Cashco PBE User Manual

INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM)

12-13

MODEL PBE

PRESSURE BUILD /

ECONOMIZER REGULATOR

SECTION I

I. DESCRIPTION AND SCOPE

Model PBE is a pressure reducing regulator used to control pressure in gas storage tanks. Available in bronze
construction with brass and stainless steel trim, 1/4"(DN8) FNPT connections. Suitable for liquid and gaseous
service. Refer to Tech ni cal Bul le tin PBE-TB for specifi c design conditions and selection rec om men da tions.

SECTION II

II. INSTALLATION

CAUTION

IOM-PBE

Installation of adequate overpressure pro tec tion is recom­mended to pro tect the reg u la tor from overpressure and
all down stream equip ment from damage in the event of
regulator failure.

1. An inlet block valve should always be installed.

2. If service application is continuous such that
shut down is not readily accomplished, it is rec­ommended that an inlet block valve, outlet block
valve, and a manual bypass valve be installed.

3. Pipe unions should be installed to allow removal
from piping.

4. An outlet pressure gauge should be located ap­ proxi mately ten pipe diameters downstream, and
within sight.

5. All installations should include a downstream
safety re lief de vice if the inlet pressure could
exceed the pres sure rating of any downstream
equip ment or the maximum outlet pressure rating
of the unit.

6. Clean pip ing of all foreign material including chips,
welding scale, oil, grease and dirt before installing
the reg u la tor. Strainers are rec om mend ed.

with Economizer Relief Connection on backside

7. In plac ing thread seal ant on pipe ends pri or to
en gage ment, ensure that excess material is re­ moved and not allowed to enter regulator upon
startup.

8. Flow Direction: Install so the fl ow direction match-
es the arrow cast on the main regulator body.

9. For best performance, install in well drained hori­ zon tal pipe.

10. Recommended installation is with spring cham­ ber hanging directly be low the body in a ver ti cal
down wards orientation. Allows water to drain; etc.

11. Regulators are not to be buried un der ground.

12. For insulated piping systems, recommendation is
to not insulate regulator.

SECTION III

III. PRINCIPLE OF OPERATION

1. Movement occurs as pressure variations regis­ter on the diaphragm. The registering pressure
is the outlet, P2, or downstream pressure. The
range spring opposes di a phragm movement. As

SECTION IV

IV. STARTUP

CAUTION

The maximum outlet pressure is list ed on the name plate
as the upper range spring pres sure level, and is the rec om ­mend ed "upper operative limit" for the sens ing diaphragm
(See Section IV. Startup, Step 7). Higher press ures could
dam age the di a phragm. (Field hydro static tests fre quent ly
de stroy dia phragms. DO NOT HYDRO STATIC TEST THRU
AN IN STALLED UNIT; ISO LATE FROM TEST.)

1. Start with the block valves closed. A by pass valve
may be used to maintain out let pres sure in the
down stream sys tem without changing the fol low­ ing steps.

2. Relax the range spring by turning the adjusting
screw counter clockwise (CCW) a minimum of
three (3) full revolutions. This reduces the outlet
(down stream) pres sure 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
ex pan sion of the piping. Closely monitor outlet
(down stream) pres sure via gauge to ensure not
over-pressurizing. NOTE: If no bypass valve is

in stalled, extra caution should be used in starting
up a cold system; i.e. do everything slowly.

4. Crack open the outlet (downstream) block valve.

5. Slowly open the inlet (upstream) block valve ob­ serv ing the outlet (downstream) pressure gauge.

outlet pressure drops, the range spring pushes
the dia phragm down, opening the port; as outlet
pres sure in creas es, the diaphragm pushes up
and the port opening clos es.

2. A complete diaphragm failure will cause the reg u­ la tor to fail open.

De ter mine if the regulator is fl owing. If not, slowly
rotate the regulator adjusting screw clockwise
(CW) until fl ow 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 pip­ ing system isn't pressurized. If the outlet (down­ stream) pressure exceeds the desired pres sure,
close the block valve and go to Step 2, then return
to Step 4.

