MAN B&W Two-Stroke Service Experience Imabari & Tokyo - November 2014

Transcription

1 MAN B&W Two-Stroke Service Experience Imabari & Tokyo - November 2014 Stig Baungaard Jakobsen Senior Manager Operation Engineering < 1 >

2 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 2 >

3 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 3 >

4 Stay Bolt Failure Investigation, S90ME-C9.2 AVH/LDD1 < 4 >

5 Stay Bolt Failure Investigation, S90ME-C9.2 Background Although broken stay bolts are occasionally seen on engines in service, the frequency of failures is now higher for the S90ME-C9.2 engines than what is usually expected. In addition, the broken stay bolts have been concentrated around the chain drive, suggesting that the root cause is linked to the chain drive for the Hydraulic Power Supply. Measurements From recent measurements carried out on two 11S90ME-C9.2 engines with stay bolt breakage, it was observed that the stay bolts nearest to the chain drive were vibrating resonantly at an engine speed from 57 RPM to 60 RPM. Root cause Stay bolts nearest chain drive are sensitive to vibrations caused by the chain drive at frequencies of 66 th order of crankshaft revolution speed. The excitation is most likely originating from the polygon effect from the 66 teeth module per round of the chain wheels in the chain drive.. AVH/LDD1 < 5 >

6 Stay Bolt Failure Investigation, S90ME-C9.2 Modification to engines already produced: Mounting of additional stay bolt bracing for the stay bolts around chain casing + nearest cylinder fore and aft of the chain drive. Additional bracing Original bracing o o o o o o o o o o o o o o o o o o 7 cyl C/D 12 stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o 8 cyl C/D stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o 9 cyl C/D stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o 10 cyl C/D stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o 11 cyl C/D stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o 12 cyl C/D stay bolts o o o o o o o o o o o o o o o o o o o o o o o o o o o o C/D o Chain drive Extra bracing AVH/LDD1 < 6 >

7 Stay Bolt Failure Investigation, S90ME-C9.2 Four strain gauges: FORE-AFT-MAN-EXH just below the thread on each stay bolt 11S90ME-C9.2 AVH/LDD1 < 7 >

8 Stay Bolt Failure Investigation, S90ME-C9.2 Roll-out of solution for new engines as well as for engines in service is in progress AVH/LDD1 < 8 >

9 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 9 >

10 S90ME-C8/9 & K90ME-C6 Rebuilding to Direct Inlet & LPS Venting Direct Inlet Rebuild Low Pressure Supply (LPS) Main Line Venting Lub Oil Cooler Venting < 10 >

11 Rebuilding Direct inlet Inlet into existing bore Inlet orifice to protect non-return valve New pipe < 11 >

12 Rebuilding Direct inlet, way of flow Ø3 orifice < 12 >

13 LPS Main Line Venting Alternative no. 1 Drain line Drain line going into base plate < 13 >

14 LPS Main Line Venting Alternative no. 2 The drain line from the LPS should be connected to the drain line from the exhaust valve Please connect at the lowest point < 14 >

15 Venting at Lub Oil Cooler Oil inlet Venting line from LO cooler installed directly at T/C LO drain Oil cooler < 15 >

16 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 16 >

17 Increasing Liner Temperature Jacket cooling water Bypass, Basic (JBB) is standard on S60ME-C8.2, S65ME-C8.2 and S70ME-C8.2 JBB can be retrofitted on engines suffering from cold corrosion Jacket cooling water Bypass, Controlled (JBC) is presently developed. JBC can be retrofitted on engines with JBB Load Dependent Cylinder Liner (LDCL) cooling system is standard on Mk 9.2 and later versions of both S and G engine types Early versions of G type engines are only prepared with LDCL pipes not a fully functional LDCL system. A fully functional LDCL system can be retrofitted on these engines Load Dependent High Temperature (LDHT) cooling system is a pre-runner for the LDCL system. Only applied on 5 x (2 x 8S80ME-C9.2) from Doosan New liner design: Rating Dependent Liner (RDL) design New liner design: Hot Replacement Liner (HRL) design SBJ-LEO < 17 >

18 Increasing Liner Temperature JBB or JBC JBB (Jacket cooling water Bypass Basic) JBC (Jacket cooling water Bypass Controlled) Possible upgrade. Being tested not yet available SBJ-LEO < 18 >

19 Load Dependent Cylinder Liner System Overview Cylinder cover outlet Cylinder cover inlet C Two new cooling water main pipes Variable temperature: Up to 130ºC Cylinder liner outlet Cylinder liner inlet Cylinder liner cooling jacket: Ductile Iron (KF) O-rings: Peroxide cured SBJ-LEO < 19 >

