How to Install Your Pneumatic Ball Valve?

In industrial production, pneumatic ball valves, as efficient and reliable control valves, are widely used in various pipeline systems. Correct installation of pneumatic ball valves not only ensures their normal operation but also extends service life and improves production efficiency. This article will provide a detailed introduction to the installation steps, techniques, and precautions of pneumatic ball valves to help you complete the installation work with ease.

A pneumatic ball valve consists of a ball valve and a pneumatic actuator. The pneumatic actuator operates relatively fast, enabling quick opening and closing of the valve. Pneumatic ball valves are usually equipped with accessories such as solenoid valves, air treatment units, limit switches, and control boxes. These accessories allow the pneumatic ball valve to achieve local control and remote centralized control, so operators can easily control the valve's open/close state from the control room.

The video demonstrates a three-piece ball valve: one piece on the left, the middle with the ball core, and one piece on the right. The connection port adopts a threaded design, and different connection methods can be customized according to different pipeline diameters and thread requirements. This stainless steel ball valve is suitable for pipelines carrying water, liquids, gases, oils, and generally corrosive media.

Before installing a pneumatic ball valve, it is crucial to understand the functions and installation points of its main accessories. These accessories not only determine the valve's performance but also directly affect the stability and reliability of the entire system. The following will provide a detailed introduction to the functions and installation points of the handwheel mechanism, solenoid valve, limit switch, and pneumatic actuator.

When the pneumatic valve loses air or power, the handwheel mechanism can achieve manual control to ensure normal production. The handwheel disc is marked with OPEN and SHUT directional labels for easy operator identification. The handwheel has two function modes: manual and automatic. In manual mode, turning counterclockwise opens, and clockwise closes. When the handwheel is turned, the connecting shaft rotates accordingly.

When the pull rod is lifted upward and the switching lever is lowered, the manual mode switches to automatic control. At this time, turning the handwheel does not move the connecting shaft, and the valve can only be opened and closed pneumatically. Conversely, when the pull rod is lifted upward and the switching lever is raised, automatic switches to manual control, and the valve can be opened or closed directly through the handwheel.

When installing the handwheel mechanism, ensure it is aligned with the pneumatic actuator in the same position (both closed or both open). If directions do not match, the valve will not operate properly.

The solenoid valve is used for electrically controlled pneumatic open/close operation and has low power consumption. There are two connection types: plate-mounted and pipe-mounted. The pipe-mounted solenoid valve has two connection holes on the back, which can be directly connected to the air inlets on the pneumatic actuator. The solenoid valve bottom has three holes: the middle is the air inlet, and both ends are exhaust ports. The plate-mounted solenoid valve achieves valve opening and closing by switching the air source inlet. Its top two connection holes must be connected to the actuator's air inlets via air tubes and can be installed in suitable positions according to the site conditions.

When installing a solenoid valve, note: the outlet ports on the solenoid valve's back must correspond to the actuator's air inlet ports. After installation, secure with screws. The sealing rings inside the solenoid valve connection holes must not be lost, otherwise leakage will occur. In addition, the two connection holes have a correct and reverse direction—if reversed, the valve will react oppositely.

The limit switch internal structure includes 2 cams, 2 micro-switches, 1 wiring terminal, and 1 connecting shaft. When the cam and micro-switch are closed, connecting to a PLC forms a circuit and the PLC indicator light turns on. When the cam and micro-switch are open, the circuit is broken and the PLC light turns off, thereby achieving remote position feedback of the valve. The connecting shaft at the lower end of the limit switch must connect with the top shaft of the pneumatic actuator to achieve 90° open and closed positions according to the actuator's status.

When installing, the protrusion under the connecting shaft must engage with the recess at the top of the actuator and be secured with screws. At the same time, ensure the limit switch remains synchronized with the actuator so positions match.

