cashco DA8 Instruction manual

INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM) IOM-DA8
01-17
I. DESCRIPTION AND SCOPE
The Model DA8 is a differential back pressure regulator used to control differential pressure between the upstream
(inlet or P1) pressure and a loading (PLoad) pressure to the spring chamber. Available in sizes 1/2" (DN15), 3/4"
(DN20), 1" (DN25), 1-1/4" (DN32), 1-1/2" (DN40), 2" (DN50), 2-1/2" (DN65), 3" (DN80) and 4" (DN100). With proper
trim utilization, the unit is suitable for liquid, gaseous, or steam service. Model DA8 is assembled in the “reverse”
flow direction arrangement that is balanced (to outlet).
MODEL DA8
(Formerly DA8/9)
DIRECT-ACTING, POSITIVE BIAS DIFFERENTIAL
BACK PRESSURE REGULATOR
SECTION I
II. REFERENCES
Refer to Technical Bulletin DA8-TB for technical
specifications.
ABBREVIATIONS
CCW – Counter Clockwise
CW – Clockwise
ITA – Inner Trim Assembly
III. INSTALLATION
4. An inlet pressure gauge should be located ap-
proximately ten pipe diameters upstream, and
within sight. A loading pressure (or differential
pressure) gauge is recommended.
5. Clean the piping of all foreign material including
chips, welding scale, oil, grease and dirt before in-
stalling the regulator. Strainers are recommended.
6. In placing thread sealant on pipe ends prior to
engagement, ensure that excess material is re-
moved and not allowed to enter the regulator upon
startup.
7. Flow Direction: Install so the flow direction matches
the arrow cast on the body or other markings such
as "in" and "out".
8. Precaution for Standard Diaphragm Construction:
The loading pressure should be lowered sufficiently
prior to shutting off the process fluid supply, to pre-
vent change to the diaphragm. Startup, shutdown,
and emergency operating procedures should be
reviewed to ensure that the loading pressure is
less than 50% of the Diaphragm Proof Rating (See
SECTION III
SECTION II
CAUTION
For welded installations, all internal trim parts, seals
and diaphragm(s) must be removed from regula-
tor 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.
1. Regulator may be rotated around pipe axis 360
degrees. For ease of maintenance, the recom-
mended position is with the spring chamber (4)
upwards. In liquid service it is recommended that
the spring chamber (4) be oriented downwards, and
that a customer supplied and installed vent valve
be provided at the external sensing connection to
bleed-off trapped gas/air under the diaphragm.
2. Provide space below, above, and around regulator
for removal of parts during maintenance.
3. Install block valves and pressure gauges to pro-
vide means for adjustment, operation, bypass, or
removal of the regulator. An isolation valve on the
loading line is not recommended.
ISO Registered Company

IOM-DA8
2
table below) before shutting off the process fluid
supply pressure. If the regulator is specified with
a fully supported diaphragm, then the diaphragm
will withstand a loading pressure equal to the
Diaphragm Proof Rating for the fully supported
diaphragm.
9. Upstream Sensing Installation Considerations –
Internal or External Sensing:
a. The regulator may be installed with internal or
external sensing. Unless otherwise specified,
the regulator is supplied by factory with internal
sensing. The regulator may be converted in
the field to external sensing (see Section VII
Maintenance, Paragraph H).
b. Reference DA8-TB, Table DAG-12 for recom-
mendations for applying external pressure
sensing.
c. For internal sensing, no external line is used.
For external sensing, use an external control
line. The line is connected from the port (1/4"
NPT) on the side of the body diaphragm flange
to an upstream pressure tap. The pressure
tap should be located a minimum of 10 pipe
diameters upstream of the regulator. It is
recommended that the upstream pressure
tap be located close to the point of use to
minimize the adverse affect of variable line
losses. A tubing outer diameter of 0.25 inch
is adequate for short sensing lines (less than
4 feet). Use 3/8" tubing or 1/4" Sch 40 pipe
for sensing lines of 5 to 50 feet.
d. For condensable vapors (i.e. steam) slope
the external sensing line downward 2 to 5
degrees to upstream piping to prevent water
pockets, which allows the diaphragm chamber
to always be self draining. The external sens-
ing line may be sloped upward for liquids or
gases. (i.e., non condensable fluids)
Recommended Piping Schematic for
Differential Back Pressure Station
CAUTION
The proof test pressure must not exceed the
diaphragm and body rating for the regulator.
A hydrostatic or pneumatic proof test is allowable un-
der the following conditions for the standard diaphragm
construction: Uniformly pressurize the valve body inlet,
valve body outlet, and loading chamber to the lesser of
the Diaphragm Proof Rating or 1.5 times the Inlet Pres-
sure Rating shown on the nameplate. For example, a
1" DA8 with Cast Iron Body and Spring Chamber, Neo-
prene Diaphragm (BC) has an Inlet Pressure Rating of
400 psig CWP. The lesser pressure of 1.5X 400 psig =
600 psig and the BC diaphragm proof rating of 750 psig
is 600 psig. Therefore, uniformly pressurizing the DA8
to 600 psig is allowable. Take care to uniformly depres-
surize at end of test.
TABLE 1 – DIAPHRAGM PROOF RATING IN PSIG (BARG)
Diaphragm Material
Body Sizes – inch (mm)
1/2" - 2" (DN15 - 50) 2-1/2" - 4" (DN65 - 100)
Standard Diaphragm
Construction
OPT-81 Full
Diaphragm Support
Standard Diaphragm
Construction
OPT-81 Full
Diaphragm Support
BC, EPR 750 (51.7) 1200 (82.7) 450 (31.0) 800 (55.2)
HK, NBR, HK+TFE 300 (20.7) 1200 (82.7) 225 (15.5) 600 (41.4)
FK 500 (34.5) 1200 (82.7) 225 (15.5) 600 (41.4)
Elastomeric TFE 125 (8.6) 125 (8.6) 125 (8.6) 125 (8.6)
17-7 PH SST 500 (34.5) 1500 (103) N/A N/A
Be-Cu 300 (20.7) 750 (51.7) N/A N/A
302 SST 350 (24.1) 800 (55.2) N/A N/A
Inconel 718 500 (34.5) 1500 (103) N/A N/A

