Emerson Anderson Greenwood 727 Series User manual

ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
© 2017 Emerson. All Rights Reserved.
Before installation these instructions must be fully read and understood
Emerson.com/FinalControl
TABLE OF CONTENTS
1 General valve description ................................ 2
2 Main valve maintenance................................. 2
3 Pilot maintenance........................................... 7
4 Pilot set pressure adjustment ..................... 15
5 Leak testing assembly ................................. 17
6 Field test instructions................................... 17
7 Repair kits ..................................................... 18
8 Repair tools................................................... 18
9
Piston disk and nozzle sealing face repair .... 20
WARNING
The protection and safety of equipment, property
and personnel depends on the proper operation
of the safety valves described in this manual.
AllEmerson safety valves should be kept in
proper working condition in accordance with the
manufacturer’s written instructions. Periodic
testing and maintenance by the user of this
equipment is essential for reliable and safe valve
operation.
All installation, maintenance, adjustment, repair
and testing performed on safety valves should be
done by qualified technicians having the necessary
skills and training adequate to perform such work.
All applicable Codes and Standards, governing
regulations and authorities should be adhered to
when performing safety valve repair. No repair,
assembly, adjustment or testing performed by
other than Emerson or its authorized assemblers
and representatives shall be covered by the
warranty extended by Emerson to its customers.
The user should use only original, factory supplied
OEM parts in any maintenance or repair activity
involving this product.
SAFETY PRECAUTIONS
When the safety valve is under pressure never place
any part of your body near the outlet of the valve.
The valve outlet and any separate drains should
be piped or vented to a safe location.
Always wear proper safety gear to protect hands,
head, eyes, ears, etc. anytime you are near
pressurized valves.
Never attempt to remove the safety valve from a
system that is pressurized.
Never make adjustments to or perform
maintenance on the safety valve while in service
unless the valve is isolated from the system
pressure. If not properly isolated from the system
pressure, the safety valve may inadvertently open
resulting in serious injury.
Remove the safety valve prior to performing any
pressure testing of the system.
The safety of lives and property often depends on
the proper operation of the safety valve. The valve
must be maintained according to appropriate
instructions and must be periodically tested and
reconditioned to ensure correct function.
This Maintenance Manual is provided as a general
guide for the repair and maintenance of the
safety valves described herein. It is not possible
to describe all configurations or variations with
such equipment. The user is advised to contact
Emerson Valves and Controls or its authorized
assemblers and representatives for assistance
in situations that are not adequately covered or
described in this manual.
Before removing a safety valve for maintenance,
ensure that the system pressure has been fully
depressurized. If an isolation block valve is used
ensure that any trapped fluid between the block
valve and the safety valve is safely vented.
Before disassembling the safety valve ensure that
the valve has been decontaminated from any harmful
gasses or fluids and that it is at a safe temperature
range for handling. Fluids can be trapped in the
dome space of pilot operated safety valves.
Before installation, the Installation and
Operational Safety Instructions should be fully
read andunderstood. These Instructions may
be requested from the factory or are available at
Emerson.com/FinalControl
VCIOM-06013-EN 17/11
Engineering Doc. #05.9040.192 Rev. K
Installation and Maintenance Instructions for
Anderson Greenwood Series 727 Pilot Operated
Safety Relief Valves (POSRV).

2
2.2 Repair
2.2.1
Inspect the nozzle (3) and disk (29) seat
surfaces for nicks or scratches. Restoration
of disk and nozzle seat surfaces should only
require lapping and polishing. If the seat
surfaces are damaged more extensively,
machining may be required. Refer to
Section 9.
2.2.2
Inspect piston rings (11 and 12) for scratches
or galling. If replacement is required refer
to ring kits listed in Section 7. Remove
rings and centralizer springs (21 and 22).
Discard rings and springs. Assemble
new rings and centralizers on piston.
Following the instructions supplied
in each kit. If piston ring expanders
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
2 MAIN VALVE MAINTENANCE
2.1 Disassembly
(Refer to Figures 1 thru 3A)
2.1.1 Note: for ease of repair, the tools and
repair kits specified in Section 7 and
Section 8 should be used.
2.1.2 Use a
11
/
16” wrench to remove all supply
tubing and set aside. Disconnect tubing
from unloader to outlet flange (See note 1) .
If the field test option is installed, remove
both shuttle check valves, related tubing
and fittings and set aside.
2.1.3
Remove blowdown hand valve if one is
installed on the pilot. Use a ¼” allen wrench
to remove pilot retaining screws and pilot
from main valve mounting block and set
aside.
On the 6 x 8 and 8 x 10 valves, the mounting
block will be removed along with its pilot.
Clean off all gasket residue where applicable
being careful not to damage surfaces.
2.1.4 Reposition main valve with cap (2) up.
Remove cap nuts (7). The compressed dome
spring (10) should raise the cap off the valve
body. Remove the cap (2). If the cap appears
stuck to the valve body, free it by tapping
around the cap edge with a brass hammer
or by wedging a large bladed screw driver
between cap and body to free cap.
Should the loosened cap still not rise,
proceed with caution. The spring loaded
2.1.5 Remove piston (4) with disk (29). For sizes
6 x 8 and 8 x 10, a ½-13 UNC eye bolt can
be threaded into back of piston to aid in
removal. The weight of 6” and 8” pistons
may require use of a lift assist device.
Protect disk seat face from damage.
(SeeNote 2)
2.1.6 Before removing liner (5), remove and
discard compacted liner seal (13) being
careful not to damage metal surfaces.
Remove liner (5).
2.1.7
Use only a 12 point socket to remove
nozzle retaining screws (9), and spring
washers (23). To remove nozzle (3),
reinstall two screws 180 degrees apart
without the spring washers. Tap lightly on
screws and drive nozzle (3) free of seal (15).
Remove screws, nozzle (3), nozzle seal (15)
and extrusion ring (14). Discard screws (9),
washers (23) and nozzle seal (15). Under no
condition reuse items 9, 23, and 15.
NOTE
1. If valve is not equipped with an unloader contact
factory for instructions (refertoFigure 1).
2. The disk cannot be disassembled from the 2”, 3”
and 4” valve size piston. The 6” and 8” size disk can
be removed for replacement or relapping. Loosen
three disk assembly retaining screws located inside
piston at spring stop. Hold piston and unscrew disk
assembly with strap wrench.
1 GENERAL VALVE DESCRIPTION
1.1 Operation
The Series 727 Pilot Operated Safety Valve
uses the principle of loading the larger area of
a differential area piston with line pressure to
hold the piston closed up to set pressure. On
rising system pressure, the pilot actuates at set
pressure, venting the small volume of steam
in the dome of the unloader. The unloader
(seeNote 1) is connected directly to the main
valve dome chamber and allows the pressure
to vent into the outlet of the main valve. When
dome pressure is reduced to 40% of system
pressure, the main valve disk lifts off the nozzle
seat, thereby venting system pressure through
the outlet.
When system pressure drops by 5 to 7% of set,
the pilot closes, forcing the reseat piston off its
seat, allowing system pressure to re-enter the
pilot and close the unloader. Recharging of the
main valve dome occurs through the hole in the
main valve piston causing the disk to reseat on
the nozzle.
When operating below set pressure, the inlet
and main valve dome pressures are equal so
that the seating force on the main valve seat is
equal to the system pressure times the seating
area. Since the seat load increases with system
pressure, the main valve maintains premium
seat tightness up to set pressure.
damper may be stuck in the piston and
could suddenly release after the cap is
removed.
Remove damper (8), dome spring (10)
and filter assembly (19). Filter may be
removed by grabbing sleeve with pliers.
Set filter assembly aside for cleaning and
inspection. Reuse if not damaged. Remove
and discard seal (20) at filter port on both
cap and body. Do not remove unloader
(if valve is equipped with one) unless it
leaks. Remove pipe plug (18) in cap (2)
(See detailA in Figure 2) and remove drain
plunger (17) and spring (16) if valve is so
equipped (see detail A in Figure 2).
described in Section 8 are not available,
both rings can be hand installed on the
piston. Carefully expand correct ring over
piston O.D. Place brass shim stock under
ring gap end to prevent scratching piston.
Slide ring into groove.
2.2.3 Inspect liner (5) interior for damage.
Replace liner if damaged.

