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袁春凤 (Tiffany)

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Everything posted by 袁春凤 (Tiffany)

  1. Inspection rules for rubber parts for automobiles 1.rubber hardness Test method of indentation hardness based on GBT531.1-2008 rubber pocket hardness tester contents and requirements Instruments and equipment: Shahr hardness tester (type A, D) Environmental conditions: the laboratory temperature is 23 C + + 2 C, the relative humidity is 60%~70231 Test method: the specimen thickness is at least 6mm. If the thickness of the sample is less than 6 mm, it can be stacked with no more than 3 layers of smooth, parallel samples with each layer thickness not less than 2 mm. The specimen must have enough area to make the needle and specimen contact position at least 12mm from the edge. Place the specimen on a solid plane, hold the hardness tester, press the pin at least mm from the edge of the specimen, press the pin smoothly on the specimen, and read it within 3 seconds after the full contact of the pin with the specimen. Results: the hardness values were measured 5 times at different locations of 6mm, and the median was taken. Feilong Jiangli will update the more inspection rules for automobile rubber parts
  2. Rubber shock absorber for automobiles With the development of social economy, the automobile industry at home and abroad is facing a period of rapid change, which is characterized by further improving the service life of the automobile under the premise of ensuring driving safety, riding comfort, high speed and luxury. Damping products are used to control the vibration and noise of automobiles and to improve their handling stability. They are generally placed in the engine frame, rod holder, suspension shaft lining, center bearing bracket, bump limiter and torsional vibration absorber to improve the safety and comfort of automobiles. Damping products can be divided into four categories: bracket type, shaft lining type, buffer type and damping type. The main requirements of damping, heat resistance and fatigue resistance are good. Automobile shock absorber rubber products include engine bearings, suspension components, rubber springs, rubber air springs and impact rubber protective parts. In recent years, in order to improve the safety, comfort and maneuverability of automobiles, the variety and quantity of shock absorber rubber products for automobiles are increasing as the number of shock absorber rubber products on a car has reached 50-60 pieces.
  3. 5 rubber materials for shock absorption purposes NR.SBR.BR is a common citrus material: NBR for oil-resistant vulcanizates; CR for weather-resistant vulcanizates: IR for high damping vulcanizates; EPR for heat-resistant vulcanizates. NR has excellent elasticity, good resistance to fatigue and aromatics, low tart and creep, good cold resistance, electrical insulation and workability. Therefore, NR is widely used as shock absorber in order to meet the requirements of low temperature or weather resistance, and can be modified with BR or CR. The shock absorber made of NR, BR and metal salts containing organic acid containing one OH group with more than 4 carbon atoms has good durability. The compression permanent deformation at 70Cx22h and 40Cx148h is 17.0% and 11.7% respectively. EPDM has attracted much attention in recent years due to its excellent weather resistance, ozone aging resistance, electrical insulation, heat resistance and cold resistance. Recently, Mitsui Chemical Co. and Kwannukawa Rubber Co. developed a new type of heat-resistant and shock-absorbing rubber material by using high molecular weight EIM and low molecular weight EHIM, and obtained a Japanese patent. The test results show that the damping property of the rubber is the same as that of NR, but its heat resistance and low temperature softness are better than that of other rubber such as NR. "The rubber material made of EDM for shock absorbers on automotive parts has very good heat resistance. After 190C *5 aging, the material still has very good interlaminar adhesion. Silicone rubber R or halogenated IR can be used when high damping is required; U has excellent wear resistance, flexibility resistance and resistance to hydrocarbon fuels and most organic solvents, as well as high physical properties, good electrical insulation, adhesion and aging resistance. . U has also been widely used in shock absorption and sound insulation, such as Adachi, etc. The rubber sheet with good shock absorption and sound insulation is made by U. The effect is good when it is applied to floor, ceiling and bending plate. Feilong jiangli could supply best quality rubber parts for car body parts.
  4. Hydrogen induced wear: hydrogen is released during the friction due to mechanical and chemical action. Hydrogen diffuses into the deformed layer of metal surface, causing a large number of crack sources in the deformed layer. The generation and development of cracks make the surface material fall off, which is called hydrogen-induced wear. Oxygen may come from material itself or environmental medium, such as lubricating oil and water.
