HYDROSTATIC PUMP AND MOTOR
The Variable Displacement Pump can be operated with
fixed or variable input speeds and provides an infinitely
variable output flow between 0 and maximum flow in
either direction. A variety of controls are available for the
Variable Displacement Pumps and Motors which are
described on the following pages.
The Fixed Displacement Motor can be operated in either
direction of rotation with infinitely variable output speeds
between its 0 and maximum speed.
Manual Displacement Control
The Standard Displacement Control provides a pump
output flow (displacement), in either direction, that is
approximately proportional to the angular movement of
the control handle. The control will return to neutral if the
control handle is released. The internal centering
mechanism is not sufficient to overcome external
This control has an orifice for controlling maximum
orifice is available in various sizes for matching the
control to the system.
Torque on the Control handle shaft
190 - 210 PSI
13 - 15 BAR
must not exceed 150 in. lbs.
Specifications and Requirements
160 - 180 PSI
11 - 12.5 BAR
Sundstrand Heavy Duty Hydrostatic transmissions have
certain pressures that must be maintained as well as
some requirements and limitations which must be
40 PSIG Max.
3 BAR Max.
10 In. Hg. Max.
254 mm Hg Max.
10 Micron Nominal
*Above case pressure. Some units may have special
charge pressure settings.
**Measured at charge pump inlet. (May be exceeded
during cold weather start up).
*6,000 PSI (414 BAR) maximum working pressure with