Valve pneumatic actuator operation characteristics

The pneumatic butterfly valve is composed of a pneumatic actuator and a butterfly valve. Pneumatic butterfly valve is a circular butterfly plate that rotates with the valve stem to open and close, so as to realize the opening action of the pneumatic valve is mainly used as a cut-off valve, and can also be designed to have the function of adjustment or section valve and adjustment, at present, the butterfly valve is used more and more in low-pressure large and medium-diameter pipelines. Pneumatic butterfly valve classification:

Stainless steel pneumatic butterfly valve, hard seal pneumatic butterfly valve, soft seal pneumatic butterfly valve, carbon steel pneumatic butterfly valve.

Actuator. It adopts a new series of GT pneumatic actuators, with double-acting and single-acting (spring return), gear transmission, safe and reliable;

The large-diameter valve adopts a series of AW type pneumatic actuator pull-fork transmission, with reasonable structure and large output torque, and has double-acting and single-acting pneumatic butterfly valves.

1. Pneumatic butterfly valve gear type double piston, large output torque and small size.

2. The cylinder is made of aluminum and gold, which is light in weight and beautiful in appearance.

3. Manual operation mechanism can be installed at the top and bottom.

4. The rack and pinion connection can adjust the opening angle and rated flow.

5. The butterfly valve actuator can be equipped with telecommunication feedback indication and various accessories to achieve automatic operation.

6. IS05211 standard connection provides convenience for the installation and replacement of products.

7. The knuckle screws adjusted at both ends can make the standard product have an adjustable range of 4° at 0° and 90°. Ensure synchronization accuracy with the valve.

Powder system. There are other factors that need to be taken into account in the powder system of the pneumatic butterfly valve, such as: the material cannot be directly rushed to the valve plate of the valve when it is put into the trolley from above (this impact force will also make the valve unable to close tightly), and the static pressure of the material should not exceed the design pressure of the pneumatic butterfly valve, etc.

The difference between the control valve and the ordinary manual valve is that it can not be regarded as an isolated component, but must be considered as a part of the entire automatic control system, many problems in the use of the control valve are not the problem of selection and configuration, but because the user's understanding of the control valve is insufficient, so that the control valve can not be debugged and coordinated with the control system. As long as we realize the key to the problem, select the valve correctly, and debug the control valve in the system debugging stage, we can greatly reduce the failure rate and make the automatic control system run stably for a long time.

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. While rankings may vary depending on time and market conditions, the following brands are generally considered to be among the top brands in the valve industry:

The following influential first-line brands of water system valves and industrial valves can be used as a reference, but for reference only: Suzhou Neway Valve, Shanghai Guanlong Valve, Shanghai Qizhong Valve, Sanhua, Chaoda, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

Pneumatic ball valve actuators are divided into two working modes: double-acting and single-acting.

How the double-acting working mode works:

When compressed air enters the middle cavity between the two pistons of the cylinder from the air port (2), the two pistons are separated and move to the direction of the two ends of the cylinder, and the air of the air cavity at the two ends is discharged through the air port (4). At the same time, the two piston racks synchronously drive the output shaft (gear) to rotate in the counterclockwise direction. On the contrary, when the air source pressure enters the air cavity at both ends of the cylinder from the air port (4), the two pistons move to the middle direction of the cylinder, and the air of the middle air cavity is discharged through the air port (2).

At the same time, the two piston racks and pinions are synchronized to drive the output shaft (gear) to rotate in a clockwise direction. (If the piston is installed in the opposite direction, the output shaft becomes reversed, which is a double-acting reverse rotation).

How the single-acting mode of operation works:

When the air source pressure enters the middle cavity between the two pistons of the cylinder from the air port (2), the two pistons are separated and move to the direction of the two ends of the cylinder, the springs at both ends are forced to compress, and the air of the air cavity at both ends is discharged through the air port (4), and the two piston racks are synchronously driven to rotate the output shaft (gear) in the counterclockwise direction. After the air source pressure is reversed by the solenoid valve, the two pistons of the cylinder move to the middle direction under the elastic force of the spring, and the air of the middle air cavity is discharged from the air port (2), and the two piston racks are synchronously driven to rotate the output shaft (gear) in the clockwise direction. (If the piston is installed in the opposite direction, the output shaft becomes counter-rotating when the spring is returned, that is, it is a single-acting reverse rotation).