3
2.3 Assembly
Refer to Section 7 for repair kits and Section 8 for
repair tools.
2.3.1 Important: before assembly, thoroughly
clean all valve parts with oil free solvent
and dry, paying particular attention to all
sealing surfaces. Do not bead or sand
blast. Check both damper and nozzle
for matching orifice “letter” designators
before assembling.
2.3.2 Install extrusion ring (14) (with radius
edge into flange corner), followed by new
nozzle seal (15) and then nozzle (3) (see
detail C in Figure 2). Lightly secure nozzle
(3) with new retaining screws (9) and new
belleville washers (23) (See detail B in
Figure 2 for washer stack orientation).
Use a 12 point socket to tighten screws
in a clockwise pattern, one revolution
per screw, until all screws are fully
seated. This procedure will ensure proper
compression of new nozzle seal. Do not
alternately tighten screws as this method
could cause seal failure.
2.3.3 Stand valve on its outlet flange; install
liner (5) in valve body. Lubricate 45E step
in liner with silicone grease.
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
NOTE
3. The unloader piston is a two piece unit that cannot
be disassembled.
Unloader
Pilot
Output
Radial hole
Input
Main valve 2” thru 4” size valve
Dome
(selfdraining)
Supply
(selfdraining)
FIGURE 12.2.4 If the unloader assembly requires service,
disassemble by clamping the unloader body
in a steel jawed vise and unscrew the hex
head bushing with a 12” crescent wrench.
Remove and discard the seal. Remove
unloader piston from body (See Note3).
See Section 7, repair kits, for seal
replacement information. The unloader
piston and bushing seat surfaces may
be restored by lapping and polishing.
Iftheseating surfaces are damaged more
extensively, machining may be required.
Refer to Section 9. Reassemble, using
theinstructions in the repair kit.
2.2.5
The field test option on a valve,
(seeFigure3, views B and D) will not need
to be repaired unless steam was detected
leaking from the field test port. The field
test option consists of a dome shuttle check
valve, inlet shuttle check valve, field test port
and assorted tubing and fittings (seeFigure
3 and 7). Repair of the shuttle check valves
consists of replacing the internal PTFE
O-rings. (See Section 7, Repair kits.)
Disassemble shuttle check valve by
clamping the body in a vise to remove the
⅞” hex bushing. Reassemble using the
instructions in the repair kit.
2.3.4 If a piston installation sleeve is used,
(see Section 8.2 for details) place sleeve
on top of liner. Lubricate I.D. of sleeve
with silicone grease. Wipe both piston
and nozzle sealing surfaces with a clean
cloth or rag. Insert piston into sleeve to
compress rings with radial hole in
piston
toward valve inlet (refer to Figure1)
. Insert
and center a wooden or plastic dowel
into piston and lightly tap piston into
liner approximately half way. Remove
installation sleeve and force piston down
to nozzle. Install spring (10), damper (8)
and liner seal (13). Do not damage seal.

4
19 20
16
17
18
3
15
14
29 412
11 31
21 22
30
29
923 3 4 10 11 5 1 12 413 7 6
21 22
2
18
25 28 24 26
27
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
Detail B
Belleville stack orientation
before installation
Detail C
Radial
hole
Inlet
Outlet
FIGURE 2
See detail E
for6”and 8”
piston
See detail D
See detail A
See detail B
See detail C
Detail A
PARTS
Item Description
1Body
2Cap
3Nozzle
4Piston
5Liner
6Stud
7Nut
8Piston damper
9Retainer screw
10 Dome spring
11 Damper ring
12 Piston seal ring
13 Liner seal
14 Seal extrusion ring
15 Nozzle seal
16 Drain spring
17 Drain plunger
18 Pipe plug
19 Filter assembly
20 Seal
21 Centralizer spring
22 Centralizer spring
23 Belleville washer
24 Body, unloader
25 Bushing, unloader
26 Piston, unloader
27 Nipple, unloader
28 Seal, unloader
29 Disk
30 Bolt, disk retainer
31 Screw, disk retainer
To pilot
To valve outlet
To main valve cap
Detail D
Side view
Detail E
6” and 8” piston
NOTE
Valve may not be equipped with drain plunger
assembly depending on date of production.

