Instruction Manual
D104191X012
Fisher™ CCV-N Control Valves
CCV-N Valve
October 2018
Contents
Introduction 1.................................
Scope of Manual 1.............................
Specifications 2...............................
Description 2.................................
Educational Services 2.........................
Installation 3..................................
Maintenance 4.................................
Packing Maintenance 5.........................
Replace Packing 5.............................
Trim Maintenance 8...........................
Disassembly 8.............................
NPS 4 Balanced Bore-Seal Maintenance 8......
Valve Plug Maintenance 10..................
NPS 4 Balanced Bore-Seal
Valve Plug Maintenance 10...............
Assembly 12..............................
Parts Ordering 15...............................
Parts Kits 15...................................
Parts List 17...................................
Figure 1. Fisher NPS 2 CCV-N
X1430
Introduction
Scope of Manual
This instruction manual includes installation, maintenance and parts information for NPS 2 through 4 CCV-N fuel gas
control valves. These valves are used in gas turbines which meter the fuel gas to the combustion chamber of the
turbine and provide linear flow with the ability to choke very quickly at a low pressure drop. Refer to separate manuals
for instructions covering the actuator and accessories.
Do not install, operate, or maintain CCV-N valves without being fully trained and qualified in valve, actuator,
and accessory installation, operation, and maintenance. To avoid personal injury or property damage, it is
important to carefully read, understand, and follow all the contents of this manual, including all safety
cautions and warnings. If you have any questions about these instructions, contact your Emerson sales office
proceeding.
www.Fisher.com
before
CCV-N Valve
October 2018
Table 1. Specifications
Instruction Manual
D104191X012
Valve Sizes
NPS 2 3 4
End Connection Style
(1)
Shutoff Classification
Class IV shutoff per ANSI/ FCI 70-2
Flow Direction
Flow Down
CL300 and CL600 Raised Face (RF) Flanges per ASME
B16.5
Maximum Inlet Pressure and Temperature
(1)
Consistent with CL300 pressure-temperature ratings
to 316C (600F)
Flow Characteristic
Linear from 10% to 100% travel
Approximate Weights
RATING
Consistent with CL600 pressure-temperature ratings
to 370C (700F)
CL300
Maximum Pressure Drop
Consistent with pressure-temperature ratings per
CL600
ASME B16.34
1. The pressure/temperature limits in this manual and any applicable standard or code limitation for valve should not be exceeded.
VALVE SIZE,
NPS
2 31 68
3 51 112
4 77 168
2 31 68
3 51 112
4 87 190
WEIGHT
Kg lbs
Description
CCV-N valves are single port, angle-style, and balanced or unbalanced valves with metal seat, seat ring retainer guide,
and push-down-to-close valve plug action.
Educational Services
For information on available courses for Fisher CCV-N fuel gas control valves, as well as a variety of other products,
contact:
Emerson Automation Solutions
Educational Services - Registration
Phone: 1-641-754-3771 or 1-800-338-8158
E-mail: education@emerson.com
emerson.com/fishervalvetraining
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Installation
WARNING
Always wear protective gloves, clothing, and eyewear when performing any installation operations to avoid personal
injury.
Personal injury or equipment damage caused by sudden release of pressure may result if the valve assembly is installed
where service conditions could exceed the limits given in table 1 or on the appropriate nameplates. To avoid such injury or
damage, provide a relief valve for over-pressure protection as required by government or accepted industry codes and
good engineering practices.
Check with your process or safety engineer for any additional measures that must be taken to protect against process
media.
If installing into an existing application, also refer to the WARNING at the beginning of the Maintenance section in this
instruction manual.
CAUTION
When ordered, the valve configuration and construction materials were selected to meet particular pressure, temperature,
pressure drop, and controlled fluid conditions. Since some valve body/trim material combinations are limited in their
pressure drop and temperature ranges, do not apply any other conditions to the valve without first contacting your
Emerson sales office
.
1. Before installing the valve, inspect the valve and associated equipment for any damage and any foreign material.
2. Make certain the valve body interior is clean, that pipelines are free of foreign material, and that the valve is
oriented so that pipeline flow is in the same direction as the arrow on the side of the valve.
3. It is recommended the valve should be installed in the vertical orientation with the actuator vertical above the
valve. Other positions may result in uneven valve plug, seal set, seat ring, seat ring retainer, packing wear and
improper operation. For more information, consult your Emerson sales office.