20 Load Dependent Cylinder Liner (LDCL) System ~ 85 C ~72 -> ~130 C SBJ-LEO < 20 >

21 LDCL Process 85 C Constant engine load: 85% 76 C Pump not running SBJ-LEO < 21 >

22 LDCL Process 85 C Changing engine load to: 25% 76 C 110 C Pump start running SBJ-LEO < 22 >

23 LDCL Process 85 C At engine load: 25% 110 C Pump running Temperature is given as a table SBJ-LEO < 23 >

24 Load Dependent Cylinder Liner System Water temperature set point ~ 84 C ~72 -> ~130 C SBJ-LEO < 24 >

25 LDCL Integration in ME-ECS < 25 >

26 Increasing Liner Temperature Rating Dependent Liner (RDL) Traditionally cylinder liners are designed for L1 rating MEP (rating) dependent liners can reduce the potential cold corrosion Therefore, it has been decided that three different liner designs will be used for each engine type. The border lines will be based on MEP and are: L1, L1-8%, L1-16%, L4. < 26 >

27 Rating Dependent Liner (RDL) Example: G70ME-C9.5 A new Rating Dependent liner is designed so as the temperature is the same as at high rating. Focus is in the upper part of the liner (first 300mm). L1Liner RDL Liner 30 mm 20 mm shorter Liner position [m] < 27 >

28 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 28 >

29 Cylinder Lubrication Guidelines May 2013 August 2013 November 2013 SBJ-LEO < 29 >

30 Cylinder Lubrication Guidelines Introduced: Feed rate ACC range g/kwh x S% Drip Oil sampling Max Fe values BN values Introduced: Higher ACC factor 0.40 g/kwh x S% BN 70 cylinder oil For Mk 8.2 and 9.2 On board BN shaker Introduced: BN 100 cylinder oil For Mk 8.1 and newer On board DotFast (Fe) May 2013 August 2013 November 2013 SBJ-LEO < 30 >

31 Cylinder Lubrication Guidelines Introduced: Feed rate ACC range g/kwh x S% Drip Oil sampling Max Fe values BN values Introduced: Higher ACC factor 0.40 g/kwh x S% BN 70 cylinder oil For Mk 8.2 and 9.2 On board BN shaker Circular letter only limited distribution Introduced: BN 100 cylinder oil For Mk 8.1 and newer On board DotFast (Fe) May 2013 August 2013 November 2013 SBJ-LEO < 31 >

32 Cylinder Lubrication Guidelines In the beginning of March 2014 Introducing: ACC100 (BN 100) range g/kwh x S% for Mk and newer ACC70 (BN 70) range g/kwh x S% for Mk. 7 and older. SBJ-LEO < 32 >

33 Cylinder Oil Lubrication A minimum of oil is needed to keep the moving parts from seizing. However, the cylinder oil is also used to provide alkalinity (BN) to neutralise the H 2 SO 4 formed during combustion. The oil dosed according to an ACC feed rate factor, which multiplied with the fuel sulphur % gives the feed rate. SBJ-LEO < 33 >

34 Drain Oil Cylinder oil Cylinder oil is injected in the compression stroke, every 1 to 20 revolutions, depending on basic feed rate and engine load. Drain oil The rate of system oil transfer depends on the engine speed and the condition of the stuffing box. SBJ-LEO < 34 >

35 Cylinder Lube Oil Feed Rate Sweep Procedure Purpose Establish the correlation between: Cylinder lube oil feed rate Residual BN in the drain oil Wear particles (Iron, Fe) in the drain oil Lube oil sample 1,6 Sweep Test Drain oil sample 1,4 Feed Rate (g/kwh) 1,2 1 0,8 0,6 0, time (hours) Drain oil SBJ-LEO < 35 >

36 Feed Rate Sweep We estimate that 200 mg/kg Fe will result in a liner wear rate around 0.1 mm/1,000 hr SBJ-LEO < 36 >

37 Service Test Results Fe content in drain oil SBJ-LEO < 37 >

38 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 38 >

39 The Nature of Cold Corrosion Additional Decisive Factor: Water in the Scavenge Air < 39 >

40 The Nature of Cold Corrosion Decisive factors Cold Corrosion depends on: Temperature of liner Pressure on liner Sulphur in the fuel Water amount < 40 >

41 Water in Scavenge Air Free water (droplets) Lub oil break down High wear Liner scuffing Evaporated Water Black liner deposits Higher corrosion potential < 41 >

42 The Nature of Cold Corrosion Water in the Scavenge Air < 42 >

43 Water Mist Catcher Design ~80 % ~15 % ~5 % < 43 >

44 Water Mist Catcher Engine Design The efficiency of MAN Diesel WMC and other designs has been tested on experimental plant < 44 >

45 WMC s Measured in the Test-Rig Test-WMC (MAN Diesel 146º) Test-WMC (Sub-supplier I) Test-WMC (Sub-supplier II) < 45 >

46 Efficiency Versus Air Velocity Majority of WMC mounted has performance similar to sub-supplier II As delivered to MAN spec up till mid 2007 Optimized profile mid 2007 and onwards < 46 >

