Polytropic Efficiency Improvements and Sustenance on Centrifugal Compressor: Corrosion Erosion and Impact of Fouling

Abstract

Case Study 5: This paper presents a case study on the rapid deterioration of compressor polytropic efficiency relating to systemic fouling and corrosion issues. Due to such issues, compressor service life was reduced from 10 years to only a few years. All compressor overhauls were driven by compressor polytropic efficiency drop hovering between 10 to 22%. Elemental analysis of samples collected from the internal of compressor confirmed the presence of possible fouling /corrosion. The aluminum labyrinth was the first to suffer, followed by trailing face of the impeller. Deep grooving damage was evident for 1st, 2nd and 3rd inter-stage labyrinths that were fully filled with black particles. Extensive improvement studies were conducted to manage system corrosion and liquid ingress in order to improve compressor reliability and polytropic efficiency sustenance.