damage cases of machinery...

Damage Cases of Machinery

Part-1

1

February 4th, 2020

Research Institute, ClassNK

Cause of machinery damage

1. Mishandling

2. Fatigue

3. Thermal stress

4. Corrosion

5. Material and structure

6. Poor maintenance

7. Outer factor (ex. Low quality fuel oil)

2

1. Introduction

Contents

4. Shafting

1 Propeller shaft

2 Intermediate shaft bearing

5. Aux. Boiler

1 Internal crack

2 Exhaust gas economizer

6. Others

1 Fire in engine room

2Fire from feeder panel

6-3 BWMS

1. Introduction

2. Main Diesel Engine

1 Crankshaft

2 Crosshead pin

3 Cylinder cover

4 Turbocharger

5 Cooling jacket

6 Damage due to F.O.

3. Aux. Diesel Engine

1 Connecting rod

2 Crankshaft

2. Damage of Main Diesel Engine

4

2-1. Crankshaft

✓ Ship type: Cement Carrier

✓ Ship age :15

✓ Kind of M/E: 4 stroke/4,300PS

✓ Damage parts : Crankshaft, Main bearings,

Crankpin bearings

2. Damage of Main Diesel Engine

No.4 Crankpin bearing No.5 Main bearing No.2 Main bearing

2-1. Crankshaft

All main and crankpin bearings were abnormal worn out and melted

5

2. Damage of Main Diesel Engine

2-1. Crankshaft

Heat crack on crank journal

No.1 crank journal

6

2. Damage of Main Diesel Engine

Waste cloth was found in check valve

2-1. CrankshaftCondition LO Line and LO filter/purifier

Inoperative

・L.O. Purifier

・ Back-flushing ofL.O. Strainer

7

2. Damage of Main Diesel Engine

2-1. Crankshaft

Cause of this trouble?

・LO inlet pressure decreased

・LO degradation

・Inoperable M/E safety device at LO lowest pressure

・Monitor and judgment based on only discharge

pressure of LO pump

8

2. Damage of Main Diesel Engine

2-1. Crankshaft

Point

・Appropriate operation of LO purifier and strainer

・No obstacle in LO line

・Maintenance of M/E safety device

・Comprehensive judgment using various

measurement results and alarms

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2. Damage of Main Diesel Engine

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2-2. Damage of crosshead pin and bearings

✓ Ship type: Bulk Carrier

✓ Ship age :15

✓ Kind of M/E: 2 stroke/8,973kW

✓ Damage parts : Crosshead pin and its bearings

Crankpin and its bearings

2. Damage of Main Diesel Engine

2-2. Damage of crosshead pin and bearings

Scratch marks on crosshead pin and its bearing

11

2. Damage of Main Diesel Engine

2-2. Damage of crosshead pin and bearings

Scratch marks on crankpin and its bearing

12

2. Damage of Main Diesel Engine

2-2. Damage of crosshead pin and bearings

M/E LO filter

Damage of LO filter element

13

2. Damage of Main Diesel Engine

2-2. Damage of crosshead pin and bearings

Cause of this trouble?

Broken steel wires of LO filter element were entered

into lubrication parts for M/E

Point

・ Proper maintenance of LO filter element in

accordance with maker instruction

・ Regular analysis of LO

14

2. Damage of Main Diesel Engine

15

2-3. Cylinder Cover

✓ Ship type: Vehicle Carrier

✓ Ship age :5

✓ Kind of M/E: 2 stroke/15,345kW

✓ Damage parts : Cylinder cover

Stud bolts/nuts for cylinder cover

Piping attached to the cylinder cover

✓ Outline of damages:

Cylinder cover was lifted. Fuel oil and cooling water

were splashed.

2. Damage of Main Diesel Engine

2-3. Cylinder Cover

Lifted cylinder cover

Approx.

45mm

Deformed packing between the cover and liner

16

2. Damage of Main Diesel Engine

2-3. Cylinder Cover

Damaged stud bolts and nuts for cover

Nut (lower side)17

Damaged thread of stud bolts

2. Damage of Main Diesel Engine

2-3. Cylinder Cover

Cause of this trouble?

Insufficient tightening of stud bolts/nuts

Point

・Confirmation of tightening torque

・Usage ofthe proper tightening tool for stud bolts/nuts

18

2. Damage of Main Diesel Engine

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2-4. Turbocharger

✓ Ship type: Water Carrier

✓ Ship age : 23

✓ Kind of M/E: 2 stroke/6,000PS

✓ Damage parts: Turbo charger for M/E

Engine Room

✓ Outline of damages:

T/C was over run and exploded. Engine room fire

was occurred.

2. Damage of Main Diesel Engine

2-4. TurbochargerOver-run- Breakage of turbine blade/blower

- Heat damage of rotor shaft/bearings

- Fracture of casing

20

2. Damage of Main Diesel Engine

2-3. Turbocharger

Broken Engine Control Room Window

21

2. Damage of Main Diesel Engine

2-4. Turbocharger

Atomizing Conditions of FO injection valve

No.5 Injection valve

22

No.6 Injection valve

2. Damage of Main Diesel Engine

2-4.Turbocharger

・Unbalanced atomization of FO valve

・Accumulation of unburned FO in exhaust pipe

Cause of this trouble?

23

M/E cylinder

Incomplete

combustion

Accumulation of unburnt F.O

Explosion

Exhaust pipe

24

2. Damage of Main Diesel Engine

2. Damage of Main Diesel Engine

2-4. Turbocharger

Point

・Appropriate maintenance interval for injection valve

in accordance with the manufacturer’s instruction

・Cleaning accumulated FO in exhaust pipe

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