Jump to content
Mechanical Engineering Community

Erica Zhu Feilong Jiangli

Members
  • Content Count

    34
  • Joined

  • Last visited

About Erica Zhu Feilong Jiangli

  • Rank
    Member

Recent Profile Visitors

121 profile views
  1. The service life of turbochargers on automobiles should be more than 150,000 kilometers if they are properly used and maintained. However, due to the improper operation of some drivers and maintenance personnel irregular maintenance: it will cause unnecessary damage to the turbocharger, so as to shorten its service life. Modern cars can start without preheating after starting, but engines with turbochargers must idle for a few minutes before starting. If the engine starts as soon as it is started, the turbocharger rotor bearing will not be fully lubricated before high-speed operation, resulting in the early damage of the rotor floating bearing. Increasing the throttle load immediately after starting will accelerate the wear and tear between the rotor shaft and the floating bearing because of the oil-free lubrication of the supercharger bearing, and even jam. The engine suddenly stalls at high speed, while the rotor in the turbocharger is still spinning at high speed due to inertia, which will cause the floating bearings to be worn out or even ablated due to high temperature and lack of lubrication. The engine with turbocharger can not run idle for a long time. Because when the engine is idling for a long time, there is negative pressure behind the turbocharger turbine and the compressor impeller. Under the pressure difference, the oil from the floating bearing will leak out. This is also one of the reasons why the turbocharger engine often has less oil.
  2. Erica Zhu Feilong Jiangli

    Fatigue of automobile parts

    Fatigue fracture is a kind of fracture that occurs after a long period of work under the action of alternating stress. Fatigue fracture is one of the common failure forms of automobile parts, and it is also one of the most harmful failure forms. According to the characteristics of parts and the total number of stress cycles, fatigue failure can be divided into: crack-free parts of the fatigue fracture failure and crack parts of the fatigue fracture failure. For different types of fatigue failure, the analysis methods are different: when high cycle fatigue occurs, the yield strength should be below, and the life of the parts is mainly controlled by the crack nucleation life. The stress of low cycle fatigue is higher than that of yield strength, and its life is greatly influenced by the crack propagation life. Generally, automobile parts are low stress and high cycle fatigue fracture. Fatigue fracture failure mechanism: Fatigue fracture of metal parts is essentially a cumulative damage process, which can be divided into slip, crack nucleation, emblem crack propagation, macroscopic crack propagation and final fracture. Methods to improve fatigue fracture resistance of automotive parts: 1) Delay the initiation time of fatigue crack: strengthen the surface of metal alloy, such as surface rolling, shot peening and surface heat treatment. Grain refinement can improve the fatigue strength limit; heat treatment can prevent grain boundaries from becoming fatigue crack propagation channels; improve the purity of metal materials, reduce the size of inclusions; improve the surface integrity of parts design level, as far as possible to avoid the phenomenon of stress concentration. 2) Reduce the rate of fatigue crack growth: the main methods are: crack arrest method: that is, drilling holes in the front of crack growth to prevent crack growth; reaming method: that is, without affecting the strength of the premise, using reaming method to increase the diameter of fatigue crack, fatigue crack will be removed; scraping repair method: that is, using scraping method: Remove the cracks on the part surface. 3) Increasing the threshold length of fatigue crack: The threshold value of crack growth of metal parts is the maximum stress intensity factor amplitude of non-propagation (stability) of fatigue crack. Its value is usually determined directly by experiments. Chongqing Feilong——water pumps,oil dipsticks,rubber parts and electronic water pumps.
  3. The phenomenon of loss of metal in the relative movement of parts is known as the wear of parts. The occurrence of wear will cause changes in the shape, size and surface properties of the parts, which will gradually reduce the working performance of the parts. Wear is sometimes beneficial, such as running-in. According to different friction principles, wear can be divided into abrasive wear, adhesive wear, fatigue wear and corrosion wear. Then, what is adhesive wear? When the oil film on the metal surface is destroyed, the friction surface is directly contacted with each other, and adhesive wear occurs, which causes the metal on one part surface to transfer to another part surface. It is mainly caused by heavy metal surface and high temperature. Factors affecting adhesive wear: The influence of material properties. Brittle materials are better than plastic materials, and the surface roughness of parts is affected. The higher the smoothness, the smaller the wear volume; the effect of lubricating oil. To ensure sufficient lubricating oil, and to ensure that the viscosity of lubricating oil and working temperature, the surface of the parts of the oxide film is not easy to be destroyed; the impact of movement speed and unit area pressure. The higher the speed of the parts and the greater the load, the easier the adhesive wear is. Chongqing Feilong has a professional R & D team.Welcome to our factory.
  4. Erica Zhu Feilong Jiangli