8. When fl ow is established steady enough that the
outlet (downstream) block valve is fully open,
be gin to slowly close the bypass valve if installed.

9. Develop system fl ow to a level near its expected
normal rate, and reset the regulator set point by
turning the adjusting screw CW to increase outlet
pressure, or CCW to reduce outlet pressure.

10. Reduce system fl ow to a minimum level and
ob serve set point. Outlet pressure will rise from
the set point of Step 9. The maximum rise in
outlet pressure on decreasing fl ow should not
exceed the stated up per limit of the range spring
by greater than 10%; i.e. 20-80 psig (1.38-5.52
Barg) range spring. (Example: at low fl ow the

outlet pressure should not exceed 88 psig (6.07
barg), if it does, con sult factory).

V. SHUTDOWN

1. On systems with a bypass valve, and where sys­ tem pressure is to be main tained as the reg u la tor
is shut down, slowly open the bypass valve while
closing the inlet (up stream) block valve. Fully
close the inlet (up stream) block valve. (When on
bypass, the sys tem pres sure must be con stant ly
observed and man u al ly reg u lat ed. Close the
outlet (down stream) block valve.

2

SECTION V

CAUTION

Do not walk away and leave a bypassed reg u la tor unat­tended.

2. If the regulator and system are to both be shut
down, slowly close the inlet (upstream) block
valve. Close the outlet (downstream) valve only
if reg u la tor re mov al is required.

IOM-PBE

SECTION VI

VI. MAINTENANCE

WARNING

SYSTEM UN DER PRES SURE. Prior to performing any
maintenance, isolate the reg u la tor from the system and
relieve all pres sure. Failure to do so could result in per­sonal injury.

A. General:

1. Maintenance procedures hereinafter are
based upon re mov al of the regulator unit from
the pipeline where in stalled.

2. Owner should refer to owner's procedures for
removal, handling, cleaning and disposal of
non reuseable parts, i.e. gaskets, etc.

3. Refer to Figure 1 for view of basic unit and
item number listing of parts.

B. Diaphragm Replacement:

1. Secure body cap (16) in a vise with the spring
chamber (2) oriented upwards.

CAUTION

To prevent damage to body cap, use soft jaws when se­curng the body in a vise.

WARNING

SPRING UNDER COMPRESSION. Prior to re mov ing the
spring chamber, relieve spring com pres sion by back ing
out the adjusting screw. Fail ure to so so may result in
fl ying parts that could cause personal injury.

2. Relax range spring (6) by turning adjusting
screw (3) CCW until removed from spring
cham ber (2).

3. Loosen spring chamber (2) by placing wrench
on “fl ats” and rotating CCW.

4. Remove spring chamber, spring button (5),
range spring (6) and diaphragm stop (9).

6. Using the "fl ats" on the plug (14) secure the
plug in a soft jawed vice. Rotate pressure
plate nut (7) CCW to loosen and remove
nut, lock washer (8), pressure plate (10),
diaphragm(s) (11) and gasket (13). (If a com­position di a phragm is used there is no gasket
(13)).

Diaphragm Sub as sem bly

7. Inspect pressure plate (10) to ensure no
de for ma tion due to over-pressurization. If
de formed, replace.

8. Remove diaphragm gasket (12).

9. Clean body (1) diaphragm fl ange surface. Do
not scratch diaphragm gasket seating sur face.

NOTE: Regulators origi nally sup plied as
“oxygen clean”, main tenance must in clude a
level of clean li ness equal to Cash co's clean ing
stan dard #S-1134. Con tact fac to ry for details.

