Emerson Y690VB Series User manual

February 1999
Y690VB Series
Instruction Manual
Form 5465
D102594X012
www.FISHERregulators.com
Y690VB Series Vacuum Breakers
Introduction
Scope of Manual
This manual describes and provides instructions and
parts lists for the Type Y690VB and the Type Y690VBM
vacuum breakers. Instructions and parts lists for other
equipment used with these breakers are found in
separate manuals.
Product Description
The Y690VB Series vacuum breakers are used for
precise control of small capacity, low-pressure service
applications where an increase in vacuum must be
limited. These direct-operated vacuum breakers come
in 3/4 (DN 20) and 1-inch (DN 25) body sizes and have
a 1/4-inch (6,4 mm) or 1/2-inch (12,7 mm) orifice. The
individual products are described as follows:
Type Y690VB
The Type Y690VB is a vacuum breaker with internal
pressure registration requiring no downstream
control line.
Installation
Personal injury, property damage, equip-
ment damage, or leakage due to escaping
gas or bursting of pressure-containing
parts may result if this equipment is over-
pressured or is installed where service
conditions could exceed the limits given in
table 1, or where conditions exceed any
ratings of the adjacent piping or piping
connections. To avoid such injury or
damage, provide pressure-relieving or
pressure-limiting devices (as required by
the appropriate code, regulation, or stan-
dard) to prevent service conditions from
exceeding those limits. Additionally,
physical damage to this equipment could
cause personal injury or property damage
due to escaping gas. To avoid such injury
or damage, install the equipment in a safe
and well ventilated location.
Equipment operation within ratings does not preclude
the possibility of damage from debris in the lines or
from external sources. This equipment should be
inspected for damage periodically and after any over-
pressure condition.
WARNING
!!
!!
!
Figure 1. Type Y690VB Vacuum Breaker
W7292
Type Y690VBM
The Type Y690VBM is a vacuum breaker with a control
line connection and a throat seal for external pressure
registration.
Specifications
Table 1 gives some general ratings and specifications
for the Y690VB Series vacuum breakers. Individual
breakers come from the factory with the specific data
stamped on the nameplate.

Y690VB Series
2
Body Sizes
3/4 (DN20) or
1-inch (DN 25)
End Connection Styles(1)
See table 3
Maximum Allowable Inlet (Positive) Pressure(2)
150 psig (10,3 bar)
Vacuum Control Pressure Ranges(2)
See table 2
Maximum Outlet (Casing) Pressure(2)
Full Vacuum
Maximum Emergency Outlet Pressure to Avoid
Internal Parts Damage(2)
150 psig (10,3 bar)
Spring Case Connection
1/4-inch NPT Screwed
1. End connections for other than U.S. standards can usually be provided; consult the Fisher Sales Office or Sales Representative.
2. The pressure/temperature limits in this instruction manual and any applicable standard or code limitation should not be exceeded.
Table 1. Specifications
Orifice Size
1/4-inch (6,4 mm) or 1/2-inch (12,7 mm)
Change in Vacuum Control Pressure
to Wide-Open(2)
See table 2
Pressure Registration
Type Y690VB: Internal
Type Y690VBM: External
Material Temperature Capabilities(2)
Nitrile (NBR):
–20° to 180°F (–29° to 82°C)
Fluoroelastomer (FKM):
40° to 300°F (4° to 149°C)
Ethylenepropylene (EPDM):
–20° to 300°F (–29° to 149°C)
Fluoroelastomer (FKM):
-20° to 300°F (-29° to 149°C)
Approximate Weight
19 pounds (8,6 kg)
Figure 2. Type Y690VB Operational Schematic
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
VACUUM
PUMP VACUUM
BEING
LIMITED
POSITIVE PRESSURE OR
ATMOSPHERE OR A LESSER
VACUUM THAN THE ONE
BEING LIMITED
B2672

