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When the vehicle is driving on a daily basis, the tires and wheels cannot avoid being bumped. Since most of the wheel rims are made of aluminum alloy, if the vehicle is driving at a high speed, the wheel rim may be damaged by the stones on the road, resulting in a small piece of the wheel rim being dented. The material of aluminum alloy is relatively brittle, and the recessed position may be damaged. If it is forced to return to its original state, it may cause the rim to rupture. Although some wheels are dented to the point that they can be restored to their original positions and can be used normally, car owners should go to a 4s shop or repair shop to check them carefully, and do not restore them by themselves. A hole in the rim does not necessarily need to be replaced, mainly depends on the location and condition of the damaged rim. If the side of the rim is knocked into a hole, it does not need to be replaced in this case. If there is a pit where the rim meets the tire wall, and the pit is serious, it needs to be replaced. Because the tire and the sidewall will be affected by this pit, it may cause the tire pressure to decrease, which is a safety hazard.

1. For beauty: Supercars and performance cars look better than regular cars. The so-called face value is not only the body line, but also the cool big wheels. Wheels that are too small will look petty. 2. For braking performance: The brake discs and calipers of performance cars are larger than those of ordinary cars. So, even if you don't consider the small wheel rim to be unsightly, the smaller space on the inside can't hold so much stuff! The larger hollows between the rim banners are more conducive to the heat dissipation of the braking system. 3. For maneuverability: This is also the core point. Larger wheels, the starting point is to "hold up" large tires with low aspect ratios. These tires have large diameters, low heights, and wide treads. With the tires installed, the outermost rim of the rim is closer to the ground (less tire rubber is between the rim and the ground). Therefore, when accelerating, braking, and especially turning, the tire deformation is smaller, and you can feel an excellent road feel (the feeling that the wheel transmits from the road to the hand). At the same time, the large wheels of supercars and performance cars are generally lighter, which greatly reduces the unsprung weight (the total weight of a series of swing arms, tires, wheels, tie rods, etc. below the shock absorber is a performance indicator). Therefore, these points add up, and the handling of the vehicle can be better played.

Whether it is the original wheelrim or the modified wheelrim, it has quietly undergone very severe tests, mainly including three "levels" including impact test, bending fatigue test and radial fatigue test. All clearances can be put into production and sales. Therefore, the inspection of the wheel rim is a very serious and life-threatening link. So, how do you know if the wheel is qualified or not? There is a certification body! Let's take a look at the mainstream wheel certifications in the world. German TÜV: is the abbreviation of the German "Technical Supervision Association" and is also an official certification body designated by the German government. This is a certification body recognized by many major countries around the world. And because Germany has unlimited speed highways, the country has higher requirements for wheel certification. Extended information: You may see a lot of TÜV institutions, explain, they are all true. Including three different companies, TÜV Rheinland, TÜV SÜD and TÜV NORD. The certificates of the three companies are similar, and their validity is the same in the EU. In China, these three are in a competitive relationship. U.S. DOT: Abbreviation for the U.S. Department of Transportation. According to the FMVSS standard of the National Highway Safety Administration under the U.S. Department of Transportation, in order to ensure driving safety, automobile wheels sold in the U.S. market must pass DOT certification, and the corresponding certification marks must be printed on the products. The competent authority for "DOT certification" is NHTSA (National Highway Traffic Safety Administration), which is responsible for developing and enforcing relevant regulations and overseeing vehicle safety and compliance assessments. Japan VIA/JWL: Both usually appear at the same time. Note: VIA is not a certification standard, but an agency, short for Japan Vehicle Inspection Association. JWL means light alloy wheels in Japan. The Ministry of Land, Infrastructure, Transport and Tourism of the country has stipulated the quality/performance standards of light alloy wheels , and those that meet the requirements will be marked with the JWL logo. VIA/JWL are engraved on the wheel together, indicating that the brand wheel has passed the certification of the VIA agency using the JWL standard. In addition, there are SFI in the United States, EMARK in the European Union, KC in South Korea, CMVR in India, ESMA in the United Arab Emirates, INMETRO in Brazil and CHAS in Argentina, etc. It can be seen that as long as the country pays sufficient attention to traffic safety, there will be a corresponding access mechanism for auto parts.

