Surveyor's day Gard/Norwegian Hull Club based maintenance.pdf · Surveyor's day Gard/Norwegian Hull Club MAN Diesel & Turbo. Bergen. October 2017. ... Debris through to crankpin bearing

1< >MAN Diesel & Turbo 2017

Surveyor's day Gard/Norwegian Hull Club

MAN Diesel & Turbo

2017 Surveyor's day Gard/Norwegian Hull Club

Bergen

October 2017

Peter M. Christensen

Superintendent Engineer


MAN | PrimeServCBM - Condition based maintenance

• Exhaust valves• Fuel equipment• Engine performance• Air supply system• Cylinder condition• Crank train bearings• Annual Service Package• Annual Extended SP• Pre-docking inspections


MAN | PrimeServCBM - Exhaust valve - corrosion countermeasures


MAN | PrimeServCBM – Exhaust valve – Damper modification

Clearance controlled and orifice controlled damper (OCD)


MAN | PrimeServCBM – Exhaust valves – Wide seat bottom piece

The modification involves:

• ”Wide” (+ 35%) seat contact width and inreased contact area with cylinder cover

New ”Wide-seat”Present ”W-seat”


MAN | PrimeServCBM – Exhaust valves – Drop down test

Unit 1 2 3 4 5 6 7 8 9 10Test ok ok ok ok x ok x x ok ok

Running hours 3617 3617 12473 3617 3529 2999 2502 7067 2312 3266

Exhaust spindle #8 dropped after 5 minutes

Non return valve / drop down check

Spindle remain closed after 30 minutes


MAN | PrimeServCBM – Fuel equipment – cleaning of fuel


MAN | PrimeServCBM – Fuel equipment – separator cleaning onboard

• Bad maintenance:

• Dirty / damaged separator bowl

• Dirty preheater

• Separators operate:

• Low temperature

• High flow

Poorly operated onboard fuel cleaning systems

Remove the cat fines continuously!

• Operate the separators:

• High temperature

• Low flow

• Clean separators and preheaters


MAN | PrimeServCBM – Fuel equipment – MC fuel pump

MC engine:Cam driven Fuel Oil Injection Pump:

• Plunger velocity governed by engine RPM

• At start conditions 15% of full load engine RPM

• Short leakage path

Test for success

• Use un-worn fuel pumps!


MAN | PrimeServCBM – Fuel equipment – ME Booster

ME engineFuel Oil Pressure Booster:

• Plunger velocity governed by supply pressure• At start conditions 75-78% of full load pressure• Long leakage path

No problem


MAN | PrimeServCBM – Fuel equipment – SL2017-638 – cleaning fuel


MAN | PrimeServCBM – Engine Performance



Pressure transducer

PMI controller

PowersupplyEnginecontrolroom

IntermediateOr frequencydivider box

Crankshaft pickupmounted at free endof crankshaft

LEDindicator

Two-stroke diesel engine



<14 >

Pure Pmax level increasePotential 5-10 barAt full as well as part loads

Reduction in Fuel oil consumption / CO2 emission

1 bar increase in average Pmax => 0.20 - 0.25 g/kWh decrease in fuel oil consumption

Reference Pmax

Potential

Potential

Balancing & Pmax level increasePotential additional 2-5 barGain even with engines already being operated within recommended limits



Compare measured service parameters with shoptest results.



Pi average +- 0.5 bar

Pcomp & PmaxPressure rise max 35 bar

Pmax & PcompAverage +-3.0 bar



Standard load diagram1. Propeller curve through optimising/

matching point (O) –layout curve for engine.

2. Heavy propeller curve – fouled hulland heavy seas.

3. Speed limit.

4. Torque/speed limit.

5. Mean effective pressure limit.

6. Light propeller curve – clean hull and calm weather – layout curve for propeller.

7. Power limit for continuous running.

8. Overload limit.

9. Sea trial speed limit.

3331353.2004.03.10 (2610/BGJ)

80 100 10585

50

70 7565 90 9560

60

70

80

90

100

Engine speed, % A

40

2

4 3

O

1

9

7

8

5

110

Engine shaft power, % A

A 100% reference pointM Specified engine MCRO Optimising/matching point

6




MAN | PrimeServCBM – Air supply system

Air

Water

Temperature


MAN | PrimeServCBM – Air supply system - WMC

~80 % ~15 % ~5 %


MAN | PrimeServCBM – Air supply system

Free water (droplets)• Lub oil break down• High wear• Liner scuffing

Evaporated Water• Black liner deposts• Higher corrosion


MAN | PrimeServCBM – Cylinder Condition – Scavenge air port inspection


MAN | PrimeServCBM – Cylinder Condition – scavenge air port inspection


MAN | PrimeServCBM – Cylinder Condition

4.8 mm

When is piston overhaul needed?

