Valve Options; General; Testing Of Multiple Unit Valves - Eaton Vickers CM2 Series Overhaul Manual

Section VII – Valve Options
A. General
Operating sections can be supplied with anti-cavitation
check valves, and combination anti-cavitation check valves
with cylinder port relief valves. The use of these accessories
will be identified by a special feature suffix on the model
number. Refer to the installation drawings listed in Table 1
for these options.
1. Anti-Cavitation Check Valve - To eliminate cavita-
tion created in the system, an anti-cavitation check valve
may be employed. The valve can be installed on each cylin-
der port of any operating section where required. When the
system pressure is less than tank pressure, a vacuum is
created. The anti-cavitation check valve equalizes the unbal-
anced pressure condition by metering fluid from the tank
Section VIII – Testing
Vickers Mobile Division application engineering personnel
should be consulted for recommendations on test stand cir-
cuit requirements and construction. If test equipment is avail-
able, valves should be tested at the recommended flow and
pressure shown on installation drawings M-259218 and
M-259219.
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passage back to the pressure port. The anti-cavitation check
valve is located in valve operating sections next to the cylin-
der ports and function when the spool is in neutral and oper-
ating position.
2. Anti-Cavitation Check with Cylinder Port Relief
Valve - The anti-cavitation check with cylinder port relief
valve is a combination of anti-cavitation check valve with an
integral cylinder port relief valve sub-assembly. The operation
of the anti-cavitation check feature is described in paragraph
VII, A, 1. The cylinder port relief sub-assembly limits the
maximum pressure in the cylinder port. The relief sub-assem-
bly normally functions when the valve spool is in the neutral
position. Fluid is discharged from the cylinder port to the tank
passage of the directional valve. The pressure setting is
generally higher than the main system relief valve. The relief
valve subassemblies are pre-set at the factory.