Y690VB Series
3
Note
If this equipment is shipped mounted on
another unit, install that unit according to
the appropriate instruction manual.
1. Only personnel qualified through training and experi-
ence should install, operate, and maintain this equip-
ment. For Y690VB Series equipment that is shipped
separately, make sure that there is no damage to or
foreign material in it. Also ensure that all tubing and
piping have been blown free.
2. This equipment may be installed in any position as
long as the flow through the body is in the direction
indicated by the arrow attached to the body. If continu-
ous operation is required during inspection or mainte-
nance, install a three-way bypass valve around the
equipment.
This equipment may vent some gas to the
atmosphere. In hazardous or flammable
gas service, vented gas may accumulate
and cause personal injury, death, or prop-
erty damage due to fire or explosion. Vent
equipment in hazardous gas service to a
remote, safe location away from air intakes
or any hazardous area. The vent line or
stack opening must be protected against
condensation or clogging.
Principle of Operation
The Y690VB Series vacuum breakers (figure 2) are used
in applications where an increase in vacuum must be
limited. An increase in vacuum (decrease in absolute
pressure) is transmitted to the lower side of the dia-
phragm, opening the disk assembly. This permits positive
pressure, atmosphere, or an upstream vacuum that has
Table 2. Vacuum Pressure Information
higher absolute pressure than the downstream vacuum, to
enter the system and restore the controlled vacuum to its
original pressure setting. AType Y690VB (figure 3) direct-
operated vacuum breaker is self-contained and requires no
control line. A Type Y690VBM (figure 4) vacuum breaker
requires a control line from the 1/2-inch NPT tapping in the
diaphragm case assembly to the point where the vacuum
needs to be controlled.
Startup and Adjustment
All Y690VB Series equipment can be placed in opera-
tion by slowly introducing inlet vacuum or pressure. This
equipment takes control when vacuum is established.
This equipment is suitable for the pressure range stamped
on the nameplate (key 46), and listed in table 2. To adjust
the pressure setting, remove the closing cap (key 22)
and turn the adjusting nut (key 20) clockwise to in-
crease the pressure setting or counterclockwise to
decrease the setting. Replace the cap after making this
adjustment. If desired, the closing cap may be wired to
the hole provided in the spring case (key 3) to discour-
age tampering.
Shutdown
First close the nearest upstream shutoff valve and then
close the nearest downstream shutoff valve to vent the
equipment properly. Next, open the vent valve between
the equipment and the downstream shutoff valve
nearest to it. All pressure between these shutoff valves
is released through the open vent valve.
Maintenance
Equipment parts are subject to normal wear and must
be inspected and replaced as necessary. The frequency
of inspection and replacement of parts depends on the
severity of service conditions and upon applicable
codes and government regulations.
WARNING
!!
!!
!
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Y690VB Series
4
O-ring. All pressure must be released from the dia-
phragm case before these steps can be performed.
Type Y690VB
Key numbers are referenced in figure 4.
1. Remove the closing cap (key 22) and turn the
adjusting nut (key 20) counterclockwise until all com-
pression is removed from the control spring (key 6). If
the only further maintenance is to change the control
spring (key 6), skip to step 11.
2. Remove the spring case cap screws (key 24) and
hex nuts (key 23, not shown) and lift off the spring case
assembly (key 3).
3. Remove the diaphragm (key 10) and attached parts
by tilting it so that the pusher post (key 8) slips off the
lever assembly (key 16). To separate the diaphragm from
the attached parts, unscrew the diaphragm hex nut
(key 21). If the only further maintenance is to replace
the diaphragm parts, skip to step 8.
4. To replace the lever assembly (key 16), remove the
machine screws (key 17) .
5. To replace the valve stem (key 14) also perform body
area maintenance procedure steps 1 through 4 and pull
the valve stem (key 14) out of the guide insert (key 18).
6. Install the valve stem (key 14) into the guide insert
(key 18) and perform body area maintenance procedure
steps 5 through 7.
7. Install the lever assembly (key 16) into the valve
stem (key 14) and secure the lever assembly (key 16)
with the machine screws (key 17).
8. Reassemble the diaphragm assembly in the
following order:
€ Pusher post (key 8)
€ Diaphragm head gasket (key 45)
€ Diaphragm head (key 7)
€ Diaphragm (key 10)
€ Diaphragm head (key 7)
€ Washer (key 36)
€ Diaphragm nut (key 38)
Secure with 5 to 6 foot-pounds (7 to 8 N•m) of torque.
9. Install the pusher post (key 8) plus attached dia-
phragm parts onto the lever assembly (key 16).
10. Install the spring case assembly (key 3) and
control spring (key 6) on the diaphragm casing (key 4)
so that the vent assembly is correctly oriented, and
secure them with the spring case cap screws (key 24)
and hex nuts (key 23, not shown) to fingertightness
only.
11. Install the upper spring seat (key 19) and the
adjusting nut (key 20) turning clockwise until there is
To avoid personal injury, property damage,
or equipment damage caused by sudden
release of pressure or explosion of accu-
mulated gas, do not attempt any mainte-
nance or disassembly without first isolating
the regulator from system pressure and
relieving all internal pressure from the
equipment.
Body Area
These procedures are for gaining access to the disk
assembly, orifice, and body O-ring. All pressure must
be released from the diaphragm case before the
following steps can be performed.
Key numbers are referenced in figures 3 and 4.
1. To inspect and replace the disk assembly (key 13)
or orifice (key 5), remove the cap screws (key 2), and
separate the diaphragm casing (key 4) from the body
(key 1).
2. Remove and inspect the body seal O-ring (key 11)
and the backup ring (key 50).
3. Inspect and replace the orifice (key 5) if necessary.
Lubricate the threads of the replacement orifice with a
good grade of light grease and tighten using 29
to 37 foot-pounds (39 to 50 N•m) of torque.
4. Remove the cotter pin (key 15) if it is necessary to
replace the disk holder assembly (key 13). For a Type
Y690VBM, also inspect the throat seal O-ring (key 31)
by removing the machine screw (key 33). Replace if
necessary. To install a throat seal, place the O-ring on
the machine screw and thread into guide insert (key 18)
to seal.
Note
The disk holder assembly (key 13) is
comprised of the disk and disk holder.
5. Install the disk holder assembly (key 13) and secure
it to the valve stem (key 14) with the cotter pin
(key 15).
6. Install the backup ring (key 48) and body seal O-ring
(key 11) into the body (key 1).
7. Replace the diaphragm casing (key 4) on the body
(key 1) and secure with the cap screws (key 2).
Diaphragm and Spring Case Area
These procedures are for gaining access to the control
spring, diaphragm assembly, valve stem, and stem
WARNING
!!
!!
!

