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Technical Information
Hydraulic Fluids and Lubricants
Oils, Lubricants, Grease, Jelly
powersolutions.danfoss.com
Technical Information
Hydraulic Fluids and Lubricants
Revision history |
Table of revisions |
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Date |
Changed |
Rev |
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July 2016 |
Major update. Updated for Engineering Tomorrow. |
0801 |
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November 2015 |
Minor text change. |
0703 |
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Mar 2014 |
Converted to Danfoss layout – DITA CMS |
HD |
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Oct 2002 |
New Edition |
AA |
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2 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
Technical Information |
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Hydraulic Fluids and Lubricants |
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Contents |
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General Information |
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Disclaimer............................................................................................................................................................................................ |
4 |
Introduction........................................................................................................................................................................................ |
4 |
Health, accident and environmental measures..................................................................................................................... |
4 |
API Classes of the base oil.............................................................................................................................................................. |
5 |
Hydraulic fluid features.................................................................................................................................................................. |
5 |
Viscosity.......................................................................................................................................................................................... |
6 |
Viscosity index (VI)...................................................................................................................................................................... |
7 |
Sealing compatibility................................................................................................................................................................. |
9 |
Air in hydraulic fluid................................................................................................................................................................. |
10 |
Bulk modulus.............................................................................................................................................................................. |
11 |
Compressibility.......................................................................................................................................................................... |
12 |
Water contamination.................................................................................................................................................................... |
13 |
Water solubility............................................................................................................................................................................... |
13 |
Requirements for Hydraulic Fluids |
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Fluid type-related standards and specifications................................................................................................................. |
14 |
Fluid cleanliness............................................................................................................................................................................. |
15 |
Fluid change intervals.................................................................................................................................................................. |
15 |
Traces of wear metals and contamination............................................................................................................................ |
16 |
Viscosity and temperature limits.............................................................................................................................................. |
17 |
Viscosity – Temperature diagrams.......................................................................................................................................... |
18 |
Fire Resistant Hydraulic Fluids |
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HFA fluids – oil in water emulsions, according to ISO 12 922. ...................................................................................... |
25 |
HFB fluids – water in oil emulsions, according to ISO 12 922. ...................................................................................... |
25 |
HFC fluids – water polymers / water glycols, according to ISO 12 922. .................................................................... |
25 |
HFD fluids – water free, synthetic fluids according to ISO 12 922. .............................................................................. |
25 |
General operating parameters for fire resistant hydraulic fluids.................................................................................. |
26 |
Specific operating parameters for products running with fire resistant fluids....................................................... |
27 |
Biodegradable Hydraulic Fluids |
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Biodegradable hydraulic fluids according to ISO 15 380................................................................................................ |
28 |
HETG - Triglyceride hydraulic fluids................................................................................................................................... |
29 |
HEPG – Polyglycol hydraulic fluids..................................................................................................................................... |
30 |
HEES – Synthetic ester based hydraulic fluids............................................................................................................... |
31 |
HEPR – Polyalphaolefins and related hydrocarbon hydraulic fluids...................................................................... |
32 |
Viscosity – Temperature Diagram............................................................................................................................................ |
33 |
Gear Lubricants |
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Features............................................................................................................................................................................................. |
34 |
Gear lubricants specifications.................................................................................................................................................... |
34 |
Example for selecting the kinematic viscosity - transit mixer drive (agitate mode).............................................. |
35 |
Viscosity – Temperature diagrams.......................................................................................................................................... |
36 |
Gear Bearing Grease |
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Features............................................................................................................................................................................................. |
38 |
Dropping point (ISO 2176).................................................................................................................................................... |
38 |
Miscibility of gear bearing grease....................................................................................................................................... |
38 |
Storage of gear bearing grease........................................................................................................................................... |
38 |
Consistency................................................................................................................................................................................. |
38 |
Preservation fluids and petroleum jelly |
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Features of preservation fluids.................................................................................................................................................. |
39 |
Features and application of petroleum jelly........................................................................................................................ |
40 |
© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 3 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Disclaimer
Any warranty applicable for failures related to components of Danfoss Power Solutions does not apply for any fluid related damages, unless such warranty has been expressly and specifically granted.
The rated data which is published in this Technical Information and Service Manuals is based on the use of premium lubricants containing oxidation, rust and foam inhibitors.
C Caution
It is not permissible to mix lubricants, different additive packages may cause negative interactions. If lubricant mixing cannot be avoided, fluid manufacturer’s approval is required.