The more beautiful the aluminum wheels are, the thinner the spokes are, and the more mysterious the technology is. In the market, high-end cars are generally equipped with novel patterns, and the spokes are simple and delicate, which is very dazzling. Is this the trend? Trend and fashion are pushing the spokes of aluminum alloy wheels to become thinner and more mysterious. What kind of technology can push forward? What kind of limit can "mysterious" reach? 1. What is the ultimate production process for aluminum alloy wheels? There are two production processes for aluminum alloy wheels, one is casting and the other is forging. Compared with the forged rim, the metallographic structure of the former is broken grain and forged structure, and the latter is dendritic grain and as-cast structure. In terms of single mechanical performance indicators, the general increase of forging is 30% - 50%, and the individual indicators are several times higher. In the international market, the price of forged wheels can be twice as high as that of cast wheels. There is no suspense about the production technology limit of aluminum alloy wheels, it can only be forged. 2. How many production processes are there for forged wheels? One is "solid forging". For truck aluminum wheels with simple structure, we can produce them by solid forging process. The second is "casting first and then forging". For more and more exquisite car and motorcycle wheels, it is difficult to produce a single solid forging. This requires the use of "casting first and then forging", first using traditional processes such as low-pressure casting, gravity casting, metal mold casting and other processes to produce basic shapes of blanks, and then changing to a forging machine for precision forging. Most of the wheels with very complex structure and beautiful appearance can be produced by this process. The third is "continuous casting and forging". The "continuous casting and forging" process can produce forged wheels with more complex structure and more exquisite patterns than "first casting and then forging". The comprehensive mechanical performance is one grade higher than that of the cast rim, and the spokes will be more concise and finer, and more beautiful like fairy bones. 3. Status of "Continuous Casting and Forging" Process and Equipment of Aluminum Alloy Wheels "Continuous Casting and Forging" process also has many manifestations. For the special production of blanks with a specific structure, a special machine can be developed. The most advanced aluminum alloy wheel "continuous casting and forging" equipment is born out of the "extrusion die-casting die forging machine", and is made into a special machine according to the characteristics of the wheel. This kind of aluminum alloy wheel "continuous casting and forging" special machine, the name can be called "opposite three forging pressure low pressure casting liquid die forging wheel rim machine". The equipment is equipped with three large-tonnage die forging cylinders. After the low-pressure filling of the wheel rim blank casting is completed, the forced die forging is directly performed, and the "rim", "spoke" and "rim" of the wheel rim are independently forged. Make the rim blank reach the grain of the forged structure. The mechanical strength is increased by more than 20%, the impact resistance is increased by 200%-500%, and the surface finish of the wheel rim can reach the highest level of 7-8, which is comparable to the mirror reflection effect produced by machining. 4. Continuous casting and continuous forging of magnesium alloy forging wheels The production equipment for magnesium alloy forging wheels is the same as the production equipment for aluminum alloy forging wheels. The only difference is that the smelting and pouring of magnesium alloy soup needs to be protected. The forging process is the same for both. To cast the aluminum ring, a sand mold is first created by casting sand. The hollow part of the mold is what we hope to look like after casting. Then heat the aluminum material to its melting point, so the aluminum becomes a liquid, and then pour the metal liquid into the sand mold and wait for it to cool down. At this time, open the mold and you can see a formed aluminum alloy rim. As for forging the aluminum ring, it is also necessary to make a mold first. The difference is that this mold must be made of sturdy steel instead of cast sand. Because during forging, the aluminum material does not reach the liquid state, but the temperature is raised until the aluminum material becomes soft. At this time, the material is put into the steel mold, and then continuously punched with great force, the aluminum material in the mold is completely It is extruded into the shape reserved by the mold, and the forged aluminum alloy rim is formed at this time. Regardless of whether it is a forged or cast product, it needs to be mechanically processed when it is taken out of the mold, such as removing burrs, trimming the appearance, baking paint, etc., to complete the finished rim. From the perspective of molds, forging molds are much more expensive than casting molds, and it is more difficult to open molds; from the perspective of construction methods, casting is easy to mass-produce, and forging is just a manufacturing process, not as simple as casting, so the price is also expensive. . During the forging process, the material undergoes continuous stamping. After forming, its structure will become very compact and solid, and can withstand high stress. That is to say, if the car runs over the road pothole, the cast aluminum ring may be deformed. However, the forged aluminum ring may be safe and sound. Secondly, because the forged aluminum ring has a compact structure and can withstand high stress, in terms of shape design, it can design a relatively lively thin spoke, and there is no need to worry about the bearing capacity is not strong enough. When the size is the same, it can also be lighter than the cast wheel frame, which can improve the "loaded mass/unloaded mass ratio" of the whole vehicle, and the handling performance of the car can be improved without other adjustments or changes. Good performance cars, without exception, all use forged aluminum rims.

