Tagged: Ship

Engines which connect the world

With the word connection, first thing that comes to everyone is probably the internet itself or fibre optic cables. Well, this one is for the propulsion machinery that makes the real connections possible. Internal Combustion Engines which propel the major share of ocean going carriers across the world’s oceans.

Two stroke, low speed, direct coupled, crosshead type, water cooled, turbocharged, diesel injected, piston cooled, continously rated, reversible engines with external cylinder lubrication. While that might look like a lot of explanation for an engine, there still are a lot more that can be added to differentiate a particular build of these massive prime movers.

While two stroke engines are facing near extinction on land for a variety of reasons, at sea, they are only going from strength to strength and a whole industry is dedicated to take this piece of technology to ensure that producers and consumers stay connected across the continents. Two stroke marine diesel engines propel the major share of world’s commercial vessels. The only competing alternative prime mover for these being turbines and electric motor based flex/pod propulsion.

These engines are not in the league of massproduced car/bike engines churned out at the rates of one piece every 10 minute (or lesser). Each marine diesel is tailored for a specific carrier (ship) right from the ship’s design stage and is assembled inside the hull during ship building. That doesn’t mean that there are standard models available from the producers. There are, but these are built to order and there is no one size suits all on offer.

Though the names suggests that they burn diesel fuel, it may be noted that these engines are built to burn far inferior quality fuel compared to the high speed diesel fuel that cars/truck engines burn. Marine diesels rather use Heavy fuel oil, the heaviest fraction of crude distillation, just above tar. HSD is rarely used to flush these engines prior to a an overhaul or so. A comparison to perceive the amount of power that these machines produce.

  • Peak power output of the 796 cc engine of  India’s best selling hatchback : 48 BHP @ 6000 RPM
  • Peak Power output of  main propulsion engine of the ill fated  of  Exxon Valdez : 31,650 BHP @ 79 RPM. ie; ~ 660 Maruti Alto 800s.

Corporations leading the industry and innovations to existing two stroke marine engines’ technology are Finnish giant Wärtsilä , Swiss corporation Sulzer and Dutch-Danish MAN B&W Diesels. As rightly titled in this video by Wärtsilä, these machines really are The Engines of Industry. Imagine them not working for a few days! No more fun.