  5. The mechanism of cavitation is surface fatigue damage caused by impact force, but the chemical and electrochemical action of liquid and abrasive inclusion in liquid may accelerate cavitation damage. For example, the cylinder liner cavitation is caused by the action of piston lateral thrust because the combustion pressure in cylinder varies with crankshaft angle. The elastic deformation and high-frequency vibration of bubbles produce great impact force (tens or even tens of thousands of high pressure) and high temperature (hundreds of degrees) at the instant of collapse, and the collapse speed can reach 250m/s. Feilong jiangli will update analysis of more auto parts failure models.
  6. Perfect match of pump and thermostat The engine is realized by the circulation of coolant. The component of the forced circulation of coolant is a water pump, which is driven by a crankshaft belt to promote the circulation of coolant throughout the system. Specializing in the production of water pumps for 40 years Feilongjiang Li's latest product - electric water pumps, it can accurately control the pump speed, and effectively reduce the loss of output power. The cooling of these coolants on the engine should be adjusted at any time according to the working conditions of the engine. When the engine temperature is low, the coolant circulates inside the engine itself. When the engine temperature is high, the coolant circulates between the engine and the radiator. The thermostat is used to control the coolant in different cycles. The thermostat can be regarded as a valve, its principle is to use materials that can be flexible with the temperature (paraffin or ether and so on) as a switch valve, when the water temperature is high material expansion top open valve, coolant for a large cycle, when the water temperature is low material shrinkage closed valve, coolant small cycle.
  7. What is an automobile shock absorber? 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.
  8. Automotive engine bracket Automobile engine bracket is a safe and functional part of powertrain mounting system. It must satisfy the strength of automobile under various driving conditions and the restraint mode of mounting bracket has a great influence on the noise inside the vehicle. If the design is unreasonable, the natural frequency of the mounting bracket I is too low and in the range of engine operating speed, the mounting bracket will produce resonance, which will increase the noise inside the vehicle. Therefore, modal is one of the important design indexes of mounting bracket. Taking the four-cylinder engine of passenger car as an example, according to the resonance theory, it is required that the natural frequency of the engine mounting bracket should be greater than 500 Hz, and the lowest should be greater than 400 Hz. In fact, due to the limitation of the layout space, the above requirements can not be met. The first order natural frequency should be increased as much as possible. Feilong Jiangli,40 years specialize in engine bracket, through the optimization design and modal analysis of the suspension bracket practice, summed up to improve the modal method, to provide a theoretical basis for design.
  9. Shock absorber 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 point, the friction between the hole wall and the oil and the friction between the liquid molecules form a damping force to the vibration, so that the vibration energy of the body and the frame can be converted into heat energy, which is absorbed by the oil and shock absorber shell, and then dispersed 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, the viscosity of the oil used in the shock absorber is required to be as little as possible affected by temperature changes: and has the properties of anti-vaporization, anti-oxidation and non-corrosive to various metal and non-metal parts.
  10. The phenomenon that two objects move relative to each other to produce motion resistance between their contact surfaces is called friction, which is called friction. The existence of friction not only increases the power consumption, but also causes the wear of parts' contact surfaces. Therefore, lubricating oil is usually used between the relative moving surfaces of automobile parts to reduce friction. Failure of automotive parts 75% is caused by friction. Friction can be divided into dry friction, liquid friction, boundary friction and mixed friction according to the lubrication state of the parts. (1) dry friction The friction between the frictional surfaces without any lubricating medium is called dry friction. When the parts are in the state of dry friction, the surface of the parts is abraded sharply, so the surface of the moving parts of the automobile should avoid the occurrence of dry friction as far as possible. Dry friction and boundary friction are the main friction between the upper part of cylinder wall and piston ring. Dry friction will occur when the journal and bearing are subjected to impact load in the working process. (2) liquid friction Two the friction of the friction surface when the lubricant is completely separated is called liquid friction. In liquid friction, the two friction surfaces are completely separated by a layer of lubricating oil film with a thickness of 1.5-2.0um, which avoids direct contact between the working surfaces of the two parts. Friction only occurs between the lubricating fluid molecules, so the friction resistance is very small, and the wear of the parts is very slight. Most of the relative motion parts of a car are carried out under the condition of liquid friction (for example, crankshaft and bearing). (3) boundary friction Two friction surface separated by a very thin boundary film is called boundary friction. The oil film thickness is usually below 0.1um. Friction only occurs between the outer molecules of the boundary film, reducing the friction and wear of the parts. But its thickness is very small, and it is easy to be destroyed by impact and high temperature, so it is not as reliable as liquid friction. For example: between cylinder wall and piston ring; if the work crankshaft and journal between the insufficient supply of lubricant, easy to produce boundary friction. (4) Mixed friction The friction between two friction surfaces in the presence of dry friction, liquid friction and boundary friction is called mixed friction. In the actual working state, the parts usually work under the mixed friction state, and the friction state varies with the working conditions.
