Diaphragm Valves 3" to 6" - HAYWARD Industries, Inc. - #2

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DVIS REV A ECR 406S 01/04/2001 06U9.DOC REPAIR: Maintenance on the diaphragm valves is generally limited to the replacement of the diaphragms. The diaphragm life is affected by application and frequency of cycle. EXTREME CAUTION MUST BE TAKEN WHEN WORKING ON THIS VALVE. THE PIPING SYSTEM MUST BE DEPRESSURIZED AND DRAINED. PROPER CARE MUST BE TAKEN. CONSULT M.S.D.S. (MATERIAL SAFETY DATA SHEETS) INFORMATION REGARDING YOUR SPECIFIC APPLICATION. There is no need to remove the valve from the line to replace the diaphragm. Bolts hold the bonnet to the valve body, sandwiching the diaphragm. The diaphragm material should be selected for compatibility with the specific application. Open the valve. This may require application of air pressure to the actuator on fail-close design actuators. Remove the bonnet bolts and where applicable the washers under the bolts. Remove the bonnet with the diaphragm. On the diaphragm valves, the diaphragm has a right hand thread. Unscrew the diaphragm by rotating it counterclockwise from the compressor. Inspect the diaphragm for wear and replace as needed. Make sure the holes in the diaphragm align with the holes in the bonnet. The seal surface on the diaphragm must be over the weir. In most applications the diaphragm life can be greatly increased by the application of a small amount of silicon lubricant on the compressor side of the diaphragm. Install the bonnet bolts and washers 20-25 Ft*Lb torque.