Introduction
The purpose of this manual is to aid the machine operator in the selection of suitable hydraulic fluid, gear lubricants, gear bearing grease, preservation fluid and petroleum jelly.
The specifications of the lubricant manufacturer and the recommendations of the machine manufacturer are the basis for selection and subject to change without advance advice. The choice of suitable hydraulic fluids or lubricants is critical for the lifetime, operational safety and efficiency of hydrostatic components and gears.
If there are any fire hazards, see instructions in Health, accident and environmental measures on page 4.
The selection of the appropriate hydraulic fluid or gear lubricant for a specific application can be made only when the different features of the lubricants and the task and conditions under which the machine is to operate are taken into consideration. Content subject to change.
Health, accident and environmental measures
When operating units, which are filled with hydraulic fluids, gear lubricants, grease or preservation fluids (hereafter referred to as lubricants) the operator must consider, among other things, the following precautionary measures:
•Prolonged skin contact with the lubricants is to be avoided. Careful skin cleansing of sticky fluid and regular changing of with lubricant soiled work clothes is required.
•Skin contact with fluid or with heated unit parts is to be avoided, especially at temperatures over 60 °C [140 °F].
•Should lubricant get into your eyes, rinse them thoroughly with tap water and see a doctor if necessary.
•Official regulations must be observed when storing lubricants (e. g. fire extinguishers, emergency exits).
•If there are any fire hazards, the use of fire resistant fluids is recommended.
•Clean up spills to avoid slipping (e. g. normal commercial cleaning agents).
•Lubricants must not seep into the ground or get into the sewer system.
•Concrete floors as foundations can be protected against fluids by being sealed or being painted with fluid-resistant paint.
•The first time start up of systems filled with hydraulic fluid, all unnecessary personnel has to stay away from the system.
•Old or unusable fluids are to be collected. Quantities above 200 liters [53 US gal] are presently picked up free of charge in Germany by the authorized collectors, as long as prohibited foreign substances are not added to these.
•For safety reasons, the flash point of the hydraulic fluid should always be at least 20 °C [68 °F] above the maximum fluid working temperature.
•Current official regulations must be observed.
4 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
API Classes of the base oil
Fully formulated hydraulic fluids consist of a blend of a base fluid and an additive package. These base fluids are categorized by the American Petroleum Institute (API) into five groups – API 1509, Appendix E. The differentiation between them bases on the refining method, amount of saturates, viscosity and percentage of sulfur. Only groups I to III are products from the refinement of a petroleum crude.
Due to different manufacturing processes, these fluids show different content of saturates and different viscosity indices (VI). Group I to III fluids can include some VI-improvers, which result in higher VI. Group IV and V represent synthetic fluids. Thereby group IV includes polyalphaolefines (PAO) and group V all residual fluids, which do not fit into the group I-IV as example biodegradable HEES, HETG and HEPR.
Base oils specification
Oil type |
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Mineral base oils |
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Synthetic base oils |
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Group |
I |
II |
III |
IV1) |
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V |
Saturates |
< 90% |
> 90% |
> 90% |
100% |
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All other fluids, |
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including HEES, |
Viscosity Index |
80-120 |
80-120 |
> 120 |
> 135 |
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HEPG, HEPR |
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Sulfur |
> 0,03% |
< 0,03% |
< 0,03% |
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Manufacturing |
Solvent refined |
Hydrothreated |
Hydrocracked |
Synthesized |
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Process |
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Polarity |
high |
low |
unpolar |
low |
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often high |
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1) Group IV - polyalphaolefines
Hydraulic fluid features
Hydraulic fluids have the primary purpose of transferring potential or kinetic energy (pressure and movements), create volume flow between pump and hydrostatic motor, and reduce the wear of parts that rub against each other. In addition, they protect the system from corrosion and help carry away the heat produced during energy transformation.
