Current test standards for Cathodic Disbondment (CD) tests do not include tests that are close to or
above 100°C; primarily because of difficulties associated with evaporation of the electrolyte in such
tests and because there has been little demand for such high temperatures. However, with the
increasing use of pipelines and other vessels at temperatures above 100°C, the need for preferably
standardized tests that will evaluate coatings at these higher temperatures has become something that
needs urgent attention. Many currently used CD test standards employ methods that have both pipe
sample and testing electrolyte at the same temperature but these tests have not been viable for test
temperatures above 80°C - 90°C because of electrolyte evaporation. This paper describes the
development and testing of a high temperature test apparatus that allows for CD testing in a
pressurized test vessel. The vessel allows testing at high temperatures of electrolyte as well as
standard potential measurements and control. It also provides methods for controlling oxygen
concentration in the electrolyte. Comparative data from tests using the new apparatus and other test
methods are included that demonstrate the influence of changes in temperature, pressure, and oxygen
content in the test electrolyte. Further to this work, another CD test cell was designed, built and tested
which incorporates a cooling jacket on the cell such that high temperature CD tests can be run at
ambient pressure conditions. This paper includes discussion of the affects of oxygen concentration
levels, electrolyte temperatures, and the merits of the different CD test methods.
Key Words: CD test, high temperature, laboratory test, oxygen levels, CD electrolyte, protective
coating, pipeline coating, high pressure, cathodic disbondment, test methods