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The Parts of A Pneumatic Valve Actuator

A component by component walk through a pneumatic valve actuator, so you know what you are looking at when you specify accessories or troubleshoot a valve that will not move.

The Main Assemblies

1. The pneumatic device is mainly composed of cylinders, pistons, gear shafts, end covers, seals, screws, etc.; the complete set of pneumatic devices should also include opening instructions, stroke limits, solenoid valves, positioners, pneumatic components, manual mechanisms, and signals Feedback and other components.

2. The connection size of the pneumatic device and the valve should meet the requirements of ISO5211 (bottom), GB/T12222 and GB/T12223.

Diaphragm Spring and Stem

3. The pneumatic device with manual mechanism should be able to use its manual mechanism to open and close the pneumatic ball valve when the air source is interrupted. When facing the hand wheel, the hand wheel or handle should rotate counterclockwise to open the valve, and rotate clockwise to open and close. The valve is closed.

4. When the end of the piston rod is internally or externally threaded, there should be a wrench mouth suitable for standard wrenches.

Accessories That Bolt Onto It

5. The sealing ring of the piston should be easy to replace and repair.

6. For pneumatic devices with buffer mechanism, the stroke length of the buffer mechanism can refer to the regulations in "Table 1".

Model 410A limit switch box, one of the accessories that mounts on a valve actuator
Model 410A limit switch box, one of the accessories that mounts on a valve actuator

See Model 410A Limit Switch

What Fails and What To Check First

7. The pneumatic device with adjustable buffer mechanism should have a mechanism for adjusting the buffer function outside the cylinder.

8. The thread size of the air inlet and outlet of the cylinder should comply with MANUR NORM (accessory standard) sypv, GB/T7306.1, GB/T7306.2 and GB/T7307.

Products

Models This Article Refers To

Pneumatic valve actuator top view showing visual position indicator and mounting interface
Pneumatic Valve Actuators Pneumatic Valve Actuator This pneumatic valve actuator uses air pressure acting on dual pistons to drive open, close, or adjust valves. View Specifications →
Model 410A limit switch mounted on a valve positioner with YTC bracket
Limit Switches and Pilot Valves Model 410A Limit Switch The Model 410A Limit Switch is an accessory for electro pneumatic valve positioners, designed to detect the end positions of... View Specifications →
Model 210 limit switch mounted on a valve positioner housing
Limit Switches and Pilot Valves Model 210 Limit Switch The Model 210 is a limit switch box supplied as an accessory to the electro pneumatic valve positioner range. View Specifications →
Pilot valve for pneumatic control valve actuators front view
Limit Switches and Pilot Valves Pilot Valve The pilot valve is a pneumatic control component designed for control valve automation, operating alongside pneumatic valve... View Specifications →
FAQ

Questions On This Topic

Which accessories normally mount on an actuator?

A positioner, a limit switch box or position transmitter for feedback, a pilot or solenoid valve for on off duty, and an air filter regulator on the supply.

A valve will not move at all. What do I check first?

Air supply pressure and the filter regulator, then whether the positioner is actually receiving the signal, then the stem clamp and linkage. Most no-movement calls end at air quality or air pressure.

Can a limit switch box be added later?

Yes. A 210, 310, 410A, 410B or 510 box can be fitted to an actuator already in service, and we can supply it already assembled with the positioner.

Do you supply spare accessories separately?

Yes. Stock is held on a quantity of spare accessories, which is why small orders can ship in 2 to 3 days.

Tell Us Which Model You Need

Send a photo of the unit you are replacing, or the model number you want quoted. We confirm the match, the price and the lead time before you commit to anything.

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