Our test procedures selected for analysing oils from refrigeration compressors have proven themselves time and time again over the years. However, we have further optmised the tests, our laboratory equipment and the sample containers for these products yet again. It‘s not just the users of modern synthetic refrigeration machine oils who are benefiting!
New analysis kits VK1 and VK2 for refrigeration compressor oils identify:
Wear metals: iron, chrome, tin, aluminium, nickel, copper, lead and molybdenum
Additives: calcium, magnesium, zinc, phosphorus, barium, boron and sulphur
Contaminants: silicon, potassium, sodium and lithium
Optical check (colour change, visible particles)
Viscosity at 40°C and 100°C as well as the viscosity index
Special outgassing process
Water content according to Karl Fischer
In addition to the tests above for analysis kit VK 2: Neutralisation Number (NN) or Acid Number (AN) or Base Number (BN)
Refrigeration compressor oils should lubricate, minimise friction, protect from wear and corrosion, cool, clean, prevent deposits and create a seal or reduce any leakage flow in the compression chamber. However, for the most part they also come into direct contact with the refrigerating agent. A refrigeration machine oil therefore has to work in harmony with it as much as possible. Impurities from seal materials or negative impacts from moisture or even water are one of the criteria for an oil change or additional oil servicing measures. The temperatures during compression of the gaseous refrigerating agent of up to 120 °C can significantly accelerate oil oxidation, hence its ageing. During an oxidation process, mostly acids form in the oil which can have a corrosive effect on the compressor components, particularly if there is any residual moisture.
The production capacity of the refrigeration compressor oil and its interaction with the refrigerating agent have decisive effects on the service life of the compressor. Therefore, regular lubricant analyses are vital. They provide information on the condition of the oil and the complex chemical reactions that have taken place in the compressor oil. If necessary, any potential damage and disruptions to operations can be counteracted.
There are special OELCHECK analysis kits for the extremely important task of monitoring refrigeration compressor oils. When the test processes in the kits were compiled, not only were our experience and the recommendations of previous compressor and oil manufacturers taken into consideration, but also the specifications of work group E-DIN 51503