Y690VB Series
5
enough control spring (key 6) force to provide proper
slack to the diaphragm (key 10) and attached parts.
Using a crisscross pattern, finish tightening the spring
case cap screws (key 24) and hex nuts (key 23) to 160
to 190 inch-pounds (18 to 21 N•m) of torque. Then finish
turning the adjusting nut to the desired outlet pressure
setting.
12. Install a replacement closing cap gasket (key 25)
if necessary, and then install the closing cap (key 22).
Type Y690VBM
Key numbers are referenced in figure 4.
1. Remove the closing cap (key 22) and turn the
adjusting nut (key 20) counterclockwise until all com-
pression is removed from the control spring (key 6). If
the only further maintenance is to change the control
spring, skip to step 11.
2. Remove the spring case cap screws (key 24) and
hex nuts (key 23, not shown) and lift off the spring case
assembly (key 3).
3. Remove the diaphragm (key 10) and attached parts
by tilting it so that the pusher post (key 8) slips off the
lever assembly (key 16). To separate the diaphragm
(key 10) from the attached parts, unscrew the dia-
phragm hex nut (key 21). If the only further mainte-
nance is to replace the diaphragm parts, skip to step 8.
4. To replace the lever assembly (key 16), remove the
machine screws (key 17).
5. To replace the valve stem (key 14) or stem seal O-
ring (key 30) perform body area maintenance procedure
steps 1 through 4 and pull the valve stem out of the
guide insert (key 18).
6. Lightly grease the replacement stem seal O-ring
(key 30) and install on the valve stem (key 14). Install
the valve stem by pushing it into the guide insert
(key 18) and perform body area maintenance procedure
steps 5 through 7.
7. Install the lever assembly (key 16) into the valve
stem (key 14) and secure the lever assembly (key 16)
with the machine screws (key 17).
8. Reassemble the diaphragm assembly in the
following order:
€ Pusher post (key 8)
€ Diaphragm head gasket (key 45)
€ Diaphragm head (key 7)
€ Diaphragm (key 10)
€ Diaphragm head (key 7)
€ Washer (key 36)
€ Diaphragm nut (key 38)
Secure with 5 to 6 foot-pounds (7 to 8 N•m) of torque.
9. Install the pusher post (key 8) plus attached dia-
phragm parts onto the lever assembly (key 16).
10. Install the spring case assembly (key 3) and control
spring (key 6) on the diaphragm casing (key 4) so that the
vent assembly (key 26) is correctly oriented, and secure
them with the spring case cap screws (key 24) and hex
nuts (key 23, not shown) to fingertightness only.
11. Install the upper spring seat (key 19) and adjusting
nut (key 20). Turn adjusting nut clockwise until there is
enough control spring (key 6) force to provide proper
slack to the diaphragm (key 10) and attached parts.
Using a crisscross pattern, finish tightening the spring
case cap screws (key 24) and hex nuts (key 23, not
shown) to 160 to 190 inch-pounds (18 to 21 N•m) of
torque. Then finish turning the adjusting nut to the
desired outlet pressure setting.
12. Install a replacement closing cap gasket (key 25)
if necessary, and then install the closing cap (key 22).
To Convert Constructions
The Type Y690VB to the Type Y690VBM:
New parts required: keys 30, 31, and 33
1. Remove pipe plug (key 27) from the diaphragm casing
(key 4).
2. Refer to steps 1 and 3 in the Body area maintenance
section.
3. Insert the throat seal O-ring (key 31, figure 3) and one
machine screw (key 33).
4. Insert the stem seal O-ring (key 30) by following
steps 1 through 7 and 9 through 12 in the Diaphragm and
Spring Case Area Maintenance Section
The Type Y690VBM to the Type Y690VB:
New parts required: key 27
1. Insert pipe plug (key 27) in the diaphragm casing
(key 4).
2. Follow steps 1 through 7 and 9 through 12 in the
Diaphragm and Spring Case Area Maintenance Section
to remove the stem seal O-ring (key 30, figure 3).
Follow steps 1 through 7 of Body Area Maintenance to
remove the throat seal (key 31) and machine screw
(key 33).
Parts Ordering
When corresponding with the Fisher Sales Office or
Sales Representative about this regulator, include the
type number and all other pertinent information
stamped on the nameplate (key 46). Specify the eleven-
character part number when ordering new parts from
the following parts list.

