The title of diesel engines, which are also known as high pressure ignition engines, is adapted from the name of Dr. Rudolph Diesel, who patented its invention in Germany around 1893. The 6EY26W marine diesel engine is considered as an internal combustion engine because the ignition takes place inside the engine. The basis of this type of engine in terms of construction and design is similar to gasoline engines, which is also a type of internal combustion engine, but their difference is in the way fuel enters the engine cylinders and the way combustion occurs.
In gasoline engines, fuel is mixed with air and enters the cylinder, and ignition is caused by an electric spark from the spark plug. In diesel engines, the fuel is pulverized and injected into the cylinder, and ignition occurs due to the high temperature inside the cylinders.
The name of high pressure ignition is chosen based on engine performance. The 6EY26W marine diesel engine is designed based on high pressure ratio, which increases the temperature of compressed air inside the combustion chamber as a result of high pressure. The temperature is high enough for ignition to occur after fuel is injected into the combustion chamber. Therefore, it can be concluded that pressure will cause ignition. For this reason, this type of engine is called high pressure ignition.
Marine diesel engine fuel system model 6EY26W
The fuel supply system in the 6EY26W marine diesel engine works in such a way that first the diesel is taken from the tank by an electric pump and after passing through the filter, it enters the high pressure pump. This pump, which takes its power from the valve shaft, raises the fuel pressure very high and compresses it into the fuel rail. This rail is common between all cylinders and all injectors branch to this rail. The injectors are mechanical-electromagnetic and act on the command of the engine control unit. At the time of fuel injection, by rotating the valve shaft and reaching the cam of the valve shaft to the bottom of the injector and compressing, this seat with the continuation of the valve rotation; The fuel enters the injector control valve and by accurately adjusting the pressure and injection time at the beginning and end and during the injection, it provides the best conditions for a perfect combustion according to the conditions of the engine, vehicle and environment. The engine control unit receives the information it needs using various sensors and controls various components including the injector.
Suction time in 6EY26W marine diesel engine
At this time, the gas valve is open and the piston moves from the top dead center to the bottom dead center. At this moment, a relative vacuum is created, which causes air to enter the cylinder.
Compression time of marine diesel engine model 6EY26W
By moving the piston to the top dead center and compressing the incoming air, the pressure will be between 30 and 60 atmospheres and the temperature will reach 500 to 700 degrees Celsius. Both valves are closed at this stage.
Power time of marine diesel engine model 6EY26W
By moving the piston towards the bottom dead center, the atomized fuel is injected from the injector into the cylinder. At this stage of the engine, the pressure is 60 to 100 atmospheres and spontaneous combustion takes place. In the third stage of diesel engine operation, both valves are closed.
Discharge time of marine diesel engine model 6EY26W
As the piston moves from the bottom dead center to the top dead center, smoke and combustion residues leave the cylinder for two main reasons.
The purpose of using a fuel delivery system in a diesel engine is to transfer fuel from the tank to the engine so that it can be sprayed into the combustion chamber and burned.
Poor pressure circuit operation
The tank is installed under the chassis and the injector pump is installed on the chassis at a higher height. Since the work of the injector pump is a high pressure pump and is not designed to draw fuel from the tank, it is necessary that the fuel is drawn from the tank by the primary pump with a pressure of 1 to 7 atmospheres and sent to the suction channel. Therefore, the primary pump in the low pressure circuit is responsible for taking the fuel from the tank and delivering it to the filter with the specified pressure, and after the filtration (refining) process, deliver it to the common channel of the injector pump.
In the low pressure circuit, an overflow valve is used, which has a piston and a spring. The task of this valve is to keep the pressure constant in the primary circuit and vapors in the circuit and possible ventilation in it.
Primary pump in marine diesel engine model 6EY26W
There is a weak pressure circuit between the tank and the filter, and its task is to draw fuel from the tank and deliver it to the injector pump's common duct. The primary pump has two types, piston and diaphragm, which is the more common piston type. This pump is also called triangular pump in repair shops. This pump is used in two types, simple and double, which are used in large, heavy-duty diesel engines of the double type.
Fuel supply circuit filter for marine diesel engine model 6EY26W
These parts are designed and manufactured with very low precision and tolerance. For example, the clearance between the plunger and the barrel is about one micron (one thousandth of a millimeter).
These two parts increase the fuel pressure up to 1000 bar or more with high precision and without a sealing device such as a ring. Therefore, it is necessary for the fuel that enters the circuits, especially high pressure, to be free of any solid and floating substances and pure. Otherwise, the inner wall of the barrel and the outer surface of the plunger will be scratched quickly and reduce the compression power of the pump. Another member that is used in the high pressure circuit and has high accuracy is the injector and its needle. This part is also vulnerable to floating particles with fuel.
Disadvantages of 6EY26W model marine diesel engine filter failure:
• Pump production pressure drop and overall power loss in the engine
• Engine smoke due to a leak in the injector And the lack of sealing of the injector needle in its seat
• Weak acceleration due to reduced production power
• Irregular operation of the engine, especially at idle speed, due to the uniform injection of the minimum required fuel in the cylinders
• Overall increase in fuel consumption
Factors influencing the price of 6EY26W marine diesel engine
But the question of what factors affect the price of diesel generators is in the minds of many industrial owners as well as contractors and they tend to get answers very quickly. Due to the variety of diesel engine and generator brands and companies Coupling as well as changing the technical specifications of the diesel engine, such as power consumption, number of cylinders, fuel system, cooling system, country of manufacture, etc., the price of diesel generators is very diverse.
On the other hand, due to the fact that diesel generators are imported, the increase in the exchange rate increases the selling price of these machines. In addition to all these issues, the selected items needed for the diesel generator, such as the canopy, ATS panel, control boards, etc., also affect the price estimate.
But in general, diesel generators depend on many factors due to the use of many mechanical and electrical parts, and the following factors will affect the price of diesel generators:
Factors affecting the price of diesel generator
Factors influencing the price of 6EY26W marine diesel engine
1- Device power
Increasing the power of the device will increase its price, so calculating the amount of energy required and preparing the diesel generator with the calculated amount will prevent additional costs from being imposed on the investor.
2- Manufacturer's brand
In Dubai diesel generators available in the market are classified into three categories, American and European, Iranian and Chinese, and the course of price change in these three categories will be downward.
3- Control panel and accessories
The control board of the diesel generator is placed next to the engine and generator, and the quality of the equipment and technology used in the board will be determined, as well as the accessories such as the battery, exhaust silencer, diesel generator chassis, fuel tank capacity, shock absorber and canopy in the price. Finished devices will be effective.
4- Device coupler
A diesel generator consists of the following three parts:
• diesel engine
• Generator
• Control panel
Connecting the engine and generator together on the spring chassis and placing a control panel next to it is called coupling. Whether this coupling is done in the country of manufacture or by the importing company will have an impact on the final price of the device.
5- Currency price
Considering that most of the diesel generators in the market are imported, it can be concluded that the changes in the currency price will bring price fluctuations for the diesel generator. Also, among other things that will affect the choice of diesel generator besides the price, the following can be mentioned:
• Device fuel consumption
• The possibility of providing parts in case of need for replacement
• Possibility of maintenance
• Purchase support and warranty
Purchase of 8EY26W marine diesel engine from Dubai Marine
To buy a marine diesel generator model 8EY26W from the Dubai Marine website, it is enough to contact our experts in the support department at the phone numbers listed on the website. We answer your questions.