![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
The lightweighting of trucks is a systematic project that involves the entire vehicle, engine, suspension and other fields, and even includes the application of new materials and new technologies. The automobile body accounts for about 30% of the total weight of the car. Under no-load conditions, about 70% of the fuel consumption is spent on the body weight. For every 100 kilograms of vehicle weight, 0.6 liters per 100 kilometers can be saved. If the vehicle weight is reduced by 10%, the fuel efficiency can be increased by 6%-8%; if the rolling resistance is reduced by 10%, the fuel efficiency can be increased by 3%; if the transmission efficiency of the axle, transmission and other devices is increased by 10%, the fuel efficiency can be improved. Increase by 7%. Therefore, lightweight vehicles are of great benefit to the vehicle's fuel economy, vehicle control stability, and collision safety. In particular, under the toll-by-weight basis, how much net income each year users will increase can be calculated for each ton of vehicle weight reduction.
In Europe and other developed countries, reasonable freight rates and high value-added goods are lighter in order to pursue higher transportation efficiency. With the constant weight of cargo carried, the vehicle body can be reduced in weight to achieve higher vehicle speed and less fuel. The purpose of consumption and reduction of pollutant emissions. China and Europe have different freight environments and different levels of economic development. In China's freight market, the low price of freight and low value-added raw material transportation make overloaded products still the mainstream.
At present, weight-based tolls have been imposed on virtually all expressways in the country, and more stringent overload management has been stipulated, which stipulates the maximum weight of goods and vehicles that are allowed to drive on the road. How can we improve both the quantity and the cost of the current shipment? Heavy truck companies are only trying their best to reduce their weight.
In the current case where domestic heavy self-respect is 15%-20% higher than that of a foreign model, the first is to optimize the vehicle design structure, and the second is to apply new materials on the basis of optimizing product structure. In the advanced stage of the application of new materials such as aluminum alloys, magnesium alloys, rubbers, and plastics, the world’s leading heavy-duty heavy-duty giants have started from the basic design, optimized the structure, and rationally used new materials and technologies. Without reducing the carrying capacity, the overall weight reduction is achieved while China’s heavy truck companies are still busy at the initial stages of how to reduce weight and optimize the design of the vehicle body.
For example, heavy-duty trucks adopt aluminum alloy gearboxes, the small leaf spring structure of the Hongyan bearing system, and Shaanxi Automobile's lightweight frame have achieved the goal of lightweighting. Covering the entire generation with lightweight concepts is an overall upgrade without sacrificing any performance of the vehicle. The pioneering use of advanced technologies such as air suspension, aluminum alloys, vacuum tires, etc., set up the Swiss Union heavy truck but it is at the forefront of the market, which shows that the company's product R & D personnel intelligence and wisdom. Although Jirui United Heavy Trucks has not yet been listed, this advanced design concept is worth learning and admiring! Moreover, the author also participated in the preliminary product research and development and market research work, which gave birth to a few years of heavy truck products is a sentiment, and so far have been affectionate colleagues who have worked together with deep feelings!
Lightweight heavy-duty trucks, on the one hand, can save fuel and Dora runs fast, making money. When customers buy a car, especially when they buy trucks and tractors, their weight becomes a very important factor. Even if the price is slightly higher, trucks with light weight will be the first choice for customers.
In general, every 10% reduction in the weight of a car will reduce fuel consumption by about 8%. This is undoubtedly very attractive to truck users who are struggling to survive in the era of high oil prices. If the vehicle's own weight is reduced by 0.8 tons, it can be loaded with 0.8 tons of cargo. According to the annual freight of 200,000 kilometers, the average freight rate is 0.28 yuan per kilometer, a lightweight heavy truck can increase the income of 50,000-60,000 yuan a year compared to an ordinary vehicle with the same load. yuan.
The management of overloading and weight-based charging are just the main motives for promoting the development of domestic heavy-duty trucks in the direction of lighter weight, and not only promote the upgrading of products and technologies, but also reduce the weight. And in order not to repeat past homogenization competition in the high-end market, research and development of lightweight vehicles with unique adaptability have become the second motivation for the internal development of the company.
For example, the weight of 6×2 twin-axle lightweight tractors produced recently by Shaanxi Auto was 600-800 kilograms lower than the non-lightweight model on the Steyr platform, only 7.5 tons, which was lighter than that of competitors’ lightweight models. 600 kg. It is reported that in the same model with the same total weight of goods, Shaanxi Automobile heavy trucks can pull 0.4-0.6 tons more than their competitors, and the direct economic benefit is as high as 36,000 yuan a year. Another example is that a truck company will change the original 306-mm double-deck beam of a tractor to a 273-mm double-beam frame, so that the weight of one vehicle can be reduced by about 500 kg. The double front steering axle 6×2 heavy-duty tractor can reduce one driving axle when the bearing capacity is basically the same as the 6×4 model. Although there is one more steering axle than the 6×4 model, the weight of the steering axle is It is hundreds of kilograms lighter than the drive axle.