  11. The stamping process can be divided into different classes according to different standards. (1) according to the different deformation properties, it can be divided into separation process and forming process. Separation process: the material is processed under external force to produce deformation, as used in the deformation part of the equivalent stress reached the shear strength of the material, the material will produce shear cracking and separation, thus forming a certain shape and size of the parts. These stamping processes are generally referred to as separation processes, such as tailoring, punching, blanking, and cutting. Forming process: under the action of external force, the equivalent stress acting on the deformed part of the material is between the yield limit and the strength limit of the material. The material only produces plastic deformation, so as to obtain a certain shape and size of the parts. These stamping processes are collectively called forming processes, such as bending, drawing, forming and other deformation processes. (2) according to the basic deformation mode, it can be divided into blanking, bending, drawing and forming. Punching: Punching, such as punching, blanking, etc., is a process in which materials are cut apart along closed or non-closed contours. Bending: The stamping process of bending a material into an angle or shape is called bending, such as bending, crimping, twisting, etc. Drawing: The process of drawing a flat blank into a hollow part, or further changing the shape and size of the hollow part with a drawing die, is called drawing. There are thinner drawing and thinner drawing. Forming: The stamping process that causes material to deform locally to change the shape of a part or blank is called forming, such as flanging, shrinkage, etc.
  12. Free forging Definition of free forging Free forging is the use of impact force or pressure on the metal between the top and bottom of the anvil free form in all directions, without any restrictions to obtain the desired shape, size and certain mechanical properties of the forging method. Free forging equipment The equipment of free forging can be divided into two categories: forging hammer and hydraulic press. The hammer used in production is air hammer and steam air hammer. Hydraulic press is the only way to produce large forgings by using static pressure generated by liquid to deform the blank. Basic process of free forging Rough upsetting is a forging process which makes the cross section of billet larger and the height smaller. There are two kinds of upsetting: integral upsetting and partial upsetting. Drawing and drawing is the opposite of upsetting. It is a forging process to increase the length of the billet and reduce the cross section. The punching process of punching holes or blind holes on billets is called punching. The characteristics of free forging and the application of free forging depend on manual operation to control the shape and size of forgings. Therefore, the forgings have low precision, large machining allowance, high labor intensity and low productivity. Therefore, it is mainly used in single-piece and small-batch production with simple structure and shape of forgings.
  13. Forging process foundation Forging concept Forging is a kind of forging method that produces partial or total plastic deformation of billet or ingot under the action of pressure equipment and tools to obtain certain geometry, size and quality. Forging methods: free forging, die forging, die forging, rolling, drawing, extrusion and so on. Among them, free forging and die forging are the most commonly used forging methods. Characteristics and application of forging Improve the internal structure of metal and improve the mechanical properties of metal. Besides free forging, it has higher labor productivity. Save metal materials. It is difficult to forge workpieces with complex shape and inner cavity. Forging is generally used in the manufacture of high strength, good reliability of automotive parts, such as: engine crankshaft, camshaft, connecting rod, chassis drive shaft, cross shaft, front axle, rear axle, steering system knuckle, steering knuckle arm.
  14. Melt mold casting One is to make the wax into a mold, coat it with several layers of refractory paint to make a mold shell, and then heat the mold, so that the mold melt, flow out, and baked into a certain strength mold, and then poured, shell and get a casting method. Process features: take the melting pattern as the starting mode. The precision of casting is high, and it is a method of little cutting. Its equipment is simple and production quantity is not restricted. It is mainly used for mass production and mass production. The drawback is that the process is complex and the production cycle is long. Pressure casting - a casting process in which molten metal is rapidly pressed into the cavity of a metal mold under high pressure and solidified under pressure to obtain a casting. Process characteristics: High speed and high pressure were added to the metal mold casting to enhance the metal fluidity, which was mainly used in the batch production of non-ferrous alloy (such as aluminum, copper, magnesium, etc.) precision castings. Centrifugal casting - a casting process in which molten metal is poured into a high-speed rotating mold to solidify liquid metal under centrifugal force to obtain a casting. Process features: compact structure, good casting quality. It is used to produce hollow castings.
