| 4.1 in3/rev
|Flow@ 1800 rpm
|Maximum with atmospheric inlet
(6 in. Hg.)
Pressure (varies with model)
|With intermittent use up to
|Rated, continuous duty
||58.0 HP 43.0 kW
|| *Heavy-Duty, High-Pressure Models
- Separate Vatve Plate—Separate
hardened alloy steel valve plate resists wear. Unidirectional
designs include a precompression orifice from the discharge
port to the approaching cylinder. This method allows a uniform,
gradual pressure rise from inlet to outlet to minimize mechanical
shock and the resultant noise. A decompression orifice communicates
with the cylinder approaching the inlet port to the pump
case. This decompresses the oil that remains in the cylinder
after leaving the discharge port. This increases volumetric
efficiency and promotes stlffer systems by providing a means
to remove air-entrained oil from the circuit.
- Forged Rotor—One-piece
forged bronze rotor resists wear, pick-up, and fretting
caused by fluid-borne contaminants or low-lubricity fluid
conditions. Rotor is spllned to permit axial motion to compensate
for fluid film thickness and temperature changes.
- Ball-Shoe Pistons—The
ball of the piston knuckle joint is formed on the piston
shoe. This reduces the overall piston length and the resultant
side force on the cylinder bores.
- Roller Bearings—Dual,
heavy duty, tapered roller bearings support the drive end
of the input shaft. They are lubricated by the hydraulic
fluid and designed to accept external side loads normally
encountered in belt-drive applications.
- Reaction Plate Assembly—Heavy
forged steel reaction plate assembly has a separate hardened
alloy steel thrust plate, to distribute wear and reduce
- Dual Holddown System—Individual
piston springs preload the entire piston assembly against
the thrust plate. A fixed-clearance mechanical retainer
assembly holds the piston shoes against the thrust plate.
Compared to single-spring holddown systems, which retain
only the piston shoe, this method reduces mechanical lash,
wear of the piston knuckle, and related noise generation,
- Opposed Control Pistons—Displacement
changes are rapid and stable due to the high positioning
force available from the line pressure operated controls.
The opposed pistons hydrau-lically "clamp" the
displacement changing mechanism for optimal delivery stability.
- Lower System Costs—The
high-pressure capability of these units permit the use of
smaller size system components to handle the same horsepower
at lower cost. Heavy-duty shaft bearings accept overhung
loads, eliminating the need for a countershaft on most indirect
- Lower Operating Costs—High
overall efficiencies and power-saving controls reduce power
consumption and cooling requirements.
- Extended Service Life—Tough
alloy bronze mated to hardened alloy steels in the rotating
group, and heavy-duty bearings are used throughout the pump
to provide long life operation.
to permit easy field service. All parts subject to wear
are field serviceable.
- Low Noise Levels—Preloaded
pistons, unique port timing, and rigid case construction
yield low noise levels (PV320 83.5 dBa at 1800 RPM, 4000
psi, 24 GPM).