Engine ZA40S Operation SOW.pdf

Wärtsilä Land & Sea Academy

Engine ZA40S Operation and Practical Advanced Course

For Training Purposes Only

Copyright © 2017 Wärtsilä Corporation

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All other products are trademarks or registered trademarks of their respective companies.

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1 © Wärtsilä 27 January 2017 Presentation name / Author

ENGINE ZA40S

Group 0

Wärtsilä Land & Sea Academy

2 © Wärtsilä

Engine description

The Engine ZA40S is a modern in-line and vee form, four stroke engine cylinder bore 400 mm, stroke 560 mm supercharged, inter cooled, medium speed diesel engine.It is a result of continuous development of Z40, ZA40 well proven engines.

High economic efficiency of ZA40S engine is due to a perfect focusing of the following targets:

• High cylinder power trough optimising turbocharger and engine design

•Low specific fuel consumption by optimum selection of T/C system, fuel injection, combustion efficiency and high stroke to bore ratio

•Optimising for further improvements and easy, prolonged overhaul intervals

3 © Wärtsilä 27 January 2017 Presentation name / Author

Engine 16ZA40S

4 © Wärtsilä 27 January 2017 Presentation name / Author

Z-History

• ZH40 type (two-stroke)

– 1965 368 kW/cyl 410 rev/min

• Z40 type (four stroke)

– 1973 440 kW/cyl 500 rev/min

– 1974 480 kW/cyl 530 rev/min

– 1976 533 kW/cyl 530 rev/min

– 1979 550 kW/cyl 560 rev/min

• ZA40 type

– 1983 640 kW/cyl 580 rev/min

• ZA40S type (long-stroke version)

– 1986 660 kW/cyl 510 rev/min

– 1989 720 kW/cyl 510 rev/min

– 750 kW/cyl 514 rev/min

• ZA50S type

– 1995 1200 kW/cyl 450 rev/min

5 © Wärtsilä

Z-family Comparison

Main Differences of Z40/48 to ZA40S Crankshaft embedded in bed plate (crank casing) Cylinder block Pulsation exhaust gas system Speed=500 / 514 / 600 rpm Small fuel pump + reinforced fuel pump for newer engine version Flat cylinder cover without bore cooling Marine head + crankshaft

Main Differences of ZA40 to ZA40S Different stroke, which is the same to Z40/48 Speed=550 / 600 rpm Longer cylinder liner and conrod Crankshaft

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Design Evolution

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Cooling System Development

Z ZAS

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Cylinder Block

Main Bearings Oil Sump Camshaft

ZAV40S

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Main data

10 © Wärtsilä _ZA40S

Main engine dimensions

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Engine ZA40S In-Line

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Engine ZA40S Vee-Form

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Cut-Away View of ZAL40S

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Cut-Away View of ZAV40S

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Numbering of Bearing and Cylinders, Sides

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Numbering of Bearing and Cylinders, Sides

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Crankshaft Rotation & Firing Order counter-clockwise clockwise

DRIVING END

16ZAV40S

CLOCKWISE ROTATION

A1 B1 A4 B4 A7 B7 A6 B6 A8 B8 A5 B5 A2 B2 A3 B3

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Location of Intake and Exhaust Valves

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Flywheel Marks

20 © Wärtsilä Sulzer_ZA40S_V_02_A_Rev00 n Components n01 Lever n02 Hand wheel n03 Electric motor n04 Start blocking valve n05 Flywheel

Volare in alto

Turning of the crankshaft is performed by means of an electrically driven turning device built on the engine.

The turning device consists of an electric motor which drives the turning gear through a gear drive and a worm gear.

Turning device

21 © Wärtsilä

ZAV40S Nomenclature of Major Components

1 Turbocharger 2 Rocker Arms 3 Inlet & Exhaust Valves

4 Cylinder Head 5 Fuel Pressure Valve and High Pressure Fuel Pipe

6 Valve Drive Mechanism

7 Piston 8 Camshaft Bearing 9 Con Rod 10 Engine Housing 11 Covers and Safety Explosion Valves

12 Crankshaft 13 Oil Sump

14 Exhaust Manifold

15 Starting Air Valve

16 Fuel Injection Valve

17 Charge Air Cooler

18 Fuel Injection Pump

19 Regulating Linkage

20 Cams

21 Camshaft

22 Cylinder Liner

23 Main Bearing Cap

22 © Wärtsilä 27 January 2017 Presentation name / Author

Group division

23 © Wärtsilä 27 January 2017 Presentation name / Author

Engine ZA40S

Tools n All tools required for normal engine maintenance are listed on the sheets 9400-1 and following.

n There are also special tools which are only rarely used and which do not form part of the standard tool kit of the engine. These tools can be obtained against a special order.

n A 3rd type of tools are only made available on loan basis. Such tools are identified by a special note in the 2nd column of the tools list.

n Information in the column “Description and Application” indicate for what purpose the tool has to be used.

n Code numbers in the 1st column are the same as tool numbers given in work sheets. When ordering a tool do not omit such a number and for general tools indicate type and size.

n Engine builder reserves the right to alter, remove or add tools and to control what they are used for.

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Hydraulic Tightening

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Tightening Torques

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Tightening Torques

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Estimated Service Life of Components on heavy fuel oil

Componets...................…….....................................................Operating hours

Fuel nozzle.................................................................................................8'000

Inlet valve and valve seat...........................................................24'000 - 36'000

Exhaust valve and valve seat........................................ ............24'000 - 36'000

Piston.........................................................................................48'000 - 60'000

Piston rings..............................................................................................12'000

Oil scraper rings.......................................................................................12'000

Piston ring groove (re-chroming)................................................36'000 - 48'000

Rotating mechanism..................................................................48'000 - 60'000

Top end (spherical) bearing.......................................................48'000 - 60'000

Bottom end bearing...................................................................24'000 - 36'000

Main bearing..............................................................................24'000 - 36'000

Fuel pump plunger and guide bush...........................................24'000 - 36'000

Cylinder liner..............................................................................48'000 - 60'000

28 © Wärtsilä

Summary

1. Z-History

2. Therminology

3. Flywheel Marks

4. Group division

5. Documentation, manuals and tools

6. Tightening Torques

ENGINE ZA40S

Group 1

Wärtsilä Land & Sea Academy

2 © Wärtsilä 27 January 2017 Presentation name / Author

Engine block

Engine block

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Lubricating Oil Flow in Cylinder Block V version

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Oil Supply

Oil to Cylinder

Head

Lubricating Oil Flow in Cylinder Block V version

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ZAV40S

Cylinder block n The Engine housing is of grey cast iron.

n The housing is open at the bottom for fitting the crankshaft.

n The bearing caps are fixed to the engine housing with two vertical main bearing studs each.

nA force fit between engine housing and bearing cap is provided by two transverse tie rods arranged horizontally. In this way the bottom, open part of the housing is given the necessary stiffening.

n The crankcase is accessible through fitting and inspection openings on both sides.

