Thrusters

Health Monitoring of Propulsion and Steering Devices

Arthur BoogaardEddy Engels

Albert Wesselink

Wärtsilä Propulsion The Netherlands

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1

Condition based maintenance of Steerable Thrusters

Dynamic Positioning Conference 2005

Houston, Texas

Arthur BoogaardEddy Engels

Albert Wesselink

Wärtsilä Propulsion The Netherlands

2

Contents

Introduction Wärtsilä PropulsionSteerable Thrusters design philosophyFailure cases and results of malfunctionsHealth Measuring of Steerable ThrustersCommunicationConclusion

3

Wärtsilä Propulsion

Propulsion Products Brand name LIPS

4

Health monitoring Wärtsilä engines

saving fuel consumption

increase maintenance intervals

extend lifetime of components

5

Design philosophy LIPS steerable thrusters

Double supported pinion and gear wheels

High quality forged steel gearwheels machined after hardening: Klingelnberg cyclo palloid HPG process

Separate dedicated bearings for axial and radial loads

Triple Viton lip type seals running on liners with ceramic coating

Product range 900 kW – 7.000 kW

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What can go wrong

Seal damage: water content in lub oil reduces the life time of bearings and gears with 50%.Inadequate lubrication due to late filter / oil changeOverloading of the thrusterExternal impacts

Eventually this leads to early wear of gears and bearingsWear particles spread through the unit and affect other “healthy” components

THE HEALTH OF THE THRUSTER SLOWLY BUT STEADILY DETERIORATES

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Results of malfunctions

Unplanned maintenance / repairs

Replacement parts

Loss of redundancy (Class)

Docking

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Where to go

• pressure• oil• temperature• level

early detection ofdeteriorating components • vibrations• moisture• particles

result: signals• make trend line

• combine signals, remaining lifetime

• database

alarms monitoring diagnostics/prognostics

today tomorrow future

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From alarming…

temperature alarmslubricationsteering

pressure alarmspumpssteering motorsfilters

levelgearboxesheader tanks

Rely on expertise on board, Wärtsilä’s serviceAlarm: (too?) late, not source related

10

… to monitoring…

Add sensors to systemAccelerometersMoisture sensorsParticle detector

With signals:

Detect early changes in behaviour Establish trend lines

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Sensors (1/2)

Accelerometers:damage to race way / roller elementdamage to gearing

vibration

determine frequencies → relation to damaged element

signal analyzing

0

0 .1

0 .2

0 .3

0 .4

0 .5

0 .6

0 .7

0 .8

0 .9

1

0 50 10 0 150 2 00 2 50 30 0frequency [Hz]

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Sensors (2/2)

Moisture sensor:water affects gear and bearings decrease of lifetime

Particle sensor:detection wear bearings, gearingcross reference to other sensors

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Human interface

Off-line monitoringRobust softwareFit to purposeEasy to useTrend watching

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Health monitoring

local readout of individual signals

health gears

health bearings

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… to (in future) diagnostic/prognostics…

Use data from monitoringAdd “belief” rules, expertise from practiceBuild neural networkSelf learning system

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Health diagnostics system

SIGNAL MODULATOR

TRANSMITTER

ELECTRICPOWER

GENERATION

RECEIVER / TRANSMITTER

Accelerometers nearRoller Bearings

Accelerometers near(Bevel) Gears

Oil Moisture andParticle sensors

Pitch actuating pressures

ELECTRICPOWER

GENERATION

GE

AR

BO

XS

TEM

SE

CTI

ON

In ro

tatin

g pa

rt

RECEIVER / SIGNAL DEMODULATOR

ACTUAL

DEMANDED

PIT

CH

AZI

MU

TH

RP

M

PIT

CH

AZI

MU

TH

RP

M

GP

SP

RE

SS

. CW

PR

ES

S. C

CW

LOG-FILEEnvelope spectraRoller Bearings

Envelope SpectraGears

OIL

TE

MP

.

AM

B. T

EM

P.

Oil dataprocessing

Responseidentification

DATA FUSION & DECISION SUPPORT

SHIP NETWORK

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Conclusion

Today: alarmsperiodical maintenance / operating hoursalarms

→ actions too early / (too) late

Tomorrow: monitoring:early detection of deteriorating componentsless unplanned dry-dockingdecrease down timedecrease stock

→less “surprises”, saving money

Diagnostics/prognostics: in future