The following tables give an outline of the requirements for hydraulic fluids:
Necessary characteristics of hydraulic fluid
Required |
Prerequisites |
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Volume stability |
adequate capacity to separate air |
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Wear protection capacity |
for a hydrodynamic or hydrostatic fluid layer between sliding surfaces |
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adequate viscosity at operating temperature |
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for all others wear reducing additives |
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Corrosion protection capacity |
non–aggressive toward customary materials and rust protection additives |
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Desirable characteristics of hydraulic fluid
Desirable |
Prerequisites |
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Only slight change in usage |
adequate oxidation resistance |
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for some cases of application adequate deemulsification capacity |
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adequate shear stability, if polymer viscosity index improvers are used |
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Viscosity–temperature behavior |
so that oil changes due to summer and winter operation become redundant |
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adequate Viscosity–Temperature behaviour |
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Interaction with seals / gaskets |
standard sealing materials can be used |
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minimal characteristics changes of standard elastomers |
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For most of the identifying characteristics listed in the table, there already exist standards or at least |
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preferred testing procedures which allow a numerical classification of these identifying features. |
© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 5 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Hydraulic fluid has to perform the following tasks:
•Energy transmission
•Lubrication
•Heat removal
When choosing a hydraulic fluid the following features are most important for consideration:
•Viscosity
•Viscosity Index (VI) and/or Viscosity Grade (VG) viscosity at 40 °C [104 °F].
•Pour point
•Shear stability, when polymer VI-improvers are used
For any application the features of the hydraulic fluid must be appropriate to the operating environment of the unit and its components.
The fundamental features of the hydraulic fluids are described below.
Viscosity
A hydraulic fluid has a low viscosity when it is thin and a high viscosity when it is thick. The viscosity changes with the temperature.
•If the temperature increases, viscosity is reduced.
•If the temperature decreases, viscosity is increased.
Hydraulic units work under extreme temperature changes, especially in heavy duty vehicles. The viscosity range of the hydraulic fluid is extremely important.
The hydraulic fluid must be thin enough to flow through the filter, inlet and return pipes without too much resistance.
On the other hand, the hydraulic fluid must not be too thin, in order to avoid wear due to lack of lubrication and to keep internal leakage within limits.
In the hydraulic business typically the kinematic viscosity 'ν' in mm2/s [SUS] is used for calculations, mainly for calculating the pressure drop in the connecting hoses and pipes.
The other measure is the dynamic viscosity 'η' in mPa•s. Dynamic viscosity is used for calculating the lubricating film thickness in a journal bearing and similar sliding films between adjacent parts.
Conversion of viscosities:
Dynamic viscosity (η) = kinematic viscosity (ν) x density (ρ): η = ν • ρ (mPa•s)
6 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Viscosity index (VI)
The viscosity index is a calculated number according to DIN ISO 2909, which describes the viscosity change of a mineral oil based or a synthetic fluid in dependence of temperature.
•a high viscosity index means a small viscosity change when the temperature changes
•a low index means a large viscosity change when the temperature changes
Viscosity – temperature diagram according to Ubbelohde representing the temperature operating range of hydraulic fluids with different viscosity index (VI).
Viscosity – Temperature diagram from Prof. Dr. Ubbelohde
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All e Recht e |
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. Copyrigh t 195 7 |
by S. |
Hirze l Verlag , Stuttgart . |
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Viscosity-Temperature |
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gung einschl. Fotokopieren |
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from Prof. Dr. L. Ubbelohde |
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S.Hirzel Verlag, Stuttgart N |
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2000000 |
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70000 |
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50000 |
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30000 |
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Hydraulic Fluid 2 |
VI 153 |
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20000 |
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10000 |
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7000 |
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5000 |
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4000 |
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3000 |
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2000 |
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1500 |
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1000 |
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800 |
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700 |
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600 |
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Hydraulic Fluid 1 |
VI 100 |
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500 |
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300 |
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200 |
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150 |
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100 |
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100 mm 2/s |
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90 |
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90 |
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80 |
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80 |
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70 |
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70 |
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60 |
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60 |
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50 |
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50 |
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40 |
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40 |
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30 |
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30 |
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25 |
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25 |
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20 |
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20 |
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18 |
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18 |
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16 |
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16 |
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14 |
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14 |
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12 |
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12 |
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10 |
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10 |
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9 |
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9 |
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8 |
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8 |
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7 |
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7 |
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6 |
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6 |
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5 |
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5 |
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4,5 |
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4,5 |
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4,0 |
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4 |
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3,5 |
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3,5 |
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3,0 |
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3 |
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2,7 |
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-50 |
-45 |
-40 |
-35 |
-30 |
-25 |
-20 |
-15 -10 |
-5 |
0 |
+5 |
10 |
15 |
20 25 |
30 |
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40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
120 |
130 |
140 |
150 160 |
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-17,78 oC (0 oF) |
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37,78 oC [100 oF] |
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98,89 oC (210 oF) |
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Temperature |
oC [oF] |
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max. 95 oC |
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P002 062E |
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Standard mineral oil based (Group I and Group II) hydraulic fluids have a VI value of 90 – 110.
© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 7 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Hydraulic fluids with a VI larger than 110, e.g. between 130 – 200, are not as sensitive to temperature change. These hydraulic fluids distinguish themselves by starting up well and having minimal loss in performance at low temperatures. At high temperatures a sufficient sealing effect and protection against wear is achieved by using hydraulic fluids with high viscosity index. The high durability of a hydraulic fluid with a high viscosity index avoids damage and machine breakdown, lowers the operating cost and increases the life of hydrostatic transmissions and units.
Shear stability
Fluids using polymer viscosity index improver may noticeably shear down (> 20 %) in service. This will lower the viscosity at higher temperatures below the originally specified value. The lowest expected viscosity must be used when selecting fluids. Consult your fluid supplier for details on viscosity shear down.
Pour point
The pour point according to ISO 3016 defines the temperature when the fluids stops to flow. Start up temperature is recommended to be approximately 15 °C [59 °F] above hydraulic fluid pour point.
Density
The density has to be specified by the manufacturer of the hydraulic fluid. Using hydraulic fluid with a high density requires the sufficient diameter of the suction line and/or elevated tank to provide positive inlet pressure.
Examples for density at 15 °C [59 °F]
Hydraulic fluid type |
Density at 15 °C [59 °F] |
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Petroleum (mineral) based fluids |
0.86 |
— 0.90 g/ml |
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Syntetic ester |
0.92 |
— 0.926 g/ml |
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Rape seed oil |
0.92 g/ml |
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Water |
1.00 g/ml |
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Polyalkylenglykol |
1.02 g/ml |
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HFC |
1.08 g/ml |
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Polyethylenglykol |
1.10 g/ml |
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HFD (phosphate ester) |
1.13 g/ml |
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8 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Sealing compatibility
The procedure for testing the compatibility of the seal material is described in ISO 6072. In general NBR (Nitrile) or FPM (Fluorocarbon, Viton) is used as seal material for static and dynamic seals. For most hydraulic fluids both seal materials are suitable, but for some hydraulic fluids only one kind is preferred. Suitable seal material allocated to the hydraulic fluid is shown in the table below. When ordering hydrostatic products the desired hydraulic fluid should be specified.
Sealing compatibility
Hydraulic fluid |
Suitable test material according to ISO 6072 |
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Mineral based hydraulic fluids |
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Water-in-oil emulsions HFB |
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Polyol esters HFDU |
Standards: NBR 1, NBR 2 and FPM 2 |
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Biodegradable synthetic esters HEES |
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Triglycerides (vegetable-oil-based) HETG |
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Poly(α-olefin) compounds and related hydrocarbons HEPR* |
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Water/glycol mixtures HFC |
Standards: NBR 1, NBR 2 |
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Alkyl phosphate esters HFDR |
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Aryl phosphate esters HFDR |
Standard FPM 2 |
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Poly(alkylene glycol) compounds HEPG |
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* Depending on the base fluid other seal material may be recommended. Please contact fluid and/or seal manufacturer for other suitable materials.
© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 9 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Air in hydraulic fluid
Air in a system is regarded as a contaminant. Air increases the compressibility of the fluid, resulting in a “spongy” system that is less responsive. Air creates a loss of transmitted power, higher operating temperatures, increased noise levels, and loss of lubricity.
Air typically enters the circuit through the suction line if the seals and fittings are not tight. This free air then may be dissolved in the hydraulic fluid. Mineral based hydraulic fluid may contain up to 9 % volume percent dissolved air at atmospheric pressure.
If 1 l [0.264 US gal] of hydraulic fluid is compressed to 100 bar [1450 psi], it may dissolve 9 l [2.377 US gal] of free air if offered.
This is not a problem unless the pressure drops down quickly to a lower level. Then the air becomes free again and bubbles show up. These bubbles collapse when subjected to pressure, which results in cavitation which causes erosion of the adjacent material. Because of this, the greater the air content within the oil, and the greater the vacuum in the inlet line, the more severe will be the resultant erosion.
The bubbles may also result in a spongy system, slow response time, and poor controllability. Therefore care must be taken to avoid air to enter the system. If air has entered a system the air release time and foam characteristic becomes important.
Air release
Air release is a measure for the time needed to release air bubbles (free air) contained in the fluid to the surfaces. Air typically enters the circuit through the suction line if the seals are not tight as explained above. Air release time is tested according to ISO 9120.