Lubricating Oil Flow in Cylinder Block L version

8 © Wärtsilä 27 January 2017 Presentation name / Author

ZAL40S

Cylinder block n The Engine housing is of grey cast iron.

n The housing is open at the bottom for fitting the crankshaft.

n The bearing caps are fixed to the engine housing with two vertical main bearing studs each.

nA force fit between engine housing and bearing cap is provided by two transverse tie rods arranged horizontally. In this way the bottom, open part of the housing is given the necessary stiffening.

n The crankcase is accessible through fitting and inspection openings on both sides.

ZA40S

Main Bearing Temperature Monitoring, View 1

Lock Nut

Engine Housing

Terminal Box

Clamps

Engine Housing

CableTemperature Sensor

Main Bearing Cover

Temperature Alarms at 92oC

ZA40S

Locating Bearing Temperature Sensor

Locating Bearing Shell

Locating Bearing Shell, lower part

Temperature Sensor

Spring

Union

Main Bearing Temperature Monitoring, View 2 Main Bearing Shell

Temperature Sensor

Main Bearing Cove

Spring

Union

• Depending on installation, alarm or shutdown

• Union threads should be coated with Loctite

12 © Wärtsilä 27 January 2017 Presentation name / Author

ENGINE ZAV40S

Main bearings hydraulic tightening

Tie rods

Main bearing cap

Tools for Loosening and Pre-Tensioning Side & Main Studs

Tools for Loosening and Pre-Tensioning Side & Main Studs

General Procedures in Loosening Transverse Studs

1. Loosen both transverse tie rods simultaneously

2. Loosen both main bearing stud nuts simultaneously

3. Unscrew transverse tie rods

4. Lower bearing cover

Notes:

• Clearance between cylinder and disc must be 2 mm

• Hydraulic pressure is 600 to 620 bar

• 4 to 5 holes spacings

Hydraulic Cylinder On Transverse Studs

Loosening the Crankshaft Main Bearing Stud Nuts

1. Use lifting device 9412.10 to install the pre-tensioning jacks

2. Screw the pistons 7 with a round bar until they land

3. Screw back both pre-tensioning jacks until a gap of 2 mm appears between cylinder 6 and bearing cover 1

4. Build-up a pressure of 600 to 620 bar

5. Unscrew both round nuts by 4 to 5 hole spacings

6. Relieve the hydraulic pressure

7. Remove the pre-tensioning jacks

8. Screw the two round nuts by about 130 to 140 mm downwards

ZA40S

Tools Installation Diagram for Lowering the Main Bearing Cap

1 Bearing Cover

2 Engine Housing

3 Transverse Tie Rods

4 Main Bearing Stud

5 Round Nut

6 Cylinder for hydraulic jack

7 Piston for hydraulic jack

8 Shaft Seal Ring

9 Piston Seal Ring

10 O-ring

11 Disc

12 Round Nut

13 Cylinder for hydraulic jack

14 Shaft Seal Ring

15 Piston Seal Ring

16 Piston for Hydraulic Jack

17 O-Ring

18 Protection Cap

Tools for Lowering the Main Bearing Cover (Cap)

Tools Installation Diagram for Pushing the Main Bearing Cover

Tool Installation Diagram Lowering the Main Bearing Cap

1 Main Bearing Cover

2 Engine Housing

3 Transverse Tie Rods

4 Main Bearing Stud

5 Round Nut

19 Counterweight

20 Upper Shell

21 Lower Shell

22 Crankshaft

23 Oil Sump

Recess for Hydraulic Jack to Lower/Raise Bearing Cap

Working Procedure in Lowering the Main Bearing Cap

Tool for Removing Upper Bearing Shell

Tool Installation Diagram – Removing Upper Bearing Shell

2 Engine Housing

4 Main Bearing Stud

20 Upper Bearing Shell

21 Lower Bearing Shell

23 Oil Sump

ZA40S

Pre-tensioning Main Bearing Stud

1. 600 bar

2. 200 bar

3. Tighten round nuts using tommy bar

4. 40 bar

5. Measure piston protrusion “X”

6. 600 bar

7. Tighten round nuts using tommy bar

8. 40 bar

9. Measure piston protrusion “X1”

The difference between protrusion X and X1 should be 1.2 mm with tolerance of plus and minus 0.1 mm

Pre-tensioning Transverse Tie Rods

1. 100 bar

2. Tighten round nuts using tommy bar

3. 40 bar

4. Measure piston protrusion “X”

5. 600 bar

6. Tighten round nuts using tommy bar

7. 40 bar

8. Measure piston protrusion “X1”

The difference between protrusion X and X1 should be 0.9 mm with tolerance of plus and minus 0.1 mm

ZA40S

General Procedure in Fitting the Main Bearing Cover

1. Press bearing cover upwards and hand fit round nuts

2. Screw-in transverse tie rods

3. Pre-tension both main bearing stud nuts simultaneously

4. Pre tension both transverse tie rods simultaneously

Notes:

• The threads of both the main bearing studs and transverse tie rods should NOT be coated with molykote paste.

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The engine block is a rigid single-piece nodular cast iron design with integrated air receiver and camshaft space. A welded dry or wet oil-sump is fitted below. The crankshaft is underslung. Large openings are provided for inspection and maintenance. The main bearing caps are fixed by hydraulically tightened screws Side covers are fitted with relief valves, opening automatically if the crankshaft space pressure exceeds the acceptable limit.

The cooling water goes to the cylinder liner directly through water space in the engine housing.

