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New all-welded engines
with the Götaverken combined uniflow scavenging and constant pressure turbocharging system for the 4,000-30,000 B.H.P. range.
To utilize the advantages of high-pressure turbocharging Götaverken has developed new all-welded diesel engines: DM 52011100, DM 63011400, DM 75011600 and DM 850/1700.
The new types are single-acting, two-stroke, uniflow scavenged engines with constant pressure turbocharging as previous GV types. The components of the new engines have been designed to meet the increased stress induced by high-pressure charging in continuous heavy-duty service. Moreover, several new features have been introduced. An open cofferdam has been placed between the scavenging
air-belt and the crankcase. Here, a double piston-rod scroper box has been installed which can be checked visually without removing any covers.
The connecting-rod-crank ratio has moreover been altered from 4:1 to 3.6:1. Besides giving an engine of reasonable height, this increases the oscillating
angle of the crosshead bearing - which in combination with bearing pin of larger diameter creates better conditions for the formation of an oil film in the benring.
The exhaust-gas manifold has been moved to a position above the turbochargers. By this arrangement, the maximum width of the engine is reduced and
there is now one single-level working platform around the top of the engine.
The standard GV design of cylinder liner, cylinder cover and exhaust valve is retained, together with the characteristic yoke and pull-rods to actuate the
exhaust valve. However, the pullrods are now connected to a fork-shaped lever in the upper part of the crankcase. This lever is actuated by a cam on a separate camshaft. This new arrangement gives better access to main bearings and big-end bearings, and also contributes to quieter operation.
With these new engines the entire output range, from 4,000 to 30,000 B.H.P., is thus weil covered by GV turbocharged diesel engines.
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