Fluids for power transmission, lubricants
Corrosion and wear cause an estimated 35 million euros in unnecessary losses each year in Germany alone. Our expertise with fluids helps cut costs and save materials. Our consultation in this area goes far beyond the usual range of tests. Whether in engineering, power plants, the steel industry, mining, or the food industry – tribology becoming increasingly important in many industries.
Avoid corrosion and wear
Using optimised lubricant can reduce or avoid the huge losses. At the same time the operational reliability of machinery and equipment increases, which in turn lowers the cost of production. Our experts will help you through chemical, physical and technological studies and assessments of lubricants, hydraulic fluids, and fuels. Compatibility testing of liquids with standard elastomer or customer gaskets and corrosion tests with different metallic materials. If we check your products from us on a regular basis for consistent product quality, we award the TÜV NORD seal of approval, which then may be placed on these products.
- Hydraulic oils in accordance with DIN 51524-T1 to T3
- Hydraulic oils in accordance with DIN ISO 15380
- Turbine oils in accordance with DIN 51515-T1 to T2
- Compressor oils in accordance with DIN 51506
- Heat carrier oils in accordance with DIN 51522
- Lubricating oils for circulation and immersion lubrication (gear oils) in accordance with DIN 51517-T1 to T3
- Flame-resistant hydraulic fluids in accordance with the 7th Luxembourg Report
- Flame-resistant hydraulic fluids DIN EN ISO 12922, DIN 24320
- Test: Worked penetration according to DIN ISO 2137 – Lubricating grease, designed for extended flexing (high double stroke) and Mechanical testing in the modified FZG gear test rig according to DIN 51354-1-FZG test method A/2.8/50 for greases according to the NLGI grades 0 to 000.
- Mechanical testing in the FZG gear test rig according to DIN ISO 14635 (DIN 51354, method A / 8,3 / 90 and A/16, 6 / 90)
- Testing in Shell four-ball device according to DIN 51350 / DIN EN ISO 20623
- Mechanical testing in the vane pump according to DIN 51389/ISO 20763
- Compatibility testing of hydraulic fluids to standard testing elastomer at different temperatures and durations e.g. NBR 1, EPDM 1, FPM 1 (ISO 6072) - volume and hardness Change
- Compatibility tests vis-à-vis standard elastomers and commercially available seals (use elastomers), at different temperatures and durations, volume and hardness Change
- Corrosion tests on fluids with respect to various metallic materials (ISO 7120 / ASTM D 665, DIN EN ISO 4404. T. 1 + 2
- gap corrosion test in accordance with RAG-N 762 830 for hydraulic fluids
- Spray ignition test for hydraulic fluids according to 7th Luxemburg report, section 3.2
Such means are for example using materials which are hard to ignite and hardly spread fire or hydraulic fluids with low flammability. Testing and assessing those properties is standardized in Germany and Europe. In addition, there are international regulations which define such test methods. Following the different classification and testing standards for hydraulic fluids as well and others are described.
Specifications for hydraulic fluids in categories HFAE, HFAS, HFB, HFC, HFDR and HFDU – DIN EN ISO 12922, DGUV Regel (regulation) 113-020 and Stahl-Eisen-Betriebsblätter (SEB)
On an international level, different types of hydraulic fluids are described in DIN EN ISO 12922. They are distinguished depending on the amount of water (HFAE, HFAS and HFB) or their synthetic components (HFC, HFDR, HFDU). Each category requires – besides a lot of mechanical properties – a certain degree of fire safety. This is assessed using four different test methods which are described below.
Furthermore, national regulations, e.g. DGUV Regel 113-020 (“hydraulic hoses and fluids – regulations for safe application”), require fire-resistant fluids for use in mines, metal diecasting units and steel works with reference to DIN EN ISO 12922. The steel industry also have their own guidelines, which are listed in the so called “Stahl-Eisen-Betriebsblätter” (SEB 181 223 and SEB 181 224).
VDMA standard sheet 24317 furthermore describes technical minimum requirements for fire-resistant fluids including following test methods in reference with DIN EN ISO 12922.
The fluid's tendency to self-ignite on a hot surface is tested according to DIN EN ISO 20823. During that test, a small amount of liquid is dropped on a preheated surface (temperature depends on above mentioned categories, e.g. HFDU – 400°C) and its reaction assessed: no burning, burning on surface, burning on surface and in the tray below.
During the test according to DIN EN ISO 14935 a small rectangular piece of aluminum silicate is immersed in the liquid and then used as a wick. A small flame – similar to a regular lighter – is held to the wick for a certain time and burning behavior on the wick is assessed: does the wick continue to burn by itself and if so for how long. Pre-flaming times are gradually raised from 2 s to 30 s.
Another way of verifying the fluid’s low flammability are the spray ignition tests according to DIN EN ISO 15029 parts 1 and 2 during which the liquid is dispensed under high pressure and then impinged with a welding torch for part 1 or a stabilized propane flame for part 2. The evaluation criteria for part 1 is the afterflame time, whereas for part 2 flammability and flame length index as well as smoke density are determined. The flammability index describes a defined ratio between the temperature of the supply and the exhaust air with and without the fluid’s spray. The flame length index is also a ratio which includes the length of flame observed during the test. Last, the smoke density characterizes the intensity of the produced smoke.