Hydraulic Fluids - Bosch Rexroth Hägglunds CA Series Installation And Maintenance Manual

Bosch Rexroth Mellansel AB, Installation and maintenance manual, Hägglunds CA 10 - CA 40, RE 15354-WA/04.2015

15.1.4 Hydraulic fluids

The hydraulic motor Hägglunds CA is primarily designed for operation with hydraulic
fluids according to ISO 11158 HM.
Fluids by the standards given in Table 26: Suggested fluid types are suggested. Before
the start of project planning, see data sheet RE 15414, Hydraulic fluid quick
reference, for detailed information on hydraulic fluids and specific additional
demands
Table 26: Suggested fluid types
SO 11158
HM
HV
Filtration of the hydraulic fluid
A contamination level of at most 18/16/13 according to ISO 4406 is required. The
less contamined the fluid, the longer the service life of the hydraulic motor.
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 Fig. 28: Selection diagram for viscosity ranges with straight fluids, i.e.
viscosity index 100
• General recommendation is to have a system temperature of 50°C, see dotted
line in Diagram 1. 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.
• Starting at above 10000 cSt imparts unnecessary strain on parts.
• Running below 30cSt may impact the service life.
• Running below 20 cSt may render instant seizure.
The operating temperature is also limited by the seal type, see Table 18: General data
(metric)or Table 20: General data (US)
ISO 15380
HEES
HEPG
HEPR
Technical data 49/52
ISO 12922
HFB
HFC
HFDU