    Automobile parts failure

    The failure of automobile parts to lose the functions specified in the original design is called failure. Failure refers not only to the complete loss of original functions, but also to functional degradation and serious damage or hidden dangers, continued use will lose reliability and safety components. According to the failure mode, automobile parts can be divided into five categories: wear, fatigue fracture, deformation, corrosion and aging. A part may have several failure modes or failure mechanisms at the same time. There are many reasons for the failure of parts, which can be divided into three aspects: design and manufacture (unreasonable design, improper material selection, improper manufacturing process operation, etc.), working conditions (including the stress state and working environment of parts), and use and maintenance. Feilong Jiangli auto parts has high quality.
  5. Erica Zhu Feilong Jiangli

    New energy vehicle

    Nowadays, new energy vehicles are favored by people. Many large-scale automobile manufacturers have invested a lot of money in the production of new energy vehicles. According to different driving forms, fuel cell vehicles can be divided into pure fuel cell-driven vehicles and hybrid-driven vehicles. Pure fuel cell vehicles are powered by only one fuel cell, which bears all the power loads of the vehicle. Pure fuel cell vehicles have the problems of high cost and high power, which require high dynamic performance and reliability of fuel cell systems, and may not be able to recover braking energy. Hybrid drive electric vehicle is based on fuel cell, adding a group of batteries or supercapacitors as another power source. Feilong Jiangli is constantly innovating and striving to create customer satisfaction auto parts,such as electronic water pumps, rubber engine mount, oil dipsticks and so on.
  6. Erica Zhu Feilong Jiangli