  15. Basic knowledge of shock absorbing rubber products 1. Static stiffness: refers to the ratio of the change of pressure (or tensile force) to the change of displacement in a given displacement range. The static stiffness must be measured within a certain displacement range. The static stiffness values measured in different displacement ranges are different, but some families require the change curve measured in the whole displacement range. 2. Dynamic stiffness: It refers to the ratio of the change of pressure (or tensile force) to the change of displacement of damping rubber in a certain displacement range and a certain frequency. 3. dynamic magnification: the ratio of the dynamic stiffness to the static stiffness measured by the damping rubber in a certain range of displacement. 4. Loss coefficient: There is a phase difference between the deformation of rubber and the stress of rubber in the course of the force acting on damping rubber, and the stress of rubber is generally ahead of the phase angle of the deformation of rubber. 5. Torsional stiffness: refers to the ratio of torsional moment to torsional angle of damping rubber within a certain range of torsional angle. 6. Durability: It refers to the number of times of vibration when the rubber is in good condition after n times of reciprocating vibration under certain preloading load, amplitude and vibration frequency in a certain direction.Thanks for the help and support of Chongqing Feilong Jiangli Auto Parts technical department.
  16. Fatigue life prediction of rubber bushing in vehicle system 1.Response analysis of rubber bushing under random excitation The Monte Carlo method is used to simulate the random excitation spectrum. 2. The fatigue life calculation of rubber bushing under random load can calculate the maximum strain energy density of rubber bushing under different excitation by using the response characteristics of rubber bushing under engine and road excitation obtained previously. The fatigue life of rubber bushing can be calculated under different load conditions. The maximum strain energy density U = 0.5134Nmm2 and the fatigue life N = 771371 were predicted under the excitation of engine speed n = 3000r/min and class B pavement, while U = 0.6893Nmm2, N, = 146774 under the excitation of engine speed n = 3000/min and class D pavement.(Thanks for the help and support of Chongqing Feilong Jiangli Auto Parts technical department.) 3. The test verification of the front sub-frame module is expensive because of the fatigue test of the whole vehicle system. Now the former sub-frame module is the research object, and the calculation results are compared with the test results. The front sub-frame is installed in accordance with its layout in the vehicle, and the six points connected with the body on the sub-frame are restrained. Sinusoidal excitation is carried out at the midpoint of the rear beam, and the maximum frequency which can be reached under the condition of satisfying the amplitude of the force is taken as the test frequency. The amplitude of force is 2.45.2kN. Fatigue failure criteria of rubber bushing: 2mm crack (equivalent to 20% of tensile coefficient).
  17. Structural form of engine suspension mount In the design of engine mount, the purpose of mount, such as the quality of support and limited displacement, must be fully considered, and the reasonable shape must be chosen. There are three basic types of mounting: compression, shearing and tilting (see figure below).(Thanks for the help and support of Chongqing Feilong Jiangli Auto Parts technical department) If the displacement of the power assembly is too large, the total power cost will be caused, or the intake and exhaust system, control mechanism, pipeline, wiring and other peripheral parts will be damaged. At the same time, the mounting cushion is easy to damage. For this reason, suspension stiffness must be limited from overhanging structure 1, plus larger displacement. For example, when a car is accelerating or turning, the inertia force generated by the power assembly may cause a greater displacement of the power assembly. In order to limit the displacement of power assembly, it is necessary to design rigid suspension, that is, large stiffness suspension cushion 2, nonlinear and variable stiffness suspension structure, in order to reduce the vibration caused by small exciting force and limit the large vibration displacement when large exciting force. For example, the engine output torque is small when the car stops idling, or when the car runs at a constant speed. At this time, the lower stiffness of the suspended cushion should be designed to effectively isolate vibration. But in the fast start, the reaction force of the driving torque is very large, which can make the power assembly produce greater vibration. In addition, when the vehicle is running on uneven road surface, with the large ups and downs of the whole vehicle, the dynamic assembly also produces great up and down inertia. At this time, the stiffness of the suspension cushion is increased, which can effectively limit the vibration and position of the power assembly. Shift
  18. The number of mounting points depends on the length, mass, use and installation of the power assembly. The mounting system can be mounted at 3, 4 and 5 points. Generally, three-point and four-point mounting systems are used in automobiles, because if the number of mounting points increases when the vibration is relatively large, when the body deformation, some mounting points will be dislocated, so that the engine or mounting bracket force is too large and cause damage to the three points, the advantages of the support is that no matter how bumpy and jumping the car, it can always ensure the support. The point is in a plane, which greatly improves the force condition of the body. The front and rear suspensions of the four-point mount are mainly used to prevent the torsion of the power assembly, and the torsional stiffness is larger than that of the three-point mount. Three point mounting system Left suspension: connect with gearbox, mainly power assembly limit and supporting function. The right suspension: connected with the engine, it can isolate the engine, such as vibration, inertia force and vibration. Rear suspension: It is connected with the gearbox, and has the functions of longitudinal limit, bearing torque, driving condition limit and so on. Four point mounting system It can overcome the large torsional reaction force, but the torsion stiffness is large, which is not conducive to the isolation of low frequency vibration. Left and right suspension: close to the torsional inertia axis, support the powertrain up and down, and have the function of vibration decoupling. Front and rear suspension: with the transmission, it has longitudinal limit, driving condition limit and torque endurance.
