A publication of
CHEMICAL ENGINEERING TRANSACTIONS
VOL. 33, 2013
The Italian Association
of Chemical Engineering
Online at: www.aidic.it/cet
Guest Editors: Enrico Zio, Piero Baraldi
Copyright © 2013, AIDIC Servizi S.r.l.,
ISBN 978-88-95608-24-2; ISSN 1974-9791
Diversity and Integration of Rotating Machine Health
Monitoring Methods
Shigeru Kanemoto*
a
, Norihiro Yokotsuka
a
, Noritaka Yusa
b
, Masahiko
Kawabata
c
a
The University of Aizu, Tsuruga, Ikki-machi, Aizuwakamatsu-city, 965-8580, Japan
b
Tohoku University, Aoba-ku, Sendai-city, 980-8579, Japan
c
TRIBOTEX Co., Ltd., Nagakusa-cho, Oofu-city, 474-0052, Japan
kanemoto@u-aizu.ac.jpr
Health monitoring for rotating machines is investigated through two kinds of mock-up experimental data
analysis. One is an anomaly mock-up test of roll bearing type rotating machine. Here, inner ring defect
anomaly is simulated and its operating data are measured by both attached type accelerometer sensor
and non-attached type microphone. Three kinds of signal pre-processing methods, frequency spectrum,
principal component analysis and cepstrum, are applied to discriminate normal and abnormal states using
several different classification algorithms, such as adaboost or random forest. Through analysis of their
performance with the help of receiver operating characteristic (ROC) curve, the importance of diversified
health monitoring methods is discussed. Another mock-up experiment is an accelerated test of roll
bearing wear. Here, acoustic emission counts, accelerometer signal and wear particle number in
lubricating oil are measured. Using these observation data, we make clear the relationships between
deterioration mechanisms of bearing and behaviour of different observations.
1. Introduction
Condition based maintenance (CBM) is one of important activities for improving both equipment reliability
and maintenance costs. The reliability is expected to increase by avoiding unnecessary overhaul or
inspections. In a viewpoint of cost, CBM would contribute not only to reduce maintenance cost but also to
allocate limited manpower to other important maintenance work. Reliable health monitoring technology is
a key issue to make CBM successful.
Based on these general backgrounds, the present paper investigates health monitoring technologies for
rotating machines in power plants. To provide reliable health monitoring technologies, it is important to
combine various kinds of sensing technologies, signal processing and data classification algorithms. Here,
the concept of diversity is important since rotating machines have various kinds of anomaly states.
However, we have to take into account that the simple diversity may induce some confusion if diversified
monitoring methodologies give different monitoring results. So, it is also important how we can integrate
the diversified monitoring results to obtain a reasonable result. Of course, we cannot expect a unique
solution for this integration process, but, it is worthwhile to investigate the diversity and integration process
by using concrete examples of health monitoring.
In the present paper, we will discuss the effectiveness of various kinds of health monitoring methodologies,
as well as the importance of integration process of diversified monitoring results, by utilizing two kinds of
mock-up experiments of rotating machine anomaly. One is an anomaly mock-up test of roll bearing type
rotating machine. Here, normal operating data are compared with inner ring defect data. The other mock-
up experiment is an accelerated test of roll bearing wear by adding excessive load on the bearing.
In these experiments, various kinds of sensing data were measured, such as accelerometer sensor data, a
non-attached type microphone data, acoustic emission data, or, wear particle number in lubricating oil.
These data are utilized to investigate what kinds of signal processing and classification algorithms are
effective to discriminate normal and abnormal states, or, to predict anomaly progress in the acceleration
DOI: 10.3303/CET1333029
Please cite this article as: Kanemoto S., Yokotsuka N., Yusa N., Kawabata M., 2013, Diversity and integration of rotating machine health
monitoring methods, Chemical Engineering Transactions, 33, 169-174 DOI: 10.3303/CET1333029
169