The pneumatic actuator is the power component of the pneumatic ball valve, responsible for driving the piston movement to achieve a 90° rotation, thereby opening or closing the valve. The actuator has two connection ports corresponding to open and close positions. The top connects with the limit switch, so their positions remain synchronized. The bottom connects with the valve or handwheel mechanism to ensure matching positions.

When installing, ensure its direction matches the handwheel mechanism (both closed or both open). If not aligned, the valve cannot operate normally. In addition, the inner octagon at the actuator's bottom must connect with the outer square at the top of the handwheel mechanism. After connection, secure with screws and tighten.

The square stem of the ball valve connects with the actuator or manual mechanism's inner octagon. The inner octagon size is 14, and the square stem size is 11. During installation, an adapter sleeve (11-to-14) must be fitted on the square stem before connecting to the handwheel. After connection, secure with screws and tighten. Similarly, when connecting the ball valve with the actuator or manual mechanism, both must be in the same position (both closed or both open). If directions differ, the valve will not work properly. All installation steps must comply with ISO5211 standards.

When the manual mechanism is switched to automatic (i.e., switching lever lowered), the top indicator of the limit switch shows yellow for open state (ball also open) and red for closed state (ball also closed).

After preparing the pipeline and accessories, the next step is installing the pneumatic ball valve into the pipeline system. This process requires careful operation to ensure correct installation and avoid potential failures and safety hazards.

Before installation, ensure the front and rear pipelines are ready. The pipeline should be coaxial, the two flange sealing surfaces parallel, and able to bear the valve's weight. If not, supports must be installed. Next, blow clean the front and rear pipelines to remove oil, welding slag, and debris. Check the valve's markings to confirm it is intact. Fully open and close the valve several times to confirm proper operation. Remove protective covers from both ends of the valve flanges, check the bore, remove debris, and clean the bore. Even tiny particles between the seat and ball may damage the seal.

Install the pneumatic ball valve into the pipeline. Either end of the ball valve can be used as the upstream side. For handle-operated valves, installation can be in any position. For gearbox- or pneumatically-driven valves, they should be installed upright on horizontal pipelines, with the actuator on top. Install sealing gaskets between flanges as per design requirements. Flange bolts must be tightened symmetrically, gradually, and evenly to ensure sealing. Finally, connect the pneumatic lines.

Before use, pneumatic ball valves must undergo inspection and open/close testing. Only if operation is normal can they be put into service. During installation, ensure the valve and flanges are concentric and provide supports to prevent deformation or seal damage from external forces. Ensure the air supply for the valve and pneumatic components is clean, oil- and water-free, with cleanliness below 0.4 microns. Before connecting air, clean the supply pipes, interfaces, and switches to prevent dirt from entering the actuator.

Connections of actuator, solenoid valve, positioner, filter, and regulator are recommended with copper or nylon tubes. To reduce noise and dust, install silencers or throttle mufflers at exhaust ports. After installation, test the pneumatic valve. Pressurize the actuator to its rated range (0.4–0.7 MPa). Perform open/close tests and observe. The valve should rotate smoothly without sticking. If sticking occurs, increase air pressure slightly and operate repeatedly until movement becomes smooth.

When commissioning on/off pneumatic ball valves, it is recommended to first test using the manual device (manual button on solenoid valve). After confirming normal operation, perform power-on commissioning. Additionally, pneumatic ball valves should be maintained regularly. Add oil (engine oil) to the stem rotation parts every three months for lubrication. Periodically drain water and dirt from the actuator and air filter. Under normal conditions, inspect every six months and overhaul annually to ensure long-term stable operation.

As efficient and reliable control valves, pneumatic ball valves are widely used in various industrial pipeline systems. Proper installation not only ensures normal operation but also extends service life and improves efficiency. This article introduced the functions, installation points, and pipeline installation steps of pneumatic ball valves and their accessories, aiming to help you complete installation smoothly. During installation, always follow relevant standards and requirements to ensure quality. At the same time, conduct regular maintenance to ensure long-term stable operation.