CV500 Valve
Instruction Manual
Form 5302
July 2006
8
Figure 5. Optional Shaft-to-Body Bonding Strap Assembly
VALVE BODY
ACTUATOR
A
A
VIEW A-A
37A6528-A
A3143-2/IL
D
Disconnect any operating lines
providing air pressure, electric power,
or a control signal to the actuator. Be
sure the actuator cannot suddenly
open or close the valve.
D
Use bypass valves or completely
shut off the process to isolate the
valve from process pressure. Relieve
process pressure on both sides of the
valve. Drain the process media from
both sides of the valve.
D
Vent the power actuator loading
pressure and relieve any actuator
spring precompression.
D
Use lock-out procedures to be
sure that the above measures stay in
effect while you work on the
equipment.
D
Always wear protective gloves,
clothing, and eyewear when
performing any maintenance
operations.
D
The valve packing area may
contain process fluids that are
pressurized,
even when the valve has
been removed from the pipeline.
Process fluids may spray out under
pressure when removing the packing
hardware or packing rings.
D
Check with your process or safety
engineer for any additional measures
that must be taken to protect against
process media.
Valve parts are subject to normal wear and must be
inspected and replaced as necessary. The
frequency of inspection and replacement depends
upon the severity of service conditions.
Packing Maintenance
Key numbers refer to figure 11 for 3- through 8-inch
sizes and to figure 12 for 10- and 12-inch sizes
unless otherwise indicated.
Note
For the ENVIRO-SEAL packing system,
refer to the Parts List section for
retrofit kits, parts kits, and individual
parts (see figures 13 and 14). Refer to
separate ENVIRO-SEAL instruction
manual for maintenance instructions.
Standard ENVIRO-SEAL packing
systems can be used in vacuum
service with packing rings in the
standard orientation. It is not
necessary to reverse the
ENVIRO-SEAL PTFE packing rings.
Stopping Leakage
All maintenance procedures in this section may be
performed with the valve body (key 1) in the line.
For packings other than spring-loaded packing,
leakage around the packing follower (key 14) may
be stopped by tightening the packing flange nuts
(key 16). If leakage cannot be stopped in this
manner, replace the packing according to the
Replacing Packing procedure in this manual.
If the packing is relatively new and tight on the drive
shaft (key 3), and if tightening the packing nuts does
not stop leakage, it is possible that the shaft is worn
or nicked so that a seal cannot be made. If the
leakage comes from the outside diameter of the
packing, it is possible that the leakage is caused by
nicks or scratches on the packing box wall. Inspect
the shaft and packing box wall for nicks or scratches
when performing the following procedures.
Replacing Packing
Note
If the valve has ENVIRO-SEAL
live-loaded packing installed, see the
manual entitled ENVIRO-SEAL Packing
System for Rotary Valves.
