WÄRTSILÄ WARTSILA 26, Product Manual

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4. Description of the Engine
4.1 Definitions
Fig 4-1 In-line engine and V-engine definitions (1V93C0029 / 1V93C0028)
4.2 Main engine components
Main dimensions and weights are presented in chapter Main Data and Outputs.
4.2.1 Engine block
The engine block is a one piece nodular cast iron component. The engine block is of stiff and
durable design to absorb internal forces. The engine can be resiliently mounted without requiring
any intermediate foundations.
The engine block carries the under-slung crankshaft.
The main bearing caps, made of nodular cast iron, are fixed from below by two hydraulically
tensioned studs. They are guided sideways by the engine block at the top as well as at the
bottom. Hydraulically tightened horizontal side studs provide a very rigid crankshaft bearing.
For ease of mounting the engine feet (nodular cast iron) can be mounted in a number of
positions along the engine block. This minimises modifications to existing foundation and
makes various mounting configurations easy to implement.
Engine–driven cooling water pumps and a lubricating oil pump are mounted on a multi functional
cast iron housing (pump module) which is fitted at the free end of the engine.
4.2.2 Crankshaft
The crankshaft is forged in one piece and is underslung in the engine block. The crankshaft
design satisfies the requirements of all classification societies.
The crankshaft design features a very short cylinder distance with a maximum bearing length
resulting in a short engine. The crankshaft is forged from one piece of high tensile steel.
Counterweights are fitted on the crankshaft webs. The high degree of balancing results in an
even and thick oil film for all bearings. The gear on the crankshaft is fitted by a flange
connection.
Wärtsilä 26 Product Guide - a9 - 7 September 2016 4-1
4. Description of the Engine Wärtsilä 26 Product Guide