3 mm


MAN | PrimeServCBM – Cylinder Condition – filing records / observations

Piston overhaul / Liner measurementsAlways measure the “0”

point when possible

Zero measuring position


MAN | PrimeServCBM – Cylinder Condition – open up inspections

Piston open up / Overhaul


MAN | PrimeServCBM – Cylinder Condition – open up inspections

Piston open up / Overhaul


MAN | PrimeServCBM – Cylinder Condition – Specific liner wear trends


MAN | PrimeServCBM – Cylinder Condition – piston ring types

Piston rings standard can be divided into three groupsSmall Bore (26 to 50 cm Bore)Medium Bore (60 to 70 cm Bore)Large Bore (80 to 98 cm Bore)


MAN | PrimeServCBM – Cylinder Condition – 60- 80 Large bore alternative


MAN | PrimeServCBM – Cylinder Condition – 80-98 Large bore alternative

Korea, Autumn 2012, by Henrik Rolsted, LEO


MAN | PrimeServCBM – Cylinder Condition – coating thickness of Cermet


MAN | PrimeServCBM – Cylinder Condition

The original CPR (Controlled Pressure Relive) ring package with CL-grooves (controlled leakages) was introduced on all MAN B&W engines around the new millennium. This design change resulted in an tremendous improvement of the cylinder condition in general, with increased TBO. Main advantages is a better distribution of the pressures across each ring and solving the problem with overheating and collapse of the second ring.


MAN | PrimeServCBM – Cylinder Condition – monitor CL grooves

On a 46- seize engine as an example the wear potential is from 2.5 mm down to 1 mm, i.e. 1.5 mm. This require a wear rate not higher then 0,1 mm/1000h to obtain 15,000 hours TBO.

However, the wear of rings with CPR by means of CL- grooves is “unstable”. High wear of the CL-groove lead to a higher wear rate. If the CL-groove is worn below the min. limit, extremely high wear is seen, sometimes leading to scuffing!

2.5


MAN | PrimeServCBM – Cylinder Condition – small bore

The 6S40ME-B type engine after passing 10,000 service hours, and the first piston has been pulled: The top piston ring is worn down to the minimum value!

Inspection at 9,444 hours


MAN | PrimeServCBM – Cylinder Condition – small bore – POP ring

…. therefore, we have invented Controlled Pressure Relive by means of “POP” –groves (Ports on Plane)


MAN | PrimeServCBM – Cylinder Condition – video liner inspection tool

Snapshot from a S70ME – Video


MAN | PrimeServCBM – Crank train bearings – Supporting SL


MAN | PrimeServCBM – Crank train bearings – SL2008-495

Systems that facilitate condition based open-up inspections1. BWM – (Bearing Wear Monitoring)2. MBTM – (Main Bearing Temperature Monitoring)3. WIOM – (Water In Oil Monitoring)

systems are being introduced for new engines and can be retrofitted on vessels in service. When retrofitted, MAN Diesel will accept a change in the maintenance program as outlined on the next page….


MAN | PrimeServCBM – Crank train bearings – SL2008-495

• Shaft line earthing devices must be kept working and be equipped with monitoring connected to the alarm system.

• Bearing inspection scheduleDue to the higher safety against major failure, MAN Diesel considers it feasible tocompletely omit regular open-up inspections of any of the three crank-train bearingsfeaturing an approved BWM system connected to the alarm and slow-downsystem.For engines comprising an approved MBTM system, regular open-up main bearinginspections can be omitted.If the BWM, the MBTM system or other alarm indications for an abnormal bearingcondition are triggered, investigations must follow and, eventually, extraordinary open-up inspections should be carried out according to the findings.


MAN | PrimeServCBM – Crank train bearings - omit regular open-up inspections?

Know your A, B, C:A. Shaft line earthing devices must be kept working and be equipped with monitoring

connected to the alarm system.In addition it is possible to alter the bearing inspection schedule when installing:B. An approved BWM system connected to the alarm and slow-down system will

completely omit regular open-up inspections of any of the 3 crank-train bearings.C. An approved MBTM system, omits only regular open-up inspections of main bearings.In case of an alarm or indication:• If the BWM, the MBTM system or other alarm indications for an abnormal bearing

condition are triggered, investigations must follow and, eventually, extraordinary open-up inspections should be carried out according to the findings.


MAN | PrimeServCBM – Crank train bearings – XH bearings – Normal operation


MAN | PrimeServCBM – Crank train bearings – XH Bearings - TC cut out


MAN | PrimeServCBM – Crank train bearings – XH Bearings - Water in the LO

Overlay corrosion

Flash Layer (Sn)

Over layer(88% Pb 10% Sn 2% Cu)

Bonding layer (Ni og Ag)

AlSn40

Steel


MAN | PrimeServCBM – Crank train bearings – XH Bearings - Corrosion

If you see this:

All bearings will be affected & must be exchanged ASAP

Water contamination stopped, water removed

Oil analysis history recorded

Possibly advice for mounting a water-in-oil monitoring system


MAN | PrimeServCBM – Crank train bearings – unnoticed overlay corrosion

Ultimate consequence of unnoticed overlay corrosion

1. Ni layer exposed

2. Scuffing between Ni and pin

3. Scuffing between AlSn40 and pin

4. Steel-to-Steel contact

5. XH-pin & conrod bore damaged

6. Debris through to crankpin bearing

7. Crankpin bearing wiping / scuffing

8. Crankpin / bearing Steel-to-Steel

9. Crankpin severely damaged

10. Possible overheating and oilmist

11. 14 – 30 days repair


MAN | PrimeServCBM – Crank train bearings – XH Bearings

Corrosion:• Monitor Pb content in the LO.• Monitor the water content in the LO.Accelerated wear:• Savings in fuel due to slow steaming has a cost of shorter XH bearing TBO.• Monitor oil wedges for bearing metal.


