cashco 8310HP-1+8 Instruction manual

MODELS 8310HP DIFFERENTIAL
(1+6 and 1+8 ) PRESSURE REDUCING REGULATORS
SECTION l
l. DESCRIPTION AND SCOPE
The Models 8310HP-1+6 and 8310HP-1+8 are differential reducing regulators used to control differential pressure between
downstream (outlet or P2) pressure and a loading (PLoad) pressure to the spring chamber. Available in sizes 1-1/2" (DN40), 2"
(DN50), 2-1/2" (DN65), 3" (DN80) and 4" (DN100). Widely applied in steam atomization systems using heavy oil (Nos. 3-6,
Bunker C) to fuel burners. Refer to Technical Bulletin 8310HP-DIFF-TB for design conditions and selection recommendations.
SECTION II
II. INSTALLATION
IOM-8310HP-DIFF
06/16
7. Clean the piping of all foreign material including chips,
welding scale, oil, grease and dirt before installing the
regulator. Strainers are recommended.
8. In placing thread sealant on pipe ends prior to
engagement, ensure that excess material is removed
and not allowed to enter the regulator upon start-up.
9. Flow Direction: Install so the flow direction matches
the arrow cast on the body. Install an external sensing
line (1/2" O.D. (DN15) tubing minimum) from the 3/8"
(DN10) NPT connection in needle valve (39) to a point
downstream, preferably at gauge location.
10. Install oil loading pressure sensing line to spring chamber
(13) connection.
11. For long operational life with minimum maintenance,
install a strainer in the upstream line. If regulator pipe
line is expanding to a larger pipe line, always connect
sensing line to the larger pipe line.
12. For best performance, install in well drained horizontal
pipe, properly trapped, if a steam service application.
Recommended Piping Schematic For
Pressure Reducing Station
1. An inlet block valve should always be installed. An outlet
block valve is desirable.
2. A manual bypass valve is recommended for “hot piping”
systems to assist in piping warm-up at startup.
3. An isolation valve on the loading line is not recommended.
The threaded port in the diaphragm ring (25) for the
Model 8310HP 1+8 may be piped to a safe drainage
point, but no valve should be installed in the drain line.
4. Pipe unions are recommended for NPT screwed
installations to allow removal from piping.
5. An outlet pressure gauge should be located
approximately ten pipe diameters downstream, and
within sight. A loading pressure (or differential pressure)
gauge is recommended.
6. All installations should include a downstream relief
device if the inlet pressure could exceed the pressure
rating of any downstream equipment or the maximum
outlet pressure rating of the unit.
INSTALLATION, OPERATION & MAINTENANCE MANUAL
(Shaded portion for steam/condensate systems)
CAUTION
DO NOT HYDROSTATIC TEST THRU AN INSTALLED
UNIT; ISOLATE REGULATOR FROM TEST. DO NOT
HYDROSTATIC TEST THE LOADING PRESSURE
WITHOUT PRESSURE IN THE MAIN REGULATOR.
The upper range spring pressure level listed on the nameplate
is the recommended “upper operative limit” for the sensing
diaphragm (see Section IV. Start-up, Number 7.) Higher pres-
sures could cause internal damage. In addition, note on the
nameplate that the Inlet and Outlet pressure and temperature
ratings are at different levels.
TR
TR
ISO Registered Company

2 IOM-8310HP-DIFF
SECTION III
III. PRINCIPLE OF OPERATION
1. The Differential Model 8310HP is available in two
options: 8310HP-1+6 is single diaphragm construction;
8310HP-1+8 is double diaphragm construction. The
double diaphragm construction prevents the loading
fluid from direct mixing with the system fluid in case of
diaphragm failure.
2. Plug movement occurs as pressure variations register
on the diaphragm. One pressure is the outlet (p2)
or downstream pressure, which registers on the
“underneath” side of the diaphragm. The second
pressure registered is the loading (PLoad) pressure in
the spring chamber “above” the diaphragm. The range
spring determines the differential pressure level (PSet).
As outlet (P2) pressure drops, the range spring with
PLoad pressure pushes the diaphragm down, opening the
port; as outlet (P2) pressure increases, the diaphragm
is pushed up and the port closes. As the loading (PLoad)
pressure varies, the outlet (P2) pressure tends to follow.
