What is the knowledge of AT pneumatic actuators?
Nowadays, many people don't understand AT pneumatic actuators, so many people don't know how to use AT Pneumatic Actuators.
1. Membrane Actuator
Diaphragm actuators are very commonly used, it can be used as a pushing device for general Control Valves, and form pneumatic diaphragm actuators. The signal pressure p of the pneumatic diaphragm actuator acts on the diaphragm to deform it, drives the push rod on the diaphragm to move, and displaces the valve core, thereby changing the opening of the valve. It has simple structure, cheap price, easy maintenance and wide application.
Pneumatic membrane actuators are available in two forms: positive and reactive.
When the signal pressure from the controller or valve positioner increases, the downward action of the valve stem is called the positive action actuator; When the signal pressure increases, the valve stem moves upwards is called a reaction actuator. The signal pressure of the positive-acting actuator is through the membrane air chamber above the corrugated diaphragm; The signal pressure of the reaction actuator is through the membrane air chamber below the corrugated diaphragm. By replacing individual parts, the two can be retrofitted with each other.
2. Piston Actuator
The pneumatic Piston Actuator causes the piston to move in the cylinder to generate thrust, and obviously, the output force of the piston type is much greater than that of the diaphragm type. Therefore, the film type is suitable for occasions with small output and high precision; The piston type is suitable for applications with large output forces, such as large diameters, high pressure drop control or push devices for butterfly valves. In addition to the diaphragm type and piston type, there is also a long-stroke actuator, which has a long stroke and a large torque, which is suitable for the occasion of output angular displacement and high torque.
The standard for the signal received by the Pneumatic Actuator is 0.02 to 0.1MPa.
The main components of the pneumatic piston actuator are cylinders, pistons, and push rods. The piston in the cylinder moves with the change in the pressure difference between the two sides of the cylinder. According to the characteristics, it can be divided into two types: proportional and two-digit. The two-position type pushes the piston from the high-pressure side to the low-pressure side according to the amount of operating pressure on both sides of the input piston. The proportional type is based on the two-position type with a valve positioner, so that the displacement of the push rod and the signal pressure are proportional.
3. Rack and pinion actuator
Rack and pinion type (double piston rack and pinion type) pneumatic actuator has the characteristics of compact structure, beautiful appearance, fast response, stable operation and long service life. All accessories are equipped with advanced anti-corrosion treatment technology, which can adapt to various harsh working conditions. Its actuators with high and low temperatures and various special strokes have good performance in various applications.
