cashco 1465 Instruction manual

II. INSTALLATION
INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM) IOM-1465
12-16
Recommended Piping Schematic
for Pressure Reducing Station
MODEL 1465
PRESSURE REDUCING REGULATOR
SECTION I
I. DESCRIPTION AND SCOPE
The Model 1465 is a high pressure reducing regulator designed primarily for analytical sampling and low flow
applications. Size is 1/4" (DN8). With proper trim utilization, the unit is suitable for liquid and gaseous service. Refer to
Technical Bulletin 1465-TB for design conditions and selection recommendations. NOT FOR DEAD END SERVICE.
SECTION II
1. An inlet block valve should always be installed.
2. If service application is continuous such that
shutdown 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
approximately ten pipe diameters downstream,
and within sight.
5. 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.
6. Clean the piping of all foreign material including
chips, welding scale, oil, grease and dirt
before installing the regulator. Strainers are
recommended.
7. In placing thread sealant on pipe ends prior to
engagement, ensure that excess material is
removed and not allowed to enter the regulator
upon startup.
8. Flow Direction: Install in accordance with the
flow direction arrow cast on the body. The inlet
pressure is connected to the bottom connection
and the outlet (reduced) pressure is connected
to the side connection. When installing, hold by
the body (1) hex to keep the regulator firm.
Outlet
@ P2
Bypass
Model 1465
Reducing
Regulator
SRV
Supply
@ P1
For welded installations, all internal trim parts,
seals and diaphragm(s) must be removed from
regulator body prior to welding into pipeline. The
heat of fusion welding will damage non-metallic
parts if not removed. NOTE: This does not apply to
units equipped with extended pipe nipples.
CAUTION
CAUTION
Installation of adequate overpressure protection
is recommended to protect the regulator and all
downstream equipment from damage in the event
of regulator failure.
Do not dead end (no flow demand) downstream of
the regulator. The inlet pressure will transmit past
the metal seat (not positive shut-off) and equalize on
the downstream. This will lead to diaphragm failure,
regulator malfunction, and possible damage to system
instrumentation downstream.
CAUTION
ISO Registered Company

2IOM-1465
SECTION III
rotate the regulator adjusting screw (12) clockwise
(CW) 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.
9. Develop system flow to a level near its expected
normal rate, and reset the regulator setpoint by
turning the adjusting screw (12) CW to increase
outlet pressure or CCW to reduce outlet pressure.
10. Reduce system flow to a minimum level - observe
setpoint. Outlet pressure will rise from the setpoint
of Step 9. The maximum rise in outlet pressure
on decreasing flow should not exceed the stated
upper limit of the range spring (10) by greater than
10%; i.e. 5-30 psig (.34-2.1 Barg) range spring, at
low flow the outlet pressure should not exceed 33
psig (2.3 Barg). If it does, consult factory.
III. PRINCIPLE OF OPERATION
1. Movement occurs when the inlet pressure passes
by the seat causing a distributive force on the
underside of the diaphragm. This, in turn, opposes
the point force of the range spring causing
upward movement of the diaphragm, allowing
the plug to seat. When set pressure decreases,
due to demand, the distributive force beneath the
diaphragm lessens - allowing the range spring to
open the seat and regulate pressure.
2. A complete diaphragm failure will cause the
regulator to fail open.
SECTION IV
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. Relax the range spring (10) by turning the adjusting
screw (12) counter clockwise (CCW) a minimum
of three (3) full revolutions. This reduces the outlet
(downstream) pressure setpoint. NOTE: If the
Option -2 or -22 is utilized, the adjusting screw
(12) and locknut (13) are replaced with a knob
(18) and locknut (13). With Option -2 +80 or -22
+80, the adjusting screw (12) and locknut (13) are
replaced with a handwheel subassembly (20) and
locknut (13).
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.
4. Crack open the outlet (downstream) block valve.
5. Slowly open inlet (upstream) block valve observing
the outlet (downstream) pressure gauge.
Determine if the regulator is flowing. If not, slowly
9. Basic Regulator - (Refer to Figure 1): Regulator
may be installed in any position in relation to
the pipe. Recommended position is with spring
chamber vertical upwards. Orient such that the
spring chamber vent hole does not collect rainwater
or debris.
10. Regulators are not to be direct buried underground.
11. For insulated piping systems, recommendation is
to not insulate the regulator.
DO NOT HYDROSTATIC TEST THROUGH AN
INSTALLED UNIT; ISOLATE REGULATOR FROM
TEST. The upper range spring pressure level listed on
the nameplate is the recommended "upper operative
limit" for the sensing diaphragm (see Section IV.
Startup, Number 7). Higher pressures could cause
internal damage. In addition, note on the nameplate
that the Inlet and Outlet pressure and temperature
ratings are at different levels.
CAUTION