    Auto parts process series-Die forging for parts blank

    The forging method of prefabricating the die chamber with the same shape as the forging piece on the high strength metal forging die so that the blank is pressed and deformed in the die chamber. Characteristics and applications of die forging: (1) higher productivity (2) forging size is accurate and machining allowance is small. (3) forging with complicated shape can be forged. (4) material utilization rate is high. It is mainly used for producing complex forging parts in batch and mass production. Die forging equipment According to the use of equipment, die forging can be divided into hammer die forging and press die forging. The former uses a forging press and the latter is a press. The forging technology on the hammer is good. It is a common die forging method. forging die Forging dies are tools for hot forging. The forging die cavity is made into the corresponding shape which is opposite to the required forging, and is properly typed. The forging blank is heated to the recrystallization temperature of the metal and placed on the forging die. Then the blank is forged into a forging with a flying edge or a minimal flying edge by the pressure of the forging equipment.
  7. Gasoline provides powers to cars. However, have you ever thought about how good or bad gasoline will affect your car? Now, the Feilong Jiang Li, will tell you what harm the inferior gasoline will cause to the car. Firstly, the inferior gasoline will damage the Three-Way Catalytic Converter. Three-way catalytic converter is an external purifying device for automobile exhaust, which can convert harmful gases such as CO, HC and NOx into harmless carbon dioxide, water and nitrogen. The gasoline containing impurities can not be burned sufficiently, will cause exhaust gas is not smooth, a long time will also lead to unqualified tail gas. At the same time, if there are more impurities in the tail gas, it will adhere to the three-way catalytic converter, thus causing damage to the three-way catalytic converter. Secondly, the inferior gasoline will plug the oil circuit. Poor gasoline contains a lot of impurities, so it is easy to plug the oil circuit. When the engine runs, inferior gasoline is full of fuel supply system. The components with small holes or filter function, such as oil pump filter, gasoline filter and fuel nozzle, are easily blocked by impurities in inferior gasoline, which makes the fuel supply not smooth, thus causing the engine to shake, fail to keep up with the oil and stall, or directly unable to start. Thirdly, the inferior gasoline will cause the carbon deposition. Impurities in poor gasoline can not be fully burned and form carbon deposition in the engine cylinder. Even if the impurities pass through the filter, they will silt up in the intake valve, intake port, cylinder, and form a hard deposit for a long time. It has an adsorption effect on gasoline, will cause the mixture thin, affecting the work of the engine. What is more serious is that the colloid sticks to the valve and the piston collides with the unreturned valve when it goes up, resulting in engine damage. A warm reminder of the Feilong Jiangli is that refueling the car of high quality gasoline, to make your car more efficient.
  8. Feilong Jiangli automobile surface drawing parts have the following characteristics: 1.Deformation characteristics The deformation characteristics of large curved surface parts are as follows: the periphery is deep drawing, and the interior has bulging components. The surface shape is supplemented by the exterior material of the pressing surface and the interior by the material extension to meet the bulging requirements. At the same time, due to the deep drawing depth and complex shape, the distribution of deformation parts is uneven. Therefore, controlling the direction and velocity of material is extremely important. The part of large curved surface is easy to wrinkle and crack easily. 2.There must be enough stable blank holder force. Large curved surface parts require not only certain drawing force, but also enough stable blank holder force in the process of drawing. This kind of workpiece is often a large contour size, deep space surface, so the need for deformation and blank holder force are larger. In the ordinary single-action press with air cushion, the blank holder is only about 1/6 of the nominal tonnage, and the blank holder force is not stable, it is difficult to meet the technological requirements of such parts, so in a large number of production, the drawing of such parts are carried out on double-action press. The double-action press has two sliders for drawing and blank-holder, i.e. inner slider and outer slider. The blank-holder force can reach more than 40% - 50% of the total drawing force. It can satisfy the requirement of uneven distribution of deformation around the workpiece, and the blank-holder force is stable, and it is easy to get the deep-drawing parts with better stiffness. 3.The drawing parts must have enough stiffness. Most of these parts are used as the exterior of the machine, requiring sufficient stiffness (no trembling and noise in use) and dimensional stability (to ensure the quality of welding and assembly). This requires that all parts of the material be subjected to uniform tensile stress (ideally a two-way tensile stress state) in the drawing process, and that the tensile stress exceeds the yield limit, but is lower than the strength limit, so that the elastic recovery of the workpiece is reduced to a minimum, so that the shape is not distorted, but also not rupted.
  9. In sheet metal blanking, it is difficult to avoid burrs of varying degrees in general, but improving the workmanship of the parts, improving the stamping conditions, can reduce burrs caused by the following main reasons: (1)Burr can be produced if clearance clearance is too large, too small or uneven. The following factors affect the clearance too large, too small or uneven. a. The manufacturing error of die is not consistent with the parts of a die, and the parallelism of the bottom plate is not good. b.The assembly error of the die is large, the gap between the guide parts is large, and the assembly of the convex and concave die is not concentric. c.Press precision difference as the press guide clearance is too large, the slider bottom and the worktable surface parallelism is not good, or slider stroke and the press table verticality is not good, the worktable rigidity is poor, in punching deflection, can cause gap changes d.Installation errors are as follows: the upper and lower bottom surfaces of the punch die are not cleaned when installed, or the upper die of the large-scale punch is not tightened properly, and the upper and lower die of the punch die is not aligned (especially the non-guide column die) resulting in the inclination of the working part. e.The die structure is unreasonable, the rigidity of the die and working part is not enough, and the blanking force is not balanced. f. The steel plate is large and the steel plate is not smooth. (2)Blunt knife Blunt or gnawing wear can produce burrs. The factors that affect the edge blunt are a.The material and surface treatment state of the die and die are poor, and the wear resistance is poor. b.Die structure is bad and rigidity is bad, resulting in gnawing. c.The operation is not timely lubrication, wear fast. d. Not sharpening the edge of the knife in time. Feilong Jiangli expect to serve you.
  10. Automobile engine is a kind of machine which provides power for automobile, and it is the heart of automobile. It affects the power, economy and environmental protection of automobile. According to different power sources, automotive engines can be divided into diesel engine, gasoline engine, electric vehicle motor and hybrid power. Engine overheating will cause the following hazards to the car: 1) reduce inflation efficiency and reduce engine power. 2) the tendency of early combustion and deflagration increases, resulting in early damage to parts due to additional impact loads. 3) the normal clearance (thermal expansion and cold contraction) of the moving parts is destroyed, the movement block, the wear aggravate, or even damage. 4) the deterioration of lubrication aggravates the friction and wear of parts. 5) the mechanical properties of parts are reduced, resulting in deformation or damage. And if the engine is too cold, it will also do harm to cars. 1) When the temperature of the mixture (or air) entering the cylinder is too low, the quality of the combustible mixture is poor (poor atomization), which makes it difficult to ignite or slow combustion, resulting in a decrease in engine power, an increase in fuel consumption (excessive heat loss, fuel condensation into the crankcase). 2) Water vapor in combustion products easily condenses into water and forms acids with acidic gases, which aggravates the erosion of the body and parts. 3) Unvaporized fuel scouring and diluting the oil film on the surface of parts (cylinder wall, piston, piston ring, etc.), which aggravates the wear of parts. 4) Increased viscosity of lubricating oil, poor fluidity, resulting in poor lubrication, worsening parts wear and power consumption.
  11. The suspension system with adjustable resistance damper adopts air spring with variable stiffness, which can adapt to different road surface and driving style. The working principle of the drag-adjustable shock absorber is that when the load of the vehicle increases, the air pressure in the air bag rises, and the air pressure in the air chamber rises accordingly, so that the diaphragm moves downward to balance the pressure produced by the spring. At the same time, the diaphragm drives the plunger rod and the plunger connected with the diaphragm to move downward, which changes the position of the plunger relative to the throttle orifice on the hollow connecting rod. As a result, the cross-section area of the throttle orifice is reduced, that is, the flow rate of oil through the throttle orifice is reduced, thus increasing the oil flow resistance. On the contrary, when the vehicle load decreases, the plunger moves up and the cross-section area of the throttle orifice is enlarged, thus reducing the flow resistance of the oil. Therefore, the resistance of the shock absorber is changed with the change of vehicle load.
  12. In order to accelerate the vibration attenuation of the frame and body and improve the ride comfort of the vehicle, vibration absorbers are installed in the suspension system of most automobiles. Both the shock absorber and the elastic element are installed in parallel. Hydraulic shock absorbers are widely used in vehicle suspension systems. The principle of the hydraulic shock absorber is that the oil in the shock absorber shell flows repeatedly from one cavity to another through some narrow cavities when the piston moves in the cylinder cylinder when the driver and the bridge move reciprocating relative to each other. At this time, the friction between the hole wall and the oil and the internal friction of the liquid molecule form a damping force to the vibration, so that the vibration energy of the body and the frame is converted into heat energy, which is absorbed by the oil and shock absorber shell, and then emitted into the air. The damping force of the shock absorber increases or decreases with the relative velocity of the frame and the axle, and is related to the viscosity of the oil. Therefore, it is required that the viscosity of the oil used in the shock absorber should be as little as possible affected by the temperature change, and has the properties of anti-vaporization, anti-oxidation and non-corrosion to various metal and non-metal parts.
  13. Erica Zhu Feilong Jiangli

