Sanitary-grade diaphragm valves may encounter some common problems during installation, which may affect the performance and service life of the valve. The following is the summary of these problems and the corresponding solutions: 

 I. Frequently asked questions before installation 

 1. The model and specifications do not match 

 Problem: The operating conditions of the pipeline were not carefully checked with the scope of application of the diaphragm valve, resulting in a mismatch between the selected model specifications. 

 Solution: Before installation, the operating conditions of the pipeline and the scope of application of the diaphragm valve should be carefully checked to ensure that the selected model specifications are consistent with the design requirements. 

 2. The appearance inspection is not careful. 

 Problem: The appearance of the diaphragm valve was not fully inspected, resulting in damage or deformation of the valve after installation. 

 Solution: Before installation, the appearance of the diaphragm valve should be comprehensively inspected to ensure that there is no damage or rust, and whether the diaphragm is intact and whether there are cracks, holes or signs of aging. 

 II. Frequently asked questions during the installation process 

 1. Improper tightening at the connection 

 Problem: When using bolts to tighten the valve body and the pipe flange, the tightening force is insufficient or excessive, resulting in leakage at the connection. 

 Solution: When using bolts to tighten the valve body and the pipe flange, you should ensure that the connection is firm, but avoid damage caused by excessive tightening. After installation, you should check whether the connection is tight. If it is loose, it should be re-tightened. 

 2. Damage to the diaphragm 

 Problem: During the installation process, the diaphragm was damaged due to improper operation or improper use of tools. 

 Solution: During the installation process, you should operate carefully to avoid using sharp tools or using excessive force to damage the diaphragm. If the diaphragm is found to be damaged, it should be replaced in time. 

 3. Wrong installation direction 

 Problem: The correct installation direction is not determined according to the installation requirements of the diaphragm valve, resulting in inflexible opening and closing of the valve or leaking. 

 Solution: Before installation, you should carefully read the installation instructions of the diaphragm valve to ensure that the correct installation direction is determined according to the requirements. After installation, the opening and closing status of the diaphragm valve should be checked to ensure that it is flexible and not stuck. 

 III. Common problems and solutions after installation 

 1. Leakage problem 

 Reasons: the connection is not tight, the diaphragm is damaged, the sealing surface is deformed, etc. 

 Solution: Check whether the connection is tight, and if it is loose, it should be re-tightened; check whether the diaphragm is damaged, and if so, it should be replaced; check whether the sealing surface is deformed or damaged, and if there is any, it should be repaired or replaced. 

 2. Inflexible opening and closing 

 Reason: The operating mechanism is stuck, the diaphragm is too tight, etc. 

 Solution: Check whether the operating mechanism is flexible, and if there is a jam, it should be cleaned up; check whether the diaphragm is too tight, and if there is any, the flexibility should be adjusted. 

 IV. Other notes 

 1. Avoid brushing grease: Do not paint grease items on the rubber lining layer and rubber diaphragm surface of the sanitary diaphragm valve to prevent rubber from swelling and affect the service life of the diaphragm valve. 

 2. Protect the handwheel or transmission mechanism: the handwheel or transmission mechanism is not allowed to be used for lifting, and collision is strictly prohibited. 

 3. Correct operation: When manually operating the sanitary diaphragm valve, do not use the auxiliary lever to prevent excessive torque and damage to the driving parts or sealing parts. 

 4. Storage requirements: The sanitary diaphragm valve should be stored in a dry and ventilated room, and it is strictly forbidden to stack it. The channels at both ends of the inventory diaphragm valve must be sealed, and the opening and closing parts should be in a micro-opening state. 

 In summary, sanitary diaphragm valves need to pay attention to many aspects during the installation process, including pre-installation preparation, operation during installation, and post-installation inspection and testing. Only by ensuring that each step is correct can the normal operation and service life of the diaphragm valve be guaranteed.