Y690VB Series
6
Table 3. Body Materials and Part Numbers (Key 1)
Parts List
Key Description Part Number
Spare Parts Kit (Stainless steel/Nitrile Construction)
Included are keys 10, 11, 12, 13, 15,
25, 30, 31, 33, and 45 RY690AX0012
1 Body See Table 3
2 Cap Screw
Ductile iron 1C856228992
Stainless steel 18B3456X012
3 Spring Case Assembly
Ductile iron 17B8946X012
Stainless steel 17B8946X022
4 Diaphragm Casing
Ductile iron 47B3063X012
Stainless steel 47B3064X012
5 Orifice
S30300 Stainless steel
1/4-inch (6,4 mm) 1B815135032
1/2-inch (12,7 mm) 1A928835032
6 Spring See table 2
7 Diaphragm Head (2 required)
Stainless steel 17B9723X032
8 Pusher Post Assembly
Stainless steel 17B9742X012
10* Diaphragm
Nitrile 37B9720X012
Fluoroelastomer (FKM) 23B0101X052
11* Body Seal O-Ring
Nitrile (NBR) 1H993806992
Fluoroelastomer (FKM) 1H9938X0012
12* Insert Seal
Nitrile (NBR) 1B885506992
Fluoroelastomer (FKM) 1B8855X0012
13* Disk Assembly
S30300 Stainless steel with
Nitrile (NBR) 1C4248X0202
Fluoroelastomer (FKM) 1C4248X0052
14 Stem 17B3423X012
15* Cotter Pin
Stainless steel 1A866537022
Key Description Part Number
16 Lever Assembly
Stainless steel 1B5375000B2
17 Machine Screw (2 required)
Stainless steel 19A7151X022
18 Guide Insert
Stainless steel 27B4028X022
19 Upper Spring Seat 1A201824092
20 Adjusting Nut 17B9740X012
21 Hex Nut 1A345724122
22 Closing Cap
Standard 1B541644012
Steel 1E422724092
23 Hex Nut, not shown (8 required)
Ductile iron 1A352724122
Stainless steel 1E9440X0302
24 Diaphragm Case Cap Screw (8 required)
Ductile iron 1A352524052
Stainless steel 18B3455X012
25* Closing Cap Gasket 1P753306992
26 Vent Assembly
Spring Case Up (standard) 17A6570X012
Spring Case Down 17A6571X012
27 Pipe Plug
Ductile iron 1A369224492
Stainless steel 1A369235072
28 Lubricant
30* Stem Seal (Type Y690VBM only)
Nitrile 1H2926G0012
Fluoroelastomer (FKM) 1H2926X0022
31* Throat Seal (Type Y690VBM only)
Nitrile 1D682506992
Fluoroelastomer (FKM) 1D6825X0012
33 Machine Screw (Type Y690VBM only) 18A0703X022
36 Washer 18B3440X012
45* Lower Head Gasket 18B3450X012
46 Nameplate
47 Drive Screw (2 required) 1A368228982
50 Backup Ring 18B3446X012
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*Recommended spare part

