Promoting Democracy in Algeria

Maritime Speed

Tension transients in the fact that in the process of regime change (load and speed) are abrupt changes in the workflow, changing the conditions of heating and cooling the cylinders and pistons. Stresses occurring in the engine parts cpg and crank, growing at an increasing speed of regime change and become the greatest when starting a cold engine, sharp deriving its full load and a sudden stop with full speed. In these circumstances, elements of design are the strain and wear intensity change of clearance and tightness in the pairing. In detail, experience the action of high temperatures, developing termoustalostnye phenomena over time, leading to the formation of cracks. When starting a cold engine in the cylinders created adverse conditions for ignition of fuel. Combustion it is accompanied by the excessive high pressure and high speed of its growth. This leads to an increase in stress in detail cpg and crank, a large shock loads in the bearings.

High-pressure combustion pz arise when starting up warmed-up engine, if it is not enough spins in the air, and to create a needed boost given large fuel supply. Thus, when the automatic engine start Sulzer type RD16 on the maximum program providing for withdrawal of the engine immediately after starting at full speed. Such stringent conditions and start the motor up to full speed should be allowed only in exceptional (emergency) situations. In normal conditions trigger the fuel rail should be installed in the position of small innings and the motor should be implemented gradually. Rate of increase in the fuel cycle chosen so as to ensure a sufficiently low the rate of temperature rise of parts cpg. Tough job engine at start-up can also occur when you use heavy fuels, which are characterized by poorer atomization, evaporation and slow combustion.

Therefore, recommended to start the engine on diesel fuel. Reliable self-ignition of fuel in the cylinder is determined by the temperature of compressed air. The latter depends on the ambient temperature, the thermal state engine, piston rings and the state starting speed (average speed of the piston). Therefore, to ensure easy start, the engine must be preheated, pumping hot water through it, to be selected usually from the cooling system of auxiliary diesel engines. On heating, reducing wear of cylinders in the starting period, as well as reduced corrosive action of acids formed during combustion. Reducing heat loss in cylinder wall contributes to the temperature and pressure at the end of compression and reduce the induction period, in connection with what is largely reduced pressure arising in the cylinder when the first outbreak. This eliminates the mechanical electrical parts of the cylinder and improves the crankshaft bearings. When operating a cold engine lubrication of bearings and other friction units is insufficient, because the oil does not have time to warm up, and high viscosity makes it difficult to move. Big oil viscosity causes an increase in resistance to spinning the engine start-up period. In this connection it is necessary to warm up before starting the engine lubricating oil, located in the circulation tank or sump, to a temperature of 40-45 C. Source: Maritime companies

Comments are closed.