An increase in PLoad (∆PLoad) will increase outlet P2
pressure by nearly an equal amount (∆PLoad = ∆P2); a
decrease in PLoad will have a similar effect on outlet P2
pressure.
3. For the 8310HP-1+6 (single diaphragm) design, a
complete diaphragm failure will cause the fluids to
mix in the spring chamber or loading pressure piping
system.
4. For the 8310HP-1+8 (double diaphragm) design, a
complete diaphragm failure will cause the regulator to
fail open, leaking fluid through the annular ring vent
hole. NOTE: Composition (soft) diaphragms may be
utilized only on -1+6 single diaphragm construction.
IV. START-UP
1. Start with the block valves closed. A bypass valve may
be used to maintain outlet pressure in the downstream
system without changing the following steps.
2. Remove the closing cap and relax the range spring
by turning the adjusting screw counter clockwise
(CCW) (viewed from above) a minimum of three (3)
full revolutions. This reduces the outlet (downstream)
pressure set point.
3. If it is a “hot” piping system, and equipped with a
bypass valve, slowly open the bypass valve to preheat
the system piping and to allow slow expansion of the
piping. Ensure proper steam trap operation, if installed.
Closely monitor outlet (downstream) pressure via gauge
to ensure not over-pressurizing. NOTE: If no bypass
valve is installed, extra caution should be used in starting
up a cold system; i.e. do everything slowly.
the regulator is flowing. If not, slowly rotate the regulator
adjusting screw clockwise (CW) (viewed from above)
until flow begins.
6. Continue to slowly open the inlet (upstream) block valve
until fully open.
7. Continue to slowly open the outlet (downstream) block
valve, especially when the downstream piping system
isn’t pressurized. If the outlet (downstream) pressure
exceeds the desired pressure, close the block valve
and go to Step 2, then return to Step 4.
8. When flow is established steady enough that the outlet
(downstream) block valve is fully open, begin to slowly
close the bypass valve, if installed. NOTE: The needle
valve (39) is shipped in a full open position. If the system
is unstable due to pressure fluctuations, slowly close
the needle valve (39) until the system becomes stable.
This needle valve should never be in a fully closed
position.
9. Set the regulator set point (Pset) by turning the adjusting
screw clockwise (CW) to increase outlet pressure or
CCW to reduce outlet pressure. The outlet (P2) pressure
under these conditions will approximate the desired
differential pressure when loaded with PLoad.
13. Model 8310HP 1+6 - refer to Figure 1; for 8310HP 1+8
refer to Figure 2. Regulator may be rotated around the
pipe axis 360°. Recommended position is with spring
chamber vertical upwards. Orient such that the spring
chamber vent hole does not collect rainwater or debris.
SECTION IV
Do not walk away and leave a bypassed regulator
unattended!
CAUTION
14. Regulators are not to be direct buried underground.
15. For insulated piping systems, recommendation is to not
insulate regulator.
4. Crack open the outlet (downstream) block valve.
5. Slowly open the inlet (upstream) block valve observing
the outlet (downstream) pressure gauge. Determine if

3IOM-8310HP-DIFF
SPRING UNDER COMPRESSION. Prior to removing flange
bolts, relieve spring compression by removing the adjust-
ing screw. Failure to do so may result in flying parts that
could cause personal injury.
WARNING
V. SHUTDOWN
2. Remove closing cap (35). Relax compression on
range spring (28) by turning adjusting screw (32)
CCW (viewed from above) until removed from
spring chamber (13).
3. Draw or embed a match mark between diaphragm
case (14), spring chamber casting (13) along
flanged area and across body spacer (25) for (1+8).
4. Remove all flange nuts (30) and bolts (29).
5. Remove spring chamber (13), spring button (27),
and range spring (28).
6. Draw second match mark on diaphragm case
(14) flange in alignment with a match mark on the
threaded end of the valve plug assembly (12) to
indicate “free vertical movement” position of the
valve plug assembly (12).
7. Secure the “flats” above the threaded end of the
valve plug assembly (12) with adjustable wrench,
remove pressure plate nut (24) by rotating CCW
(viewed from above).