Lubricating oil and cooling water are distributed through bored passage ways in the housing n 01 Oil sump

Oil sump

30 © Wärtsilä 27 January 2017 Presentation name / Author

Engine oil sump

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Strainer lube oil filter

Strainer for Oil Outlet

32 © Wärtsilä

The engine block is a rigid single-piece nodular cast iron design with integrated air receiver and camshaft space. A welded dry or wet oil-sump is fitted below. The crankshaft is underslung. Large openings are provided for inspection and maintenance. The main bearing caps are fixed by hydraulically tightened screws Side covers are fitted with relief valves, opening automatically if the crankshaft space pressure exceeds the acceptable limit.

The cooling water goes to the cylinder liner directly through water space in the engine housing.

Lubricating oil and cooling water are distributed through bored passage ways in the housing n A Relief valve “BICERI” n B Relief valve

”HOERBIGER”

A

B

Side covers

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Safety cover n Opens at 0.1 bar n Minimum of 20 minutes cool down

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Photo safety covers

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Bearings

Crankshaft Bearings n The crankshaft bearings are equipped with one each lower and upper bearing shells, which are exactly of the same design and therefore interchangeable.

n On the inner side, the bearing shells are provided with a central groove having several large openings to allow the lube oil to reach the bearings.

n The bearing covers are led transversely into the crankcase. Locking pins prevent the bearing covers from being fitted incorrectly.

n From outwards, the lube oil is routed to each pressure piece via a line connection, and by way of the cavity space of the pressure piece via the thrust bolts to the crankshaft bearings.

n The thrust bolts are tensioned hydraulically.

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The main and thrust bearing shells are bi-metal type aluminium bearings with steel back and AlSn+ lining.

The main bearing shells offer a good sliding surface for the crankshaft journals in the main bearing caps.

n 01 Main bearing shell, upper n 02 Main bearing shell, lower

Main Bearings

37 © Wärtsilä 27 January 2017 Presentation name / Author

Aluminum Coating

Steel Shell n During installation , bearing back should be dry with well lubricated running surface

Main Bearings

Bearing Technology, ZA40S

39 © Wärtsilä n For easy identification of the bearing shell type, their front faces are correspondingly marked (see Fig. 'A'). The last three digits of the marking indicate the running layer of the bearing shell n Crankshaft main bearings as well as connecting rod bottom end bearings with a running layer No. 212 should be used for engines with a nominal output of more than 660 kW per cylinder

Criteria for the Replacement of Bearing Shells

40 © Wärtsilä n Should, in a surface without overlay, 10% of the Al-webs be worn such that their width has increased by more than 75%, then a new bearing shell must be fitted.

n Should the Al-webs on either or both sides of the bearing be fully worn on a width of over 8 mm, then the bearing shell must be replaced.

n Should the overlay be worn out of its grooves on either or both sides by more than 15% of the full running width, then the bearing shell must be replaced.

Wearing of Shells

41 © Wärtsilä n Optimum lubrication of the bearings, prior to starting and while operating the engine.

n Optimum treatment of the lubricating oil by centrifuging n Perfectly working oil filters n Thorough cleaning of the crankcase after overhaul work, and adequately long flushing of the oil piping system.

n Plugging the oil drillings in the crankshaft during overhaul work on the connecting rod bottom end bearing

Care of Bearings

ZA40S

Care of Bearings

1. Optimum lubrication of the bearings, prior to starting and while operating the engine.

2. Optimum treatment of the lubricating oil by centrifuging

3. Perfectly working oil filters

4. Thorough cleaning of the crankcase after overhaul work, and adequately long flushing of the oil piping system.

5. Plugging the oil drillings in the crankshaft during overhaul work on the connecting rod bottom end bearing

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Engine Driven pumps

'Engine driven pumps' are fitted to the engine end cover at the free end and are driven off a gear wheel mounted to the crankshaft. Such pumps are only built on in specific cases and only on non reversible engines. Generally the required pumps are arranged separately in the engine room and are driven by electric motors.

Depending on the requirements, the following pumps can be fitted onto the engine free end.

n 01 Lubricating oil pump n 02 Fuel booster pump n 03 Cylinder cooling water pump (HT) n 04 Raw water pump (LT) n 05 Fuel nozzle cooling water

44 © Wärtsilä 27 January 2017 Presentation name / Author

End cover free end

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Summary

1. Engine housing

2. Main bearing cup

3. Safety covers

4. Oil sump

5. Bearings sheels

6. Engine driven pump

ENGINE ZA40S

Group 2

Wärtsilä Land & Sea Academy

2 © Wärtsilä

Cylinder Liner

Cylinder liner

• The cylinder liner is supported in a suspended manner on the cylinder block. The liner can expands in the downward direction. The upper part of the cylinder is water-cooled. From the cooling water space in the engine casing, the water is routed at an inclined angle to the bores in the annular space of the water guide jacket, which are arranged tangential to the cylinder axis .

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The cylinder liners are made of wear-resistant centrifugal cast iron and are bore-cooled at the upper part to provide a temperature level favourable for good running conditions and low wear rate.

The upper part of the cylinder liner is water cooled. From the coolingwater space in the engine housing the water flows through the tangential bores in the cylinder liner into the cylinder head.

n01 Liner n02 Engine housing n03 O-ring n04 Cooling water space n06 Centering piece for cylinder liner 01

Cylinder liner

Photo of Liner

6 © Wärtsilä

Cut-Away View of Cylinder Liner w/ External Lubrication

7 © Wärtsilä

Cylinder Liner, External Cylinder Lubrication

8 © Wärtsilä

Centering Piece for Cylinder Liner

9 © Wärtsilä

Guide, Lock, Oil Supply to Head

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Photo of Lower O-Ring Groove

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Latest Cylinder Liner with Thread Band

ZA40S

Threaded Band

Coke Deposit

Benefits of Thread Band

Threaded Band • Coke deposit on threaded top ensures gap between the liner running surface and the piston crown

• No contact between piston crown and cylinder liner

• Undisturbed oil film for cylinder liner and piston rings

• No touch marks on the liner through piston tilting

• Reduced wear rates of cylinder liner and piston rings

ZA40S

Ring Ridge

Top Piston Ring

15 © Wärtsilä

Cylinder Liner

Cylinder Liner

Tool for Removing Wear Ridge and Carbon Residue

16 © Wärtsilä

Chris-Marine Honing Machine

Chris-Marine Wear Ridge Milling Machine

Tools for Honing and Milling Wear Ridge

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Maintenance Schedule of Cylinder Liner

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• After a long operating usage, wear ridge appears in the top of the running surface

• If not removed, top piston rings would be broken during piston removal and could cause damage on piston ring land

• Lower the piston, then using wear ridge milling tool, cut the ridge

• The removal of wear ridge should be carried out after the first piston removal.