IOM-1465
3
2. Relax range spring (10) by turning adjusting
screw (12) CCW until removed from spring
chamber (2). NOTE: If the Option -2 or -22 is
utilized, the adjusting screw (12) and locknut
(13) are replaced with a knob (18) and locknut
(13). With the Option -2 +80 or -22 + 80, the
adjusting screw (12) and locknut (13) are
replaced with a handwheel subassembly (20)
and locknut (13).
3. Loosen spring chamber (2) by placing wrench
on “flats” and rotating CCW. DO NOT use the
flats on either side of the vent hole.
SECTION VI
A. General:
1. Maintenance procedures hereinafter are
based upon removal of the regulator from
the pipeline where installed.
2. Owner should refer to owner’s procedures for
removal, handling, cleaning and disposal of
non-reusable parts, i.e. O-rings, etc.
3. Refer to Figure 1 for the standard regulator
and its options.
B. Diaphragm Replacement:
1. Securely install the body (1) in a vise with the
spring chamber (2) directed upwards.
4. Remove spring chamber (2), spring button
(11), and range spring (10). NOTE: For
units with Option -80 (spring ranges 270-400
psig (18.6-27.6 Barg) and 360-500 psig (24.8
-34.5 Barg)) also remove the thrust bearing
(15), upper bearing washer (16), and lower
bearing washer (17). Inspect threads of spring
chamber (2) for cleanliness.
5. Remove pressure plate (9) and inspect
to ensure no deformation due to over-
pressurization. If deformed, replace.
6. Remove diaphragm(s) (8), O-ring (7) and
pusher plate (6). Inspect pusher plate (6)
to ensure no deformation due to over-
pressurization. If deformed, replace. Discard
O-ring (7) and diaphragm(s) (8).
7. Clean body (1) and body recess according
to owner's procedures. NOTE: On regulators
originally supplied as “oxygen clean”, Option
1465-55, maintenance must include a level
of cleanliness equal to Cashco’s cleaning
Standard #S-1134. Contact factory for details.
8. Install new O-ring (7) and diaphragm(s) (8).
NOTE: Refer to the quantity of diaphragm(s)
(8) incorporated in the bill of materials listing.
Depending on outlet pressure level, multiple
metal diaphragms may be “stacked”.
9. Visually center pressure plate (9) on
diaphragm(s) (8). Place the range spring (10)
on to the retainer hub of the pressure plate
(9).
10. Place multi-purpose, high temperature grease
into the depression of the spring button (11)
where adjusting screw (12) bears. Set spring
button (11) onto range spring (10); ensure
spring button (11) is laying flat. NOTE: For
units with Option -80 (spring ranges 270-400
psig (18.6-27.6 Barg) and 360-500 psig (24.8-
34.5 Barg) position spring button (11), thrust
V. SHUTDOWN
1. On systems with a bypass valve, and where system
pressure is to be maintained as the regulator is
shut down, slowly open the bypass valve while
closing the inlet (upstream) block valve. Fully
close the inlet (upstream) block valve. (When on
bypass, the system pressure must be constantly
observed and manually regulated. ) Close the
outlet (downstream) block valve.
SECTION V
2. If the regulator and system are to both be
shutdown, slowly close the inlet (upstream) block
valve. Close the outlet (downstream) valve only
if regulator removal is required.
CAUTION
Donotleaveabypassedregulatorunattended.
VI.MAINTENANCE
WARNING
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
SPRING UNDER COMPRESSION. Prior to removing
spring chamber, relieve spring compression by
backing out the adjusting screw or handwheel. Failure
to do so may result in flying parts that could cause
personal injury.