NOTE: Do not rotate the valve plug assembly (12).
The plug (12.1) and seat rings (10 & 11) have been
mechanically lapped at the factory per ANSI Class
II seat leakage and assembled to provide optimum
“free vertical movement”.
8. Pryloosepressureplate(22)fromdiaphragm(s)(20).
Inspect pressure plate to ensure no deformation
due to over-pressurization. If deformed, replace.
Remove o-ring (53).
SYSTEM UNDER PRESSURE. Prior to performing any
maintenance, isolate the regulator from the system
and relieve all pressure. Failure to do so could result in
personal injury.
WARNING
10. Pressurize the source of loading (PLoad) pressure and
allow to fill the spring chamber cavity. Slightly open the
bleeder valve to vent any air as the spring chamber is
filling. Close bleeder valve when all air has escaped.
11. Develop system flow to a level near its expected normal
rate, and reset the regulator differential set point by
turning the adjusting screw CW (viewed from above)
to increase outlet pressure, or CCW to reduce outlet
pressure.
SECTION V
2. It is recommended that manual operation not be
attempted by a bypass valve during a shutdown.
3. When the loading pressure (PLoad) has been shutdown,
the regulator outlet pressure (P2) should decrease sub-
stantially. When this is observed, the inlet (upstream)
block valve may be closed. Close downstream block
valve.
SECTION VI
A. General:
1. Maintenance procedures hereinafter are based
upon removal of the regulator unit from the pipeline
where installed.
2. Owner should refer to owner’s procedures for
removal, handling, cleaning and disposal of
nonreusable parts, i.e. gaskets, etc.
3. If desired, new gaskets may be lubricated with a
light oil provided it is compatible with the fluid.
B. Diaphragm Replacement:
1. Using an overhead hoist, lift regulator out of the
piping installation and on to a flat work surface.
VI. MAINTENANCE
12. Reduce system flow to a minimum level and observe
set point. Outlet pressure will rise from the set point
of Step 9. The maximum rise in outlet pressure on
decreasing flow should not exceed the stated upper
limit of the range spring by greater than 10%; i.e. 10-
40 psig (.69-2.8 Barg) range spring, at low flow the
outlet pressure should not exceed 44 psig (3 Barg).
If it does, consult factory.
13. Retighten nut (33) on adjusting screw and install
closing cap.
Loading Pressure must be shut off before shutting
down the system pressure.
CAUTION
1. To prevent force imbalances and possible diaphragm
failure, the loading pressure (PLoad) should always be
shutdown first from its source of pressure. Systems
sequencing must ensure this occurs.

4 IOM-8310HP-DIFF
NOTES: a. Not removing the pusher plate (17) or
rotating the valve plug assembly (12) will provide
performance equal to original factory performance
when diaphragm(s) (20) is replaced with a like
diaphragm(s) (20). Refer to Section VI.C, steps
12 and 13 for correct diaphragm setting if pusher
plate (17) or stem lock nut (19) is removed, or valve
plug assembly (12) is rotated.
b. Instructions hereafter will refer to: The
-1+6 single diaphragm construction. (The -1+8
diaphragm construction is similar to the 1+6, with
the exception of a second set of diaphragms, a
body spacer (25) and a diaphragm spacer (26)).
Instructions for composition soft diaphragm
applies only to -1+6 option).
9. Remove diaphragm gasket (21) diaphragms (20
and pusher plate gasket (18). Clean gasket sealing
surfaces thoroughly.
10. Apply Federal Process Co. PLS-2 (or equivalent) to
both sides of pusher plate gasket (metal diaphragm
only). For composition diaphragm, apply a 1/8"
continuous bead of Dow/Corning RTV 732 (or
equivalent) around the center hole on the underside
of diaphragm.
11. Install new diaphragm gasket (21) on diaphragm
case (14) flange and new pusher plate gasket (18)
on pusher plate. NOTE: No gaskets utilized with
a composition (soft) diaphragm).
12. Position new diaphragms (20) over threaded end
of valve plug assembly (12). Align with bolt holes
on diaphragm case (14). Install o-ring (53).
