way valves

Three-way valves represent a combination of pressure limiting (bypass) and pressure reducing (inline) valves. They are ideal for precise pressure control in closed systems such as pressure vessels. The system pressure in a closed system can be precisely increased or decreased (vented) up to the full pressure level without causing pressure fluctuations or vibrations.

Three-way valves are available with a nominal orifice size of approx. 0.50" for pressure control ranges from 0 to a maximum of 1500 psi. The flow factor (Cv value) is a maximum of 6.9 GPM.

Application

These valves are often used on gas control test benches, but are also suitable for liquids.

Overview technical data Pressure Control Valves