condition monitoring in marine industry

1. CONDITION MONITORING OF NAVAL SHIP
Presented by
A. Sabiha Khathun
M.TECH (Machine Design)
16481D1501
Subject: condition monitoring
GUDLAVALLERU ENGINEERING COLLEGE
Sheshadri Rao Knowledge Village,
Gudlavalleru,PIN:521356

2. Introduction
What Is Condition Monitoring?
• Condition monitoring (CM) is the process of monitoring a
parameter of condition in machinery (vibration, temperature etc.)
in order to identify a significant change which is indicative of a
developing fault. It is a major component of predictive
maintenance.

3. What and when to monitor
• Traditionally quantities, such as line currents and voltages, coolant
temperatures, and bearing vibration levels, have been measured and will
continue to be used.
• Other specialist methods, involving the accurate measurement of rotational
speed or the sensing of leakage fluxes, are being developed in order to
monitor a variety of fault conditions.
• One should monitor when it is cost-effective to do so, or when there are
over-riding safety considerations to be observed. The assessment of cost-
effectiveness can be a relatively complex matter

4. CM Techniques
• The following list includes the main condition monitoring techniques
applied in the industrial and transportation sectors
• Vibration Analysis and diagnostics
• Lubricant analysis
• Acoustic emission (Airborne Ultrasound)
• Infrared thermography
• Ultrasound testing (Material Thickness/Flaw Testing)
• Motor Condition Monitoring and Motor current signature analysis (MCSA)
• Model-based voltage and current systems (MBVI systems)

5. Naval ships

6. CM IN MARINE INDUSTRY
• Condition Based Predictive Maintenance(CBPM) is an effective
tool in monitoring the heartbeats of a machinery. CBPM is an
advanced tool in predicting the behavioral patterns of machinery
components.
• Ships of more than 12 years old shall be considered as posing a
higher risk.
• Depending on the type of vessel, these may range from a full ship
analysis using a complete structural direct analysis to the analysis
of individual elements such as shaft alignment and vibration.

7. • The measurements include parameters such as temperatures
and pressures for various machinery equipment and systems
located in the engine room of the vessel.
• Naval ships unlike merchant ships consist of complex
machinery and are subjected to rigorous exploitation pattern
owing to war deployments. This results in early wear and tear
of machinery.
• CBPM strategy can be utilized in systematic monitoring of
equipment fitted onboard ships and enable implementation of
E-maintenance strategy.

8. • In order to better understand the philosophy behind the
inspection requirements, ship structural components presented
here.

9. Ship hull failure

12. Which failures can be diagnosed with
vibration analysis
• Bearing wear and lubrication
• Misalignment
• Bend shaft
• Resonances
• Flow related problem (cavitations )

13. VIBRATION MONITORING
• Vibration monitoring first begins with acquiring an accurate time-varying
signal from a vibration transducer, such as an accelerometer.
• Narrowband analysis
Narrowband analysis is basically the analysis of FFT spectrum in a close
band of frequencies to determine the vibration frequencies present and
how these vibration frequencies relate to the rotating speed (rpm)of the
various machine components
• signal analysis
Time-varying signal and splitting it into components, each with an
amplitude, a phase, and a frequency.

15. FACTORS AFFECTING SHIPS STRUCTURAL
INTEGRITY
The term "structural integrity" as used here is intended to
convey the employment of structural design, material
utilization, and fabrication technologies in the production of a
ship.
• Load,
• corrosion,
• weld ability,
• material selection.

16. HULL GRIDER

17. Hull Girder:
• The main functions of a ship's hull girder are to act as a
watertight envelope, to support local hydrostatic loads, and to
resist the bending loads applied on the structure.
• Lot of marine accidents that involved failure of the hull
structures. Whether it was a crack in the midship region, failures
due to propagation of cracks
• Mostly, crack propagation takes place due to fatigue,

18. Ultrasonic Thickness Measurement (UTM)
• In the field of transportation, ultrasonic testing, ultrasonic
thickness measurement(UTM) is a method of performing
nondestructive measurement (gauging) of the local thickness of
a solid element (typically made of metal, if using ultrasound
testing for industrial purposes) basing on the time taken by the
ultrasound wave .

19. • The INCASS project aims in integrating robotic platforms,
structural and machinery reliability tools in order to enhance
ship inspection, maintenance, safety and performance.
• Structural components such as main deck plating, butts
and seams are checked. It uses non-destructive techniques
such as ultrasonic method and magnetic particle methods
for its measurements and analysis. All the welds are tested.

20. Maintenance oriented strategy onboard
naval ships
• A suitable software should be developed to incorporate the details of
equipment and just clicking on a particular equipment will give all
the maintenance activities carried out and also indicate ships fitted
with same equipment.
• The maintenance activity onboard a naval ship can be undertaken by
developing suitable software to integrate the measurements
undertaken on a mechanical component with electronic equipments.

22. Infrared Thermography

23. Acoustic emission

24. REFERENCES
• [1]. P.TAVNER, L.RAN, J.PENMAN , H.SEDDING,
‘Condition Monitoring of Rotating Mechanical Machines’
2008 – Book
• [2]. TAVNER .P.J ‘ Review of condition monitoring of rotating
electrical machines’, IET Electric Power Applications,
November 2007.