5
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
Pilot valve
Unloader valve
Dome shuttle
Dome tube
(selfdraining)
Inlet shuttle
Lifting lug
Main valve
Outlet
Inlet
Supply tube
(selfdraining)
2” and 3” valve with field test accessory
Outlet
FIGURE 3
Pilot valve
Unloader valve
Dome tube
(selfdraining)
Lifting lug
Main valve
Supply tube
(selfdraining)
4” valve without field test accessory
Inlet

6
¼ 9 ⅝ 150
5
/
16 18 ¾250
⅜31 ⅞378
7
/
16 50 1 (8” 150/300 CL) 405
½75 1 (8” 600 CL) 450
9
/
16 110
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
Outlet
Inlet
Pilot valve
Dome tube
(selfdraining)
Drain port
Vent stack
Lifting lug
Unloader valve
Main valve
Supply tube
(self draining)
Outlet
FIGURE 3A
6” and 8” valve
Field test port
Pilot valve
Dome shuttle
Drain port
Vent stack
Lifting lug
Unloader valve
Main valve
Inlet shuttle
Valve sizes 6 x 8, 8 x 10 without field test option
Valve sizes 6 x 8, 8 x 10 with field test option
TABLE 1 - TORQUE VALUES FOR VALVE ASSEMBLY (foot-pounds)
Bolt size Carbon steel Bolt size Carbon steel
Inlet

7
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
3 PILOT MAINTENANCE
3.1 Pilot disassembly
(Refer to Figure 4A style pilot)
To facilitate assembly, place all parts in an
orderly arrangement so the parts can be
assembled in the proper sequence.
Before beginning disassembly, have the
correct tools and repair kits specified in
sections 7 and 8 available.
3.1.1 Remove vent (24) and manual
blowdown hand valve if one is installed
(refer to Figure 7).
3.1.2 Use a 1
½
” wrench to hold bonnet and
remove bonnet cap (3). Use a depth
micrometer or calipers to measure
and record the distance from top of
adjusting screw to top of pilot body. This
measurement will be used in 3.2.1 step
“O”. Loosen locknut (6) and back out
adjusting screw (5) to relieve pilot spring
compression.
3.1.3
Remove bonnet (2), being careful to catch
spring (7) and spring washers (4 and 26)
when they disengage. Turn pilot upside
down on a soft surface to remove remaining
internal parts from upper half of body.
Discard disk (9). Remove nozzle (10) and
seal (11) and discard.
3.1.4 Loosen safety screw (20) on locknut (18)
with a
5
/
32” allen wrench. Loosen locknut
(18) and blowdown adjustment screw
assembly. Remove assembly from body.
Remove shims (25).
3.1.5 Place reseat seat (12) in a vise. Using an
11
/
16” wrench on the blowdown adjustment
screw (21), loosen and remove seat.
Remove reseat piston (15) located inside.
Discard both reseat seat (12) and reseat
piston (15).
3.1.6 Remove tube fitting from blowdown
adjustment screw (21), and then remove
locknut (18), reseat bushing (16) and
Grafoil®gaskets. Discard gaskets.
3.2 Pilot assembly
(Refer to Figure 4A stylepilot)
The lapped and polished metal seats are the key
to proper pilot operation and care must be taken
in handling these components. Before assembly,
thoroughly clean all parts with an oil free solvent
and dry. This is important for the nozzle seat
area. Do not bead blast or sand.
Examine pilot parts and remove any oxide build
up with light buffing using a wire brush or wheel.
3.2.1 Assemble pilot in the following order:
A. Insert reseat piston (15) into the
blowdown adjustment screw (21) with
lapped face turned toward internally
threaded opening.
F.
Install a shim stack (25) of approximately
.125 inches thick onto the blowdown
adjustment screw (21). Rotate the reseat
bushing (16) on the screw (21) to lightly
secure the shim stack. Install the assembly
into the lower end of the pilot body cavity
and tighten the bushing (16) securely.
G. Install ¼ NPT pipe plugs in the upper two
ports shown at (22) coated with Jet-Lube
Thick or Thin.
H. Install ½ NPT pipe plug in port shown at
(23) wrapped with PTFE tape. (If optional
manual blowdown hand valve is required,
install it last after mounting the pilot to
body.)
I. Install fitting in the lower “dome” port
for attachment to the pilot test stand and
install fitting in the supply port for testing.
J. Insert spacer rod (13) into the reseat
assembly with large end down before
installing upper guide assembly.
K. Refer to Figure 4A: install disk (9), ball
(27) and spring washer (28) into spindle
(8) and spindle (8) into guide (14) taking
care to keep disk seat clean.
L. Install nozzle (10) and seal (11) into guide
(14) and install complete upper guide
assembly into the upper body cavity.
Note: this is easier with the body turned
on its side.
M. Install lift test dial indicator and special
housing shown in Figure 5A. Check spindle
lift and adjust as described in this Figure
by adding or removing shims.
NOTE
GRAFOIL®is a registered trademark of UCARCarbon.
B. Lubricate reseat seat threads lightly with
Fluorolube to prevent galling.
C. Install reseat seat (12) into the blowdown
adjustment (21) screw. Clamp seat in vise
and securely tighten adjustment screw
with
11
/
16” wrench to seat the metal to
metal seal.
D. Lightly lubricate external threads on
the blowdown adjustment screw with
Fluorolube and install bushing (16), thread
seal (19) and locknut (18) as shown. Leave
the locknut loose. Install thread seal (17)
on reseat bushing (16).
E. Shimming is required as shown at item (25).
Multiple shims are supplied to be used as
required. A shim stack of approximately
.125 inches is required
to initially set the
pilot travel. Shim thicknesses available
are .012, .025, and .063 inches. The shim
stack height may be changed later to
adjust the minimum pilot lift to .010.-.025
inches.
Shim adjustment is explained in
Figure5A.
The shims are C-washers and
can be added or removed as required with
thelower unit assembled.

