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Erica Zhu Feilong Jiangli

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  1. Erica Zhu Feilong Jiangli

    Viscosity tester

    Viscosity tester is used to measure the intrinsic viscosity of polymer solution. It is suitable for the intrinsic viscosity measurement of synthetic fiber industry, printing and dyeing industry, rubber industry and petrochemical industry. The viscosity tester has the following characteristics: 1. The instrument is measured by capillary viscometer (modified Uli viscosity tube) and 2--5 samples can be measured at one time. 2. Using computer control, screen display, Windows interface, automatic determination process, sample preparation, the entire determination process without manual intervention. 3. Solvent, the number of measurements of the liquid under test and the balance time between sample temperature and sink can be set manually and timed automatically. 4, the water tank temperature is set at 50 degrees, automatically adjust. 5, the results are printed and output, and the output is perfect and intuitive. 6, equipped with circulating water refrigeration system. 7. The instrument is simple to operate, easy to use and reliable in performance. Feilong Jiangli rubber parts viscosity testing professional and efficient, welcome to order customized automotive rubber products. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  2. Erica Zhu Feilong Jiangli

    New automotive materials

    [Feilong Jiangli Edition] Although the proportion of heat-resistant materials in automobiles is small, they are all important parts of the engine is very important, has a great impact. Such as the high temperature part of the combustion chamber, the diesel engine's pre combustion chamber exhaust system, turbocharger, catalytic converter and so on. These components have high performance requirements: high temperature strength, small thermal expansion coefficient, processing performance, high temperature oxidation resistance, high temperature corrosion resistance, lightweight and so on. The new materials currently used include: high silicon material, chromite heat-resistant alloy, austenitic stainless steel and so on. Composite steel is a laminated material bonded by steel plate and plastic and other non-metallic materials, with corrosion resistance, vibration reduction, sound insulation, lightweight and other advantages, suitable for making automotive panels (such as engine cover), oil pan, air filter, etc. As a substitute for steel, lightweight materials mainly include aluminum, magnesium, titanium and other light metals, aluminum alloy is the most widely used, is an important development direction of automotive materials in the future. Magnesium is the lightest metal, and its density is 2/3 of aluminum, but the cost of production is higher. The commonly used die casting magnesium alloys are mainly used for manufacturing grille, transmission handle, transmission housing, etc. The main characteristics of titanium alloy are high temperature strength, good corrosion resistance, density is 1/2 of iron, but also the disadvantages of high production costs, can not be used in large quantities at present, only for the manufacture of a few parts of high-grade cars.
  3. [Feilong Jiangli Edition] Other metals except ferrous metals are collectively referred to as nonferrous metals. Aluminum, copper and its alloys are commonly used in automobile production. Pure aluminium: Pure aluminium is a light metal material with a melting point of 660 C and a density of 1/3 of iron. Its conductivity and thermal conductivity are second only to silver and copper. It has good oxidation resistance and atmospheric corrosion resistance. Pure aluminum has very low strength and hardness, but its plasticity is very high. It can not be used as structural parts. Aluminum alloy: Aluminum alloy is an alloy obtained by adding proper amount of tin, copper, magnesium, manganese and other elements into aluminum. After treatment, the mechanical properties of aluminum alloy are greatly improved. Aluminum alloy has high specific strength, good corrosion resistance, machinability and foundry, flexible strength design and beautiful surface can be achieved. It is obtained on automobiles. To a wide range of applications. For example, casting aluminum alloy is used to make cylinder block, cylinder head, rim and bumper, aluminum alloy is used to make radiator, condenser and other parts; aluminum and aluminum alloy are widely used in automobiles, on the one hand, the performance of these parts is improved, on the other hand, the lightweight of automobiles is achieved, which is an important development of Automotive materials in the future. The direction of the exhibition.
  4. 【Feilong Jiangli Edition】}Alloy steel refers to the steel grade formed by purposefully adding one or more alloy elements on the basis of carbon steel in order to improve some properties of steel. Alloying elements have great influence on the properties of steel. For example, adding chromium into carbon steel can improve the strength, hardness and corrosion resistance of steel. Adding nickel can not only improve the strength of steel, but also reduce its toughness. Adding silicon can improve the strength, hardness, fatigue strength and corrosion resistance of steel. The simultaneous use of several alloying elements has a more significant effect on the properties of steel than a single alloy element. Only after heat treatment can the alloy steel achieve the purpose of improving its mechanical properties. There are many kinds of alloy steels, which can be roughly divided into the following categories according to their uses: alloy structural steels, alloy tool steels, special performance steels. Alloy structural steels include low alloy structural steels, alloy carburizing steels and alloy quenched and tempered steels. Low-alloy structural steels: steels based on low-carbon steels with a small amount of alloy elements (3% - 5%); these steels have a strength of 10% - 30% higher than carbon steels with the same carbon content, and have good plasticity, toughness and weldability. Because of its simplicity in smelting, its production cost is similar to that of carbon steel, it is widely used to make various machine parts and engineering components, such as frame longitudinal beam, cross beam, engine lug, etc., and substituting low alloy structural steel for carbon structural steel can save steel, reduce weight and use reliably. Commonly used steel species are 12MnV, 16Mn and so on. Alloy carburized steel: parts made of alloy carburized steel, after heat treatment, not only have higher surface hardness and wear resistance, but also can greatly improve the strength and toughness of the center of the parts, thereby improving the ability to resist impact loads; automotive parts withstand high speed, heavy load, strong impact and severe friction, such as piston pins, gears, shafts Parts and important bolts are made of alloy carburized steel after heat treatment. Alloy quenched and tempered steel: Alloy quenched and tempered steel refers to the steel used after quenched and tempered, with high strength and toughness. If quenched and tempered and then quenched, the wear resistance of parts surface can be improved. It is often used to manufacture parts bearing heavy load and impact load. Such as machine tool spindle, automobile half shaft, connecting rod, steering knuckle, etc. Other alloy steels and special performance steels: commonly used steel alloy spring steel, rolling bearing steel, alloy tool steel, weathering steel (good atmospheric corrosion resistance), stainless steel, wear-resistant steel, heat-resistant steel.
  5. There are many kinds of materials used to produce automobiles: iron and steel, non-ferrous metals, plastics, rubber, glass, ceramics and so on. According to statistics, in recent years, the weight composition ratio of the main materials of an ordinary car is approximately 65%-70%, 10%-15% of non-ferrous metals, and 20% of non-metallic materials. Various new materials, such as light metal materials, composite materials, high-tech synthetic materials, are increasingly used in modern automobiles. Metal materials have various properties. It has physical and chemical properties, mechanical properties and process properties. Physical and chemical properties refer to the properties of metal materials under various physical conditions and the ability to resist the erosion of various chemical media. Density: mass per unit volume; thermal conductivity: the ability to conduct heat; electrical conductivity: the ability to conduct electric current; thermal expansion: the ability to increase volume when heated; melting point: the temperature when the solid state becomes liquid; magnetism: the magnetic conductivity of metallic materials is called magnetism; corrosion resistance: metal resists the occurrence of the surrounding medium at room temperature The ability of chemical reactions to be destroyed; oxidation resistance: the ability of metals to resist oxidation at high temperatures. Mechanical performance refers to the resistance of metallic materials under various loads (external forces). It has the following indicators: Castability: Castability refers to the fluidity of liquid metals, the size of shrinkage segregation during cooling and solidification (inhomogeneity of chemical composition and microstructure of solidified metals), and the removal and absorption of gases. Pressure Processing Performance: Pressure Processing Performance refers to the ability of metal to produce deformation without destroying in cold and hot conditions, and the greater the plasticity, the smaller the deformation resistance, the better the pressure processing performance. Welding performance: Welding performance refers to the two pieces of metal materials in the local heating to the melting state, can be firmly welded together; Welding is good, easy to use general methods and processes to weld, welding is not easy to form cracks, porosity, slag inclusion and other defects, weld strength can be similar to raw materials. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  6. Erica Zhu Feilong Jiangli

