Maintenance - Emerson Fisher V250 Instruction Manual

V250 Valve
shown in figure 2. When tightening the cap screws
and line bolts, use accepted bolting procedures.
Lubricate the studs or bolts and tighten the nuts in a
crisscross sequence to ensure proper alignment of
the valve with the flanges.
9. For hazardous atmosphere or oxygen service
valves, read the following WARNING, and perform
the instruction provided in the WARNING and
provide the bonding strap assembly mentioned in
Step 10 below if the valve is used in a hazardous
application.
WARNING
The Design V250 is not necessarily
grounded to the pipeline when
installed. If the process fluid or the
atmosphere around the valve is
flammable, personal injury or property
damage could result from an explosion
caused by a discharge of static
electricity from the valve components.
If the valve is installed in a hazardous
area, electrically bond the drive shaft
to the valve.
The packing is composed of all
conductive packing rings (graphite
ribbon packing) to electrically bond
the shaft to the valve for hazardous
area service or non-conductive PTFE
packing rings. For oxygen service
applications, perform the following
step.
10. Attach the bonding strap assembly (key 41,
figure 3) to the shaft with the clamp (key 40, figure
3), and connect the other end of the bonding strap
assembly to the valve with the machine screw (key
43, figure 3).
11. Connect pressure lines to the actuator as
indicated in the actuator instruction manual. When a
manual actuator is used with a power actuator,
install a bypass valve on the power actuator (if not
already supplied) for use during manual operation.

Maintenance

Valve parts are subject to normal wear and must be
inspected and replaced as necessary. The
4
Note
frequency of inspection and replacement depends
upon the severity of service conditions. Instructions
are presented in this section for replacing the shaft
seals, the ball seal or flow ring, the drive and
follower shafts, the ball and bushing, and the valve
outlet gasket.
Key number locations are shown in figure 11 for
single seal and flow ring constructions, and in figure
12 for dual seal constructions.
WARNING
Personal injury or property damage
can result due to a sudden release of
pressure or process fluid if the pipe
plug (key 42, figure 12) is removed
while the valve is pressurized. To
avoid such injury or damage, remove
the pipe plug only when the control
valve is isolated from the pressure
system, or provide a hand valve to
control relief of internal valve pressure
to avoid personal injury or property
damage.
A Design V250 valve with a dual seal construction
contains a pipe plug port (key 42, figure 12) on the
underside of the valve. This port can be used to
relieve internal valve pressure for testing seal
integrity when in the pipeline.
If the pipe plug port is to be used for testing seal
integrity when the valve is in the pipeline, the plug
should be replaced with a hand valve to allow
controlled relief of valve pressure during seal leak
rate testing.
WARNING
Avoid personal injury or damage to
property from sudden release of
pressure or uncontrolled process fluid.
Before starting disassembly:
D Always wear protective gloves,
clothing, and eyewear when
performing any maintenance
operations to avoid personal injury.
Instruction Manual
Form 5206
April 2004