8
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
3.3 Pilot disassembly
(Refer to Figure 4B and 4C style pilot)
To facilitate assembly, place all parts in an
orderly arrangement so the parts can be
assembled in the proper sequence.
Before beginning disassembly, have the
correct tools and repair kits specified in
sections 7 and 8 available.
3.3.1 Remove vent (24) and Manual blowdown
hand valve (see Figure 7) if installed.
3.3.2 Use a 1
⅛
” wrench to hold bonnet and
remove bonnet cap (3). Use a depth
micrometer or calipers to measure
and record the distance from top
adjusting screw to top of pilot body. This
measurement will be used in 3.4.1 step
“O”. Loosen locknut (6) and back out
adjusting screw (5) to relieve pilot spring
compression.
3.3.3
Remove bonnet (2), being careful to catch
spring (7) and spring washers (4 and 26)
when they disengage. Turn pilot upside
down on a soft surface to remove remaining
internal parts from upper half of body.
Discard disk (9). Remove nozzle (10) and
seal (11) and discard.
3.3.4 Use a 1⅜” wrench on bushing (16) to
remove blowdown adjustment assembly
from pilot body (1). Remove thread
seal (17) and discard. Place bushing
(16) in vise. Remove nut (18). Hold the
3.4 Pilot assembly
(Refer to Figure 4B and 4C style pilot)
The lapped and polished metal seats are the
key to proper pilot operation and care must be
taken in handling these components. Before
assembly, thoroughly clean all parts with oil
free solvent and dry. This is important for the
nozzle seat area. Do not bead blast or sand.
Examine pilot parts and remove any oxide build
up with light buffing using a wire brush or wheel.
3.4.1 Assemble pilot in the following order:
A.
Insert reseat piston (15) into the blowdown
adjustment screw (21) with lapped face
turned toward internally threaded opening.
B. Lubricate reseat seat threads lightly with
Fluorolube to prevent galling.
C. Install reseat seat (12) into the blowdown
adjustment (21) screw. Clamp seat in vise
and securely tighten adjustment screw
with
11
/
16” wrench to seat the metal to
metal seal.
D. Refer to Figure 4C: preassemble the
blowdown adjustment unit as follows:
1. Insert blowdown adjustment screw (21)
into bushing (16).
2. Slide new packing (19) on adjustment
screw (21) and press into bushing (16)
using seal retainer (41).
3. Lubricate threads on bushing (16) and
nut (18) with Fluorolube and place
bushing in vise. Install and tighten nut
to compress packing (19) and force
seal retainer (41) metal to metal with
bushing and nut. Remove nut (18) and
set aside. Remove seal retainer (41).
N. After setting minimum pilot lift to the
specified range (.010”-.025”), and before
removing the dial indicator, adjust the
blowdown adjustment screw in until pilot
lift is approximately .050”. This will put
the blowdown near the normal range for
final adjustment. Tighten locknut (18).
O. After setting pilot lift, remove the special
housing and dial indicator and install
bonnet spring washer (29), spring (7),
spring washers (26) and (4), bonnet (2),
adjustment screw (5), and locknut (6).
Apply a very light coat of Fluorolube
only to threads on spring bonnet before
assembly. Tighten bonnet securely to
completely seat the nozzle gasket. Turn
adjusting screw (5) in until top of screw is
the same distance from top of pilot body
as measured in step 3.1.2. This will get
the pilot reasonably close to set pressure
to facilitate final adjustment on the test
stand.
P. Install vent (24) in pilot body.
Q. The pilot is now ready to be adjusted
for set pressure and reseat pressure.
See Figure 6 for requirements of pilot
test stand. See Section 4 for setting
procedure.
R. After pilot is adjusted, install cap (3) and
safety screw (20) into locknut (18). Secure
with sealing wire from cap (3) through
hole in safety screw (20).
adjustment screw (21) with an
11
/
16”
wrench and remove tube fitting from
blowdown adjustment screw (21).
Unscrew adjustment sleeve (42) from
blowdown adjustment screw (21). Remove
seal retainer (41). Remove adjustment
screw (21) from bushing (16), remove
packing (19) from bushing and discard.
Remove retainer (45) and set aside.
3.3.5 Place reseat seat (12) in a vise. Use a
11
/
16” wrench on the blowdown adjustment
screw (21) to loosen and remove seat.
Remove reseat piston (15) located inside.
Discard both reseat seat (12) and reseat
piston (15).