IOM-DA8 3
IV. PRINCIPLE OF OPERATION
1. Valve plug movements modulate the flow across
the valve seat to maintain the inlet pressure (P1)
equal to the sum of the differential pressure (∆PDIFF)
and the loading pressure (PLoad). The inlet pressure
acting on the underside of the diaphragm tends to
lift the valve plug off the valve seat. The loading
pressure acting on the topside of the diaphragm
tends to close the valve plug against the valve
seat. The positive differential setting of the range
spring for the DA8 tends to close the valve plug
against the valve seat.
2. For a DA8 (single diaphragm) design, a complete
diaphragm failure will cause the inlet process fluid
to mix with the loading fluid.
SECTION V
V. STARTUP
1. Start with the block valves closed.
2. Relax the range spring by turning the adjusting
screw CCW (viewed from above) a minimum of
three (3) full revolutions. This reduces the ∆PDIFF
(differential) pressure set point.
3. If it is a “hot” piping system, and equipped with
a bypass valve, partially open the bypass valve
to preheat the system piping and to allow slow
expansion of the piping. Check for proper steam
trap operation if installed. Closely monitor inlet
(upstream) 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.
CAUTION
Do not walk away and leave a bypassed regulator
unattended!
5. Slowly open the inlet (upstream) block valve to
about 25% open, observing the inlet (upstream)
pressure gauge. Determine if the regulator is
flowing. If not, slowly rotate regulator adjusting
screw CCW (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 pip-
ing system is not pressurized. If the inlet (upstream)
pressure exceeds the desired pressure, close the
inlet block valve and go to Step 2. Close bypass
valve approximately 25%, and repeat procedure.
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. Under normal operating conditions, set the
DA8 regulator set point (∆PDIFF) by turn-
ing the adjusting screw clockwise (CW) to
increase inlet pressure or CCW to reduce
inlet pressure. The inlet (P1) pressure un-
der these conditions will approximate the
desired differential pressure for the DA8.
10. Pressurize the source of loading (PLoad) pressure
and allow to fill the spring chamber cavity. Slightly
open the bleeder valve (item 3) to vent any air as the
spring chamber is filling with a liquid loading fluid.
11. Develop system flow and pressure and readjust
setpoint as required to obtain desired response.
Performance should be checked at minimum and
maximum flow levels.
12. Install closing cap where applicable. The standard
regulator relies on a double o-ring rotary seal (item
34) around the non-rising adjusting screw.
SECTION IV

IOM-DA8
4
SECTION VI
VI. SHUTDOWN
CAUTION
Loading Pressure must be reduced before shutting
down the system pressure.
CAUTION
Do not walk away and leave a bypassed regulator
unattended.
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.
2. When the loading pressure (PLoad) has been
shutdown, the regulator inlet pressure (P1) should
decrease substantially.
3. On systems with a bypass valve, and where sys-
tem 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 out-
let (downstream) block valve.
4. If the regulator and system are both to be shut-
down, slowly close the inlet (upstream) block
valve. Close the outlet (downstream) valve only
if regulator removal is required.
VII. MAINTENANCE
A. General:
1. The regulator may be serviced without remov-
ing the regulator from pipeline. The regulator
is designed with quick-change trim to simplify
maintenance.
2. Record the nameplate information to
requisition spare parts for the regulator. The
information should include: Size, Product Code
and Serial Number.
3. Refer to Section VIII for recommended spare
parts. Only use original equipment parts sup-
plied by Cashco for rebuilding or repairing
regulators.
4. Owner should refer to owner's procedures for
removal, handling, cleaning and disposal of
nonreusable parts, i.e. gaskets, etc.
NOTE: On regulators originally supplied as
SpecialCleaningOption-55,-56,or-57,mainte-
nance must include a level of cleanliness equal
to Cashco cleaning standards of #S-1134,
#S-1542, and #S-1589 respectively. Contact
factory for details.
5. The Inner Trim is removed and replaced in the
body ( 23) as an assemblage of parts. The
Inner Trim Assembly, hereinafter called ITA,
consists of the following parts depending on
what dynamic sealing system the regulator is
using:
A detailed view of the Dynamic Side Seal parts is shown
in Figure 1 on the next page.
SECTION VII
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.*
* Includes external sensing connection if applicable.
Item Dynamic Side
No. Seal Type Part Description
7 ...................... All ........................Diaphragm Cap Screw
7 ...................... All ........................... Diaphragm Lock Nut
8 ...................... All .......Upper Diaphragm Pressure Plate
9 ...................... All ...................................... Diaphragm(s)
10 .....................All ..........Lower Diaphragm Pusher Plate
13 .................... All.........................Piston/Guide Bearing√
14 ..................... All ......................................... Stem Seals
14.1 ...............All ................................ Upper Stem Seal
14.2 ...............All ................................Middle Stem Seal
14.3 ...............All ..............................Lower Stem Seal√
14.4 ...............All ................ Lower Pusher Plate Gasket
20 ..................... All ...........................................Valve Plug
27 .....................All ........................... Dynamic Side Seal *
27.1 ...............CP..................................... TFE Cap Seal
27.2 ...............CP......................... O-ring Energizer/Seal
27.3 .............. UC .......... U-Cup Seal w/Metal Energizer
27.5 ...............PR................................. Piston Ring Seal
27.6 ...............PR........ Piston Ring Seal w/Metal Energizer
28 ..................... All ............................................ Seat Disc
29 .....................All ............................... Seat Disc Washer
30 .....................All ......................................Seat Disc Nut
* Possible option isType NO Dynamic Side Seal for standard
flow only..
√2-1/2" through 4" body sizes only and 1/2" - 1" with U-Cup.

