Engine block
The engine block is made of nodular cast iron in one piece for all cylinder numbers.
The engine block has been given a stiff and durable de-sign to absorb internal forces and the engine can there-fore also be resiliently mounted in propulsion systems not requiring any intermediate foundations.
The crankshaft is mounted in the engine block in an un-derslung way.
The main bearing caps, made of nodular cast iron, are fixed from below by two hydraulically tensioned screws.
They are guided sideways by the engine block at the top as well as at the bottom. Hydraulically tensioned hori-zontal side screws support the main bearing caps.
Hydraulic jacks, supported in the oil sump, offer the pos-sibility to lower and lift the main bearing caps for easy maintenance. Lubricating oil is led to the bearings and piston through the same jack. A combined fly-wheel/thrust bearing is located at the driving end of the engine.
The oil sump, a light welded construction, is mounted on the engine block from below and sealed by O-rings. The oil sump is of dry sump type and includes the main dis-tributing pipe for lubricating oil. The sump is drained at both ends to a separate system oil tank. For applications with restricted height a low sump can be specified, how-ever without the hydraulic jacks.
Crankshaft
The crankshaft design is based on a reliability philoso-phy with very low bearing loads. High axial and torsional rigidity is achieved with a moderate bore to stroke ratio.
The crankshaft is forged in one piece. In the V-engines the connecting rods are arranged side-by-side on the same crank in order to obtain a high degree of stand-ardisation between in-line and V-engines. For the same reason the diameters of the crank pins and journals are equal regardless of the engine size.
Counterweights are fitted on every web. High degree of balancing results in an even and thick oil film for all bear-ings.
All crankshafts can be provided with torsional vibration dampers at the free end of the engine, if necessary. Full output can be taken off at either end of the engine.
Connecting rod
The connecting rod is of three-piece design, which makes it possible to pull a piston without touching the big end bearing. Extensive research and development has been made to develop a connecting rod in which the combustion forces are distributed to a maximum area of the big end bearing.
The connecting rod of alloy steel is forged and ma-chined with round sections. The lower end is split hori-zontally to allow removal of piston and connecting rod through the cylinder liner. All connecting rod bolts are hydraulically tightened. The gudgeon pin bearing is of tri-metal type.
Oil is led to the gudgeon pin bearing and piston through a bore in the connecting rod.
Main bearings and big end bearings
The main bearings and the big end bearings are of tri-metal type with steel back, lead bronze lining and a soft and thick running layer.
Cylinder liner
The centrifugal cast cylinder liner is designed with a high and rigid collar, making it resistant against deforma-tions.
A distortion free liner bore in combination with excellent lubrication improves the running conditions for the pis-ton and pispis-ton rings and reduces wear.
Accurate temperature control of the cylinder liner is achieved with optimally located longitudinal cooling bores.
The material composition is based on several years’ ex-perience with a gray-cast iron alloy developed for good wear resistance and high strength.
To eliminate the risk of bore polishing, the liner is equipped with an anti-polishing ring.
The cooling water space between block and liner is sealed off by double O-rings.
4. Description of the engine
Piston
The piston is of composite type, having nodular cast iron skirt and steel top.
The piston skirt and cylinder liner are lubricated by a unique piston skirt lubricating system equipped with lu-bricating nozzles in the piston skirt.
The cooling gallery design assures efficient cooling and high rigidity to the piston top.
Piston rings
The piston ring set consists of two directional compres-sion rings and one spring-loaded conformable oil scraper ring.
Cylinder head
The cylinder head design features high reliability and easy maintenance.
A stiff box/cone like design can cope with high combus-tion pressure.
The basic criterion for the exhaust valve design is cor-rect temperature by carefully controlled cooling.
The cylinder head is designed for easy maintenance with only four hydraulically tightened cylinder head studs.
No valve cages are used, which results in very good flow dynamics in the exhaust gas channel.
Camshaft and valve mechanism
The cams are integrated in the drop forged shaft mate-rial. The bearing journals are made in separate pieces which are fitted to the camshaft pieces by means of flange connections. This solution allows removing of the camshaft pieces sideways. The bearing housings are in-tegrated in the engine block casting. The camshaft bear-ings are installed and removed by means of a hydraulic tool. The camshaft covers, one for each cylinder, seal against the engine block with a closed sealing profile.