9
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
E. Shimming is required as shown at
item(25).
Multiple shims are supplied
to be used as required. A shim stack of
approximately .125 inches is required
to initially set the pilot travel. Shim
thicknesses available are .012, .025, and
.063 inches. The shim stack height may be
changed later to adjust the minimum pilot
lift to .010-.025 inches. Shim adjustment
is explained in Figure 5B. The shims
are C-washers and can be added or
removed as required with the lower unit
assembled.
F. Install a shim stack (25) of approximately
.125 inches thick onto the blowdown
adjustment screw (21) on top of the
retainer (25). Rotate the adjustment sleeve
(42) to lightly secure the shim stack. Install
the complete blowdown assembly into
the lower end of the pilot body cavity and
tighten the bushing (16) securely.
I. Install fitting in the lower “dome” port for
attachment to the pilot test stand.
J. Insert spacer rod (13) into the reseat
assembly with large end down before
installing upper guide assembly.
K. Refer to Figure 4B: install disk (9), ball (27)
and spring washer (28) into spindle (8) and
spindle (8) into guide (14) taking care to
keep disk seat clean.
L. Install nozzle (10) and seal (11) into guide
(14) and install complete upper guide
assembly into the upper body cavity.
Note: this is easier with the body turned on
its side.
M.Install lift test dial indicator and special
housing as shown in Figure 5B. Check
spindle lift and adjust as described in the
procedure by adding or removing shims.
N. After setting minimum pilot lift to the
specified range (.010”-.025”), and before
removing the dial indicator, adjust the
blowdown adjustment screw in until pilot
lift is approximately .050”. This will put the
blowdown near the normal range for final
adjustment. Tighten locknut (18).
4. Install pin (43) into seal retainer (41).
Pin must protrude .062” to .067” into
adjustment sleeve (42) pocket. Lightly
coat pocket of seal retainer with
Fluorolube.
5. Install retainer (45) into slots on
bushing (16) and blowdown adjustment
screw (21). Reinstall seal retainer (41)
on blowdown adjustment screw (21).
6. Lubricate threads on adjustment
screw (21). Install left-hand threaded
adjustment sleeve (42) on screw until
sleeve bottoms off inside retainer
pocket.
Check movement of sleeve in pocket
against pin stop. Continue to rotate
until blowdown adjustment screw (21)
and retainer (45) shoulder off against
bushing (16). Lightly coat bottom of
sleeve surface (contact with nut) with
Fluorolube.
7. With bushing in vise, install nut (18)
and tighten. Check rotation of sleeve
(42) with ¾” open-end wrench. Hold
blowdown adjustment screw with
wrench to prevent retainer (45) from
twisting out. Adjustment screw should
move in and out smoothly, stop to stop.
8. Hold body of adjustment screw (21) and
install tube fitting into end and tighten.
Coat threads of tube fitting with Jet
Lube Thick or Thin before installation.
9. Clamp bushing (16) in vise and slightly
loosen nut (18) for final blowdown
adjustment on assembled pilot.
O. After setting pilot lift, remove the special
housing and dial indicator and install
bonnet spring washer (29), spring (7),
spring washers (26) and (4), bonnet (2),
adjustment screw (5), and locknut (6).
Apply a very light coat of Fluorolube only to
threads on spring bonnet before assembly.
Tighten bonnet securely to completely seat
the nozzle gasket. Turn adjusting screw (5)
in until top of screw is the same distance
from top of pilot body as measured in step
3.3.2. This will get the pilot reasonably
close to set pressure to facilitate final
adjustment on the test stand.
P. Install vent (24) in pilot body.
Q. The pilot is now ready to be adjusted for
set pressure and reseat pressure. See
Figure6 for requirements of pilot test
stand. SeeSection 4 for setting procedure.
R. After plot is adjusted, install cap (3) and
safety screw (20) into locknut (18). Secure
with sealing wire from cap (3) through hole
in safety screw (20).
G. Install ¼ NPT pipe plugs in the upper two
ports shown at (22) coated with Jet-Lube
Thick or Thin.
H.
Install ½ NPT pipe plug in port shown
at(23) wrapped with PTFE tape. If optional
manual blowdown hand valve is required,
install it last after mounting of pilot to body.

10
33
2
35
34
36
38
39
40
38
27
9
28
31
32
30
3
5
6
4
7
26
37
8
14
3
5
2
4
7
26
8
10
11
22
12
13
1
25
16
22
15
23
17
19
18
21 20
24
14
6
29
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
FIGURE 4A
Vent
Note washer orientation
Detail A
Sealing wire
See detail A
Dome
Supply
PARTS
Item Description Item Description Item Description
1Body 15 Reseat piston 29 Washer, bonnet
2Bonnet 16 Reseat bushing 30 Lever, gag rod
3Cap 17 Thread seal 31 Bolt
4Upper spring washer 18 Lock nut 32 O-Ring
5Adjusting screw 19 Thread seal 33 Lever
6Hex jam nut 20 Safety screw 34 Spring, torsion
7Spring 21 Blowdown adj. screw 35 Nut, gland
8Spindle 22 Pipe plug ¼ NPT 36 Pin, roll
9Disk 23 Pipe plug ½ NPT 37 Cam
10 Nozzle 24 Vent 38 O-Ring
11 Nozzle seal 25 Shim 39 Washer, lock
12 Reseat seat 26 Lower spring washer 40 Bolt, ¼-28 x ⅜
13 Spacer 27 Ball
14 Case guide 28 Washer, pilot
Original design pilot assembly

11
33
2
35
34
36
38
39
40
38
31
32
30
3
5
6
4
7
26
37
8
14
27
9
28
3
5
2
4
7
26
8
10
11
22
12
13
1
45
25
16
22
15
23
17
19
18
14
6
29
24
41
42
44
21
20
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
FIGURE 4B
PARTS
Item Description Item Description Item Description
1Body 16 Reseat bushing 31 Bolt
2Bonnet 17 Thread seal 32 O-Ring
3Cap 18 Lock nut 33 Lever
4Upper spring washer 19 Thread seal 34 Spring, torsion
5Adjusting screw 20 Safety screw 35 Nut, gland
6Hex jam nut 21 Blowdown adj. screw 36 Pin, roll
7Spring 22 Pipe plug ¼ npt 37 Cam
8Spindle 23 Pipe plug ½ npt 38 O-Ring
9Disk 24 Vent 39 Washer, lock
10 Nozzle 25 Shim 40 Bolt, ¼-28 x ⅜
11 Nozzle seal 26 Lower spring washer 41 Seal retainer
12 Reseat seat 27 Ball 42 Adjustment sleeve
13 Spacer 28 Washer, pilot 43 Pin
14 Case guide 29 Washer, bonnet 44 Fitting - special
15 Reseat piston 30 Lever, gag rod 45 Retainer
Sealing wire
See detail A
Dome
port
Vent
Supply port
Install in hole
nearest this view
Second generation design pilot assembly
beginningwithSerial No: 92-10501
Note washer orientation
Detail A