4. It is recommended the valve upstream pipe inside diameter should match or be close to valve body inlet inside
diameter to reduce valve inlet turbulence.
5. It is recommended to have a length of 6 to 12 pipe diameters of straight pipe upstream of the valve body inlet and 4
to 8 pipe diameters length downstream of the valve seat ring outlet. The straight pipe upstream and downstream
of the valve body should have a smooth inside surface with no weld slag or other inside surface irregularities. It is
recommended that pipe reducers not be installed in the straight pipe upstream and downstream of the valve.
6. Use a suitable gasket between valve and pipeline flanges.
7. If continuous operation is required during inspection or maintenance, install a three-valve bypass around the
control valve assembly.
8. Refer to the actuator mounting procedure in the appropriate actuator instruction manual.
WARNING
Personal injury could result from packing leakage. Valve packing was tightened before shipment; however, the packing
might require some readjustment to meet specific service conditions.
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Instruction Manual
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Valves with ENVIRO‐SEAL live‐loaded packing or HIGH‐SEAL live‐loaded packing will not require this initial
re‐adjustment. See the Fisher instruction manuals, ENVIRO‐SEAL Packing System for Sliding‐Stem Valves
(D101642X012
) or HIGH‐SEAL Live‐Loaded Packing System (D101453X012) (as appropriate), for packing instructions.
If you wish to convert your present packing arrangement to ENVIRO‐SEAL packing, refer to the retrofit kits listed in the
Parts Kit sub‐section near the end of this manual.
Maintenance
Valve parts are subject to normal wear and must be inspected and replaced as necessary. Inspection and maintenance
frequency depends on the severity of service conditions. This section includes instructions for packing maintenance
and trim maintenance. All maintenance operations may be performed with the valve in the line.
WARNING
Avoid personal injury or property damage from sudden release of process pressure. Before performing any maintenance
operations:
Do not remove the actuator from the valve while the valve is still pressurized.
Always wear protective gloves, clothing, and eyewear when performing any maintenance operations to avoid personal
injury.
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.
Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure
from both sides of the valve. Drain the process media from both sides of the valve.
Release the actuator loading pressure and relieve any actuator spring pre-compression.
Use lock-out procedures to be sure that the above measures stay in effect while you work on the equipment.
The valve packing box 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, or when
loosening the packing box pipe plug.
Check with your process or safety engineer for any additional measures that must be taken to protect against process
media.
CAUTION
Follow instructions carefully to avoid damaging the product surfaces, which could result in damage to the product. Protect
all surfaces of the valve plug, valve seat ring, and seat ring retainer during maintenance to ensure control valve accuracy
and choking performance is not affected.
Note
Whenever a gasket seal is disturbed by removing or shifting parts, a new gasket should be installed upon reassembly. This is
necessary to ensure a good gasket seal, since the used gasket may not seal properly.
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Packing Maintenance
Note
For valves with ENVIRO‐SEAL packing, see the Fisher instruction manual, ENVIRO‐SEAL Packing System for Sliding‐Stem Valves,
D101642X012
If there is undesirable packing leakage, first try to limit the leakage and establish a stem seal by tightening the packing
flange nuts.
If the packing is relatively new and tight on the stem, and if tightening the packing flange nuts does not stop the
leakage, it is possible that the valve stem is worn or nicked so that a seal cannot be made. The surface finish of a new
valve stem is critical for a good packing seal. If the leakage comes from the outside diameter of the packing, it is
possible that the leakage is caused by nicks or scratches around the packing box wall. If performing any of the
following procedures, inspect the valve stem and packing box wall for nicks and scratches.
, for packing instructions.
Replace Packing
WARNING
Refer to the WARNING at the beginning of the Maintenance section in this instruction manual
1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the
process media from both sides of the valve. If using a power actuator, also shut off all pressure lines to the power
actuator, and releases all pressure from the actuator. Use lock-out procedures to be sure that the above measures
stay in effect while you work on the equipment. Observe the Warnings at the start of the Maintenance section.
2. Disconnect the operating lines from the actuator and any leak-off piping from the bonnet. Disconnect the stem
connector and remove the actuator from the valve.
