Introduction of a System for Detecting
Abnormal Vibration in Shipboard Equipment～The Potential of Abnormal Vibration Detection Systems for Preventive Maintenance～
1. Introduction

problems.

The Japanese economy is supported by import /export

Recently, with the improvement in technology for

trade and international sea transport accounts for overtemperature, pressure and vibration sensors, systems

90% of total import /export cargo. Transport bythat automatically monitor various inspection items andWinter 2019shipping is an extremely important method for

issue warning on abnormalities are installed, but theconducting international trade.

actual situation is that not all the small behavioral

With the expanding global economy and borderless-changes and abnormal vibrations of onboard equipment

ness, it is becoming apparent that global risk is

could be automatically monitored sufficiently.

intricately interconnected. Sea transport businesses are

In this report, we would like to introduce a portable

always at the brink of danger and they aim to prevent

system which detects abnormal vibrations that wasserious accidents. To conduct safe transport whiledeveloped together by MOL Techno-Trade, Ltd. andmaintaining a transport schedule, not only maintenanceValqua as a collaboration.

management to safely operate vessels, but also various
efforts towards safe operation of the vessel and marine

No.36

five human senses were mainly relied upon to findenvironment maintenance are being taken.
The important basics for maintaining safe operation of2. ‌Efforts toward preventive
maintenance of equipment

vessels are appropriate monitoring by the navigation

２-1）
Monitoring of status of onboard equipment

officers and selection of an optimal route taking

The operational status such as the temperature, pressure,

weather and sea conditions into consideration.

rotation rate, etc., of each part of major equipment

Important equipment for operation such as the main

onboard, such as the main engine, power generator,

engine that propels the vessel, power generator andboiler, etc., are automatically monitored at all times.

auxiliary engines such as various pumps, fans andThis is periodically recorded in the data logger

motors are located in the engine room, which isinstalled in the engine control room, and when an

monitored by the engineer who also manages preventive

abnormality is detected, a warning is issued regardlessmaintenance.

of the time, which automatically slows down or initiates

To prevent serious damages beforehand, the operationalan emergency shut-down, and for equipment with astate of the various engines and equipment in the

back-up function, the substitute equipment will startengine room are patrolled and inspected daily toautomatically to avoid any operational disruptions or

discover any abnormalities, and early actions such as

major equipment damage.

overhaul inspections are extremely important.

However, small rotating equipment and motors thatIn previous times, only the bare minimum of monitoring

run fans and pumps are not equipped with sensors todevices for equipment installed on vessels were available

monitor their operational status. Overheating, abnormal

and during the patrol to inspect the engine room, thesounds and vibrations due to wearing out of motor3

C u s t o m e r S o l u t i o n s《 J o i n t A u t h o r s h i p 》

bearings are inspected by relying upon the five senses

does not require any conversion to be used for allof the engineers during periodic patrols using touch

onboard equipment. It is an easy-to-use monitoring tooland listening rods. If the discovery of abnormalities ist hat ca n conduct w i reles s d ist a nce v ibrat ion

delayed, this may lead to the burning of the motor due

measurements of equipment installed in places that are

to damage to the bearing. The current situation is that

dangerous or in high places where access is restricted,

preventive maintenance such as periodic opening

and it has noise-cancelling features that enables it tomaintenance based on operational time is conducted for

eliminate disturbance vibrations that are generated

main equipment onboard.

from equipment other than the measurement target
and has an addition of a wireless detection feature. The２-2）Use of big data onboard

system composition is anticipated to be used not only

Recently, the voluminous data obtained from status

for onboard equipment in vessels, but also widely used

monitoring can be monitored around-the-clock on landfor preventive maintenance of equipment used in theby using a satellite link. Efforts towards improving safe

track & field industry and industrial plant relatedoperation are being conducted by combining this withequipment.

weather and sea condition data, selection of an optimalroute to decrease the burden on the vessel andpropulsion engine, and utilization of optimal automaticnavigation, etc.

3-1）F unctions and characteristics of thevehicles are being vigorously pursued by automobile

vibration detection maintenance systemmanufacturers, and technical development of anThis system is currently undergoing validation on an

autonomous navigation vessel（automated ship）has also

actual vessel. As described above, it does not require

started for ships. In the beginning of 2020, a test

conversion to monitor equipment status and it isvoyage to conduct actual validation is scheduled, so incurrently undergoing validation as a system that canaddition to weather and sea condition information,measure and monitor equipment vibration without

various big data such as information on navigational

being affected by vibrations due to rocking.

meters（radar, collision prevention device, electronic

Figures1 and 2 show the external appearance of themarine maps）and status monitoring information

vibration detection maintenance system and Table1

within the engine room, etc. are becoming even moreshows the major specifications of the main section ofimportant elements to promote autonomous navigation.

the system.

However, currently, not all onboard equipment is

The sensor part for detecting vibration utilizes aautomatically monitored and a tool that can measurefluorine resin and is intended to be used for locations

the status of equipment, confirm the presence/absencewith high temperatures such as pumps and has heatof abnormalities, and make decisions is anticipated. In

resistance in 100℃ environments. To enable easy

particular, for onboard equipment, different frominstallment regardless of the shape of equipment, it canequipment installed on ground, the location itself wherebe attached by tape and magnets.

the equipment is installed may rock or be affected by

The signal from the sensor is transmitted through thevibrations from other installed equipment and in thiswireless dock and received by a tablet terminal locatedenvironment, it is very difficult to measure andaway from the equipment and whether there aremonitor abnormal vibrations of the equipment itself.

abnormalities can be confirmed as chronological changes.