At present, the majority of lightweight heavy trucks launched by domestic heavy truck companies are viewed from the perspective of core technology content, but there is still a certain gap between them and foreign high-end heavy trucks. The practice of domestic companies adopting parallel lightweight products outside the existing mainstream products is fundamentally different from the practice of reducing the weight of the entire product line during the upgrade process.
Heavy vehicles are known for their durability and strong bearing capacity. Users who request heavy loads or work in harsh conditions. According to relevant data, due to the reduced carrying capacity, many domestic lightweight heavy trucks can no longer adapt to the traditional car environment with high-intensity overload and long-term driving under bad road conditions. They can only work within the nominal load range, and on better-conditioned roads, they are more suitable for transporting lightweight, high-value goods. For specific vehicles with a single use and limited maximum load, the same lightweight technology route can also be adopted. If the user is still overloaded, it will cause serious damage to the lightweight heavy truck.
Right now, domestically-made lightweight heavy trucks, most aluminum alloy fuel tanks, fewer leaf springs or rubber suspensions, biased tires for radial tires, twin tires, etc., mostly stay in relatively simple parts replacement and lighter. Materials used. Or change the drive axle to a steering axle and change the double-layer beam to a single-layer beam, which is also a commonly used technical measure for domestic lightweight heavy trucks. However, due to the limitation of the technical level of domestic metal materials, it is not only that the weight loss is limited, but also that the weight-bearing capacity of the vehicle is greatly reduced.
In this “lightweight†boom in recent years, China’s joint venture component manufacturers’ automatic transmissions, aluminum alloy housing transmissions, fewer leaf spring suspensions, rubber suspensions, air suspensions, composite materials, and high-strength steel sheets Frames and other technologies have developed rapidly and the market has grown bigger and bigger.
However, at the same time, on the cusp of this lightweight speculative truck, Tan Hsueh-Qing, heavy-duty truck product technologist, calmly pointed out: “I think lightweighting is a concept of hype. There is no practical significance. Can lightweight vehicles be used? If If it is bad, what is the significance of lightweighting? Lightweighting should be a reflection of the overall improvement of society and the improvement of transportation efficiency. Now it has become a concept used by companies for hype."
He said: "I'm worried that some companies' lightweight products are cutting corners and can't use them. There are still questions. Some people say that the price reduction is to reduce unnecessary consumables, but according to this statement, then our truck reverts to 30 years ago, Steyr was "lightweight" because at that time the thickness of the steel plate was thinner than it is now, and the price of lightweight vehicles using alternative materials would certainly not be cheaper, instead, ordinary steel was used instead. After the strength steel, the price should rise because high-strength steel is expensive, and if the problem of overloading cannot be solved, the impact of the policy and users’ unscrupulous use of vehicles may bring the weight reduction of heavy trucks in China into misunderstanding. In addition, the technology of some companies is still not up to the requirements, and lightening at this time is actually cutting corners. By reducing the thickness of steel plates and the number of accessories, on the surface it is lighter, but it will eventually threaten the safety of drivers. Safety is the bottom line. There is no point in skipping safety talk and reducing weight."
The author's good friend - heavy-card market analysis expert - Mr. Xia Shu also wrote in the article: "Lightweight heavy truck is a revolution or evade the policy and change the enchanting? "The current light weight boom is a show of pseudo-technical progress in the context of high oil prices caused by the financial crisis. The real technological progress is to use vehicle attendance and reliability as an indicator to ensure safety. Technological progress to achieve the lowest unit fuel consumption to enhance the efficiency of social logistics."
Mr. Xia further pointed out: “Is the lightweight boom in China's heavy-duty truck industry really a prelude to the return of value? However, the overall technological progress of the Chinese heavy-duty truck industry has not fundamentally changed the value concept of the entire industry. Lightweight heavy trucks and double-steering axles, like the 6x2 heavy-duty tractors, are all domestic heavy-duty truck companies that evade the enchantments of the country’s laws.â€
However, I believe that the “lightweight†of the truck, whether it is “enchanting†or “immortalâ€, is one of the most significant signs of the convergence of China's auto industry and the international community. It is a general trend in the general direction, but it is just the speed of technological progress. But still need the drums and calls of the people!
