Copper Strip Corrosion

This is a qualitative method that is used to determine the level of corrosion of petroleum products. In this test, a polished copper strip is suspended in the product and its effect observed.

The method is well suited for specification settings, internal quality control tools and development and research on aromatic industrial hydrocarbons. It also detects the presence of harmful corrosive substances, like acidic or sulfur compounds, which may corrode the equipment. The value of this test is reported in SI units.

Copper strip corrosion is also known as the copper strip test.

This test can be used for testing gasoline, solvents, natural gasoline, kerosene, diesel fuel, distilled fuel oil and lubricating oil, among other products, using test baths. At elevated temperatures, a copper strip that has been polished is immersed in a sample, usually 30 ml.

The strip is then removed and tested for corrosion and a classification number is given. The number ranges from 1 to 4 after a comparison with the ASTM copper strip corrosion standard is done.

There are several methods and tests available. One is the test bomb bath, 7151K59. In this test a thermostatically controlled water bath is used to immerse copper strip corrosion test bombs. This must be done at the right depth as per the ASTM requirements. This test has several specifications that are identified with it:

• Testing up to four copper strips at a time.
• Maximum temperature of 221°F (±1°F)/105°C (±0.5°C).
• Using a five-gallon bath.
• Conforming to the ASTM D 130; IP 154; FSPT DT-28-65; ISO 2160; FTM 791-5325 and the DIN 51759.

Another method is using test tube baths, 7151K89 and K92. The features of this test are:

• Testing up to 16 samples at a time.
• Microprocessor control.
• Maximum temperature of 374°F (±2°F)/190°C (±1°C).
• Using a five-gallon bath and the use of water or heater transfer fluid.

This can be used to test samples which do not require a test bomb. These include diesel fuel, automotive gasoline, fuel oil, Stoddard solvent, kerosene, and lubricating oil.