• Cylinder liner bore must be cleaned very carefully

• On liners with Tread Band, the combustion residue must be removed prior to pulling out the piston. Use the milling tool.

DO NOT REMOVE THE CARBON RESIDUE IN THE TREAD

ITSELF. After removing the residue, the fine thread should measure 400 mm –0.1mm

• If new rings are to be installed, the liner must be honed.

Notes on Liner Maintenance

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Liner Measuring Guide

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• Every 12000 Hr or When the piston is removed

• Maximum clearance due to wear at point A is 1.5 mm and at point B,C, and D is

0.4 mm

• Maximum ovality is 0.5 mm

• Measurement should be done at the same place

• Always measure liners in fitted position and when engine is cooled down

• Avoid measuring errors by preventing the inside micrometer being exposed to heat

Measuring Liner Wear

Example of Liner Measurement

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Tools for Cylinder Liner Maintenance

23 © Wärtsilä

Tools for Cylinder Liner Maintenance

24 © Wärtsilä 27 January 2017 Presentation name / Author

Cylinder liner APR

25 © Wärtsilä 27 January 2017 Presentation name / Author

Anti Polishing Ring

• Polishing effects

Polishing of the cylinder liner takes place when carbon and ash deposits on the piston top land enter in contact with cylinder liner surface

Cylinder liner wear means significant reduction in the lifetime of the cylinder liner, piston and piston ring

• What is needed to avoid Polishing bad effects?

• Carbon deposits on the piston top land have to be calibrated to a thickness small enough to prevent contact between them and the cylinder liner inner wall

Bad lubrication = not stable and increased lube oil consumption

As consequence lubricating oil is lost in deposits

26 © Wärtsilä 27 January 2017 Presentation name / Author

Anti Polishing Ring

ENGINE ZAS

n APR is a centrifugal cast-iron separate ring n it is installed in the upper part of the cylinder liner liner wear significantly reducedcarbon deposits reduced to a small thickness no more contact between deposits and liner wall, at any piston position no oil scraped up-wards by the piston less lube oil consumptio n

Animation of Anti-Polishing Ring

28 © Wärtsilä 27 January 2017 Presentation name / Author

Anti Polishing Ring

• Main Benefits n Wear reduced on:

l cylinder liners, l pistons, l piston rings n Lower and more stable lube oil consumption n Pay - back time in less than 1 year

Very clean piston ring after more than 2000 running hours on HFO

29 © Wärtsilä 27 January 2017 Presentation name / Author n Dismantle of piston, piston crown and cylinder liner n Machining of piston crown and cylinder liner n Reassembling of components by using APR tool n Assemble APR in cylinder liner n No special maintenance action is needed n If in good condition, at 12.000 rh the APR can be turned up-side-down

Operation & Maintenance Simple operations in retrofitting, assembling, substituting:

Anti Polishing Ring

30 © Wärtsilä 27 January 2017 Presentation name / Author

•Possible Packages & Delivery

•Package A:

New cylinder liners and piston crowns modified for APR + new APR n Package B:

Exchange base modified cylinder liners and piston crowns for APR + new

APR

n Package C:

On-site machining of cylinder liners and piston crowns for APR + new APR nDelivery:

work is carried out on site by Wartsila Field Service or in a Wartsila Workshop

Anti Polishing Ring

31 © Wärtsilä

Modified Liner with Anti Polishing Ring

32 © Wärtsilä 27 January 2017 Presentation name / Author

Cylinder Head

ZA40S

Cylinder cover

Every cylinder is equipped with a separate cylinder head that contains:

n two inlet valves with valve rotators and uncooled seats n two Nimonic exhaust valves with valve rotators and water cooled seats n one central fuel injection valve n one starting valve (the no-reversible Vee engine are fitted only on one row of cylinders) n one relief valve n one indicator valve

The cylinder head is cooled by water. The inlet and exhaust valves are different, also their seats are not identical. The valves are marked at the top end of the spindle.The indicator valve screwed into the cylinder head seals off the indicator bore which connects the combustion chamber to the atmosphere. For safety reason a relief valve is fitted to the cylinder head which is set to an opening pressure.

34 © Wärtsilä

The engine is equipped with a separate cylinder head.

The cylinder head is cooled by water, which enters from the bottom via the cylinder liner and flows through various bores (borecooled type). The cooling water leaves the cylinder head through an outlet bore at the top. The inlet and exhaust valves are different, also their seats are not identical. The exhaust seat is cooled by HT water.The valves are marked at the top end of the spindle The indicator valve screwed into the cylinder head is required for measuring the compression and firing pressures during operation For safety reason a relief valve is fitted in to the cylinder head The cylinder head is positioned on the engine housing by a centering pin.

n01 Cylinder head n02 Indicator valve n03 Inlet valve n04 Inlet valve seat n05 Injector valve n06 Pilote starting valve n07 Roker arm

Cylinder head

Cover for Rocker Arm

Tubular Joint

Push Rod

Tubular Joint

Cylinder Head

Connecting Piece

O-Ring

Push Rod Casing

Rocker Arm Casing

Outer Valve Spring

Inner Valve Spring

Thread Protecting Cap

O-Ring

Nut to Cylinder Head Stud

Valve Guide

Inlet Valve, Exhaust Valve

Inlet Valve Seat

O-Ring

Main Rocker Arm Nut for RA Stud

Stud for RA Casing

Hand GripAuxiliary Rocker Arm

O-Ring

Cylinder Head with Cover

36 © Wärtsilä 27 January 2017 Presentation name / Author

Main Rocker Arm Auxiliary Rocker Arm

Shaft for Main Rocker Arm

Ball Head Cups

Cylinder Head

Rocker Arm Casing

Rocker arms actuates the inlet and exhaust valves of every cylinder

Rocker Arms

Rocker Arms Assembly

38 © Wärtsilä 27 January 2017 Presentation name / Author

Rocker Arms Assembly

Valve Adjustment Procedure

1. Loosen lock nuts 4 and 7 and turn 3 and 6 ccw

2. Push feeler gauge fully between the ball socket 5 and the valve spindle 1 or 2 respectively

3. Tighten screw 3 lightly with allen key until feeler gauge is slightly gripped, but can still be moved by pulling

4. Leave the feeler gauge clamped in this way, hold screw 3 with the allen key and tighten at the same time the lock nut 4 firmly

