9
Installation and Maintenance Manual, Compact CA
Technical data
2.3
Choice of hydraulic fluid
The Hägglunds hydraulic motors are primarily designed to operate on conventional petroleum
based hydraulic oils. The hydraulic oil can be chosen in consultation with the oil supplier of your
local sales office, bearing the following requirements in mind:
GENERAL
The oil shall have FZG (90) fail stage minimum 11 described in IP 334 (DIN 51354). The oil must also
contain inhibitors to prevent oxidation, corrosion and foaming. The viscosity of mineral oil is highly
dependent of the temperature. The final choice of oil must depend on the operating temperature
that can be expected or that has been established in the system and not in the hydraulic tank.
Fire resistant fluids
OPERATING WITH FIRE RESISTANT FLUIDS
The following fluids are tested for Hägglunds motors: (ISO/DP 6071)
* Many hydraulic fluids with VI-improvers are subject to temporary and permanent reductions of the viscosity.
** Low viscosity gives reduced service life for the motors and
reduction of max. allowed power for "COMPACT CA".
IMPORTANT!
Down rating of pressure data and service life must be considered when using fire
resistant fluid. The Hägglunds company or its authorised representative must always
be contacted for approval in the case of these types of fluids.
RECOMMENDED VISCOSITY AT
OPERATING TEMPERATURE
40-150 cSt/187-720 SSU.
FOR SPEED BELOW 5 RPM, COATED
PISTONS OR HIGH VISCOSITY SHALL
BE USED.
High temperatures in the system greatly reduce
the service life of oil and rubber seals, as well
as resulting in low viscosity, which in turn
provides poor lubrication.
Content of water shall be less than 0,1%.
In Industrial applications with high demands
for service life, the content of water shall be
less than 0,05%.
* Must be specified in the order.
**The motor must have synthetic oil for the axial bearing.
Viscosity limits
Viscosity index
= 100 recommended
= 150* for operation
with large temperature
difference
Min. permitted in continuous duty
Min. permitted in intermittent duty
Max. permitted
40 cSt/187 SSU
0 cSt/98 SSU**
10000 cSt/48000 SSU
Temperature limits
Normal operating temperature should be less
than +50°C (1°F)
Nitrile seals (std motor)
Viton seals
-35°C to +70°C
-0°C to +100°C
Nitrile seals (std motor)
Vition seals
-31°F to +158°F
-4°F to +1°F
Fluid
Approved
Seals
Internal paint
HFA: Oil (3-5%) in water emulsion
No
-
-
HFB: Inverted emulsion 40-45% water in oil
Yes
Nitrile (std motor)
Not painted*
HFC: Water-glycol
Yes
Nitrile (std motor)**
Not painted*
HFD synthetic fluids
HFD:R - Phosphate esters
Yes
Viton
Not painted*
HFD:S - Chlorinated hydrocarbons
Yes
Viton
Not painted*
HFD:T - Mixture of the above
Yes
Viton
Not painted*
HFD:U - Other compositions
Yes
Viton
Not painted*
