Condition Monitoring and Fault Diagnosis of Rolling Element Bearing in Phase Space

, M.Sc. Thesis Sharif University of Technology Karimi, Majid (Author) ; Behzad, Mehdi (Supervisor)

Abstract

The failure in rolling element bearings as an important part of rotary machine can lead to machine breakdown.Consequently, bearings can reduce reliability of these components and therefore a maintenance strategy is essential to keep reliability in a desired level. The first and primitive strategy is called breakdown or unplanned maintenance. The next is preventive or planned maintenance. In this scheme, maintenance is done after a specified time period irrespective of machine health status. Out of place maintenance is the disadvantage of preventive maintenance. The most effective generation of maintenance strategy is condition based maintenance (CBM) which suggests maintenance decision based...

Minimization of the Exit – Curvature Profile in Extrusion Dies by Optimization of the Die Profile and Application of Die Land

, M.Sc. Thesis Sharif University of Technology Khalili Meybodi, Ali (Author) ; Assempour, Ahmad (Supervisor)

Abstract

One of the most practical deformation processes has been used to produce profiles with a diversity of shapes is forward extrusion. Minimizing the extrusion pressure along with reducing the curvature of the final product have always been the main concerns of the researchers in this area. To achieve the former, researchers have designed nonlinear dies and proposed various equations to determine proper die profile. To accomplish the latter, they have used bearing at the exit section of the extrusion die. The primary object of the current study is to design a proper bearing in order to eliminate the curvature of the final product in extrusion process. The effects of both bearing and die profile...

Fault Diagnosis in Rolling Element Bearings Using Machine Learning Based on Vibration Analysis Results

, M.Sc. Thesis Sharif University of Technology Ershadi, Mohammad (Author) ; Pasharavesh, Abdolreza (Supervisor) ; Ahmadian, Mohammad Taghi (Supervisor)

Abstract

Rotating machinery plays a significant role in various industries. One of the most important and influential parts in rotating machinery is rolling bearings, which play a vital role in the proper functioning of this equipment. Therefore, bearing failures can lead to unintended equipment downtime, financial losses, and reduced productivity. As a result, accurate diagnosis of bearing faults is crucial for improving the reliability and performance of industrial machinery. Despite significant advances in the field of condition monitoring and intelligent fault diagnosis, challenges such as the lack of labeled data and the impact of noise on the accuracy of fault diagnosis models remain major...