Oil Types / Operating Fluids; Fluid Viscosity And Temperature For Atex / Ukex Pvm Pumps; Ambient Temperature; Oil Temperature - Danfoss Vickers PVM User Manual

User Manual
ATEX / UKEX Certified Variable Axial Piston Pumps for Industrial Applications – PVM 18 – 141 cc

Oil Types / Operating Fluids

In a hydraulic system the most important task of the oil is to transfer energy. At the same time the oil must
lubricate moving parts in hydraulic components, protect them from corrosion, and transport dirt 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.
Ratings and performance data are based on operating with hydraulic fluids containing oxidation, rust and
foam inhibitors. These fluids must possess good thermal and hydrolytic stability to prevent wear, erosion
and corrosion of pump components.
It is compulsory to use oils whose inflammable degree is at least 50K above the maximum surface
temperature of the pump. Maximum surface temperature for Group IIG can be found under
Codes with respective Maximum Surface Temperature

Fluid Viscosity and Temperature for ATEX / UKEX PVM Pumps

Table 3: Fluid Viscosity and Temperature Rating of PVM ATEX / UKEX Units
Features

Viscosity

Inlet Temperature
1) Intermittent = Short term t < 3 min per incident.
Cold start = Short term t < 3 min; p ≥ 50 bar; n ≤ 1000 min
2)
Solutions especially when the temperature is below -25 °C [-13 °F].
3) Must not be exceeded locally either (e.g. in the bearing area) . The temperature in the bearing area is
(depending on pressure and speed ) up to 5 °C [41 °F] higher than the average case drain temperature.
Above maximum surface temperatures are without any deposited dust on the product. The possible
insulation effect of a dust layer on the surface has to be taken into account by the safety margin to the
minimum ignition temperature of the dust concerned. For up to 5 mm [1.97 in] layer thickness the safety
margin is 75 °C [167 °F]. For further information please see IEC 60079-14.
The above operating temperatures (ambient and oil) of the pump must be guaranteed by the end user.

Ambient Temperature

Maximum ambient temperature depends on the requested protection class needed. Refer to
Temperature Classes at Maximum Ambient and Oil Temperatures
In general, the ambient temperature should lie between -30° C [-22° F] and +60° C [140 °F] to ensure that
the shaft seal retains its sealing capacity.

Oil Temperature

Maximum oil temperature depends on the requested protection class needed. Refer to
Temperature Classes at Maximum Ambient and Oil Temperatures
Under normal operating conditions it is recommended to keep the temperature in the range of 30 °C
[86 °F] to 60 °C [140 °F] to achieve the expected unit lifetime
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.
See
and limitations.
We recommend the use of an oil type having a viscosity of 16 – 40 mm²/s [83 – 187 SUS] at the actual
operating temperature.
8 | Vickers by Danfoss | January 2024
Warning
Minimum Intermittent
Recommended Range
Maximum (Cold Start)
Minimum (Cold Start)
Maximum Rated
Maximum Intermittend
Warning
Table 3: Fluid Viscosity and Temperature Rating of PVM ATEX / UKEX Units
on page 7.
Data
1) 10 mm²/s [90 SUS]
16 – 40 mm²/s [83 – 187 SUS]
2) 1000 mm²/s [4550 SUS]
2)
-28 °C [-18°C]
80 °C [176 °F]
1) 104 °C 3) [219 °F]
-1 (rpm); please contact Danfoss Power
on page 7.
on page 7.
on page 8 for viscosity rating
Table 2: T-
3)
Table 1:
Table 1:
BC479055194216en-000101