  19. Introduction of defects in rubber products vulcanizing 1.Lack of glue: due to insufficient weight or poor fluidity, some defects should be found in rubber parts. 2.Degumming: the failure of rubber and frame inserts will result in disengagement or separation. 3.Bubbles: also known as "bulging", because the gas is coated in the rubber epidermis and the formation of local epidermis blistering phenomenon; Thanks for the help and support of Chongqing Feilong jiangli’s Technical department. 4.Rotten bubbles: also known as "pit gas", because the gas has not been discharged from the cavity, so that the die corner of the rubber cavity is less sulfur sticky, and protruding from the surrounding rubber surface phenomenon 5.Gel cracking: a phenomenon of cracking on the glue surface. 6.Under sulfur: the inner surface of the gum is microporous, and the exterior is uplifted and deformed. 7.Sticking mould: the phenomenon that the local glue of vulcanized product is adhered to the wall of the mold cavity. 8.Hot die: also known as curling edge, "bite edge" and so on, refers to the product parting line is not smooth, cracks, serrated waste edge and other phenomena.
  20. Car with 3-5 years, the following 7 rubber parts must be checked and replaced. 1.Engine foot glue The purpose of the engine foot glue is to isolate the engine vibration from the cockpit and fix the engine foot and frame with rubber pads, so as to achieve a certain damping effect and make the engine work smoothly. Usually the engine is oxidized when the driving distance exceeds 50,000 kilometers or the driving time exceeds 5 years. The elastic corpse reduces the damping effect of the engine and can not effectively isolate the vibration of the engine from the frame so that the vehicle leaves the vehicle. Now the boom is loud, but it's fast or abnormal. Many toll collectors often overlook this problem, when the engine appears, think about it, first check the engine itself, but ignore the foot glue oxidation. Replacing the foot glue is not complicated, to the roadside general automobile repair shop can be replaced, the cost is only a few hundred dollars, you can solve the car engine abnormal sound idle jitters problem. 2.Suspension swing arm rubber bearing The suspension swing arm rubber bearings are common in the McPherson front suspension which is now used in driving vehicles. Because of its mechanical characteristics, rubber bearings are needed to cushion and limit vibration and play a supporting role. Many consumers are very strange to suspension swing arm rubber bearings, because it is possible to love the car will not be replaced, but it does affect our car driving experience. Thanks for the help and support of Chongqing Feilong jiangli’s Technical department.Many consumers will feel that after a few years old cars are no longer as easy to drive as new cars, suspension jump response is not very sensitive, and even the road conditions are not very good road surface, the body will jump very seriously, steering at high speed and the stability of the vehicle at high speed is reduced, these are the impact of aging suspension brackets. Replacing the rubber bracket of the suspension arm requires the use of a professional lift, so consumers had better go to a professional body for replacement. 3.Shockproof top rubber bearing The rubber bearing of the shock absorber roof is a cushioning mechanism which can alleviate the vibration of the suspension when the suspension jumps and transmit to the fulcrum of the frame. The early rising part of the vehicle, the inverted suspension is fixed and manufactured. Instead, it uses insomnia so that the body can be used only after the stability of the road surface is reduced. The rubber is used as the material of manufacture, but the design life is five years left. Right. Vehicles passing through the bumpy road caused by suspension ministries to issue abnormal sound, or suspension jump ten people response, not very sensitive, usually suspension too much vibration, resulting in a reduced sense of carriage ride. 4.Crankcase rear oil seal Crankcase oil leakage is a problem many owners will encounter, especially in the use of several years of old cars, crankcase oil leakage let many owners are very distressed. Usually the main reasons for oil leakage of crankcase are: first, there is no use of professional lubricant seal in the manufacturing process, in the use of the process of vibration displacement caused by oil leakage. Secondly, because of the engine oil seal design problems, the use of a period of time after the force caused the deformation of the oil seal groove, and ultimately oil leakage. The above two are the quality problems of the manufacturer, but after more than five years of engine life, crankcase tank with aging aggravated, will produce small cracks, will also lead to oil leakage. 5.Drive shaft damping rubber For some rear-drive and four-drive vehicles after several years of use will encounter the need to replace the transmission rubber shock absorber, the replacement of shock absorber rubber is very time-consuming, labor-consuming, very high, but if not replaced in time will cause permanent deformation damage to the transmission shaft, causing resonance in the front and rear transmission of the car, affecting the line. The car is safe. In our normal driving process, the transmission shaft vibrates with the body and this traditional process is not smooth, so the need for such damping rubber to prevent the transmission shaft should be centralized vertical damage, so the transmission shaft needs transmission rubber shock absorption. 