With the continuous rise of fuel prices, customers pay more attention to the fuel consumption of construction machinery. In the daily use of engineering machinery, the operator should not only master the appropriate operation methods, but also maintain the electronic control system, the hydraulic system and the diesel engine fuel system and the intake system to ensure that the diesel engine works in the best state.
Maintenance of the machine is important, but you know that before these maintenance, you must also understand the correct management and use of fuel oil, otherwise the maintenance of diesel engine fuel system can be done only half the effort.
The cause of engine failure is mostly bad management of oil, water and gas.
Due to heavy workload and environmental problems, most of our construction machinery will be used under more severe working conditions. For a device, its life is directly related to the quality of maintenance. According to the statistics obtained from the after-sale Department of a well-known international brand, nearly 7 of the engine faults in the engineering machinery 名媛直播 of this brand are caused by poor management of oil, water and gas in Chengdu. This time, we will give you a brief introduction about fuel management.
First, let's take a look at: what are the pollution factors of fuel?
Usually, what we call fuel pollution generally refers to the following situations:
(1) high water content.
(2) a lot of sand and dust.
(3) the content of heavy oil is high.
(4) the content of paraffin is high.
(5) the content of sulfur is high.
Next, we will analyze the above 5 kinds of pollution of fuel oil one by one.
1, the harmfulness of water
We take the common rail diesel engine for example: in a simple way, the high water content in the fuel will accelerate the friction of the plunger, plunger sleeve and nozzle needle valve, causing the drop of the injection pressure, the bad atomization, the black smoke, the engine power drop and so on.
The conical surface of the needle valve is easy to wear, which affects the fuel injection quantity of the injector.
The normal high quality diesel oil should be less than 0.03% and the high water content will have a great impact on fuel quality, including:
(1) the viscosity decreases after the increase of the water content of the fuel, reduces the lubrication performance of the fittings of the injector and oil pump, and reduces the lubrication protection of the sealing surface of the needle valve, and speeds up the wear of the parts.
(2) the water that enters the diesel from the outside itself is not clean enough. It may contain a large amount of impurities and various inorganic salts, which will aggravate the wear and corrosion of the injector with the surface and the sealing surface.
(3) the increase of water content will lead to the multiplication of bacteria in the mailbox. At present, the sulphur content of diesel fuel is high in our market. Therefore, a lot of acidic substances will be generated, which will destroy the balance of fuel acid base and increase the corrosion degree of parts.
(4) high water content of fuel oil, its viscosity is low, the filter core surface of the filter can not form a good oil film to assist the filter to filter impurities, which will allow more large particle impurities to pass through the filter core, and the filter core will be greatly damaged under the influence of water and impurities, making the filtration capacity worse.
In a word, the effect of high water content on the injector is very serious, and it also damages the other parts of the oil supply system such as oil pump, but the fault of the injector is more easy to appear, and it has more direct impact on the performance of the engine.
2, the harmfulness of sand and dust
If the fuel is mixed with too much sand and dust, it will accelerate the friction of the injection pump plunger, the plunger sleeve, the oil outlet valve, the injection pump needle valve and the transmission pump unidirectional valve, which will cause the drop of injection pressure, the bad atomization, the black smoke and the power drop of the engine.
(1) more sand and dust in the fuel will cause wear and tear to the oil nozzle and affect the atomization quality.
(2) the sand and dust contained in the fuel contain alkali metals such as vanadium and sodium, which will form high temperature sticky ash on the high temperature heating surface tubes inside the engine.
(3) in high temperature ash, there are more than five oxidation two vanadium and compound salt containing sulphuric acid from sodium. All of them can destroy the oxidation protection film on the metal surface, which will cause high temperature corrosion to the oil outlet valve, the plunger of the injection pump, the plunger sleeve and so on.
3, the harmfulness of heavy oil
Heavy oil, also known as fuel oil, is dark black liquid, mainly from crude oil in the process of crude oil processing, vacuum residuum, FCC residue, FCC diesel and catalytic diesel oil as raw materials.
Heavy oil is the remaining heavy oil after extraction of gasoline and diesel oil, characterized by large molecular weight and high viscosity. The proportion of heavy oil is generally 0.82-0.95, and the specific heat is about 10000-11000kcal/kg. Its components are mainly hydrocarbons, and also contain some (about 0.1-4%) sulfur and trace inorganic compounds.
When the heavy oil mixed with fuel is injected into the cylinder, large carbon particles will be formed because it can not be quickly and completely burned, which will cause the blockage of the nozzle.
4. The harmfulness of paraffin
The viscosity of fuel (diesel) itself is large, and viscosity will become larger as the temperature drops, that is, the fuel oil (diesel) has poor fluidity at low temperature.
Fuel contains a certain amount of paraffin wax. At low temperature, paraffin wax tends to crystallize, resulting in poor fluidity of fuel. The lower the temperature, the more obvious the crystallization of paraffin, and even the crystallization network will eventually lead to the loss of fluidity of the fuel.
At low temperature, the fluidity of fuel oil is not good. The fuel can not pass through the oil pipe and filter, and the oil pipe and filter core are blocked. The fuel supply can be reduced or even interrupted. The engine can not work normally (starting difficulty) or even extinguish (unable to start).
5, the harmfulness of sulfur
What is "national four Diesel"?
State four diesel refers to diesel whose sulfur content is not greater than 50ppm. Many people only know the use of fuel oil, but do not understand why to use low sulfur fuel, in fact, this is not only because of environmental protection, energy saving and emission reduction, the most direct benefit is to reduce the damage to the internal parts of the engine.
