Feature Post

Monday, October 24, 2011

2 Stoke Engine


Two engines are available almost everywhere these days. They are used in dozens of applications and a variety of models for all the work and recreation, the production of electricity. Two engines are differences in the design and operating conditions that require different chemical oil than their four-stroke. In order to recommend a lubricant for two stroke engines, this engine must know how it works, why it is used in place of a four-stroke engine, and where and what kind of applications that are used.

What is a two-stroke engine?


The terms "two cycles" and "two times" are often inter-changed when it comes to two-stroke engines. These engines derive their name from the amount of directional changes that the pistons do in each power stroke. Internal combustion engines used to produce mechanical energy of the chemical energy contained in hydrocarbons. The power part of the production cycle of the engine begins operating within the engine cylinders with a compression process. After this compression, combustion of fuel-air mixture then releases the chemical energy of fuel and produces high-temperature, high pressure combustion products. These gases then expand within each cylinder and transfer work to the piston. Thus, when the motor operates continuously, the mechanical energy produced. Each upward or downward movement of the piston is called a stroke. There are two cycles commonly used internal combustion engines: two-stroke cycle and four times.

What are the different two-stroke four-stroke engine?


The fundamental difference between two-stroke engines and four-stroke engines in the process of gas exchange, or more simply, the exhaust outlet at the end of each expansion process and the induction of a fresh mixture for the next cycle. The two-stroke engine has an extension, or movement of energy in each cylinder during each revolution of the crankshaft. The exhaust and the charging process occurs while the piston moves through its central position the lower or lower.

In a four-stroke engine, the gases burned during the first piston to move upward stroke, and then fresh charge to enter the cylinder during the next race down. This means that the four-engine two full turns of the engine power stroke, compared to the single turn necessary in a two-stroke engine. In other words, two motors are operated 360 degrees of crankshaft rotation, while the four engines that operate at 720 degrees of crankshaft rotation.

 





When using two stroke engines?

Two cycle engines are inexpensive to build and operate than four-stroke engines. They are lighter and can also produce a higher power to weight. For these reasons, two-stroke engines are very useful in applications such as chainsaws, outboard motors Weedeaters, lawnmowers and motorcycles, to name a few. Two cycle engines are also easier to start at low temperatures. Part of this may be due to its design and the absence of a sink. This is one reason why these engines are also commonly used in snowmobiles and snow blowers.

Some advantages and disadvantages of two-stroke engines

Because two-stroke engines can effectively double the number of power strokes per unit time compared to four stroke engines, the power is greater. However, it increases by a factor of two. The outputs of the two-stroke engines ranging from only 20 to 60 percent larger than the size equivalent to four cycles of the units. This increase is lower than expected is the result of poorer than ideal charging efficiency, or in other words, incomplete filling of the cylinder volume with fresh fuel and air. There is also a major drawback in this case the transfer of power. The higher frequency of combustion events in the results of two-stroke engines at high average rates of heat transfer from hot gases burned in the walls of the engine's combustion chamber. Higher temperatures and thermal stresses in the cylinder head (especially on the piston crown) result.

Traditional two engines are also not effective because of the washing effect allows up to 30 percent of unburned fuel / oil mixture of exhaust gases. In addition, a portion of the exhaust gases is the combustion chamber during the cycle. This inefficiency contribute to the loss of power compared to the four engines and explains why the two motors can be achieved only up to 60 percent more power.

How are the two-stroke engines are lubricated?


Two cycle engine lubrication systems considered total loss of its kind. Because housing is an integral part of the admissions process, can not act as an oil sump as is found in four-stroke engines. Lubricants traditional two-stroke engines is performed by mixing the oil with fuel. The oil is burned in the combustion air / fuel mixture. Direct injection engines are different because the fuel is injected directly into the combustion chamber while the oil is injected directly into the crankcase. This process is efficient because the fuel is injected after the exhaust port closes, and therefore more complete combustion of fuel produces more power and develops. Direct injection engines have a higher power density than traditional two-stroke engines. Because oil is injected directly into the crankcase, less oil is needed and the results of lower consumption of oil (80:1 wide). Direct injection engines have higher combustion temperatures, often up to 120F. They also require more lubrication than conventional two-stroke engines.

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