4IOM-1465
bearing (15), upper bearing washer (16), and
lower bearing washer (17) on top of the range
spring (10).
11. Apply an appropriate lubricant to the threads
of the spring chamber (2). Reverse Steps
B.2 and B.3 to complete assembly. Tighten
spring chamber (2) to body (1) with a 30-35
Ft-lbs torque value.
12. Pressurize with air and spray with liquid leak
detector to test around body (1) and spring
chamber (2) for leakage. Ensure that an outlet
pressure is maintained during this leak test of
at least mid-range spring level; i.e. 125-200
psig (8.6-13.8 Barg) range spring, 163 psig
(11.2 Barg) test pressure minimum.
C. Trim Inspection:
1. Trim inspection requires that the diaphragm(s)
be removed. Refer to previous procedure
Section VI.B, steps 1 through 7.
2. Remove body (1) from vise and secure a
screwdriver, tool end up, in vise. Set body (1)
so as to engage screwdriver into slotted end of
the plug (3) from the body (1) inlet connection
and hold firm.
3. Remove pusher plate (6). Looking down into
the body (1) cavity, use a slotted tool to push
down on the spring seat (5) and slip sideways
to disengage (through slot) from plug (3).
4. Remove spring seat (5) and plug spring (4).
5. Grasp plug (3) while carefully lifting body (1).
Remove plug (3) from body (1) inlet, taking
care not to allow plug (3) to drop out.
6. Inspect integral seat in body (1). If seat shows
erosion or wear, replace regulator.
1. Erratic operation; chattering.
7. Clean debris from within body (1) cavity.
Clean parts to be reused according to
owner's procedures. NOTE: On regulators
originally supplied as "oxygen clean", Option
1465-55 maintenance must include a level of
cleanliness equal to Cashco's cleaning spec.
#S-1134. Contact factory for details.
8. Inspect spring seat (5), plug spring (4) and
plug (3). If worn, nicked or depressed, replace
regulator.
9. Lap plug (3) with lapping compound by
inserting it back up into the body (1) inlet
and hold firm. Engage a screwdriver into the
slotted end of the plug (3) from the body (1)
inlet and rotate plug (1) back and forth in a
circular motion. Do not overlap. Clean lapping
compound on plug (3) and in body (1).
10. Reverse steps 1 through 5 for reassembly.
NOTE: When reassembling plug (3), plug
spring (4), and spring seat (5), be sure that
this "assembly" is centered into the body (1)
cavity to ensure proper seating of plug (3).
Apply an appropriate lubricant to the threads
of the spring chamber (2). Tighten spring
chamber (2) to body (1) with a 30-35 Ft-lbs
torque value.
11. Bench test unit for suitable operation. NOTE:
Regulators are not tight shut off devices.
Even if pressure builds up beyond setpoint,
a regulator may or may not develop bubble
tight shut off.
12. Pressurize with air and spray with liquid leak
detector to test around body (1) and spring
chamber (2) for leakage. Ensure that an outlet
pressure is maintained during this leak test of
at least mid-range spring level; i.e. 125-200
psig (8.6-13.8 Barg) range spring, 163 psig
(11.2 Barg) test pressure minimum.
SECTION VII
VII. TROUBLE SHOOTING GUIDE
Possible Causes Remedies
A. Oversized regulator; inadequate
rangeability.
A1. Check actual flow conditions, re-size regulator for minimum and
maximum flow.
A2. Increase flow rate.
A3. Decrease regulator pressure drop; decrease inlet pressure by
placing a throttling orifice in inlet piping union.
A4. Install next step higher range spring. Contact factory.
A5. Before replacing regulator, contact factory.
B. Cavitation B. Use multiple 1465's in series to stage the pressure drops. Refer
to 1465 Technical Bulletin for water cavitation chart.