IOM-DA8 5
Figure 1: Dynamic Side Seals
Type CP— TFE Cap Dynamic Seal
Type PR — PRA Dynamic Seal
Type UC — U-Cup Dynamic Seal Type NO — No Dynamic Seal
NOTE: Two separate
piston rings per assembly.
(Standard Flow Only)
(1-1/4"-2" Sizes)

IOM-DA8
6
1. Shut down the system in accordance with
Section VI.
2. Disconnect the external sensing line, if
installed.
3. The quick change trim allows for the disas-
sembly of the regulator while installed in the
pipeline. Alternatively the maintenance can
be done in a shop area. NOTE: It is easier to
repair the regulator when mounted upright in
a horizontal pipe run compared to a vertical
pipe run or a regulator mounted with spring
facing down. The description hereafter will
assume shop disassembly.
4. Place the valve unit in a vise with the spring
chamber (4) upwards.
5. Relax range spring (6) forces by turning ad-
justing screw (1) CCW (viewed from above)
until spring relaxes. The easiest way to check
this, is to carefully loosen the locknut (item
2). If the adjusting screw (item 1) sinks into
the chamber as the locknuts are loosened,
then the spring assembly is still in extension.
Turn the adjusting screw CW to remove the
extension. Fully remove the locknuts.
6. Loosen the diaphragm flange bolts (11) and
nuts (12) uniformly.
7. Place matchmarks on body (23) and spring
chamber (4) flanges. Completely remove bolt-
ing (11,12) Remove the spring chamber (4).
8. Remove spring follower (5) and spring (6.1).
9. Grasp opposite edges of diaphragm (9) and
withdraw the ITA from within the cage (19).
Set the ITA aside.
10. Evenly loosen the cage cap screws (18) in
single revolution increments until fully loos-
ened; remove cage cap screws (18).
11. Pull cage (19) up and out of body to remove
o-ring (15).
12. Remove lower cage gasket (21).
13. For metal diaphragm constructions, remove
diaphragm gasket (37) from body (23) dia-
phragm flange.
14. Remove body (23) from vise. Solvent clean
all removed metal parts.
C. Disassembly of the ITA:
1. Body Sizes 1/2" – 2". (See Figures 2 through
4):
a. Obtain two pieces of square-section
barstock with a 3/8"-7/16" dimension,
approximately 2 inches long.
b. Place plug (20) into a vise using the bars
of a. above positioned on "flats" located
on plug (20) to prevent vise jaw marks
from direct surface contact with the plug
(20). Orient with diaphragms on topside.
c. Sizes 1/2"-1": Remove diaphragm locknut
(7) by rotating CCW.
Sizes 1-1/4"-2": Remove diaphragm cap-
screw (7) by rotating CCW.
d. Remove upper diaphragm pressure plate
(8).
e. Remove diaphragm(s) (9, 9.1, 9.2, 9.9).
Examine diaphragm(s) to determine
whether failed; determine if operating
conditions are exceeding pressure drop
or temperature limits.
f. For composition diaphragm construction,
remove upper stem seal (14.1).
g. For metal diaphragm construction, remove
lower pusher plate gasket (14.4).
h. Remove lower diaphragm pusher plate
(10). For 1/2"-1" sizes, remove spacer
(13).
i. Remove middle stem seal (14.2).
j. Remove plug (20) from vise, rotate end-
for-end, and resecure in vise using same
metal bars above.
k. Loosen seat disc nut (30) CCW (viewed
from above) approximately two (2) revolu-
tions.
l. Remove assembly (20, 27, 28, 29, 30)
from vise. Complete removal of seat disc
nut (30), seat disc washer (29), and seat
disc (28).
2. Body Sizes 2-1/2" – 4". (See Figure 6):
a. Place seat disc nut (30) into a vise with
the plug (20) oriented vertically. Do NOT
over-tighten nut (30) in vise.
b. Place closed-end hex wrench onto dia-
phragm locknut (7). Place socket wrench
on 3/4" hex upper end of plug (20). Loosen
diaphragm locknut (7) while holding plug
(20) from rotating by socket wrench.
Remove diaphragm locknut (7) after fully
CAUTION
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.
B. Main Valve Disassembly:

IOM-DA8 7
loosened and socket wrench is removed.
c. Remove upper diaphragm pressure plate
(8).
d. Remove diaphragm(s) (9, 9.1, 9.2, 9.9).
Examine diaphragm(s) to determine
whether failed; determine if operating
conditions are exceeding pressure drop
or temperature limits.
e. Remove upper stem seal (14.1).
f. Remove lower diaphragm pusher plate
(10).
g. Remove middle stem seal (14.2).
h. Remove piston/guide bearing (13) with
dynamic side seal (27) in place.
i. Remove lower stem seal (14.3).
j. Place socket wrench on upper end of plug
(20) as in Step b. above. Rotate plug (20)
CCW (viewed from above) to loosen seat
disc nut (30). Once nut (30) is loosened,
remove partial assembly (20, 27, 28, 29,
30) from vise. Complete removal of seat
disc nut (30), seat disc washer (29) and
seat disc (28).
3. Examine the components (27.1, 27.2, 27.3,
27.4, 27.5, 27.6) of the dynamic side seal (27)
to determine if significant leakage was occur-
ring. If the dynamic side seal (27) shows signs
of significant leakage, determine if operating
conditions are exceeding pressure, pressure
drop, or temperature limits.
Remove dynamic side seal (27) components
from plug (20) for sizes 1/2" – 2", or from
piston/guide bearing (13) for sizes 2-1/2" –
4". Special care should be taken when using
“tools” to remove the components to ensure
that no scratches are imparted to any portion
of the plug (20) or piston/guide bearing (13)
groove.
4. Solvent clean all metal parts to be reused.
D. Inspection of Parts:
1. After inspection, remove from the work area
and discard the old “soft goods” parts (i.e.
o-rings, diaphragms, seals, etc.). Metal
diaphragms should be replaced. These parts
MUST be replaced with factory supplied new
parts.
2. Inspect the metal parts that will be reused. The
parts should be free of surface contaminants,
burrs, oxides, and scale. Rework and clean
the parts as necessary. Surface conditions
that affect the regulator performance are stated
below; replace parts that can not be reworked
or cleaned.
3. QC Finish & Dimensional Requirements:
a. Valve plug (20);
1. No major defects on plug's (20) bottom
guide spindle, or at guide area near
dynamic seal groove.
b. Cage (19);
1. 16 rms finish on cylinder bore. No
“ledges” formed due to wear from
moving dynamic side seal (27).
2. 16 rms finish on its seating surface
for tight shutoff.
c. Lower guide bushing (24);
1. 16 rms finish on bore.
2. Max 0.015 inch (0.38 mm) clearance
between valve plug (20) spindle and
lower guide bushing (24).
d. Internal sensing drilled plug (32);
1. Ensure that bore is minimum 0.125
inch (3.20 mm). Drill out as required.
e. Piston/Guide Bearing (13)(2-1/2"-4" only);
1. No defects at guide area near dynamic
seal groove.
4. Staging Material for Reassembly.
a. Inspect and clean parts, as necessary,
from the spare parts kit. (See Article
VII.A.4. comments concerning cleaning
for oxygen service.)
b. Lay out all the regulator parts and check
against the bill of material.
E. Reassembly of the ITA:
1. Position valve plug (20) with seat disc-end up-
wards. Place new seat disc (28) into recess of
lower end of valve plug (20) properly oriented.
2. Position seat disc washer (29) next to seat
disc (28).
3. Engage seat disc nut (30) to secure washer
(29) and seat disc (28) to valve plug (20).
Firmly hand-tighten.
4. Body Sizes 1/2" through 2":
a. Using the two square-section metal bar-
stock pieces of VII.C.1.a., clamp the plug
(20) into a vise with the plug's (20) spindle
pointed upwards.
b. Using a torque wrench, tighten the seat
disc nut (30) to 20-35 ft-lbs. by rotating
CW.
c. Remove assembly (20, 28, 29, 30) from
vise and rotate end-for-end and resecure
in vise using same metal bars.
5. Body Sizes 2-1/2" through 4":
a. Orient plug (20) with threaded end up-