10. Reassemble diaphragm subassembly by
plac ing gasket (13), diaphragm(s)(11), pres­sure plate (10) and lock washer (8) over the
threaded post. Assure the pressure plate is
placed with curved outer rim down next to the
diaphragm (11) surface. Place a thread seal­ant compound on the threads of the plug post
(14) prior to tightening the pusher plate nut (7)
to the fol low ing values:

Diaphragm

Metal 50 (5.6)

Composition 15 (1.7)

Torque

In-lbs (N-m)

11. Place dia phragm gas ket (12) into body (1)
re cess. Place di a phragm sub as sem bly on
top of gasket, nut side up.

IOM-PBE

5. Remove the diaphragm subassembly con­ sist ing of the pressure plate nut (7), lock
wash er (8), pres sure plate (10), diaphragm
(s) (11), gasket (13) and plug (14). NOTE

the quan tity of dia phragms (11) in cor po rated
in the assembly. De pend ing on outlet pres­ sure level, multiple metal diaph ragms may be
“stacked”.

12. Place diaphragm stop (9) and range
spring (6) over the pres sure plate nut
(7) of the di a phragm sub as sem bly.

13. Apply Christolube or equivalent into de pres­ sion of spring button (5) where ad just ing
screw (3) makes contact. Set spring but ton on
top of range spring (6); en sure spring button
is laying fl at on top of spring.

3

14. Rotate the spring chamber (2) CW by hand
into the threaded portion of the body (1)
ensuring not to cross thread. Continue ro tat­ ing CW until fi rmly seated against the upper
di a phragm gasket (12). Tighten to 30-35 ft-lbs
(41-47 N-m) torque.

15. Apply Christolube or equivalent to threads of
adjusting screw (3) and install ad just ing screw
with locknut (4) into the spring chamber (2).

C. Trim Replacement:

1. Trim inspection requires that the diaphragm
subassembly be removed. Refer to Sec tion
VI.B. Steps 1-9.

10. Apply Formula 8 thread sealant to the body
cap (16) male threads. Carefully position the
body cap over the piston spring and engage
the threads. NOTE: While engaging the

threads - may encounter minimum resistance
from upward force of the piston spring. With

hand pressure continue to press body cap
down evenly until threads are fully engaged.
Tighten to 30-35 ft.lbs. (41-47 N-m). These

two parts seal metal-to-metal with no gasket.

11. Re-orient body assembly in vise and secure
by the body cap, (body cap oriented down).

12. Place economizer seat ring in the recess in
the body. Concave seat surface face up.

2. Inspect seating surface of plug (14) and seat­ing surface of seat ring (15). If either seating
surface shows signs of erosion/wear, the plug
(14) and seat ring (15) should be replaced.

3. To remove piston assembly, secure body
(1) in a vise with the body cap (16) oriented
upwards.

CAUTION

To prevent damage to the body, use soft jaws when secur­ing body in a vise. Position body so that vise does not
close over the inlet and the outlet connections.

4. Rotate body cap (16) CCW to remove from
body.

5. Remove piston spring (18), piston assembly
(17) and u-cup seal (22). Inspect TFE seat­ing surface on the piston assembly (17).

NOTE: The pis ton (17) assembly can not be
dis-assembled. If the TFE seat is damaged,
re place the entire piston assembly.

13. Reinstall diaphragm subassembly, spring,
etc. per Sec tion VI.B. Steps 10-15.

6. Clean body (1) cavity and all parts to be re­used. NOTE: Regulator originally sup plied as

“oxygen clean”, main te nance must include a
lev el of clean li ness equal to Cashco's clean­ ing stan dard #S-1134. Contact factory for
de tails.

7. To re-install trim, slide new u-cup seal (22)
(open end of cup facing down) into recess in
body.

8. Slide the piston assembly into the body, TFE
seat end in fi rst. NOTE: Piston should move

freely up and down within the body cavity.

9. Center the piston spring (18) on top of the
piston.

4

IOM-PBE

SECTION VII

VII. TROUBLE SHOOTING GUIDE

1. Erratic operation; chattering.

Possible Causes Remedies

A. Oversized regulator; inadequate rangeability. A1.

B. Worn piston; inadequate guiding. B. Replace trim ( possible body replacement).

C. Weakened/broken piston spring. C. Replace piston spring. De ter mine if corrosion is causing the failure.

2. Regulator can't pass suffi cient fl ow.

Possible Causes Remedies

A. Regulator undersized. A1.

B. Incorrect range spring (screwing in CW of ad-

justing screw does not allow bringing pressure
level up to proper level).

