Motor ship
A motor vessel is a ship by a motor - driven - usually a diesel engine. The abbreviation MS for motor ship or motor vessel MV for English is often preceded by the ship's name, partly written and M / S or M / V.
Use
Around 1980, large two-stroke engines were the main drive motors for the marine environment; Today there are four-stroke engines. Two -stroke engines with high power are mainly installed in large, fast container ships as a single and double units with a motor and propeller speed of 95-105/min. The medium-speed four-stroke engines ( 350-450/min ) divide, with very few exceptions, the rest This four-stroke engines with up to 13,000 kW are installed, for example, in the Queen Elizabeth 2. For smaller ships four-stroke engines are preferentially incorporated, as these are of considerably lower installation height than the low-speed two-stroke engines. Two -stroke engines are usually slow runner with 94-120/min. Four -stroke engines are medium speed with rotations of 350-450/min or fast runners with rotations of up to 2,300 rpm 2,000 ). Two -stroke engines ( with heights in part from well over 10 meters and up to 2,500 tons of total weight ) are usually installed as single units; Four -stroke engines as single, double, triple, quadruple and multiple systems.
The fuel used in shipping since about 1970 heavy oil. It has a density of up to 0.99 g / cm ³. In order to pump this oil must be preheated to at least 60 ° C. For injection into the engine, the heavy oil is preheated to 130 to 140 ° C. In the inland, however, only gas oil used. Larger marine diesel engines are started with highly compressed air ( 10-35 bar). Therefore, heavy oil -powered diesel engines need several auxiliary equipment and systems such as diesel generators, oil boiler to generate steam to heat the heavy fuel oil tanks, various cooling water pumps, various lubricating oil pump, fuel feed pumps, air compressors and air receiver.
The change of course ( for forward or reverse travel of the vessel ) is done either on the motor itself by pneumatic or hydraulic moving the camshaft, or the engine retains its direction of rotation and the reversal takes place by means of reversing gear. A third variant is the hydraulic or mechanical adjustment of the propeller blades.
Modern passenger ships have now often a diesel-electric propulsion: diesel generators produce electricity and one or more electric motors drive the / propeller.
History
Development
Shortly after its invention of the diesel engine for boats was used soon after for inland waterway vessels. The Danish shipping company Det Østasiatiske Kompagni (East Asiatic Company ) made in 1912 at the shipyard Burmeister & Wain in Copenhagen, the first oceangoing motor vessel, the cargo and passenger ship Selandia build. The 4964 gross tons Selandia measured was 117 feet long, 16 feet wide and had a draft of 9 meters. With two reversible four-stroke diesel engines, the company Burmeister & Wain, each with 920 kW (1250 hp) reached the twin screw ship a speed of 12 knots (22,2 km / h). On her maiden voyage she laid back 22,000 nautical miles ( 40,000 km ).
Through the use of steam in the steam turbine vessels Drive dominated until the end of the Second World War, the seafaring. Also available in larger warships arrived by then the diesel engine is not used; the only exception to this were the three ironclads of the Germany class.
Since the 1950s, dominated in shipbuilding in the motor ships, as they had a higher efficiency, smaller space consumption and lower cost of materials. Only at very high performance requirements nor turbine ships were built up in the 1970s. Beginning of the 21st century, 97 % of all large ships motor boats. The largest marine diesel engines deliver more than 110,000 hp ( 81 MW) in the version with 14 cylinders. The biggest engines come in the 14- cylinder version of MAN B & W ( 14 K 98 MC -C) and Wärtsilä (14 RTflex 96C -B).
Chronology
Environmental characteristics
Motor ships are considered as ecological means of transport; they imply some systemic disadvantages. They have a relatively high efficiency and consume (relative to the transport capacity ) compared by surface modes (rail, truck ), and in particular in comparison with aircraft much less energy.
Marine diesel engines can also run on LPG with diesel fuel, marine diesel oil, heavy fuel oil ( " HFO " ) or for some time.
Especially the relatively cheap Bunker C oil ( heavy oil) has a high sulfur content ( IMO up to 4.5% ); its combustion produces large amounts of sulfur oxides, soot and nitrogen oxides. The petroleum industry uses sea transport as a disposal option for particularly sulfur- containing fuels, which are on land also technological and political reasons can not be used. The event of accidents (eg collisions, sinkings ) of motor vessels can leak fuel into the sea (oil spills ).
By means of new constructions ( common-rail diesel and water injection into the combustion chamber ) is currently trying to reduce emissions. Widespread is already the catalyst technology for the SCR principle ( selective catalytic reduction), which dates from the power plant construction. In it, the exhaust gases are catalytically cleaned by the injection of urea.
By means of emission -related port charges try some port cities to promote the dissemination of clean drives for motor vessels.