According to "China's No. 1 Commercial Vehicle Network," it is reported that at present, under the condition that the toll-by-weight pricing regulations are about to be fully promoted, due to the high price of domestic oil prices, the lighter weight of heavy-duty trucks will reduce users' considerable use costs. The current lightweighting trend of domestic heavy trucks is mainly reflected in the following major aspects.
1. Variable-section, small-leaf spring structure The leaf spring is a variable cross-section. The leaf spring is composed of several leaf springs with variable cross-sections in the longitudinal direction, which not only reduces the weight, but also improves the driving force by reducing the friction between the leaf springs. Comfort and long life. In addition, the use of rubber suspension or air suspension can also reduce the weight of the suspension system.
2, the use of a single frame frame beam Compared to the leaf spring, the weight of the frame is greater, effectively reduce the weight of the frame, will greatly reduce the vehicle's overall quality. With the improvement of design level, manufacturing process, and improvement of material properties, single-layer frames are fully qualified under standard load conditions.
3, the use of composite materials The cab is the most composite assembly, especially the outer cover: front panel, angled panels, fenders, bumpers, and even the top cover, have used a large number of composite materials. On the one hand, this effectively reduces the weight of the entire vehicle. On the other hand, due to the good formability of the composite material, the molding structure can be more complex, more beautiful, and more accurate in size than the metal stamping. At present, domestic heavy trucks still prefer the structure of the cab of an all-steel structure, which is mainly related to the harsh working environment of heavy trucks in China. From the perspective of new products introduced by heavy-duty truck manufacturers in recent years, the proportion of composite materials used in vehicles is gradually increasing, and the use of a large amount of composite materials is an inevitable trend.
4, the use of aluminum alloy materials Aluminum alloy is less dense than steel, so in some parts of the composite material can not be replaced, you can use aluminum alloy materials, including sheet metal parts and castings. Aluminum alloy sheet metal parts are the most representative of the fuel tank, aluminum alloy tank material, not only reduce the weight, and the oil tank is not easy to rust, eliminating the trouble of regular cleaning. The body can also use aluminum alloy instead of cold rolled steel. The rim, engine body, transmission body, etc., can also be cast aluminum alloys in a large amount, which can minimize the weight while ensuring sufficient strength and rigidity.
5, the use of high-strength steel using high-strength steel plate, can reduce the thickness of the steel plate, thereby reducing weight. In European and American heavy trucks, almost 100% of steel used in heavy trucks is high-strength steel. In the past, the proportion of high-strength steel plates used in domestic heavy trucks was relatively small, and they have been widely used in recent years. Even the cars of dump trucks have begun to use high-strength steel plates to improve the strength of the car and reduce its own weight.
6. The use of welded blanks The cab is stamped and welded with steel plates. Since the structure and force of each part are different, different sheet metal parts will also use different grades of steel plates. A heavy truck may use several cabs. Ten different steel plates with different thicknesses. However, with the development of CAE technology, through simulation experiments and analysis, it is possible to calculate the stress of different parts of the same sheet metal part. In order to reduce the unnecessary thickness of some parts, laser tailor-welding technology came into being. Laser welding technology is to combine two or more steel plates with different surface treatments, different steel types, and different thicknesses into one steel plate by laser welding.
7, the use of casting parts Traditional punched and welded structural parts, due to the limitations of materials and manufacturing processes, all parts can only be equal thickness, in order to ensure the overall strength and rigidity of the parts, punching and welding parts are often more heavy. The structural parts can be analyzed by CAE through finite element software to optimize the structure. According to the force conditions of each part, the complex variable thickness and variable cross-section structure are designed to maximize the reduction of unnecessary Local thickness, which greatly reduces the weight of parts.
8, the use of vacuum tires and ultra-wide tires The use of vacuum tires and ultra-wide tires can also reduce the weight to some extent. Compared with traditional tires, vacuum tires not only reduce the inner tube, but also reduce the structure of the rims. The entire vehicle is replaced with a vacuum tire and the running resistance is small, which can reduce the fuel consumption to some extent. The driving wheels of the heavy trucks generally use double tires. If they are changed to ultra-wide tires, they will not only reduce the number of tires, but also reduce the number of rims. In addition, the ground area of ​​an ultra-wide single tire is not smaller than that of a double tire. Besides reducing its own weight, it can also improve running stability and avoid the phenomenon of “gesture†of the dual tires.
9. Integrate the functions of parts and reduce the number of parts Integrate functions of all parts, integrate multiple parts, realize multi-functional parts, reduce the number of parts, make its structure more compact, and can also reduce the weight of the whole vehicle to some extent. Such as: the tank and the platform pedal combination, the tank and SCR urea tank combination.
Elevator Door Operator,Automatic Door Operator,Door Operator
Hitech Elevator Co., Ltd. , http://www.elevator-control-traction.com