Review of Coating Technologies for Centrifugal Compressors

The turbomachinery industry for petrochemical processing and ethylene production has roots that trace back many years, and this had developed tried and true designs which are manufactured from well established materials. Given the success of the centrifugal compressors in these applications, customer have come to expect reliability and longevity from their equipment. The challenge that is faced by operators and OEMs is how to increase the operating time between shutdowns while allowing the compressor to maintain optimal operating efficiency during the entire operating time. Coatings have been applied to both the rotating and stationary equipment with centrifugal compressors to help maintain this operating efficiency by both preventing the adhesion of foulant from the process gas and providing corrosion protection to the base metal of the components. This presentation will review the state of the industry for corrosion and anti-fouling coatings that have been used in centrifugal compressor applications in ethylene production. The focus will be on the types of the coatings that are available along with benefits and drawbacks associated with each type of coating. This presentation will also review the application process of the coatings which can also influence the coating selection for a specific rotor or stationary component. The industry experience with each type of coating will be reviewed.

As there are increasingly more demanding applications for centrifugal compressors, the development of new coatings with improved properties is always necessary. The types of testing that can be performed for coatings will be discussed. This includes testing for not only the anti-fouling properties of the coating, but testing of the chemical resistance and the types of testing that may be required in various applications, testing for adhesion strength and even the durability to solid particle and solid particle resistance.