Data Sheet
A31A Cryogenic Valve
Product Bulletin
21.1:Cryogenic-Rotary
October 2010
3
Table 1. Approximate Weights
VALVE
SIZE,
NPS
WAFER
CL150
SINGLE
FLANGE
CL150
WAFER
CL300
SINGLE
FLANGE
CL300
kg lbs kg lbs kg lbs kg lbs
3 12 27 16 36 12 27 16 35
4 21 46 22 48 21 46 24 52
6 24 53 28 61 24 53 28 61
8 34 75 40 89 47 104 52 115
10 57 125 67 148 80 176 100 220
12 74 164 93 206 103 227 135 298
14 87 191 120 265 142 314 249 548
16 133 294 182 401 213 470 325 716
18 170 374 231 510 259 570 434 956
20 210 463 302 665 401 884 582 1282
24 326 719 455 1004 512 1128 863 1903
Features
D Cryogenic Seal Improvement— The NOVEX
pressure-assisted metal seal design provides tight
shutoff (ANSI Class VI, ambient) and permits the
use of smaller, less expensive actuators in
applications requiring full ASME B16.34 shutoff
capabilities. The NOVEX seal is standard on all
A31A Cryogenic valves.
D Direct Actuation—The A31A Cryogenic NPS 3
through 8 Double D shaft allows direct mounting with
the 1035 actuator, eliminating the need for a coupler.
D Excellent Shutoff Integrity—Concentric
rotation enables the valve disc to remain in the
closed position in spite of line pressure surges or
actuator failure.
D Safety—Redundant shaft retention provides
added protection. The packing follower and shaft
step interact to hold the shaft securely in the valve
body. The NPS 3 through 12 valves use a one-piece
packing follower, and the NPS 14 through 24 valves
use a two-piece follower (see figure 5).
D Strength— The cast S31600 one-piece
extensions are welded directly onto the NPS 3
through 8 valves for greater strength under service
conditions.
D Easy Installation—The valve body self-centers
on the line flange bolts as a fast, accurate means of
centering the valve in the pipeline.
D Reliable Flange Gasketing Surface—Seal
retainer screws are located so there is no
interference with the sealing function of either flat
sheet or spiral wound line flange gaskets.
Installation
Recommended installation for the A31A Cryogenic
valve is with the shaft upstream of the seal (reverse
flow).
Dimensions for wafer-style and single-flange valves
are shown in figures 6, 7, 8, 9, 10, 11, 12, and 13
and tables 3, 4, 5, 6, 7, 8, 9 and 10.
For assistance in selecting the appropriate
combination of actuator action and open valve
position, consult your Emerson Process
Management sales office.