The System Circuit; The Basic Closed Circuit; Case Drain And Heat Exchanger - Danfoss Series 40 M46 Service Manual

Service Manual
Series 40 M46 Variable Pumps
Introduction
Cross section view
Needle bearing
Cylinder block
Manual displacement Control

The system circuit

8 | © Danfoss | September 2017
Gerotor
Valve plate
Swashplate

The basic closed circuit

Hydraulic lines connect the main ports of the pump to the main ports of the motor. Fluid flows in either
direction from the pump to the motor and back in this closed circuit. Either of the hydraulic lines can be
under high pressure. In pumping mode the angle of the pump swashplate determines which line is high
pressure as well as the direction of fluid flow.

Case drain and heat exchanger

The pump and motor require case drain lines to remove hot fluid from the system. The pump and motor
should be drained from their top most drain port to ensure the case remains full of fluid. Flow from the
motor case drain may route to the lower drain port on the pump housing and out the top most port, or
feed directly to the heat exchanger. The system requires a heat exchanger with a bypass valve to cool the
case drain fluid before it returns to the reservoir.
Ball bearing
Piston
Slipper
Sleeve Bearing
11026743 | AX00000027en-US0202
Shaft
Shaft Seal
Journal Bearing
Swashplate bearing pin
Servo piston