MAN Diesel & Turbo. Surveyor's day Gard/Norwegian Hull Club. Surveyor's day Gard/Norwegian Hull Club Bergen October 2017

Transcription

1 Surveyor's day Gard/Norwegian Hull Club 2017 MAN Diesel & Turbo Surveyor's day Gard/Norwegian Hull Club Bergen October 2017 Peter M. Christensen Superintendent Engineer < 1 >

2 CBM - 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 < 2 >

3 CBM - Exhaust valve - corrosion countermeasures < 3 >

4 CBM Exhaust valve Damper modification Clearance controlled and orifice controlled damper (OCD) < 4 >

5 CBM Exhaust valves Wide seat bottom piece The modification involves: Wide (+ 35%) seat contact width and inreased contact area with cylinder cover Present W-seat New Wide-seat < 5 >

6 CBM Exhaust valves Drop down test Spindle remain closed after 30 minutes Non return valve / drop down check Exhaust spindle #8 dropped after 5 minutes Unit Test ok ok ok ok x ok x x ok ok Running hours < 6 >

7 CBM Fuel equipment cleaning of fuel < 7 >

8 CBM Fuel equipment separator cleaning onboard Poorly operated onboard fuel cleaning systems Remove the cat fines continuously! Bad maintenance: Dirty / damaged separator bowl Dirty preheater Separators operate: Low temperature High flow Operate the separators: High temperature Low flow Clean separators and preheaters < 8 >

9 CBM 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! < 9 >

10 CBM Fuel equipment ME Booster ME engine Fuel Oil Pressure Booster: Plunger velocity governed by supply pressure At start conditions 75-78% of full load pressure Long leakage path No problem < 10 >

11 CBM Fuel equipment SL cleaning fuel < 11 >

12 CBM Engine Performance < 12 >

13 CBM Engine Performance Pressure transducer PMI controller Engine control room Power supply LED indicator Intermediate Or frequency divider box Crankshaft pickup mounted at free end of crankshaft Two-stroke diesel engine < 13 >

14 CBM Engine Performance Reduction in Fuel oil consumption / CO 2 emission 1 bar increase in average Pmax => g/kwh decrease in fuel oil consumption Reference Pmax Potential Potential Pure Pmax level increase Potential 5-10 bar At full as well as part loads Balancing & Pmax level increase Potential additional 2-5 bar Gain even with engines already being operated within recommended limits < 14 > < 14 >

15 CBM Engine Performance Compare measured service parameters with shoptest results. < 15 >

16 CBM Engine Performance Pi average bar Pcomp & Pmax Pressure rise max 35 bar Pmax & Pcomp Average bar < 16 >

17 CBM Engine Performance Standard load diagram 1. Propeller curve through optimising/ matching point (O) layout curve for engine. 2. Heavy propeller curve fouled hull and heavy seas. Engine shaft power, % A A 100% reference point M Specified engine MCR O Optimising/matching point 5 O 7 3. Speed limit Torque/speed limit Mean effective pressure limit Light propeller curve clean hull and calm weather layout curve for propeller Power limit for continuous running. 8. Overload limit. 9. Sea trial speed limit Engine speed, % A (2610/BGJ) MAN Diesel & Turbo 2017 < 17 >

18 CBM Engine Performance < 18 >

19 CBM Air supply system Water Air Temperature < 19 >

20 CBM Air supply system - WMC ~80 % ~15 % ~5 % < 20 >

21 CBM Air supply system Free water (droplets) Lub oil break down High wear Liner scuffing Evaporated Water Black liner deposts Higher corrosion < 21 >

22 CBM Cylinder Condition Scavenge air port inspection < 22 >

23 CBM Cylinder Condition scavenge air port inspection < 23 >

24 CBM Cylinder Condition When is piston overhaul needed? 3 mm 4.8 mm < 24 >

25 CBM Cylinder Condition filing records / observations Piston overhaul / Liner measurements Always measure the 0 point when possible Zero measuring position < 25 >