6.Frame sealing strip The replacement of the frame sealing strip is also a problem that many car owners will ignore. The frame sealing strip is pressed on the special rail groove by external force. Exposed to oxidation outside the car, the sealing of the car body will decrease. The infiltrated rain will penetrate into the car body through the crack. The acid rain will corrode the car body inside, and eventually lead to the corrosion. The rust inside the car body is very difficult to deal with. The strength of the car body gradually decreases, and eventually the car body may be rusted through. Therefore, changing the frame seal strip in time is one of the main measures to protect the body from rust. 7.Rubber hose for engine oil circuit The oil pipeline of the engine needs to withstand the high temperature and pressure of the engine, so the consequences are very dangerous once it aging and finally ruptures. Usually the service life of the engine input pipeline is about four years, and cracks will appear on the surface of the aging pipeline as time goes on, which is very easy to spontaneous combustion in the high temperature environment of the engine compartment. Once the driver smells a smell of gasoline through the air conditioner, he must be on the alert.
  21. thermostat 1) Function: Change the circulation route and flow rate of cooling water, automatically adjust the cooling intensity, so that the temperature of cooling water is often maintained at 80 to 90 degrees 2) the installation position is installed in the passage of cooling water circulation, usually installed in the outlet of the cylinder head. 3) form: divided into wax type and foldable type. The wax thermostat is equipped with paraffin wax in the space between the rubber tube and the inductor. In order to improve the thermal conductivity, paraffin wax is often mixed with copper or aluminum powder. At normal temperature, paraffin wax is present and the valve is pressed on the valve seat. At this point the valve closes the water path to the radiator, cooling water from the engine cylinder head outlet, through the pump flow back to the cylinder block water jacket for small circulation. When the water temperature of the engine rises, the paraffin wax becomes liquid gradually, and the volume increases accordingly, forcing the rubber tube to shrink, thus producing upward thrust on the upper end of the thrust rod. The upper end of the reversing rod is fixed, so the reversing rod produces a downward reverse thrust on the rubber pipe and the inductor, and the valve opens. When the water temperature of the engine reaches above 80, the valve opens completely, and the cooling water from the outlet of the cylinder head flows to the radiator for large circulation. FAW Audi 100 cars and CA1091 trucks are all made of wax type thermostat. The folding thermostat is made of an elastic, folding, airtight cylinder (made of brass) with a volatile ether inside. The main valve and side valve move up and down with the upper end of the expansion cylinder. The vapor pressure of the liquid in the expansion cylinder varies with the ambient temperature, so the height of the cylinder varies with the temperature. When the engine works under normal thermal condition, that is, the water temperature is higher than 80 C, the cooling water should all flow through the radiator, forming a large cycle. At this point the main valve of the thermostat is fully opened, while the side valve closes the bypass hole completely: when the cooling water temperature is lower than 70 degrees Celsius, the steam pressure in the expansion cylinder is very small, so that the cylinder shrinks to the minimum height. The main valve is pressed on the valve seat, that is, the main valve is closed and the side valve is opened. At this time, the water path from the water jacket to the radiator is cut off. The water in the water jacket can only flow out of the by-pass hole into the pump through the by-pass pipe, and then is pressed into the engine water jacket by the pump. At this time, the cooling water does not flow through the radiator, but follows the water jacket and the pump. Ring, so as to prevent the engine from overcooling, and make the engine hot quickly and evenly: when the engine cooling water temperature in the range of 70-80, the main valve and side valve in the semi-open and closed state, at this time part of the water for large circulation, while the other part of the water for small circulation.Thanks for the help of the Chongqing Feilong Jiangli Auto Parts’ Technical dept. 1) When the cooling water temperature is lower than 76 degrees, the main valve of the thermostat is closed, and the sub-valve opens the cooling water to circulate in a small range between the pump and the water jacket, so that the water temperature rises rapidly. When the water temperature is higher than 86 degrees, the main valve of the thermostat is fully open, the secondary valve is fully closed, and the cooling water flows through the radiator for water circulation to keep the engine at normal working temperature.