    Air spray repair auto parts

    The significance of automotive parts repair is to repair old and waste, reduce the consumption of new parts, thereby saving raw materials, energy and manpower for manufacturing parts. The damage of automobile parts mainly includes four types: deformation, fracture, corrosion and wear. The first three types of damage are usually repaired by cold working, hot working or gluing. If the general parts deformation can be cold-pressed or hot-pressed after correction for mechanical repair; shaft parts can be broken by inlaying, welding, forging and other methods to repair; cylinder block water jacket cracks can be repaired by welding, riveting or adhesive methods. Parts wear is the most common damage. Parts that have not worn out beyond the specified repair size are processed according to repair size. Parts that have worn out beyond the repair size are repaired by surfacing, spraying, electroplating and other metal covering processes and adhesive methods. Spraying Repair This method uses high-speed airflow to spray the molten metal onto the worn surface of the part to restore its original size. The spraying process includes arc spraying, air spraying and plasma spraying. The spray coating formed by various spraying is made up of small metal particles. Each particle is coated with an oxide film, and the particles and the matrix metal are simply mechanically squeezed together, without fusion, so the general strength of the sprayed coating itself and the bonding strength of the sprayed coating with the substrate is not high (14kg/mm2). There are about 10% pores in the spray coating, which is beneficial to the adsorption of lubricant film, but not conducive to the impact load and greater contact stress. Oxygen acetylene flame is used for gas spraying to melt metals, which are sprayed onto the surface of the parts by compressed air. The characteristics and uses of air spraying are the same as those of electric spraying. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  7. Erica Zhu Feilong Jiangli

