Investigation of factors influencing on the autoclave tests results of internal anticorrosive polymer coatings

In the oil and gas industry the majority of equipment failure incidents are caused by corrosion. One of the effective methods for corrosion protection is usage of different coatings systems. The article presents the results of polymer powder coatings properties research that used to protect the inner wall of field pipelines. Autoclave tests were used for researching coatings properties. Autoclave studies consisted of decompression tests and HT/HP immersion tests in simulated environments. The studies were carried out in solutions containing CO2, H2S in the gas phase, as well as in the phases of combined composition. The liquid phase was 5% NaCl with different pH levels. The influence of pressure release time, exposure time, pressure release cyclicity and composition of test solution on the functional properties of the coating was studied. Systems based on polymer powder coatings were used as test samples. The work result is the clarification of the autoclave tests methodological features and the identification of factors affecting the results repeatability. Identical coating systems have been tested over a wide temperature range, showing signs of coating degradation as test temperatures increase. Also given an example of autoclave test usage as a method for detecting low quality application of paint system. The results of the work will be useful in planning a test program for the development of new anticorrosive internal pipe coatings.