Valves are an important component of industrial piping systems and play an important role in the production process.
Ⅰ. The main function of the valve
1.1 Switching and cutting off media: gate valve, butterfly valve, ball valve can be selected;
1.2 Prevent the backflow of the medium: check valve can be selected;
1.3 Adjust the pressure and flow rate of the medium: optional shut-off valve and control valve;
1.4 Separation, mixing or distribution of media: plug valve, gate valve, control valve can be selected;
1.5 Prevent the medium pressure from exceeding the specified value to ensure the safe operation of the pipeline or equipment: safety valve can be selected.
The selection of valves is mainly from the perspective of trouble-free operation and economy.
Ⅱ. Function of the valve
There are several key factors involved, and here is a detailed discussion of them:
2.1 The nature of the conveying fluid
Fluid Type: Whether the fluid is liquid, gas, or vapor directly affects the choice of valve. For example, liquids may require a shut-off valve, while gases may be more suitable for ball valves. Corrosiveness: Corrosive fluids require corrosion-resistant materials such as stainless steel or special alloys. Viscosity: High-viscosity fluids may require larger diameters or specially designed valves to reduce clogging. Particle content: Fluids containing solid particles may require wear-resistant materials or specially designed valves, such as pinch valves.
2.2 The function of the valve
Switch control: For occasions where only the switching function is required, ball valves or gate valves are common choices.
Flow Regulation: When precise flow control is required, globe valves or control valves are more suitable.
Backflow Prevention: Check valves are used to prevent fluid backflow.
Shunt or Merge: A three-way valve or multi-way valve is used for diverting or merging.
2.3 The size of the valve
Pipe Size: The valve size should match the pipe size to ensure smooth fluid passage. Flow requirements: The size of the valve needs to meet the system flow requirements, and too large or too small will affect the efficiency. Installation Space: Installation space constraints can impact valve size selection.
2.4 Resistance loss of valve
Pressure drop: The valve should minimize pressure drop to avoid affecting system efficiency.
Flow channel design: Full bore valves, such as full bore ball valves, reduce drag loss.
Valve Type: Some valves, such as butterfly valves, have less resistance when opened, making them suitable for low pressure drop occasions.
2.5 The working temperature and working pressure of the valve
Temperature range: Valve materials need to adapt to fluid temperature, and temperature-resistant materials need to be selected in high or low temperature environments.
Pressure level: The valve should be able to withstand the maximum working pressure of the system, and the high-pressure system should choose a valve with a high pressure level.
Combined impact of temperature and pressure: High temperature and high pressure environments require special consideration of material strength and sealing properties.
2.6 The material of the valve
Corrosion resistance: Choose suitable materials based on fluid corrosiveness, such as stainless steel, Hastelloy, etc.
Mechanical strength: The valve material needs to have sufficient mechanical strength to withstand the working pressure.
Temperature adaptability: The material needs to adapt to the working temperature, the high temperature environment needs heat-resistant materials, and the low-temperature environment needs cold-resistant materials.
Economy: On the premise of meeting performance requirements, choose materials with better economy.
Post time: Jul-29-2025
