Pneumatic control valve of gas source faults elimination method

- - - - - - - - - - - - : pneumatic regulator is compressed air as power source, cylinder as actuator, and by means of electric valve positioner, converters, solenoid valve, a valve to drive the valve such as attachment, realize the switch quantity or proportion type adjustment, industrial automation control system receives the control signal to complete regulating the flow of pipeline medium, pressure, temperature and other process parameters. Pneumatic control valve is to control the characteristics of simple, quick response, and intrinsically safe, do not need another explosion protection measures. Shanghai instrument technicians summarized the three common fault for everyone. One, the effects of moisture and fault after water is compressor suction wet air, formed during cooling. Water rust, influence of pneumatic device element, pneumatic components. The effects of moisture content is as follows. The pipe. Cause pipeline internal rust; Pipeline corrosion, cause air leakage, container burst; At the bottom of the pipe stop moisture air flow is insufficient, the pressure loss increases. 。 Components. Pipe rust, accelerate the filter mesh plug, filter does not work; Pipe rust particles into the internal valve, cause bad action, air leakage; Rust particles that components occlusion, cannot smoothly; Directly influence the gas dynamic components parts, cause poor conversion, air leakage and unstable; Water invasion of actuators, cause bad action; Water droplets into the components inside, can't work; Water flushing oil, make the embellish smooth adverse, valve failure, actuators operate unstable; Stranded water flow caused by deficiency in the valve, the pressure loss increases; Water hammer phenomenon caused damage of components. 。 The environment. To release from vent discharge water, pollute the environment. Water caused by the fault can be adopted to deal with is in addition to water, the compressor outlet temperature drop to make the water droplets, water analysis and ruled out. To this end, after pressure indentation machine should be set up and install the cooler and separator, install the air filter in the compressor population. Horizontal line has a slope, in the low end of the drain valve is installed. Export to install dryer. In addition to water measures can be adopted are as follows. Adsorptive water by adsorption capability of moisture adsorption materials, such as the use of silica gel, molecular sieve and aluminum plastic b, pressure dehumidification method to improve the pressure, volume was reduced, the temperature is reduced, thus precipitation water droplets. Machinery in addition to water blocking, cyclone separation, etc. In addition to water. Frozen in addition to water use refrigeration equipment make the air cooled below the dew point, the water vapor condenses into water precipitation. Second, the impact of oil content and fault compressor lubricant oil mist with compressed air, heat and sustained be sent out with compressed air, compressed air is the cause of the oil. The influence of oil content is as follows. Deformation of seal ring. Sealing ring contraction, air leak valve failure, components of the output force is insufficient; Seal oil pump, increase the friction, valve cannot move or components of the output force is insufficient; Seal hardening, friction surface wear, increase the air leakage; Friction increases, valves and actuators bad action. 。 The environment. Industrial raw material chemicals place makes raw materials chemical properties have direct contact with the air change; Industrial furnaces and other places of direct contact with the flame fire danger; Use the air measurement instrument for nozzle jam for failure; Requires extreme avoid oil environment, due to valve and actuator oil leakage of sealing parts caused by environmental pollution, oil removal method is used in addition to the oil filter. Using centrifugal filter, for example, in addition to the oil mist particles, using activated carbon adsorption or hole filter oil removal. Three, the effects of dust and fault compressor suction has a dust in the air and into the pneumatic device, pneumatic components caused by friction and damage, and increases the friction. The effects of dust is as follows. Control element. Control element friction and wear and jammed, action failure and cannot reverse; Affect the stability of the voltage regulator. 。 Actuators. Components of friction and wear and jammed, action failure; Reduce the output force. 。 The amplifier has the throttling parts of pneumatic components, etc. Make the nozzle baffle throttle blockage, failure due to oil pollution, dust elimination method is installed air filter in the compressor suction mouth, before entering the pneumatic device with air filter, to clean or replace the filter regularly.