Y690VB Series
7
Figure 3. Type Y690VB Assembly
B2674_2
B2674_1

Y690VB Series
Figure 4. Type Y690VBM Assembly
B2675

Y690VB Series
April 1999
©Fisher Controls International, Inc.,1999; All Rights Reserved
Fisher,Fisher-Rosemount, andManaging TheProcess Better aremarks ownedby FisherControls International, Inc. or Fisher-RosemountSystems, Inc.
All other marks are the property of their respective owners.
For information, contact Fisher Controls:
Marshalltown, Iowa 50158 USA
28320 Gallardon, France
Sao Paulo 05424 Brazil
Singapore 128461
Thecontentsofthispublicationarepresentedforinformationalpurposesonly,andwhileeveryefforthasbeenmadetoensuretheiraccuracy,theyarenottobeconstruedaswarrantiesorguarantees,expressorimplied,
regarding the products or services described herein or their use or applicability. We reserve the right to modify or improve the designs or specifications of such products at any time without notice.
PrintedinU.S.A.
Errata Sheet
for
Y690VB Series Vacuum Breakers
Form 5465, Feburary 1999
This errata sheet covers changes to the Body Area Maintenance section of the Y690VB Series Vacuum Breakers
Instruction Manual, form 5465. Replace the entire Body Area Maintenance, Diaphragm and Spring Case Area
Maintenance, and To Covert Constructions sections beginning on page 4 with the following:
Body Area
This procedure is for gaining access to the disk
assembly, orifice, and body seal O-ring.All pressure
must be released from the regulator, before the
following steps can be performed.Key numbers are
referenced in figures 3 and 4.
1. To inspect and replace the orifice (key 5) or disk
assembly (key 13), remove the cap screws (key 2) and
separate the diaphragm case assembly (key 4) from
the body (key 1).
2. Removeandinspect thebodyseal O-ring (key11)
andthebackup ring(key50). Replace ifdamaged.
3. Inspect and replace the orifice (key 5) if
necessary.Lightly lubricate the threads of the
replacement orifice. Install with 29 to 37 foot pounds
(39 to 50 N•m) of torque.
• Replace the Body Area Maintenance section on page 4 with the following:
4. To replace the disk holder assembly (key 13),
remove the cotter pin (key 15) if necessary. To inspect
the throat seal (key 31, figure 4) on aTypeY690VBM,
remove the machine screw (key 33). Replace the seal
if necessary.To install, place the seal on the machine
screw and thread into guide insert (key 18).
5. Installthedisk holder assembly(key13) and
secure to the stem (key 14) with the cotter pin (key 15).
6. Install the backup ring (key 50) into the body
(key 1). Next place the body seal O-ring (key 11) into
the body. See figure 5.
7. Replace the diaphragm casing (key 4) on the body
(key 1) and secure with the cap screws (key 2) using 7
to 9 foot pounds (9,5 to 12 N•m) of torque.

