RESEARCH ARTICLE Design, construction and evaluation of a device for the manufacture of ferrogram for analytical ferrography Anderson In acio Junqueira Júnior 1 | Aparecido Carlos Gonçalves 2 | Victor Hugo Ribeiro 2 | F abio Roberto Chavarette 3 | Roberto Outa 4 1 Faculty of Mechanical Engineering, UniRV - Rio Verde University, Rio Verde, Brazil 2 Mechanical Engineering Department, UNESP –University of State of Sao Paulo, Ilha Solteira, Brazil 3 Mathematics Department, UNESP – University of State of Sao Paulo, Ilha Solteira, Brazil 4 Department of Biofuels, Araçatuba Technology College – FATEC, Araçatuba, Brazil Correspondence Aparecido Carlos Gonçalves, Mechanical Engineering Department, UNESP – University of State of Sao Paulo, Ilha Solteira, Brazil. Email: aparecido.carlos@unesp.br Funding information CNPq, Grant/Award Number: 470117/2007-9; Brazilian Agencies FAPESP, Grant/Award Number: 2014/14360-1 Abstract The dynamism of the reliability of machines and equipment has the objective of availability, leading to the development of several techniques of predictive maintenance, to define the ideal point for the intervention. Among the several predictive techniques, the analysis of lubricants has its highlight. In this sense, lubricants are used to reduce friction and wear between two interacting sur- faces, filling the space of surface imperfections. In this way, wear is common even with the use of lubricating oils on the interacting surfaces. Thus, an arte- fact for ascertaining the wear particles by size in lubricating oils is analytical ferrography. In this way, this work presents the development of a low cost rotary separator prototype to obtain ferrograms, through five distinct combina- tions of permanent magnets and electronic devices. Several combinations of magnets were used and it was concluded that the 03, 04, and 05 combinations showed a better formation quality of ferrous wear particle rings. In addition, only two rings were formed in the 04 combination, but this was the best com- bination by size separation. KEYWORDS analytical ferrography, lubricant analysis, predictive maintenance 1 | INTRODUCTION Ferrography is a predictive maintenance technique that monitors and diagnoses the condition of the machine by analysing and quantifying the wear particles of lubri- cant samples in use. Through this technique, it is possi- ble to determine the performance of the lubricant, the type of wear that is occurring and the condition of the machine or equipment where the lubricant is being used. 1 Ferrography can be divided into two techniques: ana- lytical ferrography and quantitative ferrography. Quantitative ferrography presents values related to particle counting by size range. Analytical ferro- graphy uses magnetic fields to separate the wear particles from the lubricating oil for further analysis. The qualitative ferrography method can be performed using particle separators, usually linear. Rotating par- ticle separators are rare. The latter are devices that use gravitational, centrifugal and magnetic forces to make ferrograms. These devices use as a principle of operation the magnetic force exerted on the fer- rogram through the density of the magnetic flux, by means of permanent magnets with diametrical magnetization. 2 Motivated by the scarcity and high cost of these functional rotary devices, this work presents the design, construction and performance analysis of a low cost particle separator with excellent quality of particle capture. Received: 26 August 2021 Revised: 11 October 2021 Accepted: 18 December 2021 DOI: 10.1002/ls.1574 Lubrication Science. 2021;1–10. wileyonlinelibrary.com/journal/ls © 2021 John Wiley & Sons, Ltd 1