Cashco DA2 - Positive Differential - Manual (Page 4)

IOM-DA2 4
Item Dynamic
No. Seal Type Part Description
13 ..................... All ..........................Guide Bearing/Piston
14 ..................... All ............................... StaticStem Seal †
14.1 ............... All ................... Upper Static Stem Seal †
14.2 ............... All ...................Middle Static Stem Seal †
14.3 ............... All ................... Lower Static Stem Seal †
15 ..................... All ................................ Cage O-ring Seal
16 .................CW,PW .............................................. Wiper
17.1 ..............CW,PW ................................. Wiper Washer
17.2 ........... OR,CP,PR ........ Camber Adjusting Washer *
17.3 ................. UC ..................................... Seal Retainer
19 ..................... All ................................................... Cage
20 ..................... All ...........................................Valve Plug
21 ..................... All ............................................ Seat Ring
27 ..................... All ............................. Dynamic Side Seal
27.1 ........... CP,CW ................................. TFE Cap Seal
27.2 ...........CP, CW ............................. O-ring Energizer
27.3 .............. UC .......... U-Cup Seal w/Metal Energizer
27.4 .............. OR ....................................... O-Ring Seal
27.5............PR,PW.....Piston Ring Seal w/Metal Energizer
* Metal Diaphragm Only.
† Comp. Diaphragm Only.
SECTION VII
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 VI
VI. SHUTDOWN
1. To prevent force imbalances and possible di a-
phragm failure of the standard diaphragm con-
struction, the loading pressure (P
Load
) should be
lowered until the loading pressure (P
Load
) is less
than 50% of the diaphragm proof rating for the
standard construction. System se quenc ing
must ensure this oc curs.
2. It is recommended that manual operation not be
attempted by a bypass valve during a shutdown.
3. When the outlet pressure (P
2
) has been lowered
to 5 - 10 psig, the inlet (upstream) block valve
may be closed. The inlet pressure (P
1
) should
then decay to zero psig before the outlet (down-
stream) block valve is closed.
CAUTION D
Loading Pressure should be lowered as described
in Section III, paragraph 9 before shutting down the
system pressure.
WARNING 1
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.