Discussion on the manufacture method of top mounted handwheel mechanism of pneumatic actuator
1. In electric power, petroleum and chemical industry In metallurgy and other industries, pneumatic actuators usually use remote signal control to meet the requirements of valve opening and closing. However, in case of gas, power and signal failure, the valve must be opened and closed through the handwheel mechanism to ensure the safety of equipment and operators and prevent major safety accidents.
2. At present, the straight stroke double acting piston pneumatic actuator that precisely controls the opening and closing of the valve is realized by configuring an intelligent positioner. In addition, in order to facilitate remote monitoring of whether the valve is fully open or closed, a travel switch is usually used. As precision electrical components, intelligent positioners and travel switches need to be far away from the heat radiation of valves and pipes to ensure their detection accuracy. The existing straight stroke double acting piston pneumatic actuators are usually equipped with top mounted hand wheels. Because of the top mounted hand wheel structure, the feedback position of remote signals can only be set on the lower piston rod connected to the valve rod, so the intelligent positioner and travel switch can only be installed on the lower bracket or cylinder of the actuator, and can not be far away from the thermal radiation.
3. In addition, clutch engagement is widely used in the top mounted handwheel mechanism of the existing straight stroke double action piston pneumatic actuator Separate the split nut, or use the reducer to fit the clutch pin. The top hand wheel of clutch engaging and separating the opening and closing nut needs to divide the whole nut into two halves, which not only reduces the force strength of the nut, affects the service life of the nut, but also increases the difficulty of processing and assembly. The top mounted handwheel adopts a decelerating handwheel, which is cumbersome to operate. It takes time and effort to manually open or close the valve.
