DP17 Polit PRV.

Structural Features

• Pilot - operated Structure: The DP17 pilot - operated pressure reducing valve mainly consists of two parts: the main valve and the pilot valve. The pilot valve is used to sense and control pressure changes, and it achieves the pressure - reducing function by controlling the opening of the main valve. The advantage of this structure is that it can control pressure more accurately, has a fast response speed, and stable pressure regulation.

• Diaphragm - type Pilot Valve: The pilot valve usually adopts a diaphragm - type structure. The diaphragm, as a pressure - sensing element, has high sensitivity and reliability. When the inlet pressure changes, the diaphragm can quickly sense it and transmit the pressure signal to the main valve, thus achieving fast and accurate pressure regulation.

• Balanced Main Valve: The main valve is designed in a balanced way, which can effectively counteract the force of the inlet pressure on the valve core, making the opening and closing of the valve core smoother, improving the regulation accuracy and stability of the pressure reducing valve. At the same time, the balanced main valve also has a large flow capacity, which can meet the pressure - reducing requirements of large - flow media.

Working Principle

• When the medium enters the pressure reducing valve from the inlet end, a part of the medium enters the control chamber above the diaphragm through the pilot valve. The inlet pressure acts on the diaphragm, generating a downward force.

• When the inlet pressure exceeds the set value, the pressure below the diaphragm is greater than that above it. The diaphragm deforms upward, driving the pilot valve core to open, allowing the medium in the control chamber to be discharged through the pilot valve.

• The decrease in pressure in the control chamber leads to a reduction in the pressure above the main valve core. Under the action of the inlet pressure and the spring force, the main valve core moves upward, reducing the opening of the main valve, thereby lowering the outlet pressure.

• Conversely, when the inlet pressure is lower than the set value, the diaphragm deforms downward under the action of the spring force, the pilot valve core closes, the pressure in the control chamber gradually increases, and the main valve core moves downward under the pressure difference, increasing the opening of the main valve and raising the outlet pressure. In this way, the DP17 pilot - operated pressure reducing valve can automatically adjust the outlet pressure to keep it within the set range.

Performance Characteristics

• High - precision Pressure Regulation: The DP17 pilot - operated pressure reducing valve can accurately control the outlet pressure within ±5% of the set value, or even with higher precision, making it suitable for systems with strict pressure control requirements.

• Large - flow Characteristics: This pressure reducing valve has a large flow capacity and can meet the pressure - reducing requirements of large - flow media. Its nominal diameter can range from DN15 to DN300 depending on different models, and it can be widely applied to pipeline systems with various flow requirements.

• Good Pressure Stability: Due to the adoption of the pilot - operated structure and the balanced main valve, the DP17 pressure reducing valve can maintain good pressure stability during operation, with small fluctuations in the outlet pressure, providing a stable working pressure for the system.

• Good Adaptability: This pressure reducing valve is suitable for a variety of media, such as gases and liquids, and can work stably under different temperature and pressure conditions. Its working temperature range is generally from - 20℃ to 80℃, and the nominal pressure can reach different levels such as 1.6MPa, 2.5MPa, and 4.0MPa.

Material Selection

• Valve Body Material: The valve body of the DP17 pilot - operated pressure reducing valve is usually made of materials such as cast steel and stainless steel. Cast steel has good strength and toughness and is suitable for general industrial media; stainless steel has excellent corrosion resistance and is suitable for corrosive media or occasions with high hygiene requirements.

• Sealing Material: Sealing parts generally use materials such as rubber and polytetrafluoroethylene. Rubber seals have good elasticity and sealing performance and are suitable for media under general temperature and pressure conditions; polytetrafluoroethylene seals have excellent corrosion resistance and high - temperature resistance and can maintain good sealing effects within a wide temperature range.

Application Fields

• Industrial Automation Systems: In various industrial automation production lines, the DP17 pilot - operated pressure reducing valve is often used to control the pressure in pneumatic or hydraulic systems, ensuring that the equipment and components in the system can work under stable pressure conditions, improving production efficiency and product quality.

• Petrochemical Industry: In petrochemical plants, this pressure reducing valve can be used to reduce the pressure of various chemical media, such as oil, natural gas, and chemical raw materials, to meet the pressure requirements of different technological processes and ensure the safe and stable operation of the production process.

• Power Industry: In thermal power plants, the DP17 pilot - operated pressure reducing valve can be used to reduce the pressure of media such as steam and water, such as steam inlet pressure reduction for steam turbines and feed - water pressure reduction for boilers, ensuring the normal operation of the system and the safety of equipment.

• HVAC Systems: In the heating, ventilation, and air - conditioning systems of buildings, this pressure reducing valve can be used to control the pressure in the air - conditioning water system, steam heating system, etc., ensuring the normal operation of the system and comfort.

Installation and Maintenance

• Installation Requirements: The DP17 pilot - operated pressure reducing valve should be installed on a horizontal pipeline, and a filter should be installed in front of the valve to prevent impurities from entering the pressure reducing valve and affecting its normal operation. During installation, it should be noted that the medium flow direction is consistent with the arrow direction on the valve body, and reverse installation is not allowed. At the same time, ensure that the pressure reducing valve is firmly installed to avoid vibration and displacement during operation.

• Maintenance Points: Regular maintenance of the pressure reducing valve is the key to ensuring its stable performance. Maintenance contents include checking the sealing performance, cleaning impurities, checking the elasticity of the spring and diaphragm, etc. If the sealing parts are found to be aged or damaged, they should be replaced in a timely manner; if the spring or diaphragm has insufficient elasticity, adjustments or replacements should be made. In addition, the pressure reducing valve should be calibrated regularly to ensure that its pressure regulation accuracy meets the requirements.