Precautions for valve selection and valve replacement
Necessity of valve model selection
The choice of valve structure model selection is based on the applied medium, temperature, working pressure before and after the valve, total flow, physical properties of the medium, and cleanliness level of the medium. Comprehensive consideration of decision-making. The accuracy and rationalization of valve structure selection are immediately related to application performance, adjustment performance, adjustment reliability, and service life.
The work status information content that must be implemented in the valve model selection
1. Processing process parameters:
1. The name of the medium.
2, the relative density, viscosity, temperature, cleanliness of the medium (with fine particles).
3, the physical and chemical properties of the medium: such as corrosion, side effects, pH.
4. The total flow of the medium: larger, normal, and least.
5. The working pressure before and after the medium valve: larger, everything is normal, and the least.
6. Medium viscosity, the greater the viscosity, the more harmful the calculation of Cv value.
This kind of parameter is mainly used to measure the required specifications of the valve, the rated value Cv value and other specification parameters, and the suitable raw material that the valve should choose.
2. Multifunctional parameters:
1. Posture method: electric, pneumatic, hydraulic, hydraulic press.
2. Valve function: adjust, disconnect, adjust and disconnect simultaneously.
3. Operation method: locator, relay, pressure regulating valve.
4. Posture time regulation.
This part of the parameters is mainly used to clarify some accessories and equipment that must be equipped for the versatility of the valve.
3. Explosion-proof safety protection parameters:
1. The level of protection.
2, waterproof level.
Four. Natural environment and driving force parameters:
1. Natural environment temperature.
2, driving force parameters: pneumatic valve working pressure, switching power supply working pressure.
Common problems with valve disassembly
If the valve is dismantled and replaced, the following specifications and parameters should be given to prevent the inconsistency of the valve manufacturer, or the selected specifications are different, or It is the valve [different structural form, which results in the valve cannot be installed, cannot be installed, or the indoor space is insufficient.