IOM-DA8
8
wards, place into a vise, grasping the seat
disc nut (30); tighten the vise lightly, only
enough to "hold" the plug (20) from rotating
out of the vise. Caution: Over-tightening
the vise can distort the seat disc nut (30)
and give bad final torque values.
b. Place a torque wrench on the 3/4" hex
upper end of the plug (20); tighten the
seat disc nut (30) to 40-60 ft-lbs by rotat-
ing CW.
6. Installation of dynamic side seal (27) (See
Figure 1): NOTE: Dynamic side seal (27) for
sizes 2-1/2"-4" is located on the piston/guide
bearing (13). The dynamic side seal can be
installed on a work bench without need of a
vise.
a. Type CP:
1. Stretch o-ring energizer/seal (27.2)
over lower circumference of piston-
guide bearing (13) or valve plug
(20), taking care not to “cut” o-ring
energizer/seal (27.4). Using thumbs,
work the o-ring energizer/seal (27.4)
up and into the groove of the piston-
guide bearing (13) or valve plug
(20). NOTE: A very slight amount
of fluid and elastomer compatible o-
ring lubricant is recommended as an
installation aid.
2. For metal diaphragm construction,
insert camber adjusting washer (17.2)
into cage (19) and allow to rest in the
bottom of the cage (19).
3. Position TFE cap seal (27.1) ring with
rectangular cross-section at end of
piston-guide bearing (13) or valve
plug (20). Stretch cap seal (27.1) over
lower end of piston-guide bearing
(13) or valve plug (20) using thumbs
to work the cap seal (27.1) onto the
piston-guide bearing (13) or valve plug
(20). DONOT USEA TOOLFOR THIS
STEP. Continue pressing cap seal
(27.1) upwards towards the groove
until the cap seal (27.1) “snaps” into
the groove of the piston-guide bearing
(13) or valve plug (20).
4. Position piston-guide bearing (13) or
valve plug (20) over and into upper end
of cage (19) until the cap seal (27.1)
edge touches the upper lip of the cage
(19). While gently applying force to
press the piston-guide bushing (13)
or valve plug (20) into the cage (19),
simultaneously use fingers to lightly
press the cap seal (27.1) inwards into
the groove of the piston-guide bearing
(13) or valve plug (20) until the cap
seal (27.1) “slips into” the cage (19).
DO NOT USE TOOLS, LUBRICANT,
OR HEAVY FORCE TO ENGAGE
THE CAP SEAL (27.1) INTO THE
CAGE (19).
b. Type PR:
1. NOTE: A piston ring assembly (27.5)
consists of one metal corrugated
energizer and two piston ring seals.
Wrap corrugated metal piston ring
energizer into the groove of piston-
guide bearing (13) or valve plug (20).
2. Spread a piston ring seal and slide
over lower circumference of piston-
guide bearing (13) or valve plug (20).
Using thumbs and fingers, work the
piston ring seal into the groove of the
piston-guide bearing (13) or valve
plug (20). Repeat this procedure with
a second piston ring seal. Orient the
Z-cuts in the piston ring seals 180
degrees apart to minimize leakage
by the piston ring assembly.
3. Position piston-guide bearing (13) or
valve plug (20) over and into upper
end of cage (19) until the lower piston
ring seal touches the upper lip of the
cage (19). While gently applying force
to press the piston-guide bearing (13)
or valve plug (20) into the cage (19),
simultaneously use fingers to lightly
circumferentially press the piston
ring assembly (27.5) inwards into the
piston-guide bearing (13) or valve
plug (20) groove until the piston ring
assembly (27.5) “slips into” the cage
(19).
c. Type UC:
1. Stretch u-cup seal (27.3) over upper
circumference of valve plug (20), tak-
ing care not to “cut” u-cup seal (27.3)
on the protruding shelf that is part of
the valve plug's (20) groove. Ensure
that the u-cup seal (27.3) is oriented
with the center-open-upwards as
shown in Figure 1, as the u-cup seal
(27.3) depends upon the P1-Inlet
Pressure to pressure activate the seal
for proper sealing action.

IOM-DA8 9
d. Type NO:
1. For “standard” flow direction applica-
tions, it is not absolutely required that
a dynamic side seal (27) be installed.
(When included with the dynamic seal
(27), better guiding of valve plug (20)
results.) Type “NO” dynamic seal (27)
means NO dynamic seal.
2. The more common “Reverse” flow
direction always requires a dynamic
side seal (27).
7. Place fluid compatible thread anti-seize,
Locktite Corp., "Nickel Anti-Seize", or equal
on threaded portion of diaphragm cap screw
(7), sizes 1-1/4" and 1-1/2"; or, threaded post
portion of valve plug (20), sizes 1/2" – 1" and
2-1/2" – 4". ( NOTE: Valves cleaned for oxy-
gen service should use Fisher Scientific Co.,
"Fluorolube GR-362", or equal.)
8. Body sizes 1/2"-1", 2-1/2" through 4".
a. Place o-ring lower stem seal (14.3) over
upper-end of plug (20) and into groove in
plug (20).
b. Place properly oriented piston/guide bear-
ing (13) over upper-end of plug (20) and
into position on plug (20). Note: Part name
for item 13 on 1/2"-1" sizes is "spacer".
c. Place o-ring middle seal (14.2) over upper-
end of plug (20) and into groove of piston/
guide bearing (13).
9. Body sizes 1-1/4" through 2".
Place new o-ring middle stem seal (14.2) into
groove of valve plug (20) upper surface.
10. Position lower diaphragm pusher plate (10)
on/over upper end of valve plug (20) properly
oriented. For composition diaphragm construc-
tion the “tongue and groove” “ridge” should
be on upper side, “flat” side downwards. For
metal diaphragm construction the “rounded”
surface of the lower diaphragm pusher plate
(10) should be on upper side, “flat” side down-
wards.
11. For composition diaphragm construction, place
new o-ring upper stem seal (14.1) on/over
upper end of valve plug (20) and into groove
of lower diaphragm pusher plate (10).
12. For metal diaphragm construction, place
compatible gasket sealant on both sides and
place new lower pusher plate gasket (14.4)
on/over upper end of valve plug (20) and onto
lower diaphragm pusher plate (10). (Gasket
sealant is Federal Process Corp. “Gasoila” ,
or equal.)
13. Position new diaphragm(s) (9) on/over upper
end of valve plug (20). NOTE: For multiple
diaphragms (9) that include TFE material, the
TFE should be on the wetted side; for 6-ply
elastomeric TFE diaphragm (9), stackup is
TFE-TFE-HK-HK-TFE-TFE, beginning with
the lower wetted diaphragm (9) first.
14. Position upper diaphragm pressure plate (8)
on/over upper end of valve plug (20) prop-
erly oriented. For composition diaphragm
construction the "tongue and groove" "ridge"
should be on lower side, "flat" side upwards.
For metal diaphragm construction the "round-
ed" surface of the upper diaphragm pressure
plate (8) should be on lower side, "flat" side
upwards.
15. a. Body sizes 1/2" through 1": Engage
diaphragm locknut (7) to threaded
post portion of valve plug (20) and
torque to 60-70 ft-lbs. by rotating
CW.
b. Body Sizes 1-1/4" through 2": Insert
anti-seize coated diaphragm cap
screw (7) through stacked parts (8,
9, 10, 14.1, 14.4) and into upper end
of valve plug (20). Torque-tighten
diaphragm cap screw (7) to 120-130
ft-lbs.
c. Body Sizes 2-1/2" through 4": Engage
diaphragm lock nut (7) to threaded
post of valve plug (20) and wrench-
tighten firmly. While restraining valve
plug (20) from rotating by torque
wrench on upper end 3/4" hex, use
another wrench to tighten diaphragm
locknut (7) to a torque of 180 - 200
ft-lbs.
16. This completes assembly of ITA; remove from
vise.
F. Main Reassembly:
1. Place body (23) in a vise.
2. Fit the o-ring cage seal (15) into its body (23)
groove.
3. For metal diaphragm construction, place
sealant (“Gasoila” or equal) on both sides of
diaphragm gasket (37) and position on body
(23) diaphragm flange.
4. Position properly oriented lower cage gasket
(21) onto lower shelf of cage (19).

