A pneumatic butterfly valve consists of a pneumatic actuator and a butterfly valve. Simply put, it’s created by combining a pneumatic head with a butterfly valve to form a single, integrated unit. However, during assembly, it’s crucial to pay attention to many details. If the assembly is done well, the pneumatic butterfly valve will perform excellently; if the assembly is poor, the quality and usability of the valve will suffer. Based on years of experience, our technicians have compiled the following 12 key details that require careful attention:

　　1. Before assembly, check that all components of the pneumatic butterfly valve are present and correctly matched in model. Also, ensure there is no debris inside the valve body and that the solenoid valve and silencer are free of blockages.

　　2. Place both the valve and the cylinder in the closed position.

　　3. Align the cylinder with the valve—either parallel or perpendicular to the valve body—and then check whether the screw holes are properly aligned. There shouldn't be much deviation. If there is a slight misalignment, simply rotate the cylinder slightly and then tighten the screws.

　　4. After installation is complete, perform commissioning of the pneumatic butterfly valve (under normal circumstances, the supply air pressure should be between 0.4 and 0.6 MPa). During commissioning and operation, the solenoid valve must be manually operated to open and close it (only by manually operating the solenoid valve after de-energizing its coil can the operation be effective). Observe the opening and closing performance of the pneumatic butterfly valve. If, during commissioning and operation, you notice that the valve initially feels somewhat stiff when opening or closing but then operates normally thereafter, you need to reduce the cylinder stroke slightly (simultaneously turn both end-stroke adjustment screws inward a little bit; when making adjustments, ensure the valve is fully open, then turn off the air supply before proceeding with the adjustment) until the valve’s opening and closing actions become smooth and there is no leakage when the valve is fully closed. It is also important to note that the adjustable silencer can regulate the valve’s opening and closing speed, but do not adjust it too small—otherwise, the valve may fail to operate altogether.

　　5. The product must be kept dry before installation and should not be stored outdoors.

　　6. Before installing the butterfly valve, inspect the pipeline to ensure that there are no foreign objects such as welding slag inside.

　　7. The manual opening and closing torque of the butterfly valve body is moderate, and the torque of the butterfly valve matches the torque of the selected actuator.

　　8. The flange specifications for butterfly valve connections must be correct, and the pipe flanges used for clamp-on connections must conform to the standards for butterfly valve flanges. It is recommended to use flanges specifically designed for butterfly valves; flat-welded flanges must not be used.

　　9. Confirm that the flange welding is correct. After the butterfly valve is installed, no further welding of the flange is allowed to avoid scalding the rubber components.

　　10. The installed pipe flanges must be aligned and centered with the butterfly valve that has been inserted.

　　11. Install all flange bolts and tighten them by hand. Confirm that the butterfly valve is properly aligned with the flange, then carefully open and close the butterfly valve to ensure smooth operation.

　　12. Fully open the valve, and use a wrench to tighten the bolts in a diagonal sequence—no washers are required. Be careful not to overtighten the bolts, as this could cause severe deformation of the valve seat and result in excessive opening and closing torque.