5. Leave the feeler gauge clamped in valve 1. Push the feeler second feeler gauge under the ball socket 8 and 2

6. Tighten screw until the feeler gauge is gripped slightly

7. Hold screw 6 with allen key and tighten lock nut 7

40 © Wärtsilä 27 January 2017 Presentation name / Author

Fuel Pressure Valve

High Pressure Fuel Pipe

Fuel Stud Nozzle Holder

Nut for Fuel Injector Flange for Fuel Injector Nut for SA Valve

Flange for SA Valve

Starting Air Valve

Fuel Injection Nozzle Insert BushSoft Iron GasketCylinder Liner

IO-Ring Connecting Nipple for Indicator Valve

Indicator Valve

Fuel Leakage Pipe

IO-Ring

Cylinder Head

41 © Wärtsilä 27 January 2017 Presentation name / Author

Pictorial View of Cylinder Head

Intake Valves

Cylinder Head Studs

Air Starting Valve

InjectorOperating Side

42 © Wärtsilä 27 January 2017 Presentation name / Author

Cylinder cover

43 © Wärtsilä 27 January 2017 Presentation name / Author

Valve Guides

44 © Wärtsilä 27 January 2017 Presentation name / Author

1 Rocker Arm 2 Shaft for Main RA 3 Cylinder Head 4 Oil Connection

Piece 5 Oil Connection 6 Screws 7 Flange 8 Centring Pin 9 Engine Housing 10 O-Ring 11 Fuel Injector Valve 12 Starting Air Valve 13 Relief Valve

OE Oil Inlet EXV Exhaust Valve ILV Inlet Valve

Cylinder Head, Top View

45 © Wärtsilä 27 January 2017 Presentation name / Author

Push Rods

Push Rods

47 © Wärtsilä 27 January 2017 Presentation name / Author

Lube Oil Air Vent

Lube Oil Air Vent

48 © Wärtsilä 27 January 2017 Presentation name / Author

Indicator valve

Indicator valve ZAS

In addition to this, an indicator cock 16 is fitted in the lower part of each cylinder head and is connected through the combustion chamber.

Depending on the order, these may be supplied by KIENE or

SCHNEIDER.

49 © Wärtsilä

The relief valve in every cylinder head safeguards the cylinder against Inadmissibly hight pressure.

The opening pressure is adjasted by the hight of the distance ring.

The opening pressure depends on the engine rating and is stamped-in on top of the valve housing.

To vary the opening pressure by about 1 bar, the ring height has to be modified by about 0,1 mm n01 Cylinder head n02 Distance ring n03 Spring n04 Valve seat n05 Ball

Relief valve

50 © Wärtsilä

Fuel injector valve The fuel injection valve, called injector for short, is water cooled.

It is pressed onto its seat in the cylinder head by a pre-tensioned spring washer stack. Sealing to the combustion space is metallic, i.e. it is not permitted to use a joint.

With the aid of the spring tensioner, the prescribed opening pressure (spraying pressure) can be adjusted.

Regarding opening pressure, refer to the resp. setting table delivered with the engine documentation.

The nozzle body and its needle form one unit, therefore it must be strictly avoided to interchange the single parts. They are always supplied as one unit.

n A Fuel in n B Leak fuel n 01 Holder body n 02 Nozzle body n 03 Nozzle needle n 04 Spindle n 05 Spring n 06 Adjusting screw n 07 O-ring n 08 Lock nut n 09 Nozzle nut n 10 Spring washer stack

06 08

A

51 © Wärtsilä

Fuel injector valve

The fuel injection valve, called injector for short, is water cooled.

n A Cooling water in n B Cooling water out

A B

A

B

Water Cooling Lines for Injector

Checking the Condition of Injector

Spray Pattern Test - loosen lock nut 2 and spring tensioner 1, to relieve the nozzle needle of tension. Check by few short pump strokes whether the fuel is equally distributed from all spray holes.

Valve Opening Pressure Test - using spring tensioner 1, adjust the opening pressure of the fuel injection valve to 400 +-10bar or according the setting table.

Needle Seat Leakage Test - apply a pressure of 200 bar over a period of 5 seconds and observe the needle tip for droplets.

Estimated life of fuel nozzle is 8000 operating hours

54 © Wärtsilä

Two inlet valve with valve rotators and uncooled seat ring.For both power ranges the inlet valve is provided with a ROTOCAP rotating device. It produces a rotating movement.

The valve seat angle is 30°.

Material is Stellite12.

Valve rotators ROTOCAP type n01 Inlet valve n02 Valve seat n03 Spring n04 Rotocap n05 Conical clamping half-ring n06 Valve guide

30°

+2

20 – 80 %

0,005-0,015 mm

Inlet valve

55 © Wärtsilä 27 January 2017 Presentation name / Author

• Forced rotation for even temperature distribution and to keep the sealing surfaces free from deposits

• The rotocap rotates the intake valve when it opens.

• 24000 to 36000 Expected Life Cycle

Intake Valve with Rotocap

56 © Wärtsilä 27 January 2017 Presentation name / Author rotocap

57 © Wärtsilä

Two Nimonic exhaust valves with rotators and water-cooled seat ring Valve rotator TURNOMAT type

Exhaust valve seat for ZA40S engine with MCR = 720 KW / Cyl Or Ratings ER I / ER II = 660 / 600 KW / Cyl n01 Inlet valve n02 Valve seat n03 Spring n04 Turnomat n05 Conical clamping half-ring n06 Valve guide

0650 – 100 % 45°+2

Exhaust valve

58 © Wärtsilä 27 January 2017 Presentation name / Author

Exhaust Valve with Turnomat

• Forced rotation for even temperature distribution and to keep the sealing surfaces free from deposits

• The nimonic exhaust valves are equipped with an efficient TURNOMAT valve rotating system.