    Impeller for water pump

    Due to the limitation of installation space and performance requirement, automobile engine cooling water pump has the characteristics of small volume, simple manufacture, and is conducive to mass production. The cooling water pump is usually made up of main parts such as pump body, impeller, shaft, bearing, water seal and pulley. According to the different structure of the engine cylinder block, the pump pressurized water chamber can be integrated on the engine cylinder block, and the impeller can also be separately configured as the core functional components of the pump, its diameter, outlet width, blade structure shape and other parameters and structure design directly determine the performance of the cooling water pump. There are many kinds of cooling water pump structure, according to the impeller material is different, can be divided into cast iron impeller, stamping impeller and plastic impeller; according to the impeller has no cover plate can be divided into open impeller and closed impeller; according to the impeller blade shape is different, can be divided into straight blade impeller, single curvature blade impeller and space twisted blade impeller. With the development of science and technology, cast iron impellers are still used in the cooling water pumps of trucks, buses and other heavy-duty vehicles and a few self-owned passenger cars. Pressed impellers are mostly used in Japanese passenger cars, plastic impellers are mostly used in European and American advanced countries, and three kinds of impellers are used in domestic self-owned brand cars, but with With the introduction of new technology from abroad, plastic impellers have been used in newly developed machines. When cooling water pumps work, the coolant rotates with the impeller on the one hand, and flows out of the rotating impeller on the other.
  14. Today, we learn the fourth categories of automotive rubber products: Belt products. Belt products are mainly used in automobiles to transfer torque power and speed, power from the power source engine to the need for power systems and places. It is installed in cooling fan, cooling water pump, brake compressor, booster pump, air conditioning system and steering system. The car belt is mainly V belt. Usually there are three kinds, that is, wrapped V belt, cutting V and multi wedge belt to cut W belt. Cutting V-belt has no coating on both sides, good flexibility, friction coefficient, with a large force, high linear speed, heat dissipation and fatigue resistance and energy-saving characteristics, commonly used rubber MIBR and R. Synchronous toothed joint is used for valve ignition of automotive engines. Its operating conditions are high speed, high power and high temperature.
  15. (1) its unique properties are high elasticity. An object can be shaped by an external force, which is the most obvious manifestation of the deformation. This highly valuable rubber elasticity is not found in any other engineering material. (2) It has a certain mechanical strength and has the ability to relax impact and absorb vibration. (3) Excellent properties such as abrasion resistance, insulation, impervious and airtight. (4) Some special synthetic rubber also has the characteristics of oil resistance, corrosion resistance, heat resistance, cold resistance, fire resistance, aging resistance, radiation resistance and so on. Rubber is divided into natural rubber and synthetic rubber according to raw materials. It is divided into general oak and special oak according to application. The common types of rubber used in automobiles are natural rubber, styrene-butadiene rubber, chloroprene rubber, nitrile-butadiene rubber, EPDM, acrylate rubber, fluorine rubber, silicone rubber, polyurethane rubber and butyl rubber.
×