Marine diesel engine accessories introduces the difference and role of low speed, medium speed and high speed diesel engines

1, low-speed diesel engines are mostly two-stroke machines, medium-speed diesel engines are mostly four-stroke machines, and high-speed diesel engines have both. The scavenging forms of Marine two-stroke diesel engines include reflux scavenging, direct current scavenging of air port and air port scavenging of opposing piston. High power medium and low speed diesel engines widely use heavy oil as fuel, and high speed diesel engines still use light diesel.

2, the low-speed diesel engine directly drives the propeller, in order to make the propeller have high propulsion efficiency, it requires a low speed. Medium and high-speed diesel engines drive the propeller through the gear reduction box, and the gear box is generally equipped with a reverse car, machine, and structure to achieve propeller reversal, but the low-speed diesel engine and some medium-speed diesel engines can reverse themselves. L28/32 diesel engine accessories, medium and high-speed diesel engines also through the generator - motor - propeller to achieve electric transmission.

Diesel engine has high thermal efficiency, good economy, easy starting, and great adaptability to all kinds of ships, and it was soon used as a ship propulsion power after it came out. By the 1950s, the diesel engine had almost completely replaced the steam engine in newly built ships. Marine diesel engines are already the main power for civil ships, small and medium-sized ships and conventional submarines (see Marine power plant). Marine diesel engine can be divided into main engine and auxiliary engine according to its role in the ship. The main engine is used as the propulsion power of the ship, and the auxiliary engine is used to drive the generator, air compressor or water pump.