26 CBM Cylinder Condition open up inspections Piston open up / Overhaul < 26 >

27 CBM Cylinder Condition open up inspections Piston open up / Overhaul < 27 >

28 CBM Cylinder Condition Specific liner wear trends < 28 >

29 CBM Cylinder Condition piston ring types Piston rings standard can be divided into three groups Small Bore (26 to 50 cm Bore) Medium Bore (60 to 70 cm Bore) Large Bore (80 to 98 cm Bore) < 29 >

30 CBM Cylinder Condition Large bore alternative < 30 >

31 CBM Cylinder Condition Large bore alternative Korea, Autumn 2012, by Henrik Rolsted, LEO MAN Diesel & Turbo 2017 < 31 >

32 CBM Cylinder Condition coating thickness of Cermet < 32 >

33 CBM 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. < 33 >

34 CBM 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. 2.5 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! < 34 >

35 CBM 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 < 35 >

36 CBM Cylinder Condition small bore POP ring. therefore, we have invented Controlled Pressure Relive by means of POP groves (Ports on Plane) < 36 >

37 CBM Cylinder Condition video liner inspection tool Snapshot from a S70ME Video < 37 >

38 CBM Crank train bearings Supporting SL < 38 >

39 CBM Crank train bearings SL Systems that facilitate condition based open-up inspections 1. 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. < 39 >

40 CBM Crank train bearings SL Shaft line earthing devices must be kept working and be equipped with monitoring connected to the alarm system. Bearing inspection schedule Due to the higher safety against major failure, MAN Diesel considers it feasible to completely omit regular open-up inspections of any of the three crank-train bearings featuring an approved BWM system connected to the alarm and slow-down system. For engines comprising an approved MBTM system, regular open-up main bearing inspections can be omitted. 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. < 40 >

41 CBM 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 openup inspections should be carried out according to the findings. < 41 >

42 CBM Crank train bearings XH bearings Normal operation < 42 >

43 CBM Crank train bearings XH Bearings - TC cut out < 43 >

44 CBM 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 < 44 >

45 CBM 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-inoil monitoring system < 45 >

46 CBM 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 days repair < 46 >

47 CBM 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. < 47 >

48 CBM Crank train bearings Main bearings < 48 >

49 CBM Crank train bearings Spark erosion Spark erosion on main bearing journal and in the lower shell Spark erosion on fwd trust collar < 49 >

50 CBM 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 connected to the alarm system, in order to comply. < 50 >

51 CBM 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. < 51 >

52 CBM Crank train bearings main bearing Blend Edge The Blended Edge was introduced as standard in Blended edge can be used as repair solution but only after consulting MAN Copenhagen. < 52 >

53 CBM Crank train bearings Crank pin bearing < 53 >

54 CBM Crank train bearings Why not open? The human factor < 54 >

55 CBM 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 corresponding inspection procedures like regular crankcase inspections required by the engine licenser. The submitted documents will be reviewed by GL experts at the head office. < 55 >

56 CBM 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. < 56 >

57 CBM 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. < 57 >

58 CBM Annual Service Package < 58 >

59 CBM Pre-docking inspections Special Pre-Docking Inspection Alongside by Superintendent Engineer Fuel equipment Cylinder condition Visual inspection of crankcase VAK Measurements Complete Inspection Report Incl. spare part recommendations *Crankshaft deflection is supplied by vessel. < 59 >

60 CBM Pre-docking inspections Upcoming dry-dock (7-9 months) Inspection report Recommended spare parts Spare part offer PrimeServ Copenhagen PO for pre-inspection PrimeServ Copenhagen Pre-Inspection Report & Spare part offer Co-ordination with local Service Centers DD 6 months PO for Spare parts PrimeServ Copenhagen Shipping instructions PrimeServ Copenhagen DD 5 months DD 3-4 weeks Delivery DD 2 weeks < 60 >

61 CBM Pre-docking inspections 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 onsite. < 61 >

62 Surveyor's day Gard/Norwegian Hull Club 2017 Thank you very much for your attention < 62 >