47 Water Mist Catcher Condition previously often found Broken lamellas < 47 >

48 Water Mist Catcher Condition previously often found No lamellas! < 48 >

49 Water Mist Catcher New design < 49 >

50 The Nature of Cold Corrosion Water in the Scavenge Air 12K98MC in a 5 years period: FW in: Fixed 36 C FW in: SW + 4 C Scavenge air temperature: Air temp after cooler + 3 C Air temp after cooler: FW in + 12 C at 100 % load Tropical condition 100% load: = 51 C Average condition, 100% load: = 39 C Average condition 50% load: = 30 C JWF, LDD < 50 >

51 The Nature of Cold Corrosion Water in the Scavenge Air < 51 >

52 The Nature of Cold Corrosion Water in the Scavenge Air 12K98MC in a 5 years period: JWF, LDD < 52 >

53 The Nature of Cold Corrosion Water in the Scavenge Air Majestic Maersk Sc.air Temp / Humidity Test, Acc 0.25, 66% load, BN100 2 x 8S80ME-C9.2 ppm Fe, CW Temperature, Humidity Scav.air, high humidity Scav.air, low humidity T42 T Tscav ME1 Fe ME2 Fe ME1 Tcwout ME2 Tcwout Humidity ME1 Tsc ME2 Tsc < 53 >

54 The Nature of Cold Corrosion Water in the Scavenge Air < 54 >

55 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 55 >

56 Alpha Mk II New cylinder oil lubricator Alpha Lubricator Alpha Lubricator Mk II Proportional control valve Position sensor SBJ-LEO < 56 >

57 Alpha Mk II New cylinder oil lubricator Test rig Lubricator Injection nozzles Control valve SBJ-LEO < 57 >

58 Alpha Mk II New cylinder oil lubricator The Alpha Mk II can inject cylinder oil with great flexibility: In one or multiple portions per revolution All injections are timed according to the crank angle Multiple injection during each revolution is possible The plunger will deliver oil in the requested portion until full stroke is reached. Then the plunger will return SBJ-LEO < 58 >

59 Lubrication Cylinder lubrication Alpha Mk II Alpha Lubricator Mk I Alpha Lubricator Mk II: A little larger compared to Alpha Mk I 6 mm oil pipes (before 8 mm) Adapter block between HCU and Lubricator. Therefore no changes on the current HCU (the adapter block has the same interface as the current mounted lubriator Mk I) Alpha Lubricator Mk I Alpha Lubricator Mk II SBJ-LEO < 59 >

60 Lubrication Cylinder lubrication Alpha Mk II Service test start: 23 February 2014 SBJ-LEO < 60 >

61 Agenda 1 Staybolt Failures on S90ME-C9 2 Starting Issue for S90ME-C8&9 and K90ME-C6 3 Cylinder Condition Cold Corrosion Control: 4 Increased Cylinder Liner Temperature 5 Improved Cylinder Oil 6 Low Scavenge Air Temperature 7 New Cylinder Lubricators 8 New Cylinder Oils for New SECA <0.1%S Fuels < 61 >

62 Emission Regulations < 62 >

63 Current Agreed ECA s Baltic Sea, North Sea, California, US CARB California Now: 1% sulphur In 2015: 0.1% sulphur < 63 >

64 Cylinder Lube Oil for Ultra Low Sulphur Fuel The challenge Lubrication oil challenge High sulphur fuel low sulphur fuel Deposits on topland, ringland & behind piston rings Risk of bore polish Solution Cylinder lube oil that does not build up deposits < 64 >

65 Low BN Oils for Fuels (< 0.1%S) and Gas Changing from High Sulphur HFO to fuels with less than < 0.1 % S: Switch to a ultra-low BN cylinder oil at the same time as switching fuel Several ultra-low BN oils already have a NOL Chevron: Exxon: Shell : TOTAL : Taro Special HT LF Mobilgard Alexia S3 Talusia LS25 25 BN SAE BN SAE BN SAE BN SAE 50 < 65 >

66 Service Letter Feed rate recommendations New! Engine type Cylinder Oil Feed Rate Service & Circular Letters All ME/ME-C/ME-B/ME/MC/MC-C and ME-GI engines with electronically controlled lubricators bore types MC/MC-C with mechanical lubricator MC-MC-C engines with low topland MC-MC-C engines with high topland and mechanical lubricator. SL /JAP Cylinder Lubrication Update Adjusting the ACC factor in service SL Cylinder Oil Dosage Marine MC-Engines SL Cylinder Lubrication Guidelines Small bore MC/MC-C engines < 66 >

67 Cylinder Oil Choices Engine type 2 stroke engines Engine design Mark 7 Mark 8 Optimised for improved fuel consumption: Part load optimised and derated engines No Yes Base design Cylinder Lube Oil Low S fuel High S fuel 40 BN oil 70 BN oil 40 BN oil BN oil 40 BN oil 100 BN oil < 67 >

68 Cylinder Oil SL cylinder lubrication update Low BN High BN Now even more important because of the new SECA 0.1%S fuel! < 68 >

69 MAN B&W Two-Stroke Service Experience Imabari & Tokyo - November 2014 All data provided on the following slides is for information purposes only, explicitly non-binding and subject to changes without further notice. < 69 >