12
15
45
16
18
42
12
21
25
19
41
43
44
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
FIGURE 4C Blowdown adjustment pre-assembly
Shim placement

13
06.0925.003 .063
06.0925.002 .025
06.0925.001 .012
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
1. Install pilot on test stand.
2. With pilot assembled as shown, without
spring, spring washer and adjusting
screw, back blowdown adjustment stem
all the way out (downward position). Full
counterclockwise position.
3. Pressurize inlet to 25 psig and measure
lift of spindle. Lift must be .010 to .025.
Physically cycle dial indicator up and down
to measure pilot lift.
4. Add shims between bushing and blowdown
stem to obtain correct lift. To add shims,
the reseat assembly must be removed from
body. Shims are “C” washers, therefore
disassembly of lower unit is not required.
Snap shims on or off and combine as
required to meet lift requirements. Measure
shim thickness before removal so thickness
adjustments can be made as required.
Movable stem
2” Dial indicator
0.100 Stem travel
1.00 Stem extension
ø.375 Shank
¼” Set screw
Housing for lift test part
number 06.1330.001
Spindle
Reseat assembly
Dome port
Add shims here to obtain
proper lift
Bushing
Blowdown adjustment stem
Supply port (air in)
.010
.025 Lift
FIGURE 5A
Shim Thickness

14
06.0925.003 .063
06.0925.002 .025
06.0925.001 .012
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
1. Install pilot on test stand.
2. With pilot assembled as shown, without
spring, spring washer and adjusting
screw, rotate blowdown adjustment sleeve
counterclockwise to place the adjustment
screw in the full down position.
3. Pressurize inlet to 25 psig and measure
lift of spindle. Lift must be .010 to .025.
Physically cycle dial indicator up and down
to measure pilot lift.
4. If required, add shims between bushing and
blowdown stem to obtain correct lift. To add
shims, the blowdown assembly must be
removed from body. Shims are “C” washers,
therefore disassembly of lower unit is not
required. Snap shims on or off and combine
as required to meet lift requirements.
Measure shim thickness before removal
so thickness adjustments can be made as
required.
Shim Thickness Movable stem
2” Dial indicator
0.100Stem travel
1.00Stem extension
ø.375 Shank
¼” Set screw
Housing for lift test part
number 06.1330.001
Spindle
Adjustment screw and
reseat assembly
Note: moves axially and
does not rotate.
Dome port
If necessary add shims here
to obtain proper lift (stack on
top of retainer)
Wrench here for removal
or installing blowdown
assembly
Rotational blowdown
adjustment stem
Supply port (air in)
Note: retainer
prevents adjustment
screw from rotating
.010
.025 Lift
FIGURE 5B
Warning: use a backup
wrench on this fitting.
Donotallow it to rotate
when connecting fitting.

15
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
4 PILOT SET PRESSURE ADJUSTMENT
4.1 General
Two adjustments are provided; one for
adjusting the set pressure and one for adjusting
the reseat pressure.
4.2 Definitions
4.2.1 Definitions of test pressures:
4.2.1.1 Set pressure
The pressure at which the pilot reduces
the pressure at the dome connection to
50% or less of supply. Also referred to
as nameplate set.
4.2.1.2 Cold differential test pressure
The set and reseat pressure the pilot is
adjusted to actuate on the test stand that
includes corrections for high temperature
service conditions. This pressure is also
included on the nameplate.
4.2.1.3 Cracking pressure
The point at which the pilot first begins
to leak on increasing pressure.
4.2.1.4 Reseating pressure
The pressure at which the pilot valve
closes to restore pressure at the dome
connection. This pressure will be 50% or
more of the pressure at the pilot supply
pressure port at the time of reseat.
4.2.1.5 Dome pressure
The pressure at the dome port
connection on the pilot.
4.2.1.6 Blowdown
The difference between the set pressure
and the reseat pressure, expressed as a
percent of set pressure, or in psig.
4.3 Test procedures
(Refer to Figure 6 for test set-up)
4.3.1 General
The ASME Section VIII Pressure Vessel
Code requires that pilots on pilot operated
valves for steam service be set using
steam except for those pilots which have
set pressures beyond the capability of
the test facility. For those pilots, the test
medium may be air.
The air set pressure is the cold differential
test pressure and is so indicated on the
nameplate (Refer to Figures 8 and 9). This
pressure will be higher than
nameplate
set. Refer to 4.5 performance requirements
for correct setting values.
4.3.1.1 Test set up
Install the pilot valve on the test drum
similar to that shown in Figure 6. The
“dome” connection is a blind connection
with a pressure gauge to indicate the
dome pressure reduction achieved
while the pilot actuates at set pressure.
4.4 Pilot performance
4.4.1
Slowly increase the pressure at the inlet
port until leakage is detected at the pilot
exhaust port. Check for leakage
with a
bubble tube tester for air set or a metal rod
for steam set. The presence of condensate
on the rod indicates a leakage. This
pressure shall be recorded as the cracking
pressure.
4.4.2 Further increase the pressure at the inlet
port until the pilot actuates or “pops”.
This pressure shall be recorded as the
set pressure.
4.4.3 Shut off the inlet pressure to the test
accumulator and bleed inlet pressure to
allow the pilot to reseat. This pressure
shall be recorded as the reseat pressure.
Check the valve for leakage at the exhaust
port with a bubble tube tester for air set or
a metal rod for steam set.
4.3.1.3 Reseat adjustment
(Refer to Figure 4A style pilot only)
Remove safety screw (20). Loosen
locknut (18) to adjust the reseat
pressure. It is not necessary to loosen
the compression fitting on the supply
port for the adjustment screw to rotate.
Hold locknut (18) and use the wrench
flats (
9
/
16”) on the blowdown adjustment
screw to adjust it in or out. Move in
45E (⅛ th turn) increments. Moving the
screw in shortens blowdown and out
increases blowdown.
Note: if the compression fitting must be
loosened under pressure, care should
be taken not to over-loosen and allow
excessive leakage.
4.3.1.4 Reseat adjustment
(Refer to Figure 4B style pilot)
Loosen safety screw (20). Use a ¾” open
end wrench on the adjustment sleeve (42)
to adjust the reseat pressure. Rotating
the adjustment sleeve clockwise shortens
blowdown; counter clockwise increases
blowdown.
4.3.1.5 Performance check - relieving pressure
Cycle the pilot a minimum of three times
after the adjustment to make sure the
pop and reseat pressures are consistent.
Increase and decrease the pressure
slowly to obtain an accurate reading and
to expose any erratic performance.
4.3.1.2 Set pressure adjustment
(Refer to Figure 4A and 4B)
Remove cap (3) and loosen locknut (6).
Adjust the spring adjusting screw (5) to
obtain the correct set pressure. Clockwise
rotation will increase the set pressure.
Note: tighten the locknut after each
adjustment is made.