13. Ensuring that the curved outer rim side of the
pressure plate (22) rests against the diaphragm
(20) directly, place the pressure plate over threaded
end of the valve plug assembly (12).
14. Apply Loctite 242 (or equivalent) to threads of
pressure plate nut (24) and Install pressure plate nut
on threaded end of valve plug assembly (12) and
tighten to a torque value of 75-80 Ft-lbs (101-108
Nm) for metal diaphragm, or 30-35 Ft-lbs (40-47 Nm)
for composition diaphragm. Maintain alignment of
match marks on the valve plug assembly (12) with
second match mark on diaphragm case (14) flange.
NOTE: Use two flange bolts (29) to keep multiple
diaphragms' (20) bolt holes properly aligned while
tightening pressure plate nut (24). DO NOT USE
FINGERS TO HOLD DIAPHRAGMS (20) DURING
TIGHTENING OF PRESSURE PLATE NUT.
15. Set range spring (28) on retainer hub of pressure
plate (22).
16. Place multi-purpose, high temperature grease into
depression of spring button (27) where adjusting
screw (32) bears. Set spring button (27) on to range
spring (28); ensure spring button (27) is laying flat.
Model Diaphragm
Material Torque Bolt Size
8310HP ALL 45 ft-lbs (61 Nm) 5/8" Ø
8310LP ALL 45 ft-lbs (61 Nm) 1/2" Ø
17. Aligning the match marks from B.3, place spring
chamber (13) over the above stacked parts.
Install all flange bolts (29) and flange nuts (30).
Mechanically tighten bolting (29) (30) in a cross
pattern that allows spring chamber (13) to be pulled
down evenly. Recommended torque values are
as follows:
NOTE: Never replace bolting (29) (30) with just any
bolting, if lost. Bolt heads and nuts are marked
with specification identification markings. Use only
proper grades as replacements.
18. Reinstall adjusting screw (32) with lock nut (33)
and closing cap.
19. To check for external leaks, spray liquid leak
detector to test around bolting (29)(30), diaphragm
case (14), and spring chamber (13) flanges
for leakage. Ensure that an outlet pressure is
maintained during this leak test of at least mid-
range spring level; i.e. 10-40 psig (.69-2.8 Barg)
range spring at 25 psig (1.7 Barg) test pressure
minimum.
C. Trim Inspection:
1. To inspect the internal trim parts, refer to Section
VI.A. and B.1 through 9 for diaphragm replacement
and proceed as follows.
2. Secure the “flats” on the threaded end of the valve
plug assembly (12) with wrench, rotate the pusher
plate (17) CCW to remove pusher plate and lower
pressure plate (23). Rotate stem lock nut CCW
to remove. NOTE: Do not rotate the valve plug
assembly (12).
3. Draw or embed a match mark between body (1)
and bottom flange (3).
4. Loosen and remove body stud nuts (8) CCW
(viewed from bottom) to remove bottom flange (3).
Inspect the bottom guide bushing (4) for excessive
wear. If worn, both the guide bushing (4) and the
bottom flange (3) must be replaced. NOTE: DO
NOT REMOVE BONNET (2). The bonnet (2) acts
as a guide to align the valve plug assembly (12)
into the seat rings (10 and 11).
5. Firmly grasp end of the valve plug assembly (12) by
hand and pull down and out of the body (1) cavity.
6. Inspect the seating surfaces of the plug (12) for
nicks or excessive wear.
7. Using a flashlight or other light source, examine the
interior of body (1) cavity. Also, inspect the seating

5IOM-8310HP-DIFF
Regulator Size Torque Bolt Size
1-1/2" - 2" (DN32-50) 50 Ft-lbs (68 Nm) 1/2"
3" - 4" (DN80-100) 100 Ft-lbs (136 Nm) 5/8"
surfaces of both the upper and lower seat rings
(10 and 11) for excessive wear. If either the plug
(12) seats or the seat rings (10 and 11) are worn
and in need of replacement, contact the factory
for authorization to return unit for repair. NOTE:
Overhaul and replacement of trim parts is not
easily accomplished by non-factory trained
personnel.
8. Remove the lower body gasket (6) and clean sealing
surface thoroughly.
