Pressure Control Valves HPB-N 15
Within the family of pressure-regulating valves, a technical distinction is made between series of bypass valves, inline valves and three-way valves.
When machining metals, coolants that consist of oils or emulsions are usually used. The precisely regulated coolant pressure on the tool ensures that the lubricating coolant achieves the best results on the valuable workpiece even at the highest cutting speeds. This is due to the reproducible tolerance and dimensional accuracy as well as the highest surface quality of the workpieces in series production.
On the other hand, the metal chips – even from the deepest blind holes – can only be rinsed out safely with the precisely regulated coolant pressure. This ensures perfect cooling of the tool cutting edges and prevents premature tool wear.
Our SPB and (3) HPB series pressure control valves ensure precise pressure control regardless of the amount of coolant. The coolant requirement on the tool can fluctuate enormously, depending on the machining cycle in which the tool is located: e.g. during the tool change cycle, switch tool on and off, feeds, etc. The excess coolant is returned to the coolant tank via the valve without pressure fluctuations being recognizable. On the one hand, the pressure regulating valves supply the system with a precise coolant pressure, on the other hand they protect the pipes and pumps against damage caused by overpressure due to their operating principle. That is why the 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 the 3-HPB valves is done manually; thus only one pressure level can be selected at a time. The valves are operated electropneumatically: the set pressure is switched on and off via a power supply, e.g. with 24 V.
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 off, all of the coolant flows into the tank; this is called a pressure-minimized circulation circuit. This circulation switch is always suitable for soft start of the positive displacement pumps or for changing tools and workpieces if no coolant is required.
We offer a two-pressure control as an accessory. This module can be retrofitted to any valve. This enables the user to switch between two system pressures.
The bypass valves of the SPB series operate electropneumatically and are controlled by a setpoint signal (e.g. 0-10 V or 4-20 mA). The full range of the pressure control range can be continuously covered. 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 if required. The SPB valve type is often used together with frequency-controlled positive displacement pumps. The valves take over the lightning-fast pressure control and at the same time provide burst protection. In this system, the frequency-controlled pumps deliver the required amount of coolant as required: a particularly energy-efficient combination for 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 medium group consisting of oils or emulsions.
