Seal wear debris characterization for predictive maintenance

It has been estimated that at least 30% of the maintenance expenditures of large refineries and chemical plants are spent on pump repairs. In turn, each dollar spent on pump repairs contains a 60 or 70 cents outlay for mechanical seals. Seal failure reduction is therefore a priority assignment for mechanical technical service personnel in the petrochemical industry. In general, careful examination is possible only if the entire failed seal is available. However, this specific circumstance is very rare. It was, therefore, in this particular research to propose a preliminary assessment through a systematic statistical design of experimental studies of the NBR rubber debris inspection for sliding wear: namely adhesion, abrasion, after acid attack and swelled NBR rubber specimens that point to further clues and lead to the root causes of most mechanical seal problems. A series of tests were conducted with NBR rubber specimens vs cast iron wheel. NBR rubber wear particles were systematically studied in a particular block-on-ring tribosystem to assess wear products both worn surfaces and wear debris morphology. Specifically, NBR wear debris morphology obtained through an optical microscope was used to classify NBR wear debris in conjunction with their generating wear modes/mechanisms. Implementation of such results from this particular work is a basic foundation in the study of the seal wear process and essential in the evaluation of the deterioration state of this specific tribosystem. Study of seal wear particles can then be applied for predictive maintenance.