IOM-DA8
10
5. Insert cage (19) into body (23) recess. Properly
align all three cage bolt (18) holes as there is
only one circumferential location possible for
this alignment. Engage all of the cage bolts
(18), then evenly screw in the cage bolts in
one-half revolution increments, taking care
NOT TO “COCK” THE CAGE (19) IN THE
BODY. Torque the cage bolts (18) to 13-15
ft-lbs. For 1/2"-2" full support design, fit support
plate (35) into body counter bore.
6. Lubricate and install o-rings (34) into grooves
on the adjusting screw (1).
7. Assembly of range spring and spring chamber
for DA8:
a. Lubricate the threads of adjusting screw
(1) then thread into the spring follower (5).
The spring follower should be threaded
up adjusting the screw to within 3/8" of
the top threads (see sectional drawing,
figure 5.
b. Insert adjusting screw-spring follower into
spring chamber (4). NOTE: Milled slots in
spring follower must align with ribs in the
bore of the spring chamber. The top of
the adjusting screw must fit in the center
hole of spring chamber. A light rap with
a wooden handle of a hammer may be
needed to fully install the adjusting screw
into the spring chamber.
c. Aligning match marks and bolt holes,
place spring chamber (4) over range
spring (6.1). If the spring chamber
flange reaches the body flange without
a gap, turn adjusting screw (1) CW 2-3
turns. Repeat this procedure until the
flanges are approximately 1/8" apart.
Be sure that range spring is properly
seated into counterbore on spring follower.
8. Assembly of range spring assembly and spring
chamber for DA9:
a. Lubricate the threads of adjusting screw
(1), then thread into the range spring
assembly (6.2). The adjusting screw
should be threaded sufficiently into the
range spring assembly to allow easy fit-
ting of the spring chamber (see sectional
drawing, figure 6).
b. Thread the lower end of the range spring
assembly to the top of the valve plug. At
least three good threads of engagement
are required between the range spring
assembly and the valve plug. Back off
range spring assembly a fraction of the
turn to align the milled slots perpendicular
to the center line of the valve body. The
slots should now be ready to accept the
internal ribs of the spring chamber.
c. Aligning match marks and bolt holes
place spring chamber (4) over range
spring assembly (6.2). If the spring cham-
ber flange reaches the body flange with-
out the adjusting screw passing through
the center hole of the spring chamber,
then remove the chamber. Holding the
range spring assembly stationary, turn
the adjusting screw CW 2-3 turns or
as required so the top of the screw will
pass through center holes of the spring
chamber. After the top of the adjusting
screw passes through the center hole of
the spring chamber, continue to turn the
adjusting screw CW until the adjusting
screw is fully fitted into the spring cham-
ber. DO NOT allow the spring chamber
to rotate or the range spring assembly
may disengage from the valve plug.
d. Fit the locknut (2) to the top of the adjust-
ing screw. DO NOT over tighten the first
locknut. The adjusting screw should turn
freely in the spring chamber. Lock the
second locknut against the first locknut.
Again, check that the adjusting screw
turns freely.
9. Reinstall all flange bolts (11) and nuts (12)
with nameplate (99) located under one bolt
head. Hand-tighten nuts (12).
NOTE: If a six-ply diaphragm is being used,
it is important that the diaphragm (9) is “pre-
formed” – allow formation of a diaphragm (9)
convolution. Starting with the body bolts and
nuts (11,12) hand tightened, “preforming” can
be accomplished by any one of the following
techniques:
a. Relax range spring fully by rotating ad-
justing screw CCW.
b. Apply 30 psig (2.1 Barg) pressure to the
valve outlet.
OR
Block the valve outlet and apply 30 psig
(2.1 Barg) under the diaphragm through
the 1/4" NPT (plugged) external pres-
sure sensing connection on the valve
diaphragm flange.
c. Leave pressure on through tightening
of bolting (11,12).
10. Evenly tighten the body bolting (11,12) in an
alternating cross pattern in one revolution
increments to the following torque value:
Body Size
in (mm)
Torque
ft-lb (N-m)
1/2" - 2" (DN15-50) 30-35 (41-47)
2 1/2" - 4" (DN65-100) 45-50 (61-69)