9. Install valve plug assembly (12) up through and into
body (1). Place new body gasket (6) onto body.
10. Align match mark of C. 3 and replace bottom
flange (3) on body (1). Reinstall flange stud nuts
(8). Mechanically tighten nuts using an alternating
cross pattern that allows the bottom flange to be
pulled up evenly. Recommended torques values
are as follows:
11. Fully thread stem lock nut (19) and pusher plate (17)
on end of valve plug assembly (12). Refer to Figure
1 or 2 for correct orientation of the pusher plate (17).
12. Calibrate valve plug assembly (12) setting as
follows:
a) Lift and hold valve plug assembly (12) up tight
against the seats (10 and 11).
b) Adjust the pusher plate (17) so that the gasket
surface face of the pusher plate (17) is 1/2
rotation below the case flange surface.
NOTE: Option 1+8 - The gasket surface face of
the pusher plate (17) should be flush with the
top of the lower case flange surface.
c) Secure the “flats” milled on pusher plate and
rotate the stem lock nut (19) up tight against
the bottom of the pusher plate (17).
13. Grasp threaded end of valve plug assembly (12)
by hand and ensure that the assembly moves
freely by lifting the valve plug assembly (12) in and
out of the seats (10 and 11). If it does not move
freely, rotate valve plug assembly (12) CW until
new position is found which allows optimum “free
vertical movement” in and out of seats.
14. Proceed with diaphragm assembly instructions in
accordance with Section IV.B., steps 10 through
19. NOTE: Do not rotate valve plug assembly (12)
from optimum “free vertical movement” position
during final assembly.

6 IOM-8310HP-DIFF
SECTION VII
VII. TROUBLE SHOOTING GUIDE
A. Oversized regulator; inadequate rangeability. A1. Check actual flow conditions, re-size regulator for minimum and maximum
flow.
A2. Decrease regulator pressure drop; decrease inlet pressure by placing a
throttling orifice in inlet piping union; 2-stage pressure drop by using with
another regulator in series.
A3. Install next step higher range spring. Contact factory.
A4. Before replacing regulator, contact factory.
B. Worn plug/stem assembly; inadequate guiding. B1. Contact factory.
Remedies
Possible Causes
1. Erratic operation; chattering.
2. Leakage through the spring chamber vent hole.
A. Normal-life diaphragm failure. A. Replace diaphragm.
B. Abnormal short-life diaphragm failure. B1. Can be caused by excessive chattering. See No. 1. to remedy chatter.
B2. Can be caused by corrosive action. Consider alternate diaphragm material.
B3. For composition diaphragms, assure not subjecting to over-temperature
conditions.
B4. Downstream (outlet) pressure buildup occuring that overstresses
diaphragms. Relocate regulator or protect with safety relief valve.
RemediesPossible Causes
A. Plugged spring chamber vent. A. Clean vent opening.
B Fluid too viscous. B. Heat fluid. Contact factory.
RemediesPossible Causes
5. Sluggish operation.
A. Regulator not closing tightly. A. Inspect trim and plug alignment.
B. Downstream block. B. Check system; isolate (block) flow at regulator inlet - not outlet. Relocate
regulator if necessary.
C. No pressure relief protection. C. Install safety relief valve, or rupture disc.
D. Restricted diaphragm movement. D. Ensure no moisture in spring chamber at temperatures below freeze point.
Ensure no dust or debris entering vent opening. If rainwater or debris can
enter, re-orient spring chamber.
4. Excessive pressure downstream.
Possible Causes Remedies
A. Regulator undersized. A1. Confirm by opening bypass valve together with regulator.
A2. Check actual flow conditions, re-size regulator; if regulator has inadequate
capacity, replace with larger unit.
B. Incorrect range spring (screwing in CW of adjust- B. Replace range spring with proper higher range. Contact factory.
ing screw does not allow bringing pressure level
up to proper level).
C. Too much droop. C1. Review droop expected.
C2. Contact factory.
D. Restricted diaphragm movement. D. Ensure no moisture in spring chamber at temperatures below freeze point.
Ensure no dust or debris entering vent opening. If rainwater or debris can
enter, re-orient spring chamber.
