The Bedplate is the foundation on which the 2 stroke engine is built. It must be rigid enough to support the weight of the rest of the engine, and maintain the crankshaft, which sits in the bearing housings in the transverse
girders, in alignment. At the same time it must be flexible enough to hog and sag with the foundation plate to which it is attached and which forms part of the ship's structure.Construction
Basically the bedplate consists of two longitudinal girders which run the length of the engine. Connecting these longitudinal girders are the transverse girders which are positioned between each crankshaft throw, and either side of the thrust collar. Built into the transverse girders are the main bearing pockets for the crankshaft to run in.
The bedplate can be made from cast iron as a single casting. Larger engines have a fabricated bedplate i.e., steel sections, steel castings and plates welded together.
Functions
> It is the foundation of the engine gives rigid support to the engine
> It collects crankcase Lube oil to the sump tank.
> Transmit engine load to the ship Structure and distribute these over necessary areas
> Support the dynamic load of running gear of the engine.
> It Support the crankshaft and hold it in perfect alignment
Material
Cast iron
Types of bed plate
.The two types of bedplates in general use are as follows:
> Trestle type.
> Box form or flat-bottomed type.
BOX TYPE/FLAT TYPE Used in Sulzer, MAN B&W