Vacuum Breaker Diaphragm Replacement
Important things to remember:
- Plast-O-Matic recommends keeping a spare diaphragm available for repairs.
- Seal life will vary with applications due to cycles, temperature, pressures, chemicals and concentrations.
- Based on the application, a periodic inspection and maintenance plan should be established.
Preparing for diaphragm installation:
- Before disassembling a valve for examination, cleaning or repair, make sure the liquid line is depressurized and drained. (It should be noted that even after a pump is shut down to eliminate fluid line pressure there may still be pressure trapped in the piping system. One example of this would be head pressure located in a vertical run of pipe. If this situation is possible, extreme caution should be exercised to avoid injuring a worker. CAUTION: Avoid breathing dangerous vapors and avoid skin contact with chemicals.)
- Whenever disassembling a valve, it is wise to carefully inspect all the parts to ensure proper operation when it is reassembled.
Installation of diaphragm:
- Carefully remove and inspect the dust cap.
- Unthread the union nut and remove the inlet housing to allow access to the diaphragm.
- Inspect the inner workings of the valve for debris of signs of chemical attack or wear.
- Remove the existing diaphragm and check that the internal stop (spider) is in good shape and properly installed.
- Install the new diaphragm with the legs properly positioned in the grooves and aligned with the spider.
- Reinstall the inlet by tightening the union nut by hand and then with a quarter turn with a strap wrench. Do not over tighten.
- Reinstall the dust cap.
测试:
- Once the valve is reassembled restart the system/pump slowly and check for leaks.
- Cycle the system as to allow for operation of the vacuum breaker to verify correct operation.
Link to the VBM Installation and Maintenance Instructions sheet.