DeZURIK
APCO CSD-800 Slanting Disc Check Valves
D12012
Page 8
July 2017
Maintenance
(Continued)
9. Screw diagonal flange bolts (7) in place but do not tighten.
10. Manually open and close disc (10) to check for binding and proper seating.
11. Tighten all diagonal flange bolts (7).
12. Place valve back in pipeline.
Operation
The valve as shipped from the factory may require minor adjustment, but is ready for operation. The
main body is 2 pieces to allow a greatly enlarged flow area through the disc and seat section. The disc
pivots off center with approximately 30% of the disc area above the pivot point to offer resistance
against the 70% disc area below the pivot point.
The shut off seating angle is 55°. The disc swings open through this 55° seat angle, traveling a short
distance, stopping at 15° off the horizontal.
CSD-800-BMB Valves
See Figure 1 for part identification.
Bottom Mounted Buffers are used when a free open and partial control of the disc during the closing
cycle is required. This unique arrangement allows the valve disc to close freely for the major portion of
its travel from full open to close. During the closing cycle, the disc comes in contact with the Buffer Rod
(33) which controls the speed of closing over the last 10% of the disc travel. This type of control
provides for adjustment to suit the best performance for the installation.
The oil operated Buffer Cylinder (39) incorporates the use of a two tank system of air over oil hydraulics
to operate the Buffer. The use of oil as the controlling media in this hydraulic system creates a
separate closed system which prevents contamination of the pipeline media.