RemediesPossible Causes
3. Downstream pressure will not reach desired setting.

7IOM-8310HP-DIFF
SECTION VIII
NEW REPLACEMENT UNIT:
Contact your local Cashco, Inc., Sales Represen-
tative with the Serial Number and Product code.
With this information they can provide a quotation
for a new unit including a complete description,
price and availability.
–7–
VIII. ORDERING INFORMATION
NEW REPLACEMENT UNIT vs PARTS "KIT" FOR FIELD REPAIR
To obtain a quotation or place an order, please retrieve the Serial Number and Product Code that was stamped
on the metal name plate and attached to the unit. This information can also be found on the Bill of Material
("BOM"), a parts list that was provided when unit was originally shipped. (Serial Number typically 6 digits).
Product Code typical format as follows: (last digit is alpha character that reflects revision level for the product).
PARTS "KIT" for FIELD REPAIR:
Contact your local Cashco, Inc., Sales Represen-
tative with the Serial Number and Product code.
Identify the parts and the quantity required to repair
the unit from the "BOM" sheet that was provided
when unit was originally shipped.
NOTE: Those part numbers that have a quantity indicated
under "Spare Parts" in column "A” reflect minimum
parts required for inspection and rebuild, - "Soft
Goods Kit". Those in column “B” include minimum
trim replacement parts needed plus those "Soft
Goods" parts from column "A".
If the "BOM" is not available, refer to the cross-
sectional drawings included in this manual for part
identification and selection.
A Local Sales Representative will provide quotation
for appropriate Kit Number, Price and Availability.
CAUTION
Do not attempt to alter the original construction of any
unit without assistance and approval from the factory. All
purposed changes will require a new name plate with ap-
propriate ratings and new product code to accommodate
the recommended part(s) changes.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be
construed as warranties or guarantees, express or implied, 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 product at any time without notice.
Cashco, Inc. does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any
Cashco, Inc. product remains solely with the purchaser.

8 IOM-8310HP-DIFF
Item No. Description Repair Kit A Item No. Description Repair Kit A
1 Body 20 Diaphragm(s) -------------------------------- ‡
2 Bonnet 21 Diaphragm Gasket ------------------------- ‡
3 Bottom Flange 22 Pressure Plate
4 Guide Bushing 23 Lower Pressure Plate
5 Stem Bushing 24 Pressure Plate Nut
6 Body Gasket---------------------------------- ‡25 Body Spacer (8310HP 1+8)
7 Body Stud 26 Diaphragm Spacer (8310HP 1+8)
8 Body Stud Nut 27 Spring Button
10 Upper Seat Ring 28 Range Spring
11 Lower Seat Ring 29 Flange Bolt
12 Valve Plug Assembly 30 Flange Nut
12.1 Plug 31 Nameplate
12.2 Stem 32 Adjusting Screw
12.3 Pin (Groove) 33 Adjusting Screw Lock Nut
13 Spring Chamber 34 Seal Washer
14 Diaphragm Case 35 Closing Cap
15 O-Ring ------------------------------------------ ‡36 Closing Cap Gasket ------------------------- ‡
16 Bonnet Nut 37 Bleeder Valve
17 Pusher Plate 38 Pipe Nipple
18 Pusher Plate Gasket ----------------------- ‡39 Needle Valve
19 Stem Lock Nut 53 O-ring
‡ Recommended Spare Part
MODEL 8310HP-1+6
Single Diaphragm Construction
Figure 1
View of Spring Chamber Topworks Only
See following page for body item numbers

9IOM-8310HP-DIFF
MODEL 8310HP-1+8
Double Diaphragm Construction
Figure 2

Cashco, Inc.
P.O. Box 6
Ellsworth, KS 67439-0006
PH [phone]
Fax. # [phone]
www.cashco.com
email: [email protected]
Printed in U.S.A. IOM-8310HP-Diff
Cashco do Brasil, Ltda.
Al.Venus, 340
Indaiatuba - Sao Paulo, Brazil
PH [phone]
Fax. No.
www.cashco.com
email: [email protected]
Cashco GmbH
Handwerkerstrasse 15
15366 Hoppegarten, Germany
PH [phone]
Fax. No. [phone]
www.cashco.com
email: [email protected]