16
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
4.5 Performance requirements
Cold differential set is the increase in specified set to compensate for the change in spring force
with increased temperature. Cold differential set is the test bench setting pressure. Specified set
is the nameplate set pressure.
4.5.1 Cold differential set
NOTE
1. ± 3% or 2 psig is ASME specified performance tolerance. AG setting tolerance is:
Above 70 psig + 2% - 0%
70 psig and below + 1 psig - 0 psig
Set pressure adjustment (inside cap)
(turnin to increase set pressure; turn
out to decrease set pressure)
Pilot exhaust vent
Supply valve
This valve must be closed when setting
pilots above 600 psig
Dome pressure should be zero when pilot is
actuated and no gas flow is detected at pilot vent.
Air supply
Filter Accumulator vent valve
Mounting stub
Pipe
nipples
Accumulator
(approx. ¼ cu. ft.)
Part no. TD-1
300 CC
1000 CC
Condensate drain
Coupling Blowdown adjustment (turn in to
shorten; turn out to increase)
Flexible supply hose
Pilot isolation valve
FIGURE 6
4.4.4 Repeat paragraphs 4.4.1 through 4.4.3 a
minimum of three times. The cracking
pressure, set pressure and reseat pressure
shall be within the limits specified in the
applicable performance requirements for
three consecutive cycles. The valve action
shall be consistent.
4.4.5 Slowly increase the inlet pressure until
the crack test pressure specified in the
applicable valve specification sheet is
reached. Maintain this pressure for one
minute and check for leakage at the
exhaust port with a bubble tube tester for
air set or a metal rod for steam set.
4.4.6
Tighten locknut (18) and reinstall safety
screw (20) and tighten. Replace cap (3)
and tighten.
Operating temperature Cold differential set
Below 295°F 100% of specified set
296°F to 400°F 101% of specified set
401°F to 800°F 103% of specified set
4.5.2 Set pressure tolerance (1)
Above 70 psig ± 3% of specified cold differential set for air set or
± 3% of the specified set for steam set
70 psig and below ± 2 psig
4.5.3 Crack pressure
50 psig to 1200 psig 90% +10%/-0% of specified cold differential set for air set or
90% +10%/-0% of the specified set for steam set
4.5.4 Reseat pressure
50 psig to 1200 psig 94% ± 1% of specified cold differential set for air set or
94% ± 1% of the specified set for steam set
4.5.5 Leakage test
Air
No leakage for one minute at pressure below the crack pressure.
Steam
No visible condensate on metal rod at pilot outlet for 10 seconds when tested 3 minutes
after reseat.

17
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
5 LEAK TESTING ASSEMBLY
5.1 Air
The main valve with pilot assembled to it and
all tubing connections should be leak tested for
external leaks using a pressure equal to 90% of
set. Air at ambient temperature shall be used
unless otherwise specified.
WARNING
Do not cycle main valve on air. The opening and
closing forces could damage the internal components.
5.2 Steam
Apply steam pressure to the inlet equal to 90% of
the set pressure. Check for visual leakage at the
main valve nozzle and seat, piston seal, cap seal,
unloader fittings and other pressure and tubing
connections. Tighten bolts or fittings as required.
If a leak is observed between the cap and body,
be sure the cap has been assembled squarely
against the body before tightening cap bolts.
6 FIELD TEST INSTRUCTIONS
6.1 Hot set pressure verification
If the valve is equipped with the optional field test
accessory, an accurate check of the set pressure
can be made after the valve has been in service a
minimum of 2 hours. System pressure should be
90% or less of set pressure. The main valve will
not cycle during this procedure but will operate
should system relief be required during the test.
6.1.1 Test procedure
(Refer to Figure 7)
A. Connect test gas bottle to field test port.
B. Close vent valve.
C. Slowly open supply pressure valve on test
gas bottle.
D. Increase pressure slowly to pilot until
pilot pops. Observe pressure at pop.
Repeat test as required until three
consistent pops are observed.
E. To remove test set-up, close supply
pressure valve and open vent valve.
F. The pop pressure measured is the hot
set pressure and should be within the
nameplate set pressure tolerance. These
tolerances are ± 2 psig, below 70psig and
± 3% above 70 psig.
6.2 Cold set pressure verification
Before the valve is installed or immediately after
bringing the valve on line and before the valve
reaches normal operating temperature, the set
pressure can be checked using test procedure
6.1.1 except that the pressure read on the test
gage will be the cold differential test pressure on
the nameplate. This pressure is established based
on the specified temperature during operation and
will be greater than the nameplate set pressure
to compensate for the reduction in spring force
due to temperature. The set pressure tolerances
listed in 6.1.1 F apply.
Manual blowdown valve (option)
Lift lever (option)
Field test injection port (¼-NPT male elbow
not supplied)
Flex hose
Vent valve
Nitrogen bottle
Supply
pressure valve
Unloader
(4 x 6 valve shown)
FIGURE 7

