Case Drain And Heat Exchanger - Danfoss 90 Series Service Manual

Service Manual
Introduction
System circuit diagram
Control ha ndle
Reversible variabl e
Servo control cyli n der
displaceme nt pump
Input shaf t
Pump swa shplate
Servo control cyli n der
Working l o op (high pressure)
Series 90 Pumps
Basic closed circuit diagram
Reservoir
Input
MF
PV
Flow (Bi-directional)
Case drain line

Case drain and heat exchanger

The pump and motor require case drain lines to remove hot fluid from the system. The topmost port
drains the motor to ensure the case remains full of fluid. Fluid routes through the lower drain port on the
pump and out the topmost port to the reservoir. A heat exchanger, with a bypass valve, cools the case
drain fluid before it returns to the reservoir.
Displacem ent control valve
Heat excha nger bypass valv e
Orificed c heck
valve
Heat excha nger
Charge pressure relief valve
Multi-func tion valve
Servo
pressure
relief valves
Pump
Working loop (low pressure)
520L0818 • Rev 0101 • August 2015
Output
P104 120E
Reservoi r
Vacuum gauge
To
pump
case
Charge pum p
Multi-func tion valve
Loop flush ing valve
Suction line
Purge reli e f valve
Fixed displ a cement motor
Output sha ft
Motor sw ashplate
Motor
Control fluid
Case drain fluid
P102 000
9