The hottest laser welded side impact beam improves

Laser welded anti side impact beam improves safety performance

the striker strikes the side of the new car at the speed of 50km/h (see Figure 1). There are sensors in the body to obtain the simulation test signal, and the detailed information of stress can be obtained in a fraction of a second. After that, the full results of the Euro NCAP crash test were soon published in a special automotive magazine

Figure 1: Euro NCAP side impact test

euro NCAP refers to the European new vehicle assessment organization. Its spectral analysis includes atomic emission spectrometry and atomic absorption spectrometry, which were jointly established by five European governments and the European Commission in 1997. Its results have received close attention and support from the general public, so that few automobile manufacturers will easily ignore its results. Safety performance has become a very important selling point. Therefore, people pay great attention to automobile body parts related to safety. At the same time, fierce competition has prompted people to continue to study new and more economical manufacturing concepts. The scheme of combining beam and laser welding plays an important role in the process of achieving this goal for this kind of body parts

the beam used to protect against side impact is galvanized steel with high tension ultra-fine grains, with a thickness of 1.5 mm and a tensile strength of 800 to 980 n/mm2. High tensile strength of materials requires high forming force, which brings higher requirements to the machine itself. At the same time, the requirements for beam error are more strict. The fillets in the concave part are not easy to be touched. Weld quality corresponds to welding factor 1. Only CO2 lasers with an output of 4kw are considered to be used in the welding process. Although the laser provides great advantages, it puts forward high accuracy requirements for the molding machine. It is necessary to accurately locate the metal strip, especially in the welding area (see Figure 2)

Figure 2: positioning of the steel strip in the welding area

similarly, great attention should be paid to the preparation of the weld. The zinc coating in the welding area must be completely removed, because zinc particles in the welding area may cause unnecessary pores and splashes during the melting process. This problem can be solved by the equipment including edge scraping and grooving functions. Similarly, organic impurities, such as lubricants, may cause welding errors. Although the forming force is great, the use of excess lubricant must be avoided. The roller supports are under greater pressure, so they use felt as a cushion. The felt is lubricated by precision electronic equipment by carefully adding the correct amount of lubricant. In this way, the beam itself will not be affected

in order to minimize the residual stress on the beam, the manufacturer chose a processing method called "decreasing" molding, that is, the shape of its surface slowly decreases when it is close to the outlet. Compared with the horizontal forming process, this method significantly reduces the stress, which makes the accuracy of the beam higher. This is very common in the automotive industry, which requires frequent processing performance testing

different openings on the beam (see Figure 3) provide a drain for paint and rainwater. In order to achieve complete drainage, the opening must be as close to the radius bend as possible. This puts forward a more difficult requirement, because the punching process is completed when the metal is flat, and then the whole forming process is carried out. In the conceptual stage, the model calculation shows that the punching deformation may occur due to the existence of forming force. Therefore, only by transferring the punching position can the punching error meet the requirements

Figure 3: side impact beam

the assembly process of four door vehicles requires four different beam schemes, each of which has different holes, groove distances and positions. In order to achieve this, a programmable roller feeding device is placed at the pre punching device at the beginning of the production line. The programmable slab cross-section range of the segment length involves more than 100 aluminum enterprises, and the machine is placed at the end of the production line. The edge of the beam shall not have any deformation

it is generally believed that the aging and wear of circular saw blades and the long sawing time are impossible to occur in the sawing process of contour plates. The required high speed can be achieved through the scheme of cutting punch. The reason why the plate section will not be deformed is due to a special process. A groove is pre carved on the flat steel strip, and its width is equal to the width of the punch blade after adding the error. 2. There are loose parts and components during the operation of the experimental machine. Therefore, the top of the cutting blade does not need to extend directly into the material. In this way, the problem of plate deformation is eliminated. The special shape of the punch blade and the appropriate coating and lubricant make the tool life more economical

the whole device is about 30 meters long and is operated by only one person. Additional personnel are required only when changing coils and moving plates. Due to high automation, coil replacement takes only three minutes. This shows that the production line has a long normal working time. In addition, there is no need to have special skills to operate the machine. After the equipment is installed, the operator can get guidance from the manufacturer, so even companies that have never had molding experience can use this extremely economical processing equipment

samples for quality testing and reliability testing must be delivered well before the planned delivery. This is only feasible when the equipment supplier has its own test equipment available. However, at the same time, important components on the production line also need to be tested. Therefore, before starting production, most of the necessary optimization work has been carried out. In this way, even if new machines are frequently put into use due to short-term plans, there will be no accidents

if the current beam is no longer popular, it is not a problem for the equipment itself. Dexterously, the rapid tool change system enables the equipment to produce many other types of beams. This brings great flexibility to the production of shape plate manufacturers. Due to these excellent characteristics, it is no wonder that more and more people in the automotive industry are considering using molding to produce other body parts. The last important point is that the security is improved by dealing with things, and the expensive labor force is saved at the same time. (end)