The valve mechanism guide block is integrated into the cylinder block. The valve tappet is of the piston type with a self-adjustment of roller against cam to give an even
distribution of the contact pressure. Double valve springs make the valve mechanism dynamically stable.
Camshaft drive
The camshafts are driven by the crankshaft through a gear train. The driving gear is fixed to the crankshaft by means of flange connections.
Injection system
The injection system for each cylinder consists of one injection pump, a high pressure pipe and the injection valve.
The injector is designed to have small areas of the noz-zle tip exposed to the combustion chamber, thus not re-quiring separate nozzle-cooling system.
The injection pump design is a reliable mono-element type designed for injection pressures up to 1500 bar.
The constant pressure relief valve system provides for optimum injection, free from cavitation and secondary injection, which guarantees long intervals between overhauls.
A drained and sealed-off compartment between the pump and the tappet prevents leakage fuel from mixing with lubricating oil.
Each pump is equipped with a pneumatic stop cylinder.
Turbocharging and charge air cooling
The SPEX (Single Pipe Exhaust System) turbocharging system combines the advantages of both pulse and constant pressure system.
In order to optimize the turbocharging system for both high and low load performance a pressure relief valve system “waste gate” is installed on the exhaust gas side. The waste gate is activated at high load. See chap-ter Exhaust gas diagrams.
For cleaning of the turbocharged during operation there is, as standard, a washing device for the compressor and turbine side.
The charge air cooler is as standard of 2-stage type, consisting of HT- and LT-water stage. Fresh water is used for both circuits.
4. Description of the engine
On variable speed engines a by-pass valve is installed to operate the turbocharged at the optimum point at high load and still have enough safety margin against surging at part load. The by-pass arrangement features a pipe with an on/off butterfly valve conducting a part of the charge air directly to the exhaust gas manifold (without passing through the engine) to boost the speed of the turbocharged at part load.
The turbocharged of the in-line engine is installed trans-versely in either end of the engine. Vertical, inclined and horizontal exhaust gas outlets are available.
The turbochargers of the V-engines are installed trans-versely to minimise the required height above the engine by permitting a horizontal, longitudinal exhaust gas out-let. The turbochargers can be located in either end of the engine.
Cooling system
The fresh water cooling system is divided into high tem-perature (HT) and low temtem-perature (LT) cooling system.
The HT-water cools cylinders, cylinder heads and the 1st stage of the charge air cooler.
The LT-water cools the 2nd stage of the charge air cooler, plus the lubricating oil in an external cooler.
Engine driven HT and LT pumps, located in the free end of the engine, are available as options.
Fuel system
The fuel system piping and injection equipment are lo-cated in a hot-box, a proven reliability feature necessary for heavy fuel operation and providing for maximum safety when using preheated fuels.
The injection pump is completely sealed off from the camshaft compartment and provided with a separate drain for leakage oil.
Lubricating oil system
As standard the engine mounted system consists of the by-pass centrifugal filter, and starting-up/running-in fil-ters.
All the other equipment belongs to the external lubricat-ing oil system. The oil sump is of dry sump type.
An engine driven lubricating oil pump, located in the free end of the engine, is available as option.
Exhaust pipes
The exhaust pipes are made of a special nodular cast iron. The connections to the cylinder head are of the clamp ring type. The complete exhaust gas system is enclosed in an insulating box consisting of easily remov-able panels fitted to a resiliently mounted frame.
Direct water injection (DWI), optional
Water is supplied from an external pump unit to a mani-fold in the hot-box, and further via a flow fuse to each in-jector. The injector is equipped with a dual nozzle with separate needles for water and fuel. Excessive water is taken back to an external tank.
An engine with DWI equipment can be operated with or without the DWI system in operation.
4. Description of the engine
Cross section of an in-line engine (1V58F0010)
4. Description of the engine
Cross section of V-engine (1V58F0009a)
4. Description of the engine
Built-on pumps at the free end of the engine (4V58D0091)
4. Description of the engine