C. Too much droop. C1.

3. Leakage through the spring chamber vent hole.

Check actual fl ow conditions, re-size regulator for minimum and maximum fl ow.

A2.

Increase fl ow rate.

A3.

Decrease regulator pressure drop; decrease inlet pressure by placing a throttling orifi ce
in inlet piping union.

A4.

Install next step higher range spring. Contact factory.

A5.

Before replacing regulator, contact factory.

Confi rm by opening bypass valve together with regulator.

A2.

Check actual fl ow conditions, re-size regulator; if regulator has inadequate capacity,
replace with larger unit.

Replace range spring with proper higher range. Contact factory.

B.

Review droop expected.

C2.

Contact factory.

Possible Causes Remedies

Normal-life diaphragm failure.

A.

Abnormal short-life diaphragm failure.

B.

Replace diaphragm.

A.

Can be caused by excessive chattering. See No. 1. to remedy chatter.

B1.

Can be caused by corrosive action. Consider alternate diaphragm material.

B2.

For composition diaphragms, ensure not subjecting to over-temperature conditions.

B3.

Downstream (outlet) pressure buildup occurring that overstresses diaphragms. Relo-

B4.

cate regulator or protect with safety relief valve.

4. Excessive pressure downstream.

Possible Causes Remedies

A. Regulator not closing tightly. A. Inspect the seating. Clean composition seats,- are depressed, nicked or embedded

B. Downstream block. B. Check system; isolate (block) fl ow at regulator inlet - not outlet. Relocate regulator

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

with debris, replace trim.

if necessary.

dust or debris entering vent opening. If rainwater or debris can enter, reorient regulator.

IOM-PBE

5

SECTION VIII

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 refl ects revision level for the product).

–

NEW REPLACEMENT UNIT:

Contact your local Cashco, Inc., Sales Rep re sen ta­ tive 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.

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 ap­propriate ratings and new product code to accommodate
the recommended part(s) changes.

–

7

PARTS "KIT" for FIELD REPAIR:

Contact your local Cashco, Inc., Sales Rep re sen ta tive
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 un-

der "Spare Parts" in column "A” refl ect 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 identifi cation
and selection.

A Local Sales Representative will provide quotation for
appropriate Kit Number, Price and Availability.

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 specifi cations 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.

6

IOM-PBE

Figure 1

Repair Parts
Item No. Description Kit B
1 Body
2 Spring Chamber
3 Adjusting Screw
4 Locknut
5 Spring Button
6 Range Spring
7 Pressure Plate Nut
8 Lock Washer
9 Diaphragm Stop
10 Pressure Plate
11 Diaphragms ---------- ‡‡

IOM-PBE

Repair Parts
Item No. Description Kit B
12 Diaphragm Gasket --‡‡
13 Economizer Plug Gasket -- ‡‡
14 Economizer Plug -----‡‡
15 Economizer Seat Ring - ‡‡
16 Body Cap

17 Piston ------------------- ‡‡
18 Piston Spring ----------‡‡

22 U-cup Seal ------------- ‡‡

7

Cashco, Inc.
P.O. Box 6
Ellsworth, KS 67439-0006
PH [phone]
Fax. # [phone]
www.cashco.com
email: [e-mail]

Printed in U.S.A. IOM-PBE

Cashco GmbH
Handwerkerstrasse 15
15366 Hoppegarten, Germany
PH [phone]
Fax. No. [phone]
www.cashco.com
Email: [e-mail]

Cashco do Brasil, Ltda.
Al.Venus, 340
Indaiatuba - Sao Paulo, Brazil
PH [phone]
Fax. No.
www.cashco.com
Email: [e-mail]