3. Loosen the packing flange nuts (key 5, figures 3, 4, and key 212, figure 5) so that the packing is not tight on the
valve stem (key 7, figures 6, 7, 8, 12, 13, and 14). Remove any travel indicator parts and stem locknuts from the
valve stem threads.
WARNING
To avoid personal injury or property damage caused by uncontrolled movement of the bonnet, loosen the bonnet by
following the instructions in the next step. Do not remove a stuck bonnet by pulling on it with equipment that can stretch
or store energy in any other manner. The sudden release of stored energy can cause uncontrolled movement of the bonnet.
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Figure 2. Packing Arrangements
DOUBLE PTFE
DOUBLE PTFE
UPPER WIPER
(KEY 12)
PACKING
FOLLOWER (KEY 13)
FEMALE
ADAPTER
PACKING RING
MALE
ADAPTER
LANTERN RING
(KEY 8)
PACKING BOX
RING (KEY 11)
12.7 mm
12.7 mm
(1/2 INCH) STEM
(1/2 INCH) STEM
NOTE:
PACKING SET (KEY 6) CONTAINS A FEMALE ADAPTER,
1
V-RING PACKING RINGS, MALE ADAPTER, AND LOWER WIPER RINGS.
LOWER WIPER
1
1
1
1
NOTE: INSTALL SACRIFICAL WASHERS AT PLACES MARKED 'W'
1
HAS THE APPEARANCE OF DIE FORMED GRAFOIL MATERIAL.
HAS THE APPEARANCE OF A WOVEN OR BRAIDED RING.
2
GRAPHITE LEAK-OFF
W
W
12.7 mm
(1/2 INCH) STEM
PACKING
FOLLOWER (KEY 13)
GRAPHITE RIBBON
PACKING RING (KEY 7)
LANTERN RING
(KEY 8)
GRAPHITE FILAMENT
PACKING RING (KEY 7)
PACKING BOX
RING (KEY 11)
4. Hex nuts (key 16, figures 6, 7, 8, 12, 13, and 14) attach the bonnet (key 1, figures 3, 4, and 5) to the body (key 1,
figures 6, 7, 8, 12, 13, and 14). Loosen these nuts approximately 3 mm (1/8 inch). Then loosen the body-to-bonnet
gasketed joint by either rocking the bonnet or prying between the bonnet and valve. Work the prying tool around
the bonnet until the bonnet loosens. If no fluid leaks from the joint, remove the nuts or cap screws completely and
carefully lift the bonnet off the valve.
1
2
CAUTION
Avoid damaging the seating surface caused by the valve plug and stem assembly dropping from the bonnet (key 1, figure 3)
after being lifted partway out. When lifting the bonnet, temporarily install a valve stem locknut on the valve stem. The
locknut will prevent the valve plug and stem assembly from dropping out of the bonnet.
5. Remove the locknut and separate the valve plug and stem from the bonnet. Set the parts on a protective surface to
prevent damage to gasket or seating surfaces.
6. Remove the bonnet gasket (key 10 and 12, figures 6, 7, 8, 12, 13, and 14) and cover the opening in the valve to
protect the gasket surface and prevent foreign material from getting into the valve body cavity.
CAUTION
To prevent possible product damage, cover the opening in the valve in the following procedure to prevent foreign material
from getting into the valve body cavity.
7. Remove the packing flange nuts, packing flange, upper wiper, and packing follower when applicable (keys 3, 5, and
13, figure 4). For Enviro-Seal Graphite ULF packing, remove the packing flange nuts, packing flange, and spring pack
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assembly (keys 201, 212, and 217, figure 5). Carefully push out all the remaining packing parts from the valve side
of the bonnet using a rounded rod or other tool that will not scratch the packing box wall. Clean the packing box
and the metal packing parts.
8. Inspect the valve stem threads and packing box surfaces for any sharp edges which might cut the packing.
Scratches or burrs could cause packing box leakage or damage to the new packing. If the surface condition cannot
be improved by light sanding, replace the damaged parts by following the appropriate steps in the Trim
Maintenance procedure.
9. Remove the covering protecting the valve body cavity and install new bonnet gaskets (key 10 and 12, figures 6, 7,
8, 12, 13, and 14) making sure the gasket seating surfaces are clean and smooth. Then slide the bonnet over the
stem and onto the stud bolts (key 15, figures 6, 7, 8, 12, 13, and 14.)
