Data Sheet

Large ET and ED Valves
D103554X012
Product Bulletin
51.1:ET/ED (Large)
March 2015
5
ET-C
The ET-C is designed to provide throttling or onoff
control of liquids and gases at cryogenic temperatures
as low as 198_C(325_F). These valves are identical to
the standard ET, but with a few differences, which
allow the valve to tolerate the very low temperatures.
These differences include:
 Style 3 Extension Bonnet
 BoltedIn Seat Ring
 Cryogenic Plug Seal
The style 3 ex tension bonnet is different from the
standard style 1 in that it is designed to locate the
temperature sensitive packing parts further away from
the valve body, preventing them from being exposed
to temperature extremes. The boltedin seat ring is
similar to that used with the ED valve and
accommodates the unavoidable material shrinkage
that occurs at cryogenic temperatures, which would
otherwise loosen the ET’s standard threadedin seat
ring. The cryogenic plug seal is used in place of the
standard ET plug seal ring. At cryogenic temperatures
below 73_C(100_F) the elastomer material the
standard seal ring is constructed from becomes brittle,
impacting the ability of the valve to shut off. The
maximum valve shutoff that can be attained at these
cryogenic temperatures with the cryogenic seal is
Class V.
See tables 3 and 5 for temperature limits.
ED Bore Seal
TheBoreSealisavailablefortheEDonlyandis
required for Class V shutoff applications where the
service temperature exceeds 316_C (600_F). For
service temperatures below 316_C(600_F) the ET
should be used when Class V shutoff is required. See
table 1 for availability and temperature limits and
figure 3.
TheBoreSealemploysametalCshaped seal ring that
is secured to the outside diameter of the valve plug.
When the valve plug comes into contact with the seat
ring, to close the valve, the Bore Seal is compressed
against the cage wall thereby blocking a secondary
leakage path that exists between the plug and cage
wall. When the valve plug is not in contact with the
seat ring (i.e. valve open) the Bore Seal is not engaged
and the piston rings that are also secured to the
outsidediameteroftheplugassumetheroleof
blocking this secondary leakage path.
Table 1. Bore Seal Availability and Temperature Limits (ED Only)
VALVE
(PRESSURE
CLASS)
VALVE SIZE, NPS
TRIM
DESIGNATION
(1)
VALVE BODY
MATERIAL
TEMPERATURE LIMIT
ANSI/FCI/IEC
SHUTOFF CLASS
_C _F
ED
(CL150 to CL600)
12, 14, 16, and 30
40 WCC/WC9 -29 to 371 -20 to 700
V
41
WCC -29 to 427 -20 to 800
WC9 -29 to 566 -20 to 1050
C12A -29 to 593 -20 to 1100
42 C12A -29 to 621 -20 to 1150
954
WCC -29 to 427 -20 to 800
WC9 -29 to 482 -20 to 900
1.Seetables3,5,and6formaterials.