From the above respective working principles, it can be seen that the valve opening and closing of double-acting pneumatic actuators require the thrust of compressed air to be executed. In other words, the pneumatic actuator will remain in a certain position in the event of a loss of air.

The single-acting actuator is a self-resetting type, and after losing the continuous air pressure, the actuator will drive the valve back to the initial set position under the action of spring tension.

Advantages of single acting: it can be reset in case of power failure, disadvantages: expensive.

Advantages of double action: **Relatively cheaper, disadvantages: can not be reset after a power failure, easy to cause losses!

Double-acting shut-off does not move to keep in place, and single-acting shut-off automatically resets the function.

Hello, I am glad to serve you and give you the following answers: no, the pneumatic valve is a valve driven by gas, which can control the flow and pressure of the fluid, while the actuator is a mechanical device driven by an electric motor, which can control the opening and closing of the valve cluster, and the butterfly valve is a valve that controls the flow rate by the butterfly plate, which can control the flow and pressure of the permeable fluid. Causes of the problem:

1.There may be a malfunction in the pneumatic valve's dispatch control system, which causes the valve to not work properly. 2.

The actuator's motor may be faulty, causing the valve to not function properly. 3.There may be a fault in the butterfly plate of the butterfly valve, causing the valve to not function properly.

Workaround:1Check the control system of the pneumatic valve and replace the parts that may be faulty to ensure the proper operation of the valve.

2.Check the motor of the actuator and replace the parts that may be faulty to ensure that the valve is working properly. 3.

Inspect the butterfly plate of the butterfly valve and replace the parts that may be faulty to ensure the proper operation of the valve. Steps:1

Check the control system of the pneumatic valve, check whether the power supply of the motor is normal, check whether the control circuit of the control system is normal, and check whether the control components of the control system are normal. 2.Check the motor of the actuator, check whether the power supply of the motor is normal, check whether the control circuit of the motor is normal, and check whether the control elements of the motor are normal.

3.Check the butterfly plate of the butterfly valve, check whether the control circuit of the butterfly plate is normal, check whether the control elements of the butterfly plate are normal, and check the butterfly plate.

Double-acting pneumatic actuator is the pneumatic actuator begins to rotate to open the valve when ventilating, when the valve is to be closed, the other side can be closed by ventilation, it is reset by the cylinder, and can only remain in place when the air source is lost;

Single-acting pneumatic actuator opens the valve in the case of ventilation, and automatically closes without ventilation source, single-acting pneumatic actuator automatically resets by spring, generally used more in dangerous working conditions, and conveys combustible gas or combustible liquid in the diagram, when the gas source is lost and there is an emergency, the single-acting pneumatic actuator can automatically reset to minimize the danger, and the double-acting is generally not easy to reset.

Single-acting pneumatic actuators are generally divided into normally open type and normally closed type.

Normally open type: ventilation is turned off, and the air is turned off.

Normally closed type, ventilation open, gas off.

In general working conditions, there are more double-acting cylinders, and there are no springs for double-acting cylinders, so the cost is lower than that of single-acting pneumatic actuators.

Double-acting pneumatic actuators and single-acting pneumatic actuators are actually similar in use, the most fundamental difference lies in the internal structure, the single-acting actuator has more springs, so its biggest advantage is that it can be reset after power-off!

This advantage is that under dangerous conditions, the valve can be closed by the return of the graph spring, reducing the danger factor! Just like Sinopec, which cooperated with the German Wicken pneumatic actuator before, it was because of the use of this single-acting fork pneumatic actuator that the loss was avoided in an unexpected power outage! Of course, because the single-acting pneumatic actuator has to overcome the resistance of the spring when working, it is necessary to choose a larger model when selecting the type, which will be relatively higher!

To sum up, if the working conditions are dangerous, it is more appropriate to choose a single-acting one! The others are actually pretty much the same!

