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Showing posts from January 16, 2010

Lubrication System Diesel Engines

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An internal combustion engine would not run for even a few minutes if the moving parts were allowed to make metal-to-metal contact. The heat generated due to the tremendous amounts of friction would melt the metals, leading to the destruction of the engine. To prevent this, all moving parts ride on a thin film of oil that is pumped between all the moving parts of the engine.Once between the moving parts, the oil serves two purposes. One purpose is to lubricate the bearing surfaces. The other purpose is to cool the bearings by absorbing the friction generated heat. The flow of oil to the moving parts is accomplished by the engine's internal lubricating system.Oil is accumulated and stored in the engine's oil pan where one or more oil pumps take a suction and pump the oil through one or more oil filters as shown in Figure 12. The filters clean the oil and remove any metal that the oil has picked up due to wear. The cleaned oil then flows up into the engine's oil galleries. A…

Pistons & Rings

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Premium quality pressure die cast Aluminum Pistons and Cast as well as forged rings manufactured under stringent supervision. In house production of Centrifugally cast Ni resistant Rings. Material Standard LM 13 for Pistons and S G Iron and stainless steel Rings Material analysis, Pressure test, Tensile and Fatigue tests, Hardness, Thermal shock and expansion and profile tests are carried out for pistons and Rings. Piston Pins are manufactured with 20 Mn Cr5 material with hardening process to achieve the case hardness of 52-58 Hrc Wide Range available and development capacity of any Pistons and Rings upon samples. Capacity of supplying 25000 pistons and Ring sets per month

Diesel Engine Cylinder Liner

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Diesel Engine Cylinder Liner1. Function of cylinder liner
1) Formed cylinder working space with cylinder cover and piston.
2) Cylinder liner of trunk piston diesel withstands side thrust of piston, so it becomes lead of piston reciprocating action.
3) Transmit heat of piston assembly and self-heat to cooling water to keep its proper working temperature.
4) Cylinder liner of two stoke diesel engine is equipped with vent; it is hoisted by piston to achieve air distribution.
2. Working condition
Inside cylinder liner is directly affected by high-temperature and high-pressure gas, and always produce high-speed slide friction with piston rings and piston skirts. While its outer touch with cooling water, producing serious thermal stress under big difference in temperature and corroded by cooling water. Side thrust from piston not only acerbates inside friction of cylinder liner, but also makes it bent. When side thrust changes its direction, piston will strike cylinde…

Crankshaft

Due to its nature of operation, there are several types of forces which come to act upon the crankshaft of engines used in marine propulsion. You will get a better idea about these forces if you take a close look at the image shown below which shows the various twisting and bending forces.
As can be seen from the figure, these forces are due to a variety of factors including but not limited to the weight of the pistons, combustion loads, the axial load from the propeller which is immersed in the sea, compressive loads of webs on journals and so forth.Most of these forces have alternating patterns which gives rise to fatigue and the materials used for construction need to have substantial Ultimate Tensile Strength. Apart from that the other properties required in the material of a crankshaft are wear resistance, tensile strength, and ductility.The material for construction also depends on the speed on the engine and slow speed marine diesel engines have crankshafts fabricated out of pla…

Engine Bed Plate

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IntroductionA solid foundation is necessary for any structure, be it on the ground or meant for the sea. No doubt this axiom applies equally well to marine diesel engines which are huge and gigantic structures and have a lot of forces apart from their weight, such as the reactive forces when the huge piston rush up and down through the cylinders. It goes without saying that a very strong base is required to support such load and forces and the bedplate of the engine servers as the structural base of the engine. It acts as housing for the huge crankshaft while it also supports the cylinder block. In this article we will see about the role and functions of the bedplate and learn about its usefulness and purpose. The BedplateIf you want to get an idea about the magnitude of weight which is being supported by the bedplate as well as have a general idea about the size of a marine engine just take a look at the picture below. You will notice a red coloured circle with a pointer and that is m…