WARNING
Personal injury or damage to equipment could occur if improper stud and nut materials or parts are used. Do not operate or
assemble this product with stud(s) and nut(s) that are not approved by Emerson/Fisher engineering and/or listed on the
serial card provided with this product. Use of unapproved materials and parts could lead to stresses exceeding the design
or code limits intended for this particular service. Install studs with the material grade and manufacturer's identification
mark visible. Contact your Emerson sales office
approved parts is suspected.
10. Lubricate the bonnet studs (key 15, figure 6, 7, or 8) and all surfaces the studs and nuts come into contact with.
Make sure the nuts material matches the valve specification and set the nut surface with material specification
stamp facing up, therefore it is visible. Tighten the nuts (key 16, figures 6, 7, 8, 12, 13, and 14) in a uniform,
multistage cross pattern. Monitor the distance between the bonnet and body and keep it even to ensure that the
bonnet is being torqued evenly. Use no more than 1/4 of the specified torque as indicated in table 2
crisscross pattern, work up to the specified torque in 1/4 increments until the final torque is achieved. Wait a
minimum of 2 minutes to allow for gasket/screw relaxation and recheck the torque, retightening as necessary. After
final torquing, ensure there is an even gap and that the metal-to-metal contact between the valve body (or bonnet
spacer) and bonnet is achieved around the entire circumference of the body-bonnet joint.
representative immediately if a discrepancy between actual parts and
. Repeat the
Table 2. Body-to-Bonnet Torque Guidelines
VALVE SIZE,
NPS
2 91 67 60 44
3 122 90 85 63
4 163 120 118 87
Nm Lbf‐in Nm Lbf‐in
SA193-B7 Studs S20910 (Nitronic 50) Studs
BOLT TORQUES
11. Install new packing and the metal packing box parts according to the appropriate arrangement in figure 2. For
Enviro-Seal Graphite ULF packing only, see figure 5, parts list in this instruction manual and ENVIRO-SEAL Packing
System for Sliding-Stem Valves Instruction Manual (D101642X012
) for packing arrangement and installation,
complete step 11, then move to step 14. Place a smooth-edged pipe over the valve stem and gently tap each soft
packing part into the packing box.
For all other packing, except Enviro-Seal packing, move to step 12.
12. Slide the packing follower, upper wiper (not applicable for graphite leak-off packing), and packing flange (keys
3,13, 12, figure 3 or 4) into position. Lubricate the packing flange studs (key 4, figure 3 or 4) and the faces of the
packing flange nuts (key 5, figure 3 or 4). Install the packing flange nuts.
13. For graphite leak-off packing, tighten the packing flange nuts to the maximum recommended torque shown in
table 3. Then, loosen the packing flange nuts, and retighten them to the recommended minimum torque shown in
table 3.
For other packing types, tighten the packing flange of the nuts alternatively in small increments until one of the
nuts reaches the minimum recommended torque shown in table 3. Then, tighten the remaining flange nut until the
packing flange is level and at a 90-degree angle to the valve stem.
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Table 3. Recommended Torque for Packing Flange Nuts
Packing
PTFE Packing 12.7 1/2 CL300 3 30 5 42
Graphite Leak-off
Packing
STEM SIZE
mm inch Nm Lbf‐in Nm Lbf‐in
12.7 1/2
Rating
CL300 7 59 10 88
CL600 9 81 14 122
MINIMUM TORQUE MAXIMUM TORQUE
14. Mount the actuator on the valve assembly and reconnect the actuator and valve stem according to the procedure
in the appropriate actuator instruction manual.
Trim Maintenance
Non-Bore Seal Trim Constructions
WARNING
Refer to the WARNING at the beginning of the Maintenance section in this instruction manual.
CAUTION
Follow instructions carefully to avoid damaging the product surfaces, which could result in damage to the product. Protect
all surfaces of the valve plug, valve seat ring, and seat ring retainer during maintenance to ensure control valve accuracy
and choking performance is not affected.
Disassembly
1. Remove the actuator and the bonnet according to steps 1 through 6 of the Replacing Packing procedure in the
Maintenance section.