Internally, the single-acting is mainly more than the double-acting spring design, and the double-acting does not agree that the gas can be reset, and the single-acting power off is reliable after this design is reset, which is used in some high-risk industries. According to the design of the Waiken brand, the single-acting has more cylindrical designs on both sides than the double-acting, and it has built-in springs, and the price is higher than that of the double-acting.

The double action is that you give the air and the pneumatic actuator starts to rotate and open the valve, and when you want to close the valve, you need the other side to give it to close! And the single action means that when you give gas, it will be turned on, and if you don't give gas, it will automatically turn off!

In fact, there is an extra spring inside the single-acting pneumatic actuator, which has been marked in the figure, please check it in detail!

The short ** community of electronic engineers, 5 million+ engineers are using the open app, the composition of pneumatic actuators, the selection network of pneumatic actuators2021-01-211387 sharing posters, electronic knowledge, 1983 people have joined + joined the circle to describe the composition of pneumatic actuators, the types and structures of the adjusting mechanism of pneumatic actuators are roughly the same, mainly because the actuators are different. Therefore, when the pneumatic actuator is introduced, it is divided into two parts: actuator and regulating valve. The pneumatic actuator consists of two parts: an actuator and an adjusting hand valve (adjusting mechanism).

According to the magnitude of the control signal, the corresponding thrust is generated to push the action of the control valve. The regulating valve is the regulating part of the pneumatic actuator, under the action of the thrust of the actuator, the regulating valve produces a certain displacement or rotation angle, and directly regulates the flow of the fluid. 1. The pneumatic installation cover is mainly composed of cylinders, pistons, gear shafts, end covers, seals, screws, etc.; The complete set of pneumatic devices should also include opening indication, stroke limit, solenoid valve, positioner, pneumatic components, manual mechanism, signal feedback and other components.

2. The connection size between the pneumatic device and the valve should be in line with ISO5211 (bottom) and GB T1

Pneumatic actuator is also known as pneumatic actuator and pneumatic actuator, pneumatic actuator can also be divided into single acting and double acting two types: the switch action of the actuator is driven by the air source, called double acting, single acting actuator. Pneumatic valve positioner is one of the important accessories and accessories of valve pneumatic control valve.

It plays the role of valve positioning. The pneumatic valve positioner and the valve pneumatic actuator together constitute an automatic control unit and a variety of regulating valves, which are connected and combined into a pneumatic regulating valve after debugging and installation.

The use of DCS system or PLC control system to remotely give 4-20mA or 0-10V signal, commonly known as pneumatic actuator, so as to achieve the adjustment of valve work, the use of compressed air to carry out the opening and closing of the valve mechanism is called pneumatic actuator: double-acting and single-acting, according to the stroke control is divided into, control the opening of the pneumatic actuator: linear stroke and angular stroke.

The positioner is also divided into straight stroke and angular stroke, and the pneumatic actuator is divided into according to the form of action; Pneumatic cylinders, generally known as pneumatic actuators.

The pneumatic actuator is a valve drive device powered by an air source, and the role of the positioner is mainly to provide the position status of the valve for stroke control.

The mechanism of using compressed air to carry out the opening and closing of the valve is called pneumatic actuator, we are generally called pneumatic actuator, commonly known as pneumatic head cylinder, pneumatic actuator is divided into two kinds according to the form of action: double acting and single acting, and is divided into two kinds according to stroke control: straight stroke and angular stroke.

The positioner also has a straight stroke and angular stroke, using the DCS system or PLC control system to remotely give a 4-20mA or 0-10V signal to control the opening of the pneumatic actuator, so as to achieve the adjustment of the valve work.

The electro-hydraulic actuator is generally composed of four parts: the actuator, the control system, the hydraulic station, and the control operation cabinet (control box). It has the characteristics of intelligent and easy operation of electric actuators, and has the advantages of high precision, high reliability, long life and large load capacity of hydraulic actuators.

It adopts a highly integrated modular structure, which is small in size, simple in structure, very convenient in installation, commissioning and maintenance, and does not require a large independent external oil supply or gas source. This type of actuator is widely used in very important high-reliability, fast-acting occasions.