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Hägglunds DUc Drive unit
| Scope of delivery
Bosch Rexroth AB, Version 06.2020, RE 15326-WA
5.4
Hydraulic fluids
The Hägglunds hydraulic system is primarily designed for operation with hydraulic
fluids according to ISO 11158 HM.
Fluids by the standards given in
are suggested. Before the start of project
planning, see
Hydraulic fluid quick reference
, for detailed
information on hydraulic fluids and specific additional demands
Table 4:
Suggested fluid types
ISO 11158
ISO 15380
ISO 12922
Mineral oil based and
mineral oil related hydraulic
fluids
Environmentally acceptable
hydraulic fluids
Fire resistant hydraulic fluids
Details regarding the selection of hydraulic fluid
The hydraulic fluid should be selected such that the operating viscosity in the
temperature range, as measured in the motor housing, is within optimum operation
range, see
General recommendation is to have a system temperature of
50°C, see dotted line in
. A VG 68 fluid will render just above 40 cSt at this
point.
• Optimum viscosity range is 40 to 150 cSt.
• Running above 150 cSt or below 40 cSt results in reduced efficiency.
• Running above 400 cSt results in substantial efficiency loss.
• For pumps, the maximum start-up viscosity is 2000 cSt.
• For motors, starting at above 10000 cSt imparts unnecessary strain on parts.
• Running below 30 cSt may impact the service life.
•
Running below 20 cSt may render instant seizure.
Fig. 8:
Selection diagram for viscosity ranges with straight fluids, i.e. viscosity index 100
14
20
30
40
50
60
80
100
150
200
300
400
600
1000
2000
3000
5000
10000
20000
0
32
-40
-40
-30
-22
-20
-4
-10
14
0
32
10
50
20
68
30
86
40
104
50
122
60
140
70
158
80
176
90
194
100
212
110
230
O
pt
imal
op
er
at
ion
C
onti
nu
ou
s o
pe
ra
ti
on
M
in
im
um
v
isc
osi
ty
f
or
sh
or
t-
te
rm
o
pe
ra
tio
n
M
ax
imum v
is
co
si
ty
at
c
ol
d s
tar
t
Viscosity,
ν
[cSt]
Temperature,
t
[°C/°
F]
DD00069413
