Control Valve
Control valve, also known as regulating valve, is a final control element in the field of industrial automation process control that changes process parameters such as medium flow, pressure, temperature, and liquid level by receiving the control signal output by the regulating control unit and using power operation. It is generally composed of an actuator and valves.
Basic functions of control valve
Flow regulation: In industrial production, it is often necessary to adjust the flow of the medium according to actual needs. The control valve controls the flow of the medium by changing the opening of the valve to meet the requirements of the production process.
For example, in chemical production, the control valve control the flow of raw materials to ensure the stability of the reaction process and the consistency of product quality.
Pressure regulation: In many industrial systems, the pressure of the medium needs to be kept stable within a range. The control valve can automatically adjust the opening of the valve according to the pressure changes of the system to maintain the stability of the system pressure.
For example, in the water supply system, the control valve can automatically adjust the pressure of the water supply pipeline according to the user’s water demand to ensure that the user gets a stable water pressure.
Temperature regulation: In some industrial processes, the temperature of the medium needs to be controlled. The control valve can adjust the flow rate of the medium and change the heat transfer rate of the medium to achieve temperature regulation.
For example, in the oil refining process,the control valve can adjust the flow rate of the heating or cooling medium according to the process requirements to achieve temperature control.
Fluid regulation and distribution: In some industrial systems, fluids need to be distributed to different pipelines or equipment. The control valve can adjust the flow rate of different pipelines as needed to achieve fluid regulation and distribution.
For example, in the petrochemical industry, the control valve can adjust and distributed the flow rate of raw materials according to the needs of the reactor to ensure the normal operation of the reactor.
Product Type
V8000 Series Control Valve
Application Scenario: In the fields of heating, temperature control, refrigeration and even the entire industrial fluid automation, GLOBE linear control valve, a common and indispensable fluid control component,adjusting the pressure, flow, temperature and liquid level of steam and other fluids by changing the throttling area between the valve core and the valve seat. Conventional LOBE linear control valves are prone to difficulties in disassembly and replacement of valve seats, easy damage and leakage of packing, poor adjustment accuracy, and poor sealing. Especially in high temperature conditions, they are prone to jamming, high vibration and noise, easy breakage and detachment of valve stems, and large leakage. They cannot meet the working conditions. In severe cases, they will cause emergency shutdowns, causing huge losses to users. In the face of the above hidden dangers, VMV has developed the V8000 series control valves to meet customer needs.
Product features:
·High stability of high pressure difference
·Durable sealing under high temperature conditions
·High adjustment accuracy and low leakage
·Long service life of packing
·Easy and convenient on-site maintenance of valves, fast response speed
·Various combinations of valve trims meet customers’ various working conditions and can achieve long-term maintenance-free online operation
Configure pneumatic diaphragm actuators or electric actuators according to the user’s on-site energy.
Key points for control valve selection
01 Process parameters
When selecting a control valve, the process parameters, including pressure, temperature, flow and medium, should be clarified first. For example, when conveying corrosive media, valves with corrosion-resistant materials should be selected; for high-temperature and high-pressure systems, valves made of high-strength materials (such as stainless steel and chromium-molybdenum alloy steel) should be selected first to avoid valve damage due to mismatch of working conditions.
VMV’s V8000 series GLOBE straight-stroke control valves are suitable for large pressure difference, high temperature and high flow conditions, and can ensure the efficient operation of the system; while the V9000 series bellows control valves are more suitable for conditions with strict requirements for leakage control, especially gas and chemical delivery systems, such as chemical gases and steam.
02 Control requirements
Select the appropriate control valve according to the control accuracy requirements. The response speed, switch adjustment accuracy and operation mode of the control valve should meet the requirements of the control system. For working conditions with high requirements for adjustment accuracy, such as heating systems or precise flow adjustment occasions, the V8000 series provides high-precision adjustment performance, such as heating, steam control, etc.; while the V6000 series three-way control valve is suitable for occasions where flow confluence or diversion is required, such as flow control systems.
03 Valve structure
The valve structure includes ordinary single-seat valves, balanced single-seat valves, low-noise valves, multi-stage pressure reduction valves, pilot valves, etc. Different structures are suitable for different working conditions.
For example, the straight-through single-seat valve has a small leakage and is suitable for occasions requiring small leakage; the balanced single-seat valve is suitable for large pressure difference, small actuator thrust, and small leakage.
The structure of the control valve directly affects its operating efficiency, service life and maintenance cost. The V8000 series adopts the traditional straight-stroke GLOBE structure, which is suitable for working conditions that require fine adjustment, high pressure difference, high-speed flushing, and flash cavitation.
04 Actuator
The actuator is the key to the automatic control of the control valve. Common actuators are pneumatic, hydraulic and electric. Pneumatic actuators have fast response and are suitable for systems that require fast switching; electric actuators are suitable for occasions with high adjustment accuracy requirements.
05 Reliability and maintainability
The V9000 series bellows control valve can ensure long-term maintenance-free operation with its bellows technology, while the V8000 series and V6000 series also provide high-quality seals and durable materials to ensure a long service life and low maintenance frequency.
06 Valve structure
VMV’s V8000 series, V9000 series and V6000 series provide cost-effective solutions under different working conditions, especially in situations where high reliability and long-term stable operation are required, and long-term operating costs are effectively controlled.
The impact of correct selection on system performance and life
The appropriate control valve selection can not only improve process efficiency, but also extend the overall service life of the equipment. Improper selection may cause problems such as excessive wear, leakage, and even system failure of the valve, resulting in increased maintenance costs and unexpected downtime. The correct control valve selection ensures the long-term and stable operation of the entire system.
Conclusion
The selection of control valves is not only related to production efficiency, but also to the long-term cost control and safety of the factory. This article introduces in detail the basic functions, types, and key points of the control valve selection. I hope that when you purchase a control valve next time, this knowledge can help you choose the best suitable products.