• Rotates partially when closed

• Exhaust valve rotates at closing – giving a clear advantage of a seat cleaning effect to reduce the formation of deposits on the valve seat

59 © Wärtsilä 27 January 2017 Presentation name / Author turnomat

60 © Wärtsilä 27 January 2017 Presentation name / Author

Exhaust Valves

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Real Photo of Cylinder Head, Bottom View

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Freezing Intake Valve Seats in Liquid Nitrogene

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Y = 11.8 -0.3 +0.4 mm X = 27 -0.1 +0.2 mm

Extracting the Exhaust Seat Bush

Verifying Seat Distance of Exhaust Seat

Electric Arc Welding Seam

Pusher Plate

Cool down the bush to -190oC before installation Use Loctite 648

Preferably install the valve seat after 12 hours after installing the bush

Exhaust Valve Seat and Bush

Apply a thin amount of mechanic blue around the periphery of the intake and exhaust valves.

With the head upside down, push the the spindle against the valve seat. Do not rotate the spindle.

Intake seat angle is 30o +2

Exhaust seat angle 45o +2

Bluing test

Removing valve guide Installing valve guide

Removing and Installing Valve Guide

• Lapping-in of the valve with the valve seat using grinding paste is strictly forbidden

• Avoid grinding near vibrating machinery

• Apply dye penetration to check for cracks after grinding

• When do you do valve seat grinding:

- every time new valve seat have been fitted in the cylinder head

- when new or reconditioned valve spindles are being fitted (only when not corroded nor pitted.

- when the seat surface of the exhaust valve seats is badly impaired

• Intake valve seat angle is 30o +2’

• Exhaust valve seat angle is 45o +2’

Notes on Valve Spindles and Seats

67 © Wärtsilä

Fuel pressure valve and high pressure fuel pipe

Each fuel stud is equipped with a pressure valve, which ensures that during operation the fuel pressure before the fuel injection nozzle is maintained as high as possible. This prevents to a great extent cavitation erosion in the fuel injection valve.

Possible leakages between the delivery valve and the fuel stud or between delivery valve and high pressure fuel pipe are collected and led inside the protection pipe via the fuel injection pump cover into the fuel leakage collecting pipe.

The protection pipe around the high pressure fuel pipe is designed to prevent fire hazard in case of a bursting fuel pipe. As the high pressure pipe and protection pipe form a unit they can only be replaced together.

68 © Wärtsilä 27 January 2017 Presentation name / Author

Fuel delivery valve and pipe type 714 M27

Fuel delivery valve and pipe type 714 M27

70 © Wärtsilä 27 January 2017 Presentation name / Author

Fuel delivery valve and pipe type 808 M39

71 © Wärtsilä

Fuel pressure valve and high pressure pipe 723 M39 SOLAS n 01 Fuel injection pump cover n 02 Delivery valve n 03 Double wall pipe n 04 Leakage fuel n 05 Connection pipe

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Solas requirements

High pressure fuel pipes ”All external high-pressure fuel delivery lines between the high-pressure fuel pumps and fuel injectors shall be protected with a jacketed piping system capable of containing fuel from a high-pressure line failure. A jacketed pipe incorporates an outer pipe into which the high-pressure fuel pipe is placed, forming a permanent assembly. The jacketed piping system shall include a means for collection of leakages and arrangements shall be provided for an alarm to be given of a fuel line failure.”

Hot surfaces ”All surfaces with temperatures above 220 °C which may be impinged as a result of a fuel system failure shall be properly insulated.”

Low pressure fuel oil pipes ”Oil fuel lines shall be screened or otherwise suitably protected to avoid, as far as praticable, oil spray or oil leakages onto hot surfaces, into machinery air intake, or other sources of ignition. The number of joints in such piping system shall be kept to a minimum.”

Lubricating oil arrangements ”The arrangements for the storage, distribution and utilization of oil used in pressure lubrication systems shall be such as to ensure the safety of the ship and persons on board. The arrangements made in machinery spaces of category A, and whenever practicable in other machinery spaces, shall at least comply with the provisions of paragraphs 2.1, 2.4, 2.5, 2.6, 2.7, 2.8, 2.10 and 2.11 ”screened or otherwise suitably protected”.

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Starting air valve

A starting air valve is fitted in each cylinder head and is controlled by control air from the starting air distributor It admits starting air (30 bar) to the cylinders in certain positions of the piston.

n Components n 01 Valve casing n 02 Valve spindle n 03 Working piston n 04 Control valve n 05 Valve guide casing n 06 Spring n 07 Spring washer stack n Connections n A Starting air n B Control air

A

B

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Starting air valve n Components n 01 Valve casing n 02 Valve spindle n 03 Working piston n 04 Control valve n 05 Valve guide casing n 06 Spring n 07 Spring washer stack n Connections n A Starting air n B Control air

A

B

A

03 02

75 © Wärtsilä

Starting air valve n Components n 01 Valve casing n 02 Valve spindle n 03 Working piston n 04 Control valve n 05 Valve guide casing n 06 Spring n 07 Spring washer stack n Connections n A Starting air n B Control air

A

B

76 © Wärtsilä

Starting air valve n Components n 01 Valve casing n 02 Valve spindle n 03 Working piston n 04 Control valve n 05 Valve guide casing n 06 Spring n 07 Spring washer stack n Connections n A Starting air n B Control air

A

B

77 © Wärtsilä 27 January 2017 Presentation name / Author

Starting air valve and dummy valve

78 © Wärtsilä 27 January 2017 Presentation name / Author

Air Starting Valve at the Rear Side

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“B” Bank

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Exhaust Port and Intake Manifold

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Dummy Air Starting Valve at Operating Side

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Maintenance Schedule of Cylinder Head

Tools for Cylinder Head a

Drain cooling water to maintenance tank device 9427.34 Loosen nuts 1 of cowling in even steps

Remove cowling 2 with the help of lifting device 9427.34

Removing Cylinder Head -Work Flow

Tool for Removing Valve Cowling

Remove both push rods and screws 14

Remove high pressure fuel pipe 18. Cover all openings with suitable materials

Fit jacks on each of the 8 cylinder head studs Screw in the jack till point “B” is reached Rotate cylinder anti clockwise to produce 2 mm gap in “S” Unscrew all the nuts by 4 to 5 hole spaces

Removing Cylinder Head -Work Flow

Tightening jack using 9431.03 tool

Using 9427.09 jack screws for jacking up the cylinder head off the cylinder liner

Lifting cylinder inclinde

Removing Cylinder Head -Work Flow

90 © Wärtsilä 27 January 2017 Presentation name / Author

Threaded Hole for Pulling Cylinder Head out of Liner

Removing and Installing the Injector Insert Bush

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Pressure test when all inserts are installed. Do it twice, before and after overhaul Fill water until air escapes from vent 6.