18
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
7 REPAIR KITS
The kits listed below are available from stock. To order kits specify the base number and select
the last three digits from the following tables. To make sure correct kits are purchased the order
should specify the valve model and serial number.
Kit base number: 06-1237-XXX _
8 REPAIR TOOLS
8.1 Special
The tools listed below are available by special order. Contact Anderson Greenwood’s Sales
Department for price and delivery.
1. 2” Piston ring expander
Snap-on tools # PRS-8
AG part no. 05-1185-054
2. 3” and 4” Piston ring expander
Snap-on tools # PRS-10
AG part no. 05-1185-055
3. 6” Piston ring expander
Diesel supply Co.
4. 8” Piston ring expander
Diesel supply Co.
7.1 MAIN VALVE
Kit and contents 2 x 3 3 x 4 4 x 6 6 x 8 8 x 10
Seal kit: liner seal, -003 -005 -007 -009 -011
nozzle seal, filter
assembly, filter-seal,
Belleville washers,
nozzle retaining screws
Ring kit: damper ring -020 -021 -022 -023 -024
piston ring, and
centralizer springs
7.2 PILOT
Kit and contents All pressures
Seal kit: nozzle -001
seal, thread seals
packing seal
Seat kit: disk, nozzle, -002
reseat seat, reseat
piston, ball and washer
7.3 UNLOADER: FOR 4X6, 6X8, AND 8X10
Kit and contents All pressures
Seal -013
7.4 UNLOADER: FOR 2X3 AND 3X4
Kit and contents All pressures
Seal -015
7.5 FIELD TEST SHUTTLE CHECK VALVES
Kit and contents All pressures
Seal -014

19
10°
30°
15°
.300
B Ø
A Ø
C Ø
D Ø
FG
.060
2” 2.700 2.495 2.550 2.882 3.075 .030 1.25
2.493 2.540 2.880 3.065
3” 3.750 3.495 3.597 4.138 4.325 .060 1.88
3.493 3.587 4.136 4.315
4” 5.188 4.870 4.970 5.267 5.602 .060 1.50
4.868 4.960 5.265 5.592
6” 8.340 7.995 8.170 8.722 9.067 .100 1.56
7.993 8.160 8.720 9.057
8” 10.940 10.485 10.770 11.222 11.555 .150 2.00
10.483 10.760 11.220 11.545
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
8.2 Piston installation sleeve
.015 R Typ.
.03 R Optional
Size A B C D E F G
Tolerance: Hundredths = ± .03
Thousandths = ± .010
Angles = ± 10
8.3 Special
1. 12 point sockets, nozzle retaining screw
removal/installation
¼” for 2 x 3, 3 x 4
5
/
16” for 4 x 6
⅜” for 6 x 8, 8 x 10
2.
11
/
16” Open end wrench
3. ⅝” Open end wrench
4.
5
/
32” Allen wrench
5. ¼” Allen wrench
6. Brass hammer
7. 12” Crescent wrench
8. Wood or plastic dowel rod
9. Optional tools
- Air impact tool w/socket set thru
17
/
16”
- Over head crane or hoist
- Strap wrench
10. Housing-pilot lift indicator
AG part no. 06-1330-001
11. 2” Dial indicator/.001 increments
.100 stem travel/1.00 stem extension
12. Brass shim stock
8.4 Lubricant/sealants
1. Dow Corning-Silicone-33 grease (or
equivalent)
2. Jet-Lube “Thick or Thin”
3. Hooker Chemical “Fluorolube” LG-160
FIGURE 8 FIGURE 9
Earlier design: nameplate only on pilot
Pilot
Main valve
Present design: nameplate only on pilot and
mainvalve

20
-Y-
A
B
1
-X-
“A” 3.54 4.89 5.305 7.72 11.13
“B” 0.88 0.89 1.310 1.64 2.10
2 x 3 06.1595.001
3 x 4 06.1595.002
4 x 6 06.1595.003
6 x 8 06.1595.004
8 x 10 06.1595.005
ANDERSON GREENWOOD SERIES 727 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
9 PISTON DISK AND NOZZLE SEALING FACE
REPAIR
The piston disk and nozzle seat faces are
manufactured to close tolerances and finishes.
Care must be exercised in reworking both
mating surfaces to insure a tight seat after
main valve assembly.
Refacing of both parts is limited to the “mated”
minimum heights and tolerances listed in
Table 2 shown in Figure 10.
9.1 Lapping
The finer points of lapping should be considered
a mechanical art. The ability of the average
repair person to produce a good lapped seat will
require practice. No effort has been made in this
manual to establish an exact lapping procedure.
However, it is very important to insure that the
laps you are using (whetherdonut laps or flat
lapping plates) are flat within 2 light bands.
Otherwise an uneven surface will be transferred
to the seat sealing area.
The following items are required when lapping
a piston disk or nozzle.
A. One flat lap per valve (see list below.)
B. Clover compound “C”, 220 grit medium, to
remove, groves, pits, and dents.
C. Clover compound, “1A,” 320 grit, very fine,
for general smoothing of seats.
D. Clover compound, “3A”, 500 grit, extremely
fine, for general smoothing of seats.
E. Clover compound, “6A”, 1000 grit, micro
fine, for final finishing of seat.
F Cotton rags, clean and lint free.
Before lapping, chamber the leading edge
of both disk and nozzle with a ring grade of
sandpaper. This will break the inner and outer
edges and remove any small metal particles
that might be attached to the sharp corner
surfaces.
9.1.1 LAP PART NUMBERS FOR ORDERING LAPS
Valve size Part numbers
9.2 Remachining disk and nozzle
Machining of the piston chamfer to maintain
the minimum “B” dimension is permissible
until the minimum “A” is achieved. When
this occurs, no further machining is possible
and either one or both components must be
replaced.
WARNING
Mated heights less than the dimensions given
in Table 2 will result in seal ring damage and
potential failure of main valve function.
TABLE 2 - MINIMUM REMACHINED PISTON AND NOZZLE DIMENSIONS
Valve size 2x3 3x4 4x6 6x8 8x10
Nozzle
Typical
piston
FIGURE 10
1
NOTES
Disk face: .003 Y
Nozzle face: // .003 X