particles and heat out of the system. To ensure that hydraulic components operate without problems
and have long operating life it is therefore vital to select the correct oil type with the necessary additives.
Mineral oils for OMS, OMT and OMV motors
For systems containing Danfoss hydraulic motors mineral hydraulic oil with anti-wear additives, type HLP
[DIN 51524] or HM (ISO 11158) must be used.
Mineral oils without anti-wear additives or engine oils can also be used, provided operating conditions
are suitable.
W
Warning
It is compulsory to use oils whose inflammable degree is at least 50K above the maximum surface
temperature of the motor. Maximum surface temperature for Group IIG and IID can be found under:
T
codes and maximum surface temperature for OMS, OMT and OMV motors
on page 6.
Mixing oils of different brands or different oils of the same brand may lead to the formation of sediment
and sludge. Consequently a rapid, irreversible deterioration of the system is induced.
Temperature and viscosity
Ambient temperature
Maximum ambient temperature depends on the requested ATEX class needed – please see
T codes and
maximum surface temperature for OMS, OMT and OMV motors
on page 6.
In general the ambient temperature should be between -30 °C [-22 °F] and +90 °C [+210 °F] to ensure that
the shaft seal retains its sealing capacity.
Oil temperature
Maximum oil temperature depends on the requested ATEX class needed – please see
T codes / Maximum
surface temperature
.
Under normal operating conditions it is recommended to keep the temperature in the range of 30 °C [86
°F] to 60 °C [140 °F].
Fluid temperature affects the viscosity of the fluid and resulting lubricity and film thickness. High
temperatures can also limit seal life, at most nonmetallic materials are adversely affected by use at
elevated teperatures.
Fluids may break down or oxidize at high temperature, reducing their lubricity and resulting in reduced
life of the unit. Oil life is greatly reduced if its temperature e60 °C [+140 °F]. As a general rule, oil
life is halved for each 8 °C [46 °F] its temperature e60 °C [+140 °F].
Viscosity
Maintain fluid viscosity within the recommended range for maximum efficiency and bearing life.
Minimum viscosity should only occur during brief occasions of maximum ambient temperature and
severe duty cycle operation. Maximum viscosity should only occur at cold start. Limit speeds until the
system warms up.
User Manual
ATEX instruction for OMS, OMT and OMV
Technical information
10 |
©
Danfoss | September 2016
11160602 | AQ00000213en-US0103