IOM-1465
5
5. Sluggish operation.
2. Leakage through the spring chamber vent hole.
3. Regulator can't pass sufficient flow.
4. Excessive pressure downstream.
6. Excessive seat leakage.
7. Leakage out of threaded connection between body and spring chamber.
Possible Causes Remedies
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, ensure not subjecting to over-
temperature conditions.
B4. Downstream (outlet) pressure buildup occurring that overstresses
diaphragms. Relocate regulator or protect with safety relief valve.
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. Plugged trim. B. Remove regulator from line and check for debris in inlet
connection.
C. Incorrect range spring(screwing in
CW of adjusting screw
does not allow bringing pressure
level up to proper level).
C. Replace range spring with proper higher range. Contact factory.
D. Too much droop D1. Review droop expected.
D2. Contact factory.
E. Cavitation E. Use multiple 1465's in series to stage the pressure drops. Refer
to 1465 Technical Bulletin for water cavitation chart.
Possible Causes Remedies
A. Regulator not closing tightly.
A. Inspect the seating. Check the plug (3), plug spring (4), and spring
seat (5) are centered in body (1) cavity. Replace regulator should
these steps not remedy.
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 enter, re-orient regulator.
Possible Causes Remedies
A. Fluid too viscous. A. Heat fluid. Contact factory
Possible Causes Remedies
A. Foreign matter on seating surface,
erosion of seating surface. A. Inspect and clean seat. If seat eroded, replace regulator.
B. Cavitation B. Use multiple 1465's in series to stage pressure drops. Refer to
1465 Technical Bulletin for water cavitation chart.
Possible Causes Remedies
A. Insufficient spring chamber torque. A. Tighten spring chamber on body using sufficient torque.
B. Damaged o-ring B. Replace o-ring.

6IOM-1465
SECTION VIII
NEW REPLACEMENT UNIT:
Contact your local Cashco, Inc., Sales
Representative 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
Representative 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 appropriate 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.

IOM-1465
7
Item Number Description
1 Body Subassembly
2 Spring Chamber
3 Plug
4 Spring
5 Spring Seat
6 Pusher Plate
7 O-ring
8 Diaphragm
9 Pressure Plate
10 Range Spring
11 Spring Button
12 Adjusting Screw
13 Adjusting Screw Lock Nut
14 Name Plate
15 Thrust Bearing
16 Upper Bearing Washer
17 Lower Bearing Washer
18 Knob
19 Mounting Nut
ITEM NUMBERS NOT SHOWN
20 Handwheel Subassembly
21 Pin
Figure 1: Basic Model 1465
Option -80, High Pressure
Spring Chamber Construction
Option -22 Panel Mounting (hand-
wheel portion is same for Option -2
Handwheel)
2
12
19
13
18
2
16
15
17
13
14
10
8
5
4
3
1
6
7
9
2
11
22
12

8IOM-1465
ATEX 94/9/EC: Explosive Atmospheres and Cashco Inc. Regulators
These valves satisfy the safety conditions according to EN 13463-1 and EN 13463-5 for equipment group IIG 2 c.
Caution: Because the actual maximum temperature depends not on the equipment itself, but upon the fluid temperature, a
single temperature class or temperature cannot be marked by the manufacturer.
Specific Precaution to Installer: Electrical grounding of valve must occur to minimize risk of effective electrical discharges.
Specific Precaution to Installer: Atmosphere vent holes should be plugged to further minimize the risk of explosion.
Specific Precaution to Maintenance: The Valve Body/ Housing must be regularly cleaned to prevent buildup of dust deposits.
Specific Precaution to Maintenance: Conduct periodic Continuity Check between Valve Body/ Housing and Tank to minimize
risk of electrical discharges.
Attention: When repairing or altering explosion-protected equipment, national regulations must be adhered to. For maintenance
and repairs involving parts, use only manufacturer's original parts.
ATEX requires that all components and equipment be evaluated. Cashco pressure regulators are considered components.
Based on the ATEX Directive, Cashco considers the location where the pressure regulators are installed to be classified
Equipment-group II, Category 3 because flammable gases would only be present for a short period of time in the event of a leak.
It is possible that the location could be classified Equipment-group II, Category 2 if a leak is likely to occur. Please note that the
system owner, not Cashco, is responsible for determining the classification of a particular installation.
Product Assessment
Cashco performed a conformity assessment and risk analysis of its pressure regulator and control valve models and their
common options, with respect to the Essential Health and Safety Requirements in Annex II of the ATEX directive. The details
of the assessment in terms of the individual Essential Health and Safety Requirements, are listed in Table 1. Table 2 lists all of
the models and options that were evaluated and along with their evaluation.
Models and options not listed in Table 2 should be assumed to not have been evaluated and therefore should not be selected
for use in a potentially explosive environment until they have been evaluated.
Standard default options for each listed model were evaluated even if they were not explicitly listed as a separate option in the
table. Not all options listed in the tables are available to all models listed in the tables. Individual TB’s must be referenced for
actual options.
When specifying a regulator that is to be used in a potentially explosive environment one must review the evaluations in Table 1
and 2 for the specific model and each and every option that is being specified, in order to determine the complete assessment
for the unit.
A summary of the models and options found to have an impact on ATEX assessment due to potential ignition sources or other
concerns from the ATEX Essential Health and Safety Requirements, are listed below.
1. The plastic knob used as standard on some models, (P1, P2, P3, P4, P5, P7, 3381, 4381, 1171, and 2171) is a
potential ignition source due to static electricity. To demonstrate otherwise, the knob must be tested to determine
if a transferred charge is below the acceptable values in IEC 60079-0 Section 26.14 (See items 25, 27, and 28 in
Appendix A). Until the plastic knob has been shown to be acceptable, then either the metal knob option, or a preset
outlet pressure option is required to eliminate this ignition source (See items 45 and 64 in Tables).
2. The pressure gauges offered as options on a few of the regulator models (DA’s, P1-7, D, 764, 521), use a plastic
polycarbonate window that is a potential ignition source due to static electricity. To demonstrate that the gauges are
not a potential source of ignition, the gauges would need to be tested to determine if a transferred charge is below
NOTICE
Only for Product Codes wherein hazard
category ATEX has been selected.