The newly developed "System to detect abnormal

It is also possible to directly connect the sensor andvibrations in marine equipment" considered suchtablet with a cable for measurements.

environment which such equipment is placed in, andOn the functional side, it has a function that analyzes
4Winter 2019Technical development on automatic operation of

3. Summary‌of vibration detection
maintenance system

No.36

Introduction of a System for Detecting Abnormal Vibration in Shipboard Equipment～ The Potential of Abnormal Vibration Detection Systems for Preventive Maintenance ～the pattern of rocking of the vessel and equipment andTable1

the amplitude as vibration frequency. It reduces thevibration effect（disturbance vibrations）by rocking of ajor specifications of the main section of theMsystem

Display section 10-inch tablet（touch panel）

the vessel, and by distinguishing it from vibrations ofthe equipment itself, it conducts continuous vibration

Ch No.

４ch or ２ch / amplifier
Max. 12ch（wireless connection with ４ amplifiers）

OutputSD card slot（SDHC compatible, Max. 32GB）

monitoring of the equipment.

Water resistant IP54 waterproof equivalentUse range

Size and weight−10℃ to 50℃ , under 90% RH（with no condensation）
40（H）x275（W）x188（D）mm
1200g（includes Li-ion battery, 280g）

Radio Law approved（Europe, US, China, Japan）［Scheduled］ CE marking, WEEE directive
Chinese version of RoHS

Figure1

Winter 2019

External appearance of the vibration detection
maintenance system
Left：Tablet
Upper right：Sensor（Approximately 2cm square）
Bottom right：Wireless dock（amplifier）

3-2）Examples‌of validation experiments on
reduction of disturbance vibrations
A validation using experimental methods was triedregarding the effects（disturbance vibrations）due tothe navigational environment of onboard measurements,
such as the wind and waves at the time of operation.
A vibrator device was used as the source for disturbancevibrations, and the motor was setup on a vibrating

No.36

platform to confirm whether it would be possible todistinguish between disturbance vibrations and motor
vibrations. The vibrator device was i2 4 0SA3M（manufactured by IMV）using 5Hz, 5mmp-p conditions
to vibrate in the z-axis direction （up and downvibrations）. The motor was a Superline single-phasemotor（SC-KR-100W-4P-100V）under the condition of1720 rpm（28.7 Hz）and was installed and fixed so themotor rotational axis was perpendicular to thevibration direction. Measurement results are shown in
Figures3 and 4.
Figure2 hin film fluorine resin organicTpiezoelectric element

According to Figure3, motor vibrations are affected bydisturbance vibrations and compared to when thevibrator is turned off, the signal intensity at 5 Hz,
which is the additional vibration conditions, increases
and significantly changes（approximately 50 dB）invibration level. On the other hand, if disturbancevibrations are reduced, the increase in vibration

5

C u s t o m e r S o l u t i o n s《 J o i n t A u t h o r s h i p 》

No disturbance vibration reduction

Motor vibration during
vibration excitation

Motor vibration when not vibrating

Figure3 Motor vibration band affected by vibrator vibrations

With disturbance vibration reduction
Motor vibration during
vibration excitation

Motor vibration when not vibrating

Motor vibration band when effect of vibrator
vibrations is reduced

intensity at 5 Hz was confirmed to be within 5 dB
（Figure4）. Similarly, the results of the effect ofFigure5‌An example of vibration measurement results onan actual vessel（seawater cooling pump）

Winter 2019

Figure4No.36

4. Summary

disturbance vibrations were under 5 dB even if

With the developed system, it was possible to confirm

measurements were under the conditions such as whenreduction of disturbance vibrations in the validation

the additional vibration amplitude was changed（5 Hz:

study at the laboratory level. In addition, a difference in

5,7, 10mmp-p）or the additional vibration frequency

t emp or a l s ig n a l i nt ens it y wa s c on f i r med by

was changed（75 Hz: 0.03, 0.05mmp-p, 200 Hz: 0.005,

measurement on an actual vessel.

0.007 mmp-p）. This suggests the possibility of reducing

However, in actual navigation, it will be necessary to

the effect of waves during navigation.

measure the vibration status with everchanging
surroundings and environment, such as main power

3-3）
Measurement example on an actual vesseloutput, loading conditions that differ between outboundFigure5 shows an example of measurement results of aand inbound trips, operational status of auxiliary

seawater cooling pump on a coastal tanker（Technostar）

equipment, etc.

owned by MOL Techno-Trade, Ltd. Temporal changes in

Aiming for the main validation study, while confirming

the signal intensity can be seen. Measurements are toand considering the effect of a wide variety of

be continued while considering the effect of disturbance

disturbance vibrations, detecting the status changes invibrations in preparation for the main validation study.

equipment vibration and setting the appropriate cut-off
value are our future challenges.
6Introduction of a System for Detecting Abnormal Vibration in Shipboard Equipment～ The Potential of Abnormal Vibration Detection Systems for Preventive Maintenance ～5. Conclusions

maintenance parts. By continuing our validation study,
we would like to produce a system that visualizes theIt is considered effective for vessels operating on sea

states that differ from the normal state and deliver aaway from land to conduct appropriate maintenancepredictive maintenance effect that would contribute tomanagement that includes keeping track of defects andsafety and security throughout the whole industrial

breakdown trends of individual equipment and stocking

field regardless of land or sea.

Makoto Haneda
Managing Director
MOL Techno-Trade, Ltd.

Winter 2019

Tetsuya Komeda
Corporate Research andDevelopment Group
Product Development DivisionⅠ

No.36

7Hisataka Sato
Corporate Research andDevelopment Group
Product Development DivisionⅠ

Yasushi Aburatani
Corporate Research andDevelopment Group
Advanced Technology
Reseach Division