Tag Archives: Base Number

Setting Acid Number and Base Number Limits

Setting Acid Number and Base Number Limits There is a rule-of-thumb that oil should be condemned at double its new oil Acid Number, or at half of its new oil Base Number. The problem with this rule is that is has too many exceptions to be valid. Rather than identify the valid instances, it is…
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Know the Proper Base Number of Your Oil

Know the Proper Base Number of Your Oil The base number (BN) is a property that is more associated with engine oils rather than industrial oils. It can be defined as the oil’s ability to neutralize acids that are produced during use. The higher the base number in the engine oil, the more acid it…
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Testing the Reserve Alkalinity: Base Number

Testing the Reserve Alkalinity: Base Number Base Number (BN) testing is very similar to AN testing, except that the properties are reversed.  The sample is titrated with an acidic solution to measure the oil’s alkaline reserve.  ASTM test methods D-2896 or D-4739 are most commonly used to measure BN.  Measuring the BN can help ensure…
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