Flowserve Cast Flex Wedge Gate Valve - Manual (Page 13)

Cast Flex Wedge Gate Valves FCD ADENIM0010-02
13
5.0 VALVE MAINTENANCE
AnchorlDarling Valves are designed to be essentially maintenance free pieces of equipment. When used in the proper
application and operated correctly they will provide reliable operation for many years. The only area that is expected to require
regular attention is the adjustment and (If necessary) replacement of the stem packing. The frequency of this operation will be
dependent on the service conditions, the type of packing used and the care with which it is installed. Some other maintenance
recommendations are included In the following sections for information.
5.1 Inspection
The most important aspect of valve maintenance is periodic inspection. The early detection of a malfunction can, in
many cases, prevent a minor defect from becoming a major problem. It is very important that leakage from any of the
major seals (packing, disc/seat, body-bonnet) be addressed immediately. The smallest weepage can quickly become
a major problem if it is not treated promptly. Some other areas that should be included in a periodic inspection
program are:
1.
Lubrication:
Stem
Yoke Sleeve
Motor Actuator Drive Sleeve
Pneumatic Actuator Sliding Surfaces
2. Cleaning:
Stem
Packing Area
Pressure Seal Area
Body Bonnet Studs
3. Bolting:
Body-Bonnet
Bonnet Yoke
Motor Actuator
4. Packing Adjustment
5.2 Lubrication
1. Stem: Keep stem threads lubricated with a light coating of grease (NLG1 No. 2 or equal).
2. Yoke Sleeve: Lubricate with general purpose grease every six months. Apply with grease gun to grease fitting
(Item 340).
3. Air cylinder operated valves require only a light coating of grease or oil on the stanchions.
4. Motor Actuator: Every six months, lubricate drive sleeve top bearing, using grease gun on pressure fitting in
housing cover. See Motor Actuator Manual for further information.