If you are planning to import pneumatic air valves from China, you must have a lot of questions. website:www.pneulead-airfrl.com
How should you choose suitable pneumatic air valves such as air frl treatment components, pneumatic control components, pneumatic actuator, etc.?
How do I find a reliable pneumatic air valves factory in China?
How to ensure pneumatic air valves quality?
In this complete guide, you learn everything you need to know about buying pneumatic air valves from China.
Why import pneumatic air valves from China?
When sourcing your pneumatic air valves suppliers overseas, the first question is: which country should I source my product from? I’m not going to bore you with the reason like “China makes the product at low cost”.
Which country is the top exporter of peristaltic pumps in the world?
I’d go straight to the answer, China is the world’s largest exporter of pneumatic air valves.
Which countries import the most pneumatic air valves from China? pneumatic air valves market highlights
The pneumatic air valves market is expected to project a notable CAGR of 6.5% in 2030. pneumatic air valves market to surpass USD 2.03 billion by 2030 from USD 1.02 billion. Due to growing awareness of maintenance cost savings and operational performance, the global demand for pneumatic air valves is expected to expand significantly in the next few years.
pneumatic air valves market: regions pneumatic air valves market is segmented based on regional analysis into five major regions. North America, Latin America, Europe, APAC, and MENA.
As a device that opens and closes the valve by compressing gas, the pneumatic air valve greatly improves the performance of the valve. It is more and more widely used in industrial applications. The amount of use is large and the consumption is fast.
Therefore, in the process of using pneumatic air valves, we should pay attention to the daily maintenance and maintenance of pneumatic air valves. Have you done all the following daily maintenance and maintenance?
Maintenance work of pneumatic air valve
Before using the pneumatic air valve, wash the debris in the valve body with clean water.
Valve seals should be cleaned regularly to prevent leakage and wear.
When the pneumatic air valve is closed, if there is a lot of residual medium in the valve body, cut off the power supply and air source, and release all the pressure for cleaning.
Fully close and fully open the pneumatic air valve several times to verify whether the valve can work normally, check all details, and ensure that the valve is intact.
Tighten the flange nuts and bolts of the pneumatic air valve to prevent the flange connection problem caused by uneven force.
Daily maintenance of pneumatic air valves
When cleaning the valve, we should pay attention that the general medium can be cleaned with water, but if it is a special medium, the corresponding cleaning method should be selected instead of simple flushing.
In the process of disassembling the valve, we must first do the rust removal work on the rusted parts on the surface before disassembling. Use professional tools to remove the base.
The maintenance and replacement of parts and components are handled differently for different parts. For example, the two sealing surfaces of the valve core and valve seat are relatively small rust spots or wear, which can be repaired by mechanical processing. If it is serious, then It needs to be replaced with a new one; if the valve stem is damaged, it can only be replaced with a new one.
We should pay attention to the alignment in the process of assembling the pneumatic air valve, tighten the bolts on the diagonal, and add lubricating oil to the place where lubricating oil should be added. Remember to use the manufacturer’s method for testing and debugging after assembly to ensure that the closing position of the valve core is the same as that of the valve positioner.
Pneumatic air valve uses compressed air as the power source, cylinder as the actuator, and drives the valve with the help of valve positioners, converters and other accessories to realize switching or proportional adjustment, and accepts the control signal of the industrial automation control system to complete the adjustment of the pipeline medium. flow, pressure, temperature, and other process parameters.
At present, pneumatic air valves are widely used in coking, electric power, metallurgy and other process industries, and are an indispensable and important link in the control system. Therefore, it is very important to ensure the stable and reliable operation of the pneumatic air valve. When the pneumatic regulating valve fails, it can be checked according to the common faults of the regulating valve, and the cause of the fault can be found out in time.
1 Air source failure
The on-site air source is not turned on;
The air source contains water, and the weather is cold and icy;
The supply of purified air is stopped;
The air pressure is too low due to the leakage of the air source main pipe or the blockage of the air line, and the regulating valve cannot be fully opened or fully closed, or even does not operate;
The air filter pressure reducer is used for a long time, and there is too much dirt. The black knob under the pressure reducing valve opens and leaks air, so that the output air pressure is lower than the specified pressure, so that the regulating valve cannot be fully opened and fully closed, or even does not operate;
The on-site air line leaks and the joint is loose, resulting in insufficient air pressure, and the regulating valve cannot be fully opened or closed, or even does not operate;
The failure of the filter pressure reducing valve causes the wind pressure to be unstable and causes the adjustment valve to oscillate.
