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Environment & Engine Control

CM Technologies

Acid Number Test

Acid Number or AN is a vital oil parameter for hydraulic systems and gas engines. It is a measure of the organic and inorganic acids present within the oil.

Price and delivery time will be given on request
Range 0...6 AN
Test Time 2 minutes
No. of Tests 25
Reagents UN1993
Electronic Acid Number Test Kit
Range 0...6 AN

The CMT Acid Number Test (AN Drop Test Kit) comes with all necessary reagents and equipment for a fully portable Acid number test. The acid test is based on a chemical titration test. Drop by drop is added from a dropper bottle into a test jar. The number of drops does represent the AN number of the oil.

Atmospheric oxygen constantly reacts with oils producing organic oxidation products that are acidic in nature. This reaction is very slow at ambient temperature and has little effect upon oil conditions. As a result, acid Number oil analysis or AN gives the user both the weak organic and solid inorganic acids present in the oil as a total acid number. It applies to gearboxes, gas engines, gas turbines and hydraulic lubricants.

Acid Number oil analysis (AN) is not generally associated with engine crankcase lubricants unless severely contaminated. The singular exception to this may be crankcase lubricants for gas engines. In this instance, AN can deplete very rapidly, and elevated operating temperatures can generate high levels of weak organic acids.

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Want more information?

Get in touch with Erik-Jan our CMT specialist


Erik-Jan Visser

Account-/ Product Manager


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General contact

Driemanssteeweg 190
3084 CB Rotterdam
The Netherlands