Cashco DA8 Differential - Manual (Page 4)

IOM-DA8/9 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 reg u la tor
un at tend ed.
1. To prevent force imbalances and possible di-
a phragm failure, the loading pressure (P
Load
)
should always be shutdown fi rst from its source
of pressure. Sys tems sequencing must ensure
this occurs.
2. When the loading pressure (P
Load
) has been
shut down, the regulator inlet pressure (P
1
) should
de crease sub stan tial ly.
3. On systems with a bypass valve, and where sys-
tem pres sure is to be maintained as the regu la tor
is shut down, slowly open the bypass valve while
closing the inlet (upstream) block valve. Fully
close the inlet (up stream) block valve. (When on
bypass, the system pressure must be constantly
observed and manually reg u lat ed. Close the out-
let (down stream) block valve.
4. If the reg u la tor and system are both to be shut-
down, slowly close the inlet (upstream) block
valve. Close the outlet (down stream) valve only
if regu la tor re moval is required.
VII. MAINTENANCE
A. General:
1. The regulator may be serviced without
re mov 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
in for ma tion should include: Size, KM Product
Code and Serial Number.
3. Refer to Section VIII for recommended spare
parts. Only use original equipment parts sup-
plied by Cashco/KM for re build ing or re pair ing
regulators.
4. Owner should refer to owner's procedures for
removal, handling, cleaning and disposal of
nonreuseable parts, i.e. gaskets, etc.
NOTE: On regulators originally suplied as Spe-
cial Cleaning Option-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. Con tact
factory for details.
5. The Inner Trim is re moved and replaced in the
body ( 23) as an assemblage of parts. The
Inner Trim Assembly, here in af ter 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 per form ing
any maintenance, isolate the reg u la tor from the sys-
tem 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
fl ow only..
√ 2-1/2" thru 4" body sizes only and 1/2" - 1" with U-Cup.