WARNING
To avoid personal injury due to leaking fluid, avoid damaging gasket sealing surfaces. The surface finish of the valve stem
(key 7, figure 6, 7, 8, 12, and 13) is critical for making a good packing seal. The inside surface of the seat ring retainer (key 3,
figure 6, 7, 8, 12, and 13), is critical for smooth operation of the valve plug. The seating surfaces of the valve plug (key 2,
figure 6, 7, 8, 12, and 13) and seat ring (key 9, figure 6, 7, 8, 12, and 13) are critical for proper shutoff. Unless inspection
reveals otherwise, assume all these parts are in good condition and protect them accordingly.
2. Remove the packing flange nuts, packing flange, upper wiper (not applicable for graphite leak-off packing), and
packing follower (keys 3, 5, 12, and 13, figure 3 or 4). For Enviro-Seal packing, remove the packing flange nuts,
packing flange, and spring pack assembly (key 201, 212, and 217, figure 5.) Carefully push out all the remaining
packing parts from the valve side of the bonnet using a rounded rod or other tool that will not scratch the packing
box wall. Clean the packing box and the metal packing parts.
3. Inspect the valve stem threads and packing box surfaces for any sharp edges which might cut the packing.
Scratches or burrs could cause packing box leakage or damage to the new packing. If the surface condition cannot
be improved by light sanding, replace the damaged parts.
4. On a CCV-N design with bonnet spacer, remove the bonnet spacer (key 32, figure 6 and 12) and associated gaskets
(key 10 and 12, figure 6 and 12) on top of the spacer without rotating the seat ring retainer (key 3, figure 6 and 12).
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5. Mark the orientation between valve body (key 1, figures 6, 7, 8, 12, and 13) and seat ring retainer (key 3, figure
figures 6, 7, 8, 12, and 13). Remove the seat ring retainer, valve plug and stem assembly, and associated gaskets
(key 10, 12, figures 6, 7, 8, 12, and 13).
6. Separate the plug stem assembly and seat ring retainer (key 3, figures 6, 7, 8, 12, and 13) by sliding the plug stem
assembly through the bottom of seat ring retainer.
7. Remove the seat ring (key 9, figure figures 6, 7, 8, 12, and 13) and seat ring gasket (key 13, figures 6, 7, 8, 12, and
13).
8. For all constructions, inspect parts for wear or damage which would prevent proper operation of the valve. Replace
or repair trim parts according to the following procedure for plug maintenance procedure.
NPS 4 Balanced Bore-Seal Trim Maintenance
WARNING
Refer to the WARNING at the beginning of the Maintenance section in this instruction manual.
1. Remove the actuator and the bonnet according to steps 1 through 6 of the Replacing Packing procedure in the
Maintenance section.
WARNING
To avoid personal injury due to leaking fluid, avoid damaging gasket sealing surfaces. The surface finish of the valve stem
(key 7, figure 14) is critical for making a good packing seal. The inside surface of the seat ring retainer (key 3, figure 14) is
critical for smooth operation of the valve plug. The seating surfaces of the valve plug (key 2, figure 14) and seat ring (key 9,
figure 14) are critical for proper shutoff. Unless inspection reveals otherwise, assume all these parts are in good condition
and protect them accordingly.
2. Remove the packing flange nuts, packing flange, and packing follower (keys 3, 5, and 13, figure 4). For Enviro-Seal
packing, remove the packing flange nuts, packing flange and spring pack assembly (key 201, 212 and 217, figure 5).
Carefully push out all the remaining packing parts from the valve side of the bonnet using a rounded rod or other
tool that will not scratch the packing box wall. Clean the packing box and the metal packing parts.
3. Inspect the valve stem threads and packing box surfaces for any sharp edges which might cut the packing.
Scratches or burrs could cause packing box leakage or damage to the new packing. If the surface condition cannot
be improved by light sanding, replace the damaged parts.
4. On a CCV-N design with bonnet spacer, remove the bonnet spacer (key 32, figure 14) and associated gaskets (key
10 and 12, figure 14) without rotating the seat ring retainer (key 3, figure 14).
5. Mark the orientation between valve body (key 1, figure 14), and seat ring retainer (key 3, figure 14).
6. Gently pull the valve stem (key 7, figure 14) up to lift the whole valve plug and stem assembly, seat ring retainer,
Bore-seal and piston rings set (key 2, 4, 7, 8, 17, 18, figure 14) out of valve body (key 1 in figure 14). The plug stem
assembly contains sensitive guiding and sealing surfaces on its outside diameter and care must be taken in its
handling.