2 line failure
The terminals of the power cord are loose, fall off, short-circuited, or open-circuited. Too much dust on the circuit board leads to poor contact, signal fluctuation, and vibration of the control valve;
After heavy rain or typhoon, the equipment will be wetted by water and the wiring will be short-circuited, resulting in the regulating valve not being able to be fully opened or fully closed;
If the polarity is reversed, the regulating valve will not operate;
The middle section of the power line is faulty, due to the failure of the insulating tape, the insulation of the wire falls off, causing a short circuit between the wires, and the wire is broken due to on-site vibration, resulting in discontinuous oscillation of the regulating valve action, which cannot be fully opened or fully closed or even not. action;
Due to the wrong wiring of the regulating valve after maintenance, the regulating valve is faulty;
The output signal of the control valve is unstable, causing the operation of the control valve to fluctuate.
3 Locator failure
The fixed nut of the feedback rod is loose and falls off, and the spring on the feedback rod falls off, causing the feedback rod to loosen, fall off, and jam, causing the regulating valve to oscillate;
The position sensor in the locator is faulty. When the vibration reaches a dead point, it will cause the central control room to display overtravel, and it will return to normal after a while, which can be solved by replacing it;
The PID parameter setting of the positioner is not suitable;
4 Control valve body failure
The valve core or valve seat of the regulating valve is worn (scouring of the medium, scratches and wear of dirt such as rust, welding slag, etc.), jamming (blocking of various impurities in the medium), and poor sealing (wearing of the sealing ring), resulting in the valve When it is fully closed, the medium is still too much and cannot be controlled;
The control valve disc is pressed too tightly or too loosely. If it is too tight, the valve stem of the control valve will move slowly or jump. If it is too loose, the medium will leak. If the heavy oil is likely to burn, it will cause a big accident;
When the regulating valve is installed, the pipeline and the valve body are not concentric, so that the regulating valve is subjected to excessive additional stress, resulting in vibration, which cannot be fully opened or fully closed;
The valve stem of the regulating valve and the fixing nut of the connecting piece are loose, and the valve stem and the valve core are not concentric, so that the valve does not close, and the stress increases, causing the valve stem to vibrate at high frequency, or even break;
Due to the failure of the diaphragm head of the regulating valve, due to the long-term use of the diaphragm, the aging and deterioration, the reduction of elasticity, the poor sealing performance, the air leakage of the diaphragm, the aging of the compression spring, the reduction of elasticity, and the fracture, resulting in the regulating valve not being able to be fully opened or closed or even The valve core of the out-of-control regulating valve falls off, the valve core and the valve seat are stuck, and the valve stem is bent or broken, which will cause the regulating valve to operate normally, but it will not play a role in regulating.
Pneumatic air valves are valves driven by compressed air. When purchasing pneumatic valves, it is only necessary to specify the specifications, types, and working pressures to meet the purchasing requirements. flow. It is not perfect in the current market economy environment. Because the pneumatic valve manufacturers have carried out different innovations under the concept of unified design of pneumatic valves for product competition, they have formed their own corporate standards and product personality. Therefore, it is very necessary to put forward technical requirements in detail when purchasing pneumatic valves, and coordinate with manufacturers to reach a consensus as an accessory of the pneumatic valve purchase contract.
The compressed air is used to push the movement of multiple sets of combined pneumatic pistons in the actuator, and the force is transmitted to the characteristics of the beam and the inner curved track, which drives the hollow spindle to rotate. Direction, according to the requirements of the rotation torque required by the load (valve), the number of cylinder combinations can be adjusted to drive the load (valve) to work.
1. The purpose of use and maintenance is to prolong the life of the valve and ensure reliable opening and closing.
2. The valve stem thread is often rubbed with the valve stem nut, and a little yellow dry oil, molybdenum disulfide or graphite powder should be applied to lubricate.
3. For valves that are not frequently opened and closed, turn the handwheel regularly, and add lubricant to the valve stem thread to prevent it from being bitten.
4. For outdoor valves, a protective cover should be added to the valve stem to prevent rain, snow, dust and rust.
5. If the valve is mechanically ready to act, add lubricating oil to the gearbox on time.
6. Always keep the valve clean.
7. Always check and maintain the integrity of the other parts of the valve. If the fixing nut of the handwheel falls off, it must be matched and cannot be used properly, otherwise it will grind the square on the upper part of the valve stem, and gradually lose the reliability of cooperation, and even cannot be started.
8. Do not rely on the valve to support other heavy objects, and do not stand on the valve.
9. The valve stem, especially the threaded part, should be wiped frequently, and the lubricant that has been soiled by dust should be replaced with a new one, because the dust contains hard debris, which is easy to wear the thread and the surface of the valve stem, affecting the service life of the pneumatic unit. Seat control valve.