    Auto parts repair

    The significance of automotive parts repair is to repair old and waste, reduce the consumption of new parts, thereby saving raw materials, energy and manpower for manufacturing parts. The damage of automobile parts mainly includes four types: deformation, fracture, corrosion and wear. The first three types of damage are usually repaired by cold working, hot working or gluing. If the general parts deformation can be cold-pressed or hot-pressed after correction for mechanical repair; shaft parts can be broken by inlaying, welding, forging and other methods to repair; cylinder block water jacket cracks can be repaired by welding, riveting or adhesive methods. Parts wear is the most common damage. Parts that have not worn out beyond the specified repair size are processed according to repair size. Parts that have worn out beyond the repair size are repaired by surfacing, spraying, electroplating and other metal covering processes and adhesive methods. Surfacing repairing is a repairing method in which a layer of metal is surfaced on the worn surface of a part and then processed to restore the part to its original size. The advantages of this method are as follows: the welding layer fuses with the substrate, and the bonding strength is high; the suitable electrode or wire can be selected according to the needs of the parts, so as to control the chemical composition of the surfacing layer. The disadvantage is that the parts have large deformation after welding. The surfacing method is manual surfacing and automatic surfacing. Manual surfacing has two processes: arc welding and oxygen acetylene welding. Manual surfacing equipment is simple and widely used in automobile maintenance enterprises. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  8. Erica Zhu Feilong Jiangli

    Cleanliness of automobile parts

    With the development of parts cleaning technology and application, the cleanliness requirements of automotive parts have become particularly stringent. The establishment of cleanliness standards and standards for automotive parts involves five steps and problems: the size of the parts; the nature of pollutants; necessary cleanliness; cleaning process and cleanliness testing and verification. First, the size of the parts is the basis for designing an efficient cleaning process. Accurate dimension, tolerance and material composition of components are essential parameters. Material in particular should not be neglected, because in the cleaning process, chemicals will produce corrosive physical cleaning will lead to thermal expansion and change the size of parts. The second step is the quality and quantity of contaminants that need to be washed, which is an important variable of cleanliness. Before cleaning, the cleanliness of components should be tested, such as using a balance as a weighing method to detect the weight of pollutants, using a full-automatic cleanliness testing scanning microscope or laser particle size analyzer to detect the size, quantity, shape, nature of non-corrupt particles, and so on, in order to select a suitable cleaning machine. Accurate and comprehensive testing of cleanliness to determine the nature and quantity of pollutants is not only the result of sampling, but also related to the reasonable and correct parts cleaning process. Understanding the nature of pollutants helps to better maintain the cleaning machine and extend its service life. The third step is to determine the cleanliness of the baseline level. The cleanliness level is set on a slightly higher specification. There is no need to set it too high. The fourth step is to determine the cleaning process. According to the three elements of mechanical action, chemical reaction and material handling, the cleanliness control process is designed. The last step is to do an accurate and comprehensive cleanliness test. To use cleanliness testing equipment to do an accurate and comprehensive test of a cleaning process to ensure that the washing machine can reach the clean standard, without damage to parts.
  9. Erica Zhu Feilong Jiangli

    Inspection of automobile shaft parts

    There are many kinds of automotive shaft parts, such as crankshaft, camshaft, transmission shaft, transmission shaft and so on. The common damages of shaft parts in use include bending, wear (roundness, cylindricity) and fracture. The inspection methods are as follows. (1) bend. The two ends of the axle are supported horizontally with V-shaped iron, so that the dial stylus is placed on the middle journal, and then the slowly rotating axle is rotated one week to observe and record the oscillation of the stylus. The maximum value of the pendulum of the stylus reflects the degree of bending of the axle (half of the pendulum is the actual degree of bending of the axle). The allowable amount of bending of many axles on automobiles is very small. This must be carefully inspected for some simple shapes of shaft, such as variable speed slides, can be placed directly on the plate rolling, rolling to observe the change of light leakage between the shaft and the platform, so as to determine whether the shaft is bent. (2) wear and tear. Wear of shaft is usually checked by external diameter micrometer. For the shaft with uniform wear, the outer diameter of the felt should be checked only, but for some shaft with uneven wear, the roundness and cylindricity should also be checked. When measuring, it is measured on both sides of the neck oil hole and then measured at 90 degree. 1/2 of the maximum difference on the same section of the journal is the roundness value; 1/2 of the maximum difference on different longitudinal sections of the journal is the cylindricity value. (3) fracture. It can be checked by inspection and nondestructive testing. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  10. Erica Zhu Feilong Jiangli