IOM-DA8 11
If supplied, remove pressure of previous Step 14.
G. Units with Supported Diaphragm Designs:
1. With composition diaphragm construction,
a supported diaphragm (9) construction is
designated as Opt-81 High Inlet Pressure, and
comes with the highest range spring selection
for sizes 2" and smaller.
H. Converting Internal/External Sensing:
1. Disassemble the regulator and remove the
diaphragm(s) (9) according to Steps 1-12 in
Part B – Main Regulator Disassembly.
2. To convert from internal to external sensing,
remove the drilled pipe plug (32) and install a
solid pipe plug. Reverse this step for convert-
ing from external to internal sensing.
3. Reassemble the regulator according to Part
F – Main Regulator Reassembly.
I. Pressure Testing:
1. If a hydrostatic pressure test is performed,
pressure must be applied to all three of spring
chamber, inlet and outlet of body at the same
level.
2. Inboard Leakage Test (Seat + Dynamic Seal
Leakage).
a. Determine test pressure. If upper value
of range spring is less than 55 psig, use
test pressure of 5 psig less than upper
value of range spring. If upper value of
range spring is greater than 55 psig, use
test pressure of 50 psig.
b. While applying GN2or air pressurization
fluid, engage adjusting screw inwards
until valve appears to be closed. Add one
additional revolution inwards to adjusting
screw.
c. Tube outlet to a beaker of water to observe
number of escaping gas bubbles.
3. Pressure Containment Test.
(External Leak Test.)
a. See Section III, last paragraph and Table
1 for restrictions.
CAUTION
DO NOT HYDROSTATICALLY TEST WITHOUT SPRING
CHAMBER PRESSURIZED. NOT ADHERING WILL DO
PHYSICAL INTERNALS DAMAGE THAT COULD REN-
DER THE UNIT INOPERABLE.
b. Spray leak detection solution over the
bolting, diaphragm edge, body, spring
chamber and all other pressure boundary
areas, during external leak test.
4. Excessive leakage will require disassembly,
examination of sealing elements, correction
of problem, reassembly and retesting. NOTE:
This valve is NOT a bubble-tight shutoff de-
vice. See DA8-TB, Table DAG-10 for leakage
classes.

IOM-DA8
12
4. Diaphragm continually breaks (steam service regulators).
Possible Causes Remedies
A. Stem seals, which protect fluorocarbon elastomer in
diaphragm assembly, may have deteriorated. A. Replace with new stem seals.
B. Diaphragm nut may not be torqued to proper value. B. Confirm torque value in accordance with Section VII, paragraph
E-15.
C. Diaphragm too stiff causing it to crack in service.
C. Follow proper preforming and air pressure to underside of dia-
phragm techniques during diaphragm installation in accordance
with Section VII, paragraph F-9.
5. Diaphragm continually breaks (all regulators).
Possible Causes Remedies
A. Differential pressure across diaphragm may have
exceeded limits.
A. Reference limits as recorded in technical bulletin DA8-TB, as
well as where the various pressures are acting.
• Fluid (with fluid properties)
• Range of flow rate
• Range of inlet pressure
• Range of outlet pressure
• Range of fluid temperature
• Range of ambient temperature
Pressure readings should be taken at every location that pressure plays a role - i.e., regulator inlet (as close as
possible to inlet port), regulator outlet (as close as possible to outlet port), etc.
Following are some of the more common complaints along with possible causes and remedies.
SECTION VIII
Possible Causes Remedies
A. Sticking of internal parts. A. Remove internals, clean and if necessary, replace.
B. Load changes are too quick for system. B. Convert to external sensing (if necessary) and install an
orifice or needle valve in external sensing line.
C. Oversized regulator. C. Check actual flow conditions; resize regulator for minimum
and maximum flow; if necessary, replace with smaller regulator.
D. Unstable loading pressure. D1. Stabilize loading pressure; i.e. pump, control valve, etc.
D2. Air in loading piping. Vent spring chamber.
Possible Causes Remedies
A. Air trapped under diaphragm. A. Install valve on external sensing port and bleed off air.
(Install regulator upside down to help prevent reoccurrence.)
2. Erratic regulation, instability or hunting (liquid service).
1. Erratic regulation, instability or hunting.
Possible Causes Remedies
A. Debris in trim preventing movement. A. Clean unit of debris.
B. Undersized regulator. B. Check actual flow conditions; resize regulator for minimum and
maximum flow; if necessary, replace with larger regulator.
C. Mal-adjusted adjustment screw. C. Turn adjustment screw CCW.
3.Upstream pressure too high.