IOM-1465
9
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-1465
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]
indicating the gauge is compliant with the ATEX Directive (See items 26, 27, and 28 in Appendix A). Until compliance
is determined, regulators should not be ordered with pressure gauges for use in potentially explosive environments.
3. Tied diaphragm regulators with outlet ranges greater than 100 psig should be preset to minimize the risk that improper
operation might lead to an outboard leak and a potentially explosive atmosphere (See item 6 in Table 1).
4. Regulators must be ordered with the non-relieving option (instead of the self-relieving option) if the process gas they are
to be used with is hazardous (flammable, toxic, etc.). The self-relieving option vents process gas through the regulator
cap directly into the atmosphere while the non-relieving option does not. Using regulator with the self- relieving option
in a flammable gas system could create an explosive atmosphere in the vicinity of the regulator.
5. Regulators with customer supplied parts are to be assumed to not have been evaluated with regard to ATEX and thus
are not to be used in a potentially explosive environment unless a documented evaluation for the specific customer
supplied parts in question has been made. Refer to Table 1 for all models and options that have been evaluated.
Product Usage
A summary of ATEX related usage issues that were found in the assessment are listed below.
1. Pressure regulators and control valves must be grounded (earthed) to prevent static charge build-up due to the flowing
media. The regulator can be grounded through any mounting holes on the body with metal to metal contact or the
system piping can be grounded and electrical continuity verified through the body metal seal connections. Grounding
of the regulator should follow the same requirements for the piping system. Also see item 30 in Table 1.
2. The system designer and users must take precautions to prevent rapid system pressurization which may raise surface
temperatures of system components and tubing due to adiabatic compression of the system gas.
3. Heating systems installed by the user could possibly increase the surface temperature and must be evaluated by the
user for compliance with the ATEX Directive. User installation of heating systems applied to the regulator body or
system piping that affects the surface temperature of the pressure regulator is outside the scope of this declaration and
is the responsibility of the user.
4. The Joule-Thomson effect may cause process gases to rise in temperature as they expand going through a regulator.
This could raise the external surface temperature of the regulator body and downstream piping creating a potential
source of ignition. Whether the Joule-Thomson effect leads to heating or cooling of the process gas depends on
the process gas and the inlet and outlet pressures. The system designer is responsible for determining whether the
process gas temperature may rise under any operating conditions. If a process gas temperature rise is possible under
operating conditions, then the system designer must investigate whether the regulator body and downstream piping
may increase in temperature enough to create a potential source of ignition.
The process gas expansion is typically modeled as a constant enthalpy throttling process for determining the temperature change.
A Mollier diagram (Pressure – Enthalpy diagram with constant temperature, density, & entropy contours) or a Temperature –
Entropy diagram with constant enthalpy lines, for the process gas, can be used to determine the temperature change. Helium
and hydrogen are two gases that typically increase in temperature when expanding across a regulator. Other gases may
increase in temperature at sufficiently high pressures.
Product Declaration
If the above issues are addressed by selecting options that do not have potential sources of ignition, avoiding options that
have not been assessed, and by taking the proper usage issue precautions, then Cashco regulators can be considered to be a
mechanical device that does not have its own source of ignition and thus falls outside the scope of the ATEX directive.