1. Performance and use of oil
In agricultural machinery, oil costs account for one-third of the total cost. At the same time, the correct use of oil can extend the service life of the machine and reduce the repair cost, which is of great significance for improving production efficiency.
Petroleum is mainly a compound composed of carbon and hydrogen. Each petroleum product is refined according to the boiling point of various compounds of its composition. By distillation, according to different temperature ranges, products such as gasoline, diesel and lubricating oil can be extracted.
2. Several oil materials commonly used in agricultural machinery
(1) Gasoline
You must understand several of its performance metrics when using it. Such as octane number, distillation range, saturated vapor pressure, and the like.
The 1 octane number is an indicator of the antiknock performance of gasoline. The larger the octane number, the better the antiknock performance. In order to increase the octane number of gasoline. Lead can be used as a catalyst to add gasoline.
2 distillation range refers to the boiling point of the oil at the specified temperature. The percentage of evaporated components in a certain temperature range is an indicator for evaluating the evaporation performance of the oil. If the 50% distillation temperature of the oil is low, it indicates that the oil has good evaporability. If the 90% distillation temperature of the oil is low, the heavy fraction content is small, and the carbon deposition during combustion can be reduced.
3 saturated vapor pressure is one of the indicators to determine the evaporation performance of gasoline. Generally, gasoline with high evaporation performance is more evaporative, but if it is too large, it will easily form a gas barrier and block the inlet pipe.
Therefore, it is stipulated that the vapor pressure of gasoline should not be greater than 500 mmHg, and we will be called the saturated vapor pressure of vapor pressure which is large in evaporation and difficult to form a gas barrier.
(2) Diesel
Diesel is the main food for agricultural power machinery. When using it, you must understand the following performance indicators.
1 viscosity. It refers to the indicator of the degree of diluteness and fluidity of diesel at room temperature. The viscosity is large, the flow is difficult, the atomization quality is poor, the air is mixed unevenly, the combustion is bad, the black smoke is emitted; the viscosity is low, the column ring is not well sealed, the leakage is easy, the shape is not oil film, and the parts are easy to wear.
2 The freezing point is a temperature indicating the loss of fluidity of the oil. When the temperature drops to the point where the diesel loses fluidity and solidifies, the temperature is called the freezing point. In order for the engine to operate normally at low temperatures, diesel fuel is required to have a lower freezing point. China has set the freezing point as the grade of diesel.
3 The distillation range is one of the indexes for determining the evaporation performance of diesel oil. It is usually expressed by the volume percentage expressed at the specified temperature or the volume percentage of the distillate. For diesel fuel, the evaporation is short due to the mixed combustion of diesel fuel. If it is not good, it will not be able to evaporate and burn incompletely. Therefore, high-speed diesel engines use light diesel oil with low distillation range, while low-speed diesel engines use heavy diesel oil.
4 Cetane number is an important indicator to assess the degree of crudeness of diesel in the combustion process. The higher the cetane number, the lower the natural ignition temperature, and the easier the ignition, but the cetane number should not be too high. When it is greater than 65, the engine emits black smoke and the fuel consumption increases. Therefore, the cetane number of diesel is generally specified between 40 and 60.
5 flash point to heat the oil under the specified conditions. Its vapor is mixed with air and a flash occurs when it comes into contact with the flame. The temperature of the oil at this time is called the flash point. The height of the flash point indicates the stability of the oil at high temperatures.
In addition, diesel oil is also corrosive, carbon depositing and gelling. Only when you understand the performance indicators of diesel can you correctly choose the grade of diesel. The grade of diesel is indicated by the freezing point. The diesel oils currently used in agricultural machinery in China are No. 0, No. 10, No. 20, No. 35 and No. 20 for agricultural use. Their freezing points are 0 ° C, 10 ° C, 20 ° C, 35 ° C, + 20 ° C, depending on local climatic conditions.
(3) Lubricating oil
Lubricating oil is the main oil used to reduce the wear and friction heat on the surface of friction parts in the machine. Modern lubricating oil also has the functions of cleaning, dispersing and anti-oxidation. According to the use, it can be divided into turbine oil, diesel engine oil and gear oil. Here are some related parameters.