    Automobile parts inspection method

    Inspection of automobile parts can be made by measuring instrument and nondestructive testing. Measuring instrument (instrument) measurement method: The change of dimension and geometry of parts caused by wear or deformation, or the decrease of technical performance (such as spring elasticity) caused by long-term use. Generally, the existing size and data can be measured by measuring tools and instruments, and whether the parts need to be repaired (or replaced) or continue to use the quantity commonly used for inspection can be determined by comparing the allowable technical standards. The instruments commonly used for inspection are: micrometers, external micrometers, vernier calipers, gauges and other special measuring instruments. Spring tester, bearing tester, front beam ruler and other measuring tools and instruments used to test parts, generally can obtain more accurate data. But in order to operate correctly, at the same time, we must carefully check the accuracy of the gauge itself before the measurement, the selection of measuring parts and the reading of the instrument and gauge should be correct. NDT: It is very important to inspect the concealed defects of parts, especially the tiny cracks of crankshaft and steering knuckle in automobiles, for ensuring the quality of automobile maintenance and driving safety. Commonly used detection methods are: magnetic flaw detection, X ray detection, ultrasonic flaw detection and so on. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  11. Erica Zhu Feilong Jiangli

    Boring of automobile parts

    Boring is based on the rotary motion of boring cutter as the main movement, and the cutting hole of the workpiece is expanded. In the expanding processing of auto parts holes, boring occupies a large proportion. Boring can be carried out in combination boring machine, Jin Gang boring machine and milling and boring machining center. Boring on combined boring machine is based on the combination of boring machine and boring machine tool spindle can be divided into rigid spindle boring and floating guide boring. Fine boring is a method of boring with high cutting speed and small feed rate by using diamond or cemented carbide boring cutter with proper geometric angle and careful grinding. At present, cemented carbide, synthetic diamond CBN, ceramics and other superhard materials are widely used for small boring and boring tools. Fine boring has high cutting speed, small back feed and feed, and high machining quality. Fine boring is very sensitive to vibration. When a machine tool with heavy load is working nearby, vibration will be transmitted through the ground to increase the roughness of the machined surface. When boring, the boring bar is suspended and the rigidity is poor. In order to reduce vibration, the vibration eliminating boring bar is often used. https://s1.ax1x.com/2018/08/22/Po50z9.jpg
  12. Erica Zhu Feilong Jiangli

    Cavitation of automotive parts

    Cavitation is a damage phenomenon on the surface of a component when it contacts and moves relative to the liquid. Cavitation corrosion may occur on the surface of the wet cylinder liner contacting the coolant and on the oil film diffusion part of the journal bearing after the minimum oil film gap (due to the existence of negative pressure). Cavitation is the surface fatigue damage caused by impact force, but the chemical and electrochemical action of the liquid and the inclusion of impurities in the liquid abrasive may accelerate the caving damage process. Taking the cavitation erosion of the cylinder liner in Feilong Jiangli as an example, the cylinder liner has elastic deformation and high frequency vibration due to the change of combustion pressure with the crankshaft angle. Bubbles burst instantaneously with great impact (tens or even tens of thousands of atmospheric pressures) and high temperatures (hundreds of degrees) at speeds up to 250m/s. The outer wall of the Feilong Jiangli cylinder liner is subjected to the repeated impact stress, which makes the surface material fatigue and gradually fall off, forming pits, then expanding and deepening, when serious, honeycomb-like cavities aggregate, and even penetrate the cylinder wall. The common feature of cavitation damage of Feilong Jiangli cylinder liner is that the cavitation groups appear on both sides of the swing plane of connecting rod, especially on the side of piston bearing high lateral pressure. In addition, cavitation erosion may also occur at the inlet and the water diversion. The measures to prevent cavitation erosion of cylinder liner are to prevent or reduce the formation of bubbles, and if bubbles inevitably occur, try to make bubbles collapse away from the parts or improve the cavitation resistance of parts. Increasing the fixed rigidity of cylinder liner (such as increasing the bearing height, reducing the fit clearance, etc.) to reduce the vibration of cylinder liner; widening the water jacket to make the cooling uniform and reduce the impact of bubble explosion; eliminating the local eddy current area and dead water area in the cooling water line, tangential water can be used; keeping the cooling water clean or adding emulsifier in the cooling water should be used; High cylinder block and piston repair quality and assembly quality will play a certain role in preventing cavitation. https://s1.ax1x.com/2018/08/22/Po50z9.jpg