Y690VB Series
2
Diaphragm and Spring Case Area
This procedure is for gaining access to the control
spring, diaphragm, and lever assembly stem. All
pressure must be released from the diaphragm case
assembly before performing the following steps.Key
numbers are referenced in figures 3 and 4.
To Change the Control Spring:
1. Remove the closing cap (key 22), and turn the
adjusting nut (key 20) counterclockwise to remove all
compression from the control spring (key 6).
2. Change the control spring to match the desired
springrange.
3. Install the upper spring seat (key 19) and the
adjusting nut (key20), turning clockwise until there is
enoughcontrolspring(key 6) forcetoprovideproper
slack to the diaphragm (key 10). Using a crisscross
pattern, finish tightening the cap screws (key 24) and
hex nuts (key 23, not shown) to 160 to 190 inch-
pounds (22 to 26 N•m) of torque. When finished, turn
the adjusting nut (key 20) to the desired outlet
pressuresetting.
4. Install a replacementclosingcap gasket (key 25),if
necessary, and reinstall the closing cap (key 22).
5. If the spring range was changed, be sure to
change the stamped spring range on the spring case
nameplate.
To Disassemble and Reassemble
Diaphragm Parts:
Use this procedure to gain access to the control spring,
diaphragm assembly, valve stem, and stem O-ring.All
pressuremustbereleasedfromthediaphragmcase
assemblybeforeperformingthesesteps.Keynumbers
arereferencedinfigures3 and 4.
1. Remove the closing cap (key 22) and the adjusting
nut (key 20).
2. Remove the hex nuts (key 23, not shown) and cap
screws (key 24), lift off the spring case assembly
(key 3) and remove the control spring (key 6).
3. Remove the diaphragm (key 10) plus attached
parts by tilting them so that the pusher post (key 8)
• Replace the Diaphragm and Spring Case Area Maintenance section beginning on page 4 with the
following:
slips off the lever assembly (key 16).To separate the
diaphragm assembly (key 10) from the attached parts,
unscrew the diaphragm hex nut (key 21) from the
pusher post (key 8).If the only further maintenance is
to replace the diaphragm parts, skip to step 7.
4. To replace the lever assembly (key 16), remove
the machine screws (key 17).To replace the stem
(key 14) onTypesY690VB andY690VBM or stem seal
(key 30, figure 4) onTypeY690VBM, perform Body
Area Maintenance procedure steps 1 and 4, and pull
the stem (key 14) out of the guide insert (key 18).
5. Install the stem (key 14) into the guide insert
(key18)andperform Body Area Maintenance
procedure steps 5 through 7 as necessary.
6. Install the lever assembly (key 16) into the stem
(key 14) and secure the lever assembly with the
machine screws (key 17).
7. Reassemble the diaphragm parts as follows:
• Pusher post (key 8)
• Diaphragmheadgasket(key 45)
• Diaphragmhead(key7)
• Diaphragm(key10)
• Diaphragmhead(key7)
• Washer (key 36)
• Diaphragm nut (key 21)
Secure using 5 to 6 foot-pounds (7 to 8 N•m) of torque.
8. Install the pusher post (key 8) plus attached
diaphragm parts onto the lever assembly (key 16).
9. Install the spring case (key 3) on the diaphragm
casing (key 4) so that the vent assembly (key 26) is
correctly oriented, and secure with the cap screws
(key 24) and hex nuts (key 23, not shown) fingertight.
10. Install upper spring seat (key 19), the control
spring (key 6), and the adjusting nut (key 20), turning
clockwise until there is enough control spring (key 6)
force to provide proper slack to the diaphragm (key
10). Using a crisscross pattern, finish tightening the
cap screws (key 24) and hex nuts (key 23, not shown)
to 160 to 190 inch-pounds (22 to 26 N•m) of torque.
When finished, turn the adjusting nut to the desired
outletpressuresetting.
11. Install a replacement closing cap gasket (key 25)
if necessary, and then install the closing cap (key 22).

Y690VB Series
3
To Convert Constructions
TheTypeY690VB to the TypeY690VBM:
New parts required:keys 30, 31, and 33
1. Removepipeplug(key27)fromthe diaphragm
casing (key 4).
2. Refer to steps 1 and 4 in the Body Area
Maintenancesection.
3. Insert the throat seal (key 31, figure 4) and machine
screw (key 33, figure 4).
4. Insert the stem seal (key 30, figure 4) by following
steps1 through6and8through11in theDiaphragm and
SpringCaseAreaMaintenancesection.
5. Reassemble following steps 5, 6, and 7 of the Body
AreaMaintenancesection.
• Replace theTo Convert Constructions section on page 5 with the following:
TheTypeY690VBM to the TypeY690VB:
New parts required: key 27
1. Insert pipe plug (key 27) in the diaphragm casing
(key 4).
2. Follow steps 1 through 6 and 8 through 11 in the
Diaphragm and Spring Case Area Maintenance section
to remove the stem seal (key 30, figure 3).
3. Follow steps 1 and 4 of Body Area Maintenance to
remove the throat seal (key 31, figure 4) and machine
screw (key 33, figure 4).
4. Reassemble following steps 5, 6, and 7 of the
Body AreaMaintenance section.
• Add the following figure:
Figure5. ExpandedView of theBody Area
ShowingtheBody Seal O-RIng and Backup Ring Placement
BODY SEAL
O-RING (KEY 11)
BACKUP RING (KEY 50)
BODY (KEY 1)

Y690VB Series
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