Foaming characteristic
Foaming characteristic defines the amount of foam collected on the surface in the reservoir and the air bubble decomposition time. Foaming may become a problem when air has entered the circuit as explained above, through an insufficient tight suction line. The foaming characteristic of a hydraulic fluid is tested according to ISO 6247.
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10 | © Danfoss | July 2016 |
|
520L0463 | BC00000093en-US0801 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Bulk modulus
While fluids are usually considered incompressible, the pressures that can occur in hydrostatic systems are of a magnitude that fluid compressibility can be significant. In applications that experience system pressure fluctuations resulting in random high pressure rise rates, consideration must be given to fluid compressibility when sizing a charge pump to ensure adequate charge pressure.
The amount that a specific fluid compresses for a given pressure increase is related to a fluid property known as the bulk modulus. The bulk modulus is a measure of a fluids resistance to being compressed. It depends on pressure and temperature. The air content is important as well especially below 50-100 bar [725-1450 psi]. The higher the air content the more spongy the system (lower bulk modulus). For a given pressure increase and fluid volume, a fluid with a large bulk modulus will experience a smaller reduction in volume than a fluid with a low bulk modulus.
Mathematically, bulk modulus is defined as follows:
Where:
E = bulk modulus of the fluid bar [psi] ∆p = change in pressure bar [psi]
∆V = change in volume l [US gal]
Vo = volume of oil experiencing the change in pressure l [US gal]
Units for bulk modulus are the same as the units for pressure.
Bulk modulus vs. ∆ pressure for different temperatures
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<![if ! IE]> <![endif]>Stiffer |
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<![if ! IE]> <![endif]>Spongy |
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80 |
oC [176 |
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D pressure |
bar [psi] |
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Bulk modulus increases with increasing pressure (stiffer) and decreases with increasing temperature (spongy).
Examples for bulk modulus at 22 °C [71.6 °F]
@Pressure |
Water |
HFC |
HFD |
Mineral |
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(petroleum) HF |
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140 bar [2031 psi] |
11 000 |
15 500 |
16 000 |
15 000 |
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300 bar [4351 psi] |
15 000 |
19 000 |
19 500 |
16 000 |
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© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 11 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Compressibility
Compressibility is the reciprocal of the bulk modulus. It defines how much a fluid can be compressed.
Examples for compressibility at 22 °C [71.6 °F]
@Pressure |
Water |
HFC |
HFD |
Mineral |
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(petroleum) HF |
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140 bar [2031 psi] |
91 x 10-6 |
65 x 10-6 |
63 x 10-6 |
67 x 10-6 |
300 bar [4351 psi] |
67 x 10-6 |
53 x 10-6 |
51 x 10-6 |
63 x 10-6 |
Fluid compressibility becomes a concern for a hydrostatic system which has large volumes of oil under pressure, such as long or large system lines, and experiences high system pressure spikes during operation.
To understand the nature of the problem that can be associated with fluid compressibility, consider what happens when a system experiences an increase in load. An increase in load requires more torque from the motor, and consequently, an increase in system pressure. When the system pressure increases, the fluid in the high pressure side of the hydrostatic loop is compressed.
100 bar [1450 psi]
DV
200 bar [2901 psi]
The illustration shows a simple model consisting of a cylinder whose piston compresses the fluid to create a pressure of 100 bar [1450 psi]. If a load forces the piston to move a small distance to the left, the fluid compresses even more, resulting in the pressure increasing to 200 bar [2900 psi].
The fluid at this pressure now occupies a smaller volume than the fluid did at 100 bar [1450 psi]. At the same time, the volume on the rod side of the piston increases. If we imagine that the rod side of the piston is also filled with fluid, then a void is created on this side of the piston when the fluid against the piston face is compressed. To keep the rod side of the piston full of fluid, additional fluid must be added to this side of the piston.
Calculation:
The hydraulic fluid volume under pressure in the cylinder is 10 l [2.64 US gal]. As approach the bulk modulus for 140 bar [2031 psi] as shown above is used.
12 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
Technical Information
Hydraulic Fluids and Lubricants
General Information
Water contamination
Non-dissolved water in a fluid is to be considered as contamination. It is one of the frequent reasons for the failure of a hydraulic system. Increased content of water in a lubricant can lead to corrosion of parts, water vapor cavitation, foam formation, filter clogging, oxidation of the fluid, depleting of additives and consequentially enhanced wear or a failure of the system.
Furthermore the polymer seal material could be attacked by the fluid leading to leakages.