IOM-DA8 13
6. Leakage at diaphragm flange.
Possible Causes Remedies
A. Body bolts not torqued high enough. A. Torque to proper value (see Section VI, paragraph F-10).
7. Leakage across seat or dynamic side seal.
Possible Causes Remedies
A. Contamination (debris) in regulator. A. Remove internals, clean and if necessary, replace regulator.
B. Oversized regulator. B. Check actual flow conditions; resize regulator for minimum and
maximum flow; if necessary, replace with smaller regulator.
SECTION IX
IX. PARTS ORDERING INFORMATION
There are three methods to obtain parts ordering information/numbers. These methods are listed below, in order
of ease of entering. The least expensive method is to utilize parts in kits where possible.
METHOD A - USE OF PRODUCT CODE.
Step 1. If available, obtain the 18 character product code
number from:
a. The Bill of Materials (BOM) sheet attached
herein.
b. The metal tag attached to the regulator.
NOTE: Some regulators may not have the prod-
uct code located on the metal tag.
Step 2. Identify which kits or parts are desired from the
following:
a. The BOM, or refer to the cross-sectional draw-
ings.
b. Standard maintenance parts for a basic regula-
tor are identified on the BOM. Kit “A” contains
seal(s), diaphragm(s) and gasket(s). Kit “B”
contains trim replacement parts plus seal(s),
diaphragm(s) and gasket(s).
Step 3. Contact your local KM Sales Representative and
specify the product code number along with a
description of any parts not included in the kits.
Costs of required parts (and kits) can be given by
the Sales Representative.
METHOD B - NO PRODUCT CODE AVAILABLE
- DISASSEMBLED REGULATOR.
Step 1. Determine all available information from regula-
tor's metal tag.
a. Serial number (5-digit).
b. Regulator “Type” or “Model” number.
c. Size (may have to observe body tap).
d. Spring range.
e. Trim designation number (if available).
Step 2. Determine construction of trim and soft goods.
a. What is fluid?
b. What material is trim?
c. What material are the diaphragms?
d. What material is the seat?
e. What materials are used for static seals and
dynamic seals?
Step 3. With the information from Steps 1 and 2 above,
contact your local KM Sales Representative for
the proper identification numbers to use, and the
parts costs.
METHOD C - NO PRODUCT CODE AVAILABLE
- ASSEMBLED REGULATOR IN SERVICE.
Step 1. Determine all available information from metal
tag using Step 1, Method B.
Step 2. Contact your local KM Sales Rep with the above
information.
Step 3. Sales Representative will contact the factory to
determine the original internal construction. Fac-
tory will relay information to the Sales Represen-
tative.
Step 4. Await the Sales Representative’s return contact
with the proper part numbers and cost.
7 -
-

IOM-DA8
14
Figure 2
Composition Diaphragm
FTO – Reverse Flow Direction

IOM-DA8 15
Item No. Description
1 Adjusting Screw
2 Adjusting Screw Lock Nut
3 Bleeder Valve Assembly
4 Spring Chamber
5 Spring Follower (Button)
6 Range Spring
7 Diaphragm Cap Screw or Diaphragm Lock Nut
8 Upper Diaphragm Pressure Plate
9 ‡‡ Diaphragm
9.1 Diaphragm (Material #1)
9.2 Diaphragm (Material #2)
9.9 Diaphragm TFE Cover
10 Lower Diaphragm Pusher Plate
11 Flange Bolts
12 Flange Bolting Nuts
14 ‡‡ Stem Seal
14.1 Upper Stem Seal
14.2 Middle Stem Seal
15 ‡‡ Cage Seal
18 Cage Cap Screws
Item No. Description
19 Cage
20 Valve Plug
21 ‡‡ Lower Cage Gasket
23 Body
24 Lower Guide Bushing
26 Tap Plug (Not Shown)
27 ‡‡ Dynamic Side Seal
27.1 TFE Cap Seal
27.2 O-ring Energizer/Seal
27.3 U-cup with Metal Energizer
27.5 Piston Ring Seal
27.6
Piston Ring Seal w/Metal Energizer
28 ‡‡ Seat Disc
29 Seat Disc Washer
30 Seat Disc Nut
32 Internal Sensing Plug (External Sensing Only)
33 Internal Sensing Drilled Plug (Internal
Sensing Only)
34 ‡‡ Adjusting Screw O-Ring (Qty=2)
99 Nameplate (Not Shown)
‡‡ Recommended Repair Parts
Item Numbers and Descriptions below apply to Figures 2, 3 and 4.
Figure 3
Metal Diaphragm
FTO – Reverse Flow Direction

IOM-DA8
16
Item No. Description
7 Diaphragm Cap Screw
13 Piston/Guide Bearing
14 ‡‡ Stem Seals
14.1 Upper Stem Seal
14.2 Middle Stem Seal
14.3 Lower Stem Seal
15 ‡‡ Cage Seal
19 Cage
20 Valve Plug
21 ‡‡ Lower Cage Gasket
24 Lower Guide Bushing
28 ‡‡ Seat Disk
29 Seat Disk Washer
30 Seat Disk Nut
‡‡ Recommended Repair Parts
Figure 4: Body Sizes
2-1/2" – 4", Composition Diaphragm
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 con-
strued 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-DA8 17
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.

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. DA8-IOM
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.