Copper Corrosion test is performed to measure the corrosive property of petroleum products. ASTM D130 is a standard method used to measure copper corrosion. In gasoline, several harmful corrosive substances, like acidic or sulfur compounds, are present which may corrode the engine and other storage facilities. In the test, a copper strip is inserted in the sample for a specific time, and then strip color is compared with ASTM standard colors ranges from 1~4.
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Further study
1. https://www.nyelubricants.com
2. https://www.astm.org/Standards/D130.htm