  22. Rubber bushing is mainly used in the position of automobile front and rear suspension and other frequent vibration. It plays a vital role in the whole vehicle NVH (Noise Vibration Harshness), and it will be invalid and will affect the whole vehicle noise and driving stability. The failure mode of rubber bushing is not only its own quality control, but also its working environment is one of the key factors affecting its life. Thanks for the support of the Feilong Jiangli technical department. Automobile suspension is a component that connects the frame (or body) with the axle (or direct and wheel). Its main functions are: D mitigates and inhibits vibration or shock caused by uneven pavement to ensure the car has good smoothness; 2 (2) rapidly attenuates the vibration of the body and axle (or wheel); 3 (3) transfer function in the wheel and frame (car) Various forces (vertical force, longitudinal force, transverse force) and moments (braking moment and reaction moment) between the body; 4) to ensure the necessary stability of the vehicle.
  23. The measuring rod part of the oil gauge The measuring rod part of the oil gauge generally has three structures: steel wire, steel belt (Bian Chi), and many winding wires. Among them, spring steel wire is commonly used in steel wire structure, and the material is hard, which is suitable for the relatively slow bending ruler tube. The multi strand wire is easy to insert and plugged in the bending scale tube, but the price is higher. The material of flat ruler generally chooses 0.8mm~1.2mm stainless steel strip, and the price is relatively low. As the core part of the ruler, the head of a ruler is the most important part of the ruler. In the drawing, it is easy to rub with the ruler tube that matches with it. The particles produced by the friction will fall into the lubricating oil. The unclean lubricating oil will cause great wear to the bearings of the engine. In the indicator part of the scale, the head can be designed as a roller structure, which is not only effective. The scale has reduced the tube pulling force of the ruler and reduced the scraping of the ruler head and the ruler tube. For the oil gauge with steel strip structure, in order to make the gauge clearly indicate the position of the liquid level, it is easier for users to read the oil gauge. Generally, the head of the flat ruler is treated with sand blasting or press mesh, and some rhombic pits can be set on the head of the plastic. These pits are disconnected from each other, so that the oil can climb up the trough under the siphon effect, which affects the accurate reading of the scale.
