BT RRE200 - Hydraulic Pump; Valve Block; Main Valve Block

Functions and parameters
Hydraulic system 6000
Publication No. Date Valid from serial number T-code
261828-040 2008-08-21 6051502 815, 816
© BT Repair Manual RRE140/160/180/200/250 4 – 59
4.10.4 Hydraulic pump
The pump is of gear wheel type (inner gear wheel) with fixed displace-
ment and is driven directly by the electric motor. The metallic contact
surfaces in the pump require very good lubrication, placing strict
requirements on the grade of hydraulic oil. They also require that the
motor rpm does not drop below a specified minimum value.
4.10.5 Valve block
Main valve block
The main valve block is located on the reach carriage. There are two
different versions of the main valve block: one for RRE and one for RRE
Ergo.
The valves for main lift, free lift, reach movement and cabin tilt are pres-
sure-compensated proportional valves. By means of pressure compen-
sation, the flow through the valve is kept constant for a given valve
deflection, irrespective of the load on the forks/cylinder.
The valve slides of the main valve block's proportional valves are indi-
vidually adjusted and cannot be replaced.
Pressure limitation
To protect the system against overpressure there is a pressure limiter
DV1 in the main valve block. The pressure limiter opens once the sys
-
tem pressure exceeds 25 MPa (250 bar).
Thanks to the main cylinders' and free lift cylinder's proportional areas,
no adjustment of the pressure limiter is needed to set the maximum
load. The valve block comes supplied with the pressure limiter DV1 set
at 25 MPa (250 bar).
For the reach movement and (where applicable) cabin tilt, there are
also pressure reducing valves DV2 and DV3, set at 15 MPa (150 bar).
RRE main valve RRE Ergo main valve