We know that the characteristics of overall forging (such as BBS, Rays, TWS, OZ and other brands), that is, in the forging process, aluminum ingots do not destroy molecular bonds like casting, and molecular bonds can be preserved to the greatest extent. In the process of forging the spokes, the metal streamlines generated by these microscopic molecular bonds at the macroscopic angle are further extruded and strengthened, and the microscopic metal molecules are further pressed to be more compact, so that the forged rim has very good mechanic performance. In "custom forging", the spokes are not extruded by a forging press, but are engraved by CNC, which lacks the step of strengthening and strengthening, and then the cutting process will directly cut off the molecular bonds on the surface of the rim, which has a negative impact on the mechanical properties of the rim. Therefore, in order to achieve the performance of the overall forged rim, a custom forged rim must use more materials, resulting in weight gain; if the former pursues light weight, its performance is not as good as the overall forged rim, or even the same weight. of spin-cast rims. Although the mechanical properties of custom forging are indeed inferior to that of overall forging, the advantage of custom forging is that CNC cutting has a higher degree of freedom in the design of the rim, some very exaggerated and individual shapes, and the casting and forging processes have limitations and cannot be helped. It can be done by CNC cutting, so gorgeous and changeable shape is the first selling point of "custom forging". The second selling point is "customization". Some car owners who like to play with posture need to customize the specified ET (a parameter of the rim's outer throw range) and width, which is the advantage of customizing the rim; and some "exotic" cars, For example, the PCD of the GM series is 115, and the PCD of the Ford/Volvo series is 108. The PCD of these cars is very unpopular. There are few suitable rims in domestic stock, so it is difficult for car owners to choose their favorite rims. Custom forged rims can freely choose PCD, which is a blessing for unpopular car owners.

Casting is the literal meaning. The aluminum alloy raw material is heated and melted into a liquid, and then poured into the mold. After cooling and solidification, it becomes a wheel rim. Casting wheels are also divided into low-pressure casting and high-pressure casting. Low pressure casting has low cost and fast production pace, and the original wheelrims are generally low pressure casting. In order to pursue the lightweight effect, the modified rim will pressurize after the aluminum water mold, so that the molecules of the metal after cooling are more closely combined, so as to optimize the mechanical properties and achieve the lightweight effect. Forging a wheel rim is to directly "pinch" aluminum into a wheel rim, relying on a forging press that can generate tens of millions of tons of forging pressure. Because the forgedrim does not need to undergo the melting-solidification process, the molecular shape does not change, the molecular bond does not break, and in the process of pressure forging, the intermolecular bonding becomes tighter, so the mechanical properties are better than castrims . In theory, monolithic forging can achieve the greatest rigidity-to-weight ratio. This means that for the same weight, the rigidity of the forged rim is higher (that is, commonly known as "hard"); or at another angle, to achieve the same rigidity goal, the forgedrim can be made lighter. What are the disadvantages of forged wheels besides being expensive? Because the forged wheel rim is to "pinch" a piece of aluminum alloy into a wheelrim, and the ductility of the aluminum alloy is not very strong, so: 1. The freedom of design of the forged wheel rim is relatively limited; 2. Since it is to "pinch" , In addition to the limited freedom of modeling, excellent raw materials cannot be used, otherwise it will be difficult to form; and it is extremely difficult to "pinch" thick and dense spokes in the forging process, and the transition between the spokes and the "rim" is also difficult to make. Very thick thickness for extreme strength. For these two reasons, the challenge of extremely high hardness still relies on the casting process.