  24. 1. structure of Brushless DC water pump The water pump used in the car is higher than the ordinary water pump in the structure and performance requirements: the working environment of the motor pump is poor, it should be able to prevent vibration, moisture-proof, heat resistant, especially for the stability of the pump, and the reliability of the water pump has higher requirements for the magnet rotor of the brushless DC centrifugal pump and the impeller. The rotor is in the middle of the rotor. The shaft sleeve is the direct injection molding shaft sleeve. The shaft sleeve is fixed in the rotor body with high endurance grinding graphite. The stator and the circuit board part of the motor are sealed in the pump body with epoxy resin adhesive. The stator and the rotor are a cavity. The pump cavity is connected with the rotor cavity of the motor. The rotor cavity of the motor is completely isolated from the motor stator and motor control. The rotating shaft is the rotating shaft. With high smooth, high strength zirconia finish, the shaft connects the motor with the pump body, without the traditional mechanical shaft seal, so it is completely sealed and the torque of the leakproof motor is produced by the magnetic field of the coil on the sand steel sheet (stator) to drive the permanent magnetic magnetic iron (rotor) to work. N (n is even) order magnetization of a magnet makes the parts of the magnet form a fully coupled magnetic system. When the magnetic pole produced by the stator coil is opposite to the magnetic pole of the magnet, that is, the displacement angle between the two poles is the lowest than that of the time magnetic system; when the magnetic pole rotates to the same pole, that is,The displacement angle between the two poles is 2 T / n, and the magnetic energy of the magnetic system is the maximum. After removing the external force, the magnetic poles of the magnetic system repel each other, and the magnetic force will restore the magnet to the lowest state of magnetic energy. So the magnet produces motion to drive the rotor rotation: the driving force of the brushless pump impeller is the brushless motor brushless DC pump through the electronic commutation, without the use of carbon brush, the magnet rotor and the stator sand steel sheet all have multilevel magnetic field, and the rotor will automatically change the direction of the magnetic pole when the rotor is rotated relative to the stator, so that the rotor is always kept in the same direction. It makes the stator and rotor of the brushless DC centrifugal motor pump completely isolated and completely avoids the liquid leakage of the traditional brushless DC pump. And it can be fully dive and completely waterproof, effectively improving the service life and performance of the pump, so the brushless does not need the lubricating grease of the pump bearing, and there is no seal pad and oil seal. 2. the brushed DC motor pump has a brushed DC motor pump, and the bearing of the pump shaft is lubricated by grease. Therefore, it is necessary to prevent the leakage of the coolant to the lubricating grease and prevent the leakage of the coolant. Water seal and gasket are used to prevent leakage of water pump. The water seal ring and shaft are fitted between the impeller and the bearing through interference, and the water seal static seal is tightly leaned to the shell of the pump, so as to achieve the purpose of sealing the cooling fluid, the magnet of the brushed DC centrifugal pump and the impeller are injected into the rotor of the motor. There are direct injection molding axle bushes in the middle of the rotor, through the high performance pottery. The ceramic shaft is fixed in the shell. The stator of the motor and some meter of the circuit board are sealed in the pump body with epoxy resin glue. There is a thin wall between the stator and the rotor, and it is completely sealed without the traditional mechanical shaft seal. The torque of the motor is through the coil on the sand steel sheet (stator) to generate magnetic field to drive the permanent magnet (rotor) to work. Its electromagnetic working principle is the same as the brushless pump motor. In short: brushless pump electronics commutation: brush pump motor is mechanical commutation: brush pump impeller drive is brush motor. Thanks for the help of the Chongqing Feilong Jiangli Auto Parts’ Technical deptAnd welcome to share the idea with us. Thanks https://s1.ax1x.com/2018/07/21/P8cDzV.jpg
  25. (1) When the water pump is installed, the water seal seating assembly is not installed in place, causing the pump to continue to leak. There will also be a variety of reasons leading to the decrease of the front headlight illumination or the effect of the radiator. When the water seal is leaking, the cooling water is thrown out and dripping from the inspection hole of the pump when the pump shaft meets the retaining ring. In addition to the maintenance supplies, such as the spare tire, Jack, the tyre wrench and so on before the road, the pump does not pay attention to the pump when the retaining ring is changed. The body and the pump cover can not be well connected and sealed. (2) the machinery is old and old, the wear, corrosion and aging of the machine parts in the water seal, so when the engineering machinery has long been suspended, there is no cooling water in the engine, it can deal with the metabolites accumulated in the human body as soon as possible, which will cause a small amount of leakage. In addition, there are some "penetrating night" night vision instruments in the market, and the bakelite seal mat and cast iron bushing have not been fully ground. It will also lead to a small amount of water leaking in the water pump, which can easily cause the uneven wear of the bakelite gasket and the lining face: the spring is soaked in the water for a long time. The road conditions of 5-200 meters or even 500 meters were clearly observed. (3) forget to let water or release water in winter, and the temperature is too high when the water is released. Before leaving the car, we must carefully check the headlights, taillights, steering lights and brake lights, all of which may cause the water pump body to be frozen to cause leakage. Thanks for the help of the Chongqing Feilong Jiangli Auto Parts’ Technical dept And welcome to share the idea with us. Thanks https://s1.ax1x.com/2018/07/21/P8cDzV.jpg

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