Apply a pressure of 7 bar for minimum of 15 minutes.

Cylinder Head Pressure Test

93 © Wärtsilä 27 January 2017 Presentation name / Author

• Inspection of cooling water spaces

• Surfaces in contact with combustion must be inspected for cracks

• Water pressure test must be conducted when (a) crack is suspected, and (b) replacement of valve seats and insert bushes

• Water pressure test of cylinder head at 7 bar

• O-Rings of valve guide bushes must be replaced

• Lapping of contact surface with cylinder liner

• Lapping of injector insert bush

• Valve seats with water leakage must be replaced

• Damaged seat surfaces must be reconditioned

Always put the cylinder in question at TDC before loosening the cylinder head nuts

Notes When Overhauling Cylinder Heads

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Summary

1. Cylinder liner

2. Cylinder liner tools

3. Anti polishing ring

4. Cylinder cover

5. Rocker arm

6. Push rods

7. Safety valve

8. Indicator valve

9. Fuel injection

10. Valves inlet\exhaust

11. Rotator mechanism

12. High fuel pressure pipes

13. Solas requirement

14. Starting air valve

15. Tools

ENGINE ZA40S

Group 3

Wärtsilä Land & Sea Academy

2 © Wärtsilä 27 January 2017 Presentation name / Author

Crankshaft ZA40S

Crankshaft is under slung. One piece construction, fitted with counterweights, gear wheels for camshaft drive and built-on pumps in certain cases. Contains vibration damper at the free end side.

Pictorial View of Crankshaft

• Shaft journals and crankpin are drilled through, so that lube oil brought to the main bearings also lubricates the crankpin bearings

• To counteract unbalanced forces counterweights are fitted to the crank webs

• By measuring crankshaft deflection, the correct level of the main bearing can be checked

4 © Wärtsilä

The crankshaft is forged in one piece from alloy steel and machined all over. The balance weights are bolted onto the crankshasft to obtain favourable bearing loads and vibration-free running. Drillings in the crankshaft feed the lubricating and cooling oil, which enters at the main bearings and passes through the connecting rod and spherical bearing, into the piston crown.

The rigid design of the crankshaft allows an optimum economic choice of the vibration damper, which is normally fitted at the free end of the shaft where auxiliary drives can also be accomodated.

The flywheel and the turning gear are located at the driving end of the crankshaft. The main bearing next to the flywheel is flanged in the engine housing.

n 01 Crankshaft n 02 Camshaft driving gear wheel n 03 Counterweight n 04 Thrust bearing shaft n 05 Screw for counterweight

02 03

Crankshaft

Longitudinal View of Crankshaft

7 Shaft Extension for crankshaft 8 Fitted Coupling Bolts 9 Gear Wheel on Crankshaft 10 Oil Connecting Sleeves 11 O-Ring M Marking

ZA40S

Nomenclature of Crankshaft

1 Crankshaft 2 Positioning Pin 3 Tension Stud 4 Counterweight 5 Round Nut to tension stud 6 Threaded Plugs

Every Year - check waisted studs for correct pre-tensioning and retighten if necessary

Counter Weights

8 © Wärtsilä 27 January 2017 Presentation name / Author

Crankshaft ZA40S V-L version

Measuring Crankshaft Deflection, Dial Indicator

Measuring Crankshaft Indicator, Digital Instrument

When to Conduct Crankshaft Deflection Check

Limit Values of Crankshaft Deflection

13 © Wärtsilä Sulzer_ZA40S_V_02_A_Rev00

The thrust bearing is next to the flywheel is flanged in the engine housing.

n 01 Thrust bearing n 02 Camshaft driving gear wheel n 03 Crankshaft n 04 Thrust bearing shaft n 05 Engine end plate

Crankshaft thrust bearing

Photo of Thrust Bearing Assembly

Thrust Bearing

• Upper and Lower Bearing are Identical with oil grove

• Oversize thrust ring, if re-machined the shaft collar

ZA40S

Thrust Bearing, Front and Top Cross Sectional Views

Clearance between shaft and oil catcher should be about 1 mm all around.

The rigid design of the crankshaft allows an optimum economic choice of the vibration damper, which is normally fitted at the free end of the shaft where auxiliary drives can also be accomodated.

n 01 Vibration damper n 02 Pump driven gear wheel on crankshaft n 03 End cover on free end n 04 Flange cover on free end 01 02

Vibration damper

How Torsional Vibration Occurs

Nomenclature of Fluid Vibration Damper

1 Housing 2 Damping Mass 3 Bearing 4 Damper Oil (Silicone) 5 Closing Plug for when taking samples M Marking

• No outside lubrication

• Torque is transmitted to the damping mass by the friction of the silicon oil.

• There is relative motion bet housing and mass

• Friction in silicon oil bring the damping of torsional vibration

• Do not paint the housing

ZA40S

Taking Silicone Fluid Samples From The Viscous Torsional Vibration Damper Sample first on 12,000 hrs to establish schedule. Isolate The Engine !

1 3 4 52 Remove free end inspection cover.

Rotate engine until one plug is visible, wait 1hr. Sample container has two threads. Remove cap nut with thread to match filling plug

Remove filling plug and screw container into filling hole.

Remove the other cap nut.

Allow fluid to reach open end of container. May take 60 sec or 1hour dependant on conditions.

Replace cap nut and unscrew container.

Immediately fit new damper plug.

Torque to 2.5kg/m (18ft/lbs). Lock by punching cover material into plug slot.