7. Locate the break between sections of the piston rings (key 18, figure 14), which should be out of seat ring retainer
by holding the valve stem and seat ring retainer. Using an appropriate tool such as a flat‐blade screwdriver, carefully
pry out the piston rings from the grooves in the Bore Seal retainer.
8. By holding both valve stem and seat ring retainer, place the whole valve plug and stem assembly, seat ring retainer,
Bore-seal trim set on a soft surface such as clean cloth, which will not damage the trim. The valve plug and stem
assembly, seat ring retainer and Bore-seal will remain as a whole trim set. Do not rotate the valve plug and stem
assembly within seat ring retainer. Do not apply any axial force into valve stem which might damage the Bore-seal.
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9. Remove the seat ring (key 9, figure 14) and seat ring gasket (key 13, figure 14).
10. Inspect parts for wear or damage which would prevent proper operation of the valve. Replace or repair trim parts
according to the following procedure for NPS 4 Bore-seal plug maintenance procedure.
Valve Plug Maintenance (Except NPS 4 Balanced Bore-seal Plug)
Except where indicated, NPS 2 key numbers are referenced in figure 6 or 12, NPS 3 key numbers are referenced in
figure 7 or 13, and NPS 4 key numbers are referenced in figure 8.
Note
Due to the design requirement of this product, the valve and stem are precision-matched and the stem is not replaceable. If
damaged, the valve plug and stem must be replaced as an assembly. Contact your Emerson sales office
for parts replacement.
CAUTION
To avoid the valve plug seal ring (key 24) not sealing properly, be careful not to scratch the surfaces of the ring groove in
the valve plug or any of the surfaces of the replacement ring.
Do not remove the valve stem from the plug/retainer assembly unless you are planning to replace the valve stem. Never
reuse an old valve stem with a new plug or reinstall a valve stem after it has been removed. Replacing a valve stem requires
drilling a new pin hole in the stem. This drilling weakens the stem and damage may result in service.
1. With the valve plug (key 2) removed according to the Disassembly portion of the Trim Maintenance procedure,
proceed as appropriate:
2. NPS 2 design for application up to and including 316_C (600_F) (figure 6): Mark the orientation between valve plug
(key 2) and seal retainer (key 4). Punch out the pin (key 8) that connects the valve plug (key 2), stem (key 7) and seal
retainer (key 4). Remove the seal retainer (key 4) with a spanner wrench or strap wrench while counter-holding the
valve plug (key 2) with a second strap wrench, or other suitable tool, to prevent rotation of the valve plug on the
valve stem (key 7). Slide the upper anti-extrusion ring, seal ring, bi-directional back up ring, seal ring, and
anti-extrusion ring (key 63, 24, and 33) off the plug.
Inspect all parts for defects and cleanliness and replace the damaged parts. The removed seal set soft parts should
not be reused. To install the new seal parts, slide the lower anti-extrusion ring, seal ring, bi-directional back up ring,
seal ring, and upper anti-extrusion ring (key 63, 24, and 33) into the plug, as shown in figure 6. Apply anti-seize
lubricant (key 45) to the thread of the seal retainer and flat mating surfaces between the seal retainer and plug (key
2 and 4). Then, install the seal retainer (key 4) into the plug (key 2) and tighten it with a spanner wrench or strap
wrench until the pin holes and previous mark are aligned. Once the holes are aligned, secure the seal retainer (key
4) to the plug stem assembly with a new pin (key 8). Make sure the pin is inserted completely into the assembly with
0.025” depth from the radial surface.
CAUTION
To avoid damaging the seal ring, slowly and gently stretch it for the following procedure. Avoid jerking sharply on the ring.
NPS 3 design for application up to and including 316_C (600_F) (figure 7): Remove the retainer ring (key 26) off the
groove, and slide the back up ring, upper anti-extrusion ring, seal ring, bidirectional back up ring, seal ring, and
anti-extrusion ring (key 63, 24, 25, and 33) off the plug.
Inspect all parts for defects and cleanliness and replace the damaged parts. The removed seal set soft parts should
not be reused. To install the new seal parts, slide the lower anti-extrusion ring, seal ring, bi-directional back up ring,
10
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