BRAND Hydraulics AO DIRECTIONAL CONTROL VALVES - Manual (Page 3)

04/14
T P
A B
Tandem Center (T) - Powers cylinder or motor in
both directions. Pump unloads to tank when
spool is in neutral. Cylinder or motor blocked
when spool in neutral. Open Center (O) - All of the ports are connected
to tank when the spool is in neutral. Allows
cylinder to move or motor to rotate when spool is
in neutral.
Fine Metering Spool (M) - Requires external
locking valves to hold cylinder when spool is in
neutral position. Extremely fine metering control.
This spool requires a pressure compensated
pump.
B A
P T
B A
P T
Tandem Metering Spool (TM) - Similar to (T)
spool except much finer metering control.
Cylinder or motor blocked in neutral and pump
unloads to tank.
P T
A B
Closed Center (C)- All ports are blocked in
neutral. Blocks cylinder or motor in neutral.
Required for use with pressure compensated
pump.
P T
A B
Tandem Three Way (T3) - Powers the cylinder in
one direction. Pump unloads to tank when spool
is in neutral, or when spool is being reversed.
Cylinder is blocked when spool is in neutral. Port
"B" is plugged.
P T
A B
SPOOL SCHEMATICS:
SAFETY PRECAUTIONS:
 It is the purchaser’s responsibility to determine the suitability of any Brand Hydraulics Co. product for an intended
application, and to ensure that it is installed in accordance with all federal, state, local, private safety and health
regulations, codes and standards. Due to the unlimited variety of machines, vehicles and equipment on which our
products can be used, it is impossible for Brand Hydraulics Co. to offer expert advice on the suitability of a product
for a specific application. It is our customer’s responsibility to undertake the appropriate precautions, testing and
evaluation to prevent injury to the end-user.
 Overpressure may cause sudden and unexpected failure of a component in the hydraulic system, resulting in serious
personal injury or death. Always use a gauge when adjusting a relief valve.