DeZURIK
APCO CSD-800 Slanting Disc Check Valves
D12012
Page 12
July 2017
Operation
(Continued)
Table A: Maximum Stroke Adjustment of the Buffer Rod
Valve Size
6
8
10
12
14
16
18
20
Buffer Rod Stroke (in)
1/2
5/8
3/4
3/4
3/4
3/4
7/8
1
Valve Size
24
30
36
42
48
54
60
Buffer Rod Stroke (in)
1-1/4 1-1/4 1-1/2 1-7/8 2-1/4 2-3/8
2-5/8
5. Shut-off pump and observe rate of closing. Based on this initial run make necessary
adjustments to the Flow Control Valve (41B) and/or the Internal Cushion Needle Valve until
satisfactory closing is achieved.
An Adjustable Rod Stop (28) is mounted on the Buffer Rod to lock it in place when it is necessary to
disconnect the hydraulic cylinder for repairs while pump is running. In very rare cases however, it can
be used to shorten the Buffer Rod stroke when the system demands a higher percentage of free fall
closing of the Disc.
The Slanting Disc Check Valve with Bottom Mounted Buffer has two controlling stages in the closing
cycle. The Flow Control Valve (41B) controls the first stage of Disc closure and the secondary control
is the Internal Cushion Needle Valve which controls the remaining 20% of the Buffer stroke.
Start-up Procedure (CSD-800-TMD Valves)
See Figure 2 for part identification.
1. With the valve disc completely closed and both the hydro-pneumatic tank and oil reservoir in a
verti
cal position, check oil levels. Fill both tanks to the “street elbow” located on side with oil as
specified in “Oil Filling Procedure”. The Oil Reservoir (74) is provided with a breather cap, so
that at all times it remains at atmospheric pressure.
2. Using tire pump, pressurize the hydro-pneumatic tank (73) to a pressure as determined by the
formula below. This is the pressure at which the first pump start & stop tests will be made
through step 6, after which the pressure can be increased in increments of 2 psi, if the line
conditions require a faster response of closing of the disc on pump shutdown.
Tank pressure = K x P WHERE: P = Line pressure, PSI K= Valve Constant (See Table below)
Valve size
K
Valve size
K
6”
0.19
20”
0.21
8”
0.21
24”
0.21
10”
0.21
30”
0.30
12”
0.23
36”
0.30
14”
0.23
42”
0.24
16”
0.19
48”
0.30
18”
0.
19
54” *
*54” and larger Contact Factory.