The water contamination of the fluid can have different reasons as for example condensing of water, leakage of rain water into the system, leakage of cooling water and others.
Water solubility
Base oils of different types have limited water solubility. Blending the base oils with additives leads to a significant increase of the water solubility. Also the amount and the kind of used additive packages are crucial for this property. There is a general thumb rule: the higher the amount of additives, the higher the water solubility of a fluid. Consequently different fluid types have different water absorptive capacity, which depends on the molecular structure and the additive packages of the fluid. Some fluid types are able to dissolve more water by integrating it in the molecular structure, others less. When the absorbance of water reaches the saturation point, residual water separates from the fluid forming free water. Dissolved water in fluid is less harmfull than free water, since it is bound and has no reactivity. In case of pressure or temperature fluctuations dissolved water can get undissolved leading to an enormous change of fluid properties. The consequences of that are listed above. Strongly increased content of free water in a fluid can be detected optically, since it is leading to a clouding of the fluid.
The water in a fluid can be measured by different methods. Traditionally, Karl-Fischer-titration is used, which is used to determine the total water content. ISO 760 describes this procedure in general. Measuring the total water content means, there is no possibility to distinguish between the dissolved and undissolved water by using this method, making ppm values describing the water content often not sufficient enough.
Examples for critical water content of different fluids:
Fluid type |
Critical water content |
|
|
Mineral oil (HLP) |
200 ppm — 500 ppm |
|
|
Mineral oil with D-additives (HVLPD) |
600 ppm — 1200 ppm |
|
|
Biodegradable oil (HEES) |
700 ppm |
|
|
Fire resistant fluid (HFC=Water in Glycol emulsion) |
> 4000 ppm |
|
|
Universal Tractor Transition Oil (UTTO) |
1000 ppm — 2000 ppm |
|
|
C Caution
All numbers in this table are only rough guides, which strongly differ in dependency with the used base oil, additive packages and the application of the hydraulic system.
© Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 | 13 |
Technical Information
Hydraulic Fluids and Lubricants
Requirements for Hydraulic Fluids
Fluid type-related standards and specifications
Mineral oil based hydraulic fluids according to specification:
•DIN 51524-2: Mineral oil hydraulic fluids of category HLP
•DIN 51524-3: Mineral oil hydraulic fluids of category HVLP
•ISO 11158: Mineral oil hydraulic fluids of category HM
•ISO 11158: Mineral oil hydraulic fluids of category HV
Environmentally acceptable fluids according to specification ISO 15380 of category:
•HEES (synthetic esters) meeting Annex B of ISO 15380 (shear stability test & yellow metal test)
•HETG (tri-glycerides) meeting the same pour point specification as Category HEES and meeting Annex B of ISO 15380 (shear stability test & yellow metal test)
•HEPG (poly-glycols) meeting Annex B of ISO 15380 (shear stability test & yellow metal test)
•HEPR (poly-alpha-olefins, PAO)
Automatic Transmission Fluids (ATF) according to OEM specification
In additional to the international standards there is a variety of OEM specifications for fluids.
To meet the basic requirements for fluids all of the below mentioned ATF fluids must additionally meet the requirements of Table 3 in ISO 11158.
•GM ATF A Suffix A VI
•GM Dexron, which meets Allison C-4 and Caterpillar TO-4 test, downwards compatible with GM Dextron II or III
•Ford M2C33F and G
•Mercon V, Mercon LV
•ATF DW-1
•SP-IV or SP4
•Matic S, Matic L, Matic D
•ATF T-IV
•Toyota ATF-WS
•Honda DW
Gear Oils
In additional to the international standards there is a variety of gear oil specifications for fluids, which are described in ISO 12925-1. To meet the basic requirements for fluids both of the below mentioned gear fluids must additionally meet the requirements of Table 3 in ISO 11158.
•API GL-4
•API GL-5
Engine Oils
In additional to the international standards there is a variety of engine oil specifications for fluids, which are described in ISO 6743-15.
To meet the basic requirements for fluids all of the below mentioned engine oils must additionally meet the requirements of Table 3 in ISO 11158.
•Engine oils API Classification CI-4, CH-4, CG-4, CF-4 and CF (for diesel engines), where the latest category usually – but not always – includes the performance properties of an earlier category.
•Super Tractor Oil Universal (STOU), which meets the requirements up to API CF-4
•API GL4 with LimitedSlip (LS) additives
14 | © Danfoss | July 2016 |
520L0463 | BC00000093en-US0801 |
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