1 lubricating oil viscosity. It is used to indicate the ease of oil flow, which is directly related to the fluidity of the lubricating oil and the thickness of the oil film formed on the two friction surfaces. Lubricating oils with high viscosity cannot flow to the friction surface of the fittings with small gaps and cannot be lubricated. However, it can withstand a large pressure load and is not easily extruded from the friction surface while maintaining a certain thickness of the oil film.
2 The condensation point of the lubricating oil. It is the temperature indicating the loss of fluidity of the oil. For lubricating oil, when the weather is cold, the oil condenses and the performance of the lubricating oil is significantly deteriorated. Therefore, the machine working at low temperature should select the lubricating oil with low freezing point.
3 floating. It is an indicator indicating that the formation of a film and precipitation is suppressed. The well-floating lubricating oil can suspend the oxide in the oil and not deposit on the surface of the metal part to avoid the formation of the gel film.
4 corrosive. Oxidation of acid, alkali medium or oil in lubricating oil to produce organic acid will cause chemical action on the metal surface, causing changes in metal composition and properties, causing damage to the metal, and causing such changes in metal composition and properties to be called corrosive.
The grade of turbine oil is classified according to the kinematic viscosity at 100 °C. It has several types of No. 6, No. 10, No. 15, No. 6 low condensing machine oil and No. 8 low condensing machine oil. The higher the grade, the higher the viscosity.
Diesel oil is divided into 8th, 11th, 14th, 16th, 20th, 11th low oil and 1l thickened oil No. 14 thickened oil according to the 100 °C kinematic viscosity. The higher the grade, the higher the viscosity. The choice of diesel engine oil depends on the alloy material of the diesel engine crankshaft bushing. If it is a babbitt alloy (tin-based copper alloy), it can be used as motor oil. If it is a lead bronze alloy, cadmium nickel alloy should use diesel engine oil.
Gear oils are classified into gear oils and hyperbolic gear oils depending on the application. According to the 100 °C kinematic viscosity gear oil is divided into 20, 30 and general gear oil; hyperbolic gear oil is divided into 22 and 28. According to the production process, there is another synthetic No. 13 hyperbolic gear oil.
Various grades of hyperbolic gear oils are supplemented with anti-wear additives. Has good anti-wear properties. It cannot be replaced with gear oil without additives.
(4) Grease
Grease, commonly known as butter, is made from lubricating oils and thickeners. Grease is classified into three types: calcium-based grease, sodium-based grease and calcium-sodium-based grease depending on the thickener added. It is creamy at room temperature, and it has good pressure resistance and good cushioning. It is not easy to lose. It has good sealing property and good viscosity temperature, and is suitable for lubricating parts with difficult lubrication, heavy load, high temperature and long time without replacement. It is necessary to know the indicators such as the penetration degree of the lubricating oil, the dropping point, and the safety of the colloid.
There are five grades of calcium-based grease currently produced in China:
ZG-1, ZG-2, ZG-3, ZG-4, ZG-5
"Z" means "fat", "G" means "calcium", and l 2 3 4 5 is a serial number of penetration, indicating the size of the grease consistency.
The sodium-based greases currently produced in China are available in three grades: ZN-1H, ZN-2H, and ZN-3H. "N" means "sodium", and the others are as described above.
The grades of calcium-sodium-based greases No. 1, No. 2, and grease are differentiated according to the degree of penetration. The smaller the penetration, the higher the grade, the greater the consistency, and the harder the grease.
[Follow the WeChat public number "Jiuzheng Paint Network"; pay attention to surprises, scan code to view "If your husband is selling paint..." Jiuzheng Coating Network Exchange Group]
Tempered Glass is a heat toughened safety glass. It has undergone a special heat treatment to increase its strength and resistance to impact. Actually, large tempered glass is approximately five times more resistant than normal glass. As example, one piece of 8mm Toughened Glass will be able to withstand a steel ball weighing 500gr dropped from a height of 2 meters.
Tempered Glass
Tempered Glass,Glass Shower Doors,Tempered Glass Windows,Glass Balustrade Stairs
Jinan Coton Glass Co., Ltd , https://www.cotonglass.com