MAN | PrimeServCBM – Crank train bearings – Main bearings


MAN | PrimeServCBM – Crank train bearings – Spark erosion

• Spark erosion on main bearing journal and in the lower shell

•Spark erosion on fwd trust collar


MAN | PrimeServCBM – Crank train bearings – Edge feeler

MAN Diesel does not recommend unduly opening up of bearings on 2-Stroke Diesel engines for overhaul or inspection, if they are otherwise performing well.

But…..!

It is mandatory to install a BWM systems, a water in oil (WIO) and a shaft earthing device connectedto the alarm system, in order to comply.


MAN | PrimeServCBM – Crank train bearings – main bearing – Blend Edge

Examble - The Blended Edge ”BE”, schematically and drawing specification.

The width of the ”BE” the distance from C to B at the drawing, are individual for the different engine /bearing size.


MAN | PrimeServCBM – Crank train bearings – main bearing – Blend Edge

The Blended Edge was introduced as standard in 2011.Blended edge can be used as ”repair” solution but only after consulting MAN Copenhagen.


MAN | PrimeServCBM – Crank train bearings – Crank pin bearing


MAN | PrimeServCBM – Crank train bearings – Why not open?

The human factor


MAN | PrimeServCBM – Condition based survey – CIMAC paper No. 21

In continuation of the development from visual inspections of all, to inspection based on condition it is an idea to look into the data file of gathered information as a base of maintenance planning; condition based survey

The process for the survey arrangement condition monitoring itself consists of three parts and is explained in the following using the example of crank-train bearings of crosshead diesel engines:

1. Submission of documents describing the condition monitoring systems (BWM system, water-in-oil sensor and shaft line earthing system) to be used for the survey arrangement, and compiling the correspondinginspection procedures like regular crankcase inspections required by the engine licenser. The submitted documents will be reviewed by GL experts at the head office.


MAN | PrimeServCBM – Condition based survey

2. Implementation survey on board to verify that the installation of the bearing wear monitoring system, the water-in-oil sensor, the shaft line earthing system and the implementation of the crankcase inspections in the planned maintenance system is in compliance with the engine licenser’s instructions. One month prior to the implementation survey the owner/manager has to submit an implementation report containing BWM data of at least 50 operating hours and all reports for crankcase inspections, web deflection measurements and system lube oil analyses. The implementation report will be reviewed by GL experts at the head office. A respective statement will be available for the ship owner/manager and the GL surveyor responsible for the implementation survey via the GL web portal “fleet online”.


MAN | PrimeServCBM – Condition based survey

3. Regular annual surveys harmonized with other annual surveys for maintaining the survey arrangement. One month prior to the annual survey the owner/manager shall submit an annual report containing the BWM data as XML file and all reports for crankcase inspections, web deflection measurements and system lube oil analyses carried out since the last annual survey. If maintenance or repair actions have been done, the corresponding reports have to be added. The annual report will be reviewed by GL experts at the head office. Again their statement will be available for the involved persons via “fleet online” for preparing the annual survey.


MAN | PrimeServCBM – Annual Service Package


Special Pre-Docking Inspection

Alongside by Superintendent Engineer

Fuel equipment

Cylinder condition

Visual inspection of crankcase

VAK Measurements

Complete Inspection ReportIncl. spare part recommendations

*Crankshaft deflection is supplied by vessel.

MAN | PrimeServCBM – Pre-docking inspections



Upcoming dry-dock(7-9 months)

PO for pre-inspection PrimeServ Copenhagen

Pre-Inspection

Report & Spare part offer

PO for Spare partsPrimeServ Copenhagen

Delivery

Shipping instructionsPrimeServ Copenhagen

Co-ordination with local Service Centers

Inspection reportRecommended spare parts

Spare part offerPrimeServ Copenhagen

DD ÷ 6 months

DD ÷ 5 months

DD ÷ 2 weeks

DD ÷ 3-4 weeks



Pre-docking Inspection

• Fuel Equipment

• Cylinder Condition

• VAK Measurement

Spare Parts

• What you need to ensure optimal running

• Availability• Security

Supervision (Optional)

• The knowledge of the engine designer on-site.


2017 Thank you very much for your attention

Surveyor's day Gard/Norwegian Hull Club

Documents

Surveyor's day Gard/Norwegian Hull Club based maintenance.pdf · Surveyor's day Gard/Norwegian Hull Club MAN Diesel & Turbo. Bergen. October 2017. ... Debris through to crankpin bearing