In fact, the answer is simple. The sulphur in the fuel will produce acid after burning. It will appear as follows:
(1) speed up the deterioration of the oil.
(2) corrosion of the inner surface of the body.
High sulfur content in diesel oil is easy to generate strong acid after combustion, and strong acid can cause and aggravate corrosion and wear of engine components. For example, the gas phase corrosion of the engine combustor and exhaust system is easily condensed into sulphuric acid (H2SO4), attached to various parts of the cylinder and exhaust system, and produces strong liquid corrosion to the metal. Moreover, this will also promote the formation of carbon and harden carbon deposition. These carbon deposits attached to parts will aggravate mechanical wear.
The three sulfur dioxide produced in the combustion process can capture some floating particulate dust. When the metal parts with lower surface temperature are encountered, they will carry the captured dust and adhere to the metal surface together, and continue to adsorb some floating dust, thus forming a sedimentation layer. Once the deposit is formed, the thermal conductivity of the metal will decrease rapidly and the temperature will increase rapidly, leading to high temperature corrosion of metals. Therefore, the sulphide content in diesel oil should not be too high.
Two, little details you don't know, right or wrong in diesel management.
Error 1, the oil barrel is too dirty
The reason for the mistake is that the clean diesel oil will also be stained.
Correct: oil barrel, wash clean. The funnel and the oil bucket should be cleaned.
Error 2, oil drum: pour the oil drum down and roll to the front of the machine.
The reason for the mistake is that after rolling down, the water and impurities that originally deposited to the bottom of the bucket are mixed with diesel oil.
The correct way: we should carefully precipitate the diesel oil and send it to the machine by the trolley.
Error 3. Input diesel oil with dirty pipes
The wrong reason: dirty things go into the tank together with diesel.
The correct way: clean the tubing with filter material (such as stockings) for fuel filtration, you can reject impurities outside the tank.
Mistake 4, put oil drum at high place, insert oil tube for refueling.
The reason for the mistake is not safe. If there is dirty substance in the oil drum, the dirt will enter the fuel tank along the tubing because of the pressure in the tubing.
The correct way: no ordinary oil pipe, and the use of hand pump to pump equipment is a good solution. (Note: the hand pump is available on the market)
Three, daily management of fuel oil
When we buy the diesel oil needed for the engineering machinery and equipment, we must not ignore the management of the oil barrel. The correct storage of the fuel can avoid many unnecessary failures.
1, before buying, we must control the quality of incoming goods; after purchase, we should strengthen the management of the stock.
Matters needing attention:
(1) control the purchase channel, do not buy fuel mixed with water, sand and oil.
(2) attention must be given to the prohibition of smoking and fire in places where fuel is concentrated.
(3) when placing the fuel barrels in the open air, we should try to place the ground in a horizontal way, and should pay attention to the cover (cloth and plastic cloth) to prevent the mixing of rain in the fuel tank.
(4) when placing the fuel tank, if it must be placed, pay attention to the bottom side of the fuel barrel, so that one side of the bucket will be able to rise up to put the oil out Kong Zhong on the top of the bucket.
(5) the fuel barrel in half box is placed in the way of horizontal inversion and leveling, so that the oil surface of the barrel is higher than the position of the oil hole, in order to prevent the air from inhaling.
2. When the construction machinery works, choose the right fuel according to the ambient temperature so as to prevent the oil from freezing.
The brand name of diesel represents the freezing point of diesel oil, and the diesel that loses its fluidity at 0 degrees Celsius is No. 0 diesel oil, and so on. When using, we should use the temperature at that time to choose the appropriate brand. The general grade should be below 5-10 degrees Celsius to ensure the normal operation of the diesel engine.
Pay attention to the use of the appropriate brand of diesel oil:
The lowest temperature in a day is higher than 0 degrees Celsius: 0 diesel should be selected.
The lowest temperature in a day is -10 degrees Celsius to 0 degrees Celsius: -10 diesel should be chosen.
The lowest temperature in a day is -20 degrees Celsius to -10 degrees Celsius: -20 diesel should be chosen.
The lowest temperature in a day is -20 degrees Celsius to -30 degrees Celsius: -35 diesel should be chosen.
The lowest temperature in a day is below -30 degrees Celsius: -50 diesel should be chosen.
3. We suggest that users fill up fuel immediately after the end of each day's work.
Fill up the fuel immediately after the work is finished, and drain water from the oil tank and oil separator before starting every day.
The fuel tank is filled with oil to drive the air out, otherwise the moisture in the air will be condensed and mixed into the fuel.
The oil and water separator is cleaned up for discharging water and sundries deposited at the bottom of the tank.
4, replace the genuine fuel filter according to the required maintenance time.
Each machine has the maintenance manual, which has the most detailed explanation and annotation for the operation and maintenance of the machine. You can study carefully, for a variety of reasons, many owners and drivers have never seen the "maintenance manual". It is a great waste to rely on the teacher or to maintain the machine by my own experience. It is suggested that you find the maintenance manual you bought when you buy a car and put it in the driver's cab for your reference.
There will be some notes on the replacement time of the engine fuel filter in the maintenance manual. We suggest that you use the genuine fuel filter cartridge of the original factory. The reasons are actually told thousands of times. For example, the use of filter cartridge is like drinking milk. The price of good milk is expensive but good quality, cheap may be melamine. If you want to keep the engine alive for several years, you suggest using genuine accessories.
