The flange cover plate of fluorine lined valve cannot be opened at will. Unless it is ready to connect with the pipeline, the PTFE flange surface may be damaged or distorted due to temperature difference and foreign matters, which may affect the sealing.
If the cover plate needs to be moved for inspection, the cover plate must be reset quickly after inspection to protect the PTFE flange surface. 2. When the fluorine lined valve is connected with the pipeline, the gasket is generally not used alone, but when it is connected with the flange surface of different materials (metal surface, etc.), appropriate gasket shall be used to protect the flange surface of PTFE. 3. In case of leakage of fluorine lined valve in the use of the system at a higher temperature, the system temperature shall be reduced to room temperature first, and then the cause shall be found out for maintenance. 4. During the installation, the flange nuts shall be tightened evenly in the diagonal direction (symmetrically) and provided with appropriate torque: a if the sealing surface of the flange leaks and the nut at the leaking position has been locked, loosen the nut at the leaking position for half a circle, and then apply the same torque to the opposite side to lock again;
B if the above method does not stop the leakage, check PTFE If there are concave convex indentation and scratch on the flange surface, it can be leveled and reconnected with spinning paper and cloth at that time. 5. It is not allowed to do any high temperature welding work on the fluorine lined valve to avoid permanent damage to the lining layer. 6. Fluorine lined valves shall be stored in a dry and ventilated room, and stacking is strictly prohibited. 7. The fluorine lined valve after maintenance can only be installed after passing the test according to relevant standards before use. 8. When manually operating the fluorine lined valve, it is not allowed to force the valve to open and close by other levers. 9. When installing fluorine lined valves with directional requirements, pay attention to the flow direction of medium along the direction indicated by the arrow on the valve body, and ensure convenient operation and maintenance. 10. The sealing pair of fluorine lined valve stored for a long time shall be in the state of micro opening and separation, so as to avoid permanent deformation of the sealing surface caused by long-term compression, which will affect the sealing performance and service life.