Fit second cap nut to container .

Ensure container is at least 75% full.

Fluid Vibration Damper

Sampling Silicon from Viscous Vibration Damper

ZA40S

Notes on Sampling

• Take sample at the first 12000 operating hours to establish the interval

• Secure from the manufacturer the sample containers

• Cool down vibration damper to about room temperature

• Total number of samples is limited to 10

• Label should contain Engine Type, Engine No. and operating hours

Geislinger Leaf Spring Damper, Inspection Every 30000 h

1 Oil supply hole 2 Damper Inner Part 3 Damper Outer Part 4 Spring Pack (Leaf Spring) 5 Closing Cover 6 O-ring 7 O-Ring M Marking

• Requires oil from the engine for lubricating and cooling

• Torque is transmitted to the damper outer part by the flexible leaf spring pack

• Relative motion inner part and outer part

• Oil is forced from one chamber to another through restricting slits thus damping vibration

24 © Wärtsilä 27 January 2017 Presentation name / Author

Connecting rod

The connecting rod have a central bore to feed lubricating oil to the spherical bearing and cooling oil to the piston crown.

The short connecting rod shaft with spherical head is connected to the big end by four hydraulically tightened studs. The big end of the connecting rod is assembled with four hydraulically tightened studs.

The compression shims are fitted by the engine manufacturer in accordance with the cylinder power capacity.

n01 Connecting rod n02 Nut n03 Stud to crankpin bearing n04 Lower bearing shell n05 Upper bearing shell n06 Crankpin bearing body (lower half) n07 Crankpin bearing body (upper half) n08 Compression shim

Connecting rod

26 © Wärtsilä 27 January 2017 Presentation name / Author

ZA40S

Connecting rod n The piston bearing is situated on the Upper spherical end of the connecting rod.

n An upper and lower bearing half is fitted to the crank pin bearing, which are of different design.

n The lubricating oil is fed through a drilling from the main journal to the crank pin and part of it flows through a central bore in the connecting rod to the piston bearing.

n The connecting rod head as well as the two bearing halves are bolted together with rolled studs, which are hydraulically pre-tensioned.

n The compression shims 9 are fitted by the engine manufacturer in accordance with the cylinder power capacity and require no modifications for normal operation. The corresponding shim thickness is recorded in the setting table.

• Piston bearing is situated on the upper spherical end of the con rod

• Upper and lower bearing shell are different and therefore should not be interchanged loc.

• Drilled bore along the length of con rod

• Compression shim thickness is recorded in the setting table

General Notes About Piston and Con Rod

28 © Wärtsilä 27 January 2017 Presentation name / Author

ZA40S

Piston conrod

Upper half bearing cap

Lower half bearing cap

Connecting rod

Connecting Rod ZAS

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Inside Photo of Con Ron On Engine

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24000 to 36000 h Expected Life

Con Rod Bearing Shells

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Piston and Con Rod

Power Upgrade

Operation n The upgrade action is suggested to be carried out during a major overhaul n Main engine parts interested in the upgrade:

- Exhaust and Inlet valve assembly

- Fuel injection nozzle

- High pressure fuel pipe

- Crankshaft (material specification Rm=800N/mm2 as minimum value)

- Torsional vibration damper (new TVC must be evaluated)

- Rotating piston assembly

- Camshaft vibration damper

- Fuel pump plunger / cylinder, fuel pump cover

- Fuel pump setting

- Turbo Charger assembly

- Charge Air Cooler assembly

- Cylinder Lubrication system

- Waste Gate valve

Solution extensively tested

34 © Wärtsilä

Piston

ENGINE ZA40S

• Rotating Piston

• Service experience

Ä In 50 years of application, on test bed and in service, the rotating piston has demonstrated that piston running behaviour need not to be a sensitive issue in diesel engine design.

Ä It has given the Z-type medium-speed engines a unique advantage in coping with poor-quality fuel oils and extreme operating conditions, such as rapid changes in engine load, while maintaining stable, low lubricating oil consumption.

Ä A significant number of Z-type engines are serving in icebreakers with continual and extreme load fluctuations, in ferries on intensive short-sea services and in rapid start- standby generating plant for nuclear power station.

36 © Wärtsilä

Dismantle piston every 24000 hours

Rotating Piston

Pictorial View of Piston and Connecting Rod

38 © Wärtsilä 27 January 2017 Presentation name / Author

Z40

• Rotating Piston

• Full rotational symmetry

– Piston design due to spherical bearing has full rotational symmetry.

– Gas forces are transmitted centrally without loading the piston skirt.

– Deformations are totally symmetrical and piston maintains its cylindrical form without ovality.

– Temperatures are also equalised around the piston so that thermal loads are again symmetrically distributed.

– At an engine speed of 510 rev/min the piston rotates at about 9 rev/min.

39 © Wärtsilä 27 January 2017 Presentation name / Author

Z40

•Rotating Piston •Behaviour

– A distinctive feature since its introduction in the early 60s with Z-types production and continued application in the latest ZA40 and ZA40S.

– The tangible benefits to the engine users, in contrast with usual gudgeon pin-type piston, can be summarised:

– Dependable safety

– Long lube oil consumption over the all engine life

– Low wear rates for piston rings cylinder liners

– Far less liability to scuffing and seizure

– piston overhaul intervals

– Stable, low Long piston life

40 © Wärtsilä

Operating Principle of Rotating Piston

41 © Wärtsilä

Steel Crown

Pictorial View of a Cut-Away Rotating Piston

42 © Wärtsilä 27 January 2017 Presentation name / Author

Z40

• Rotating Piston

• Drive principle

• A pawl-and-ratchet mechanism transforms the swinging motion of the connecting rod trough a damping spring into a smooth, steady rotation of the piston.

• At an engine speed of 510 rev/min the piston rotates at about 9 rev/min.

Inside View of Rotating Mechanism

44 © Wärtsilä

Ratchet Ring

Animation of Rotating Piston

45 © Wärtsilä

Ratchet

46 © Wärtsilä

Ring Spring

Toothed Rim

Guide Bush

Toothed Rim, Ring Spring, Guide Bush

47 © Wärtsilä

The profiled first piston ring has a chrome-ceramic running layer and chromium plated flanks whereas the second…