|
Structurally the pneumatic actuators ПЗН consist of the pneumatic cylinder and the air distributor with one control input, the hydrostatic converter and the sensing element. The pneumatic actuators ПЗН are applied in loading racks, by that they work only in the mode of the local control and provide the forced switching of the drive by the fill-up of the reservoir for providing the closing of the valve. v Pneumatic cylinder (pneumocylinder). The pneumatic cylinder of the pneumatic actuators ПЗН by its construction is analogous to the pneumatic cylinders of the pneumatic actuators ПЗ. The pneumatic cylinder is equipped with the manual alternate, whichprovides emergency control of the drive by the absence of the pneumatic power supply of the power system. v Air distributor The air distributor with one control input has an input for connecting the hydrostatic converter and allows changing the position of the actuator’s rod. v Hydrostatic converter The hydrostatic converter converts the pressure increment in the sensing element, which is caused by the change of the level of liquid in the reservoir. v Sensing element The sensing element converts the liquid level in the reservoir into the pressure increment, which provides switching of the air distributor in the hydrostatic converter. The immersion depth of the sensing element of actuators ПЗН into the poured liquid by the operation is (250 ± 50) mm. |
 |