Hardcore Metaverse Lecture Hall | Lesson 2: Body Connection Technology
Hello everyone, welcome to the Hardcore Metaverse Lecture Hall~ In the last class, we explored the mystery of the source of A7L's sense of security from body materials, and left a question in the article: Which technology connects the two different characteristics of aluminum and steel together? The answer is - riveting. A total of 48 Hui friends answered correctly. Are you one of them? In the previous lecture, we talked about the lightweight of body materials. Research shows that for every 1% reduction in weight of a single body, the fuel consumption can be reduced by 0.6% to 1.0%, and the exhaust gas release is reduced by 0.55%. The economic and environmental benefits of lightweight are obvious. Driven by the trend of lightweighting, more alloy materials such as steel, aluminum, and titanium will be used on the white body. Therefore, more diversified body connection processes are needed to improve the static and dynamic strength of the body structure, thereby ensuring the safety of drivers and passengers.
Our hardcore meta-universe lecture hall will use two periods to talk about the body connection technology that puts these metal parts of different materials and huge numbers together.
As we all know, the AFS body of the A7L is composed of various materials such as steel and aluminum. Different materials cannot be assembled through welding processes, so the cold connection process can be seen everywhere on the A7L white body.
"riveting" is a representative of cold connection. There is a FDS (hot melting self-tapping technology). The principle is to use the heat generated by the high-speed rotation of screws to melt the base material, increase the pressure and make threads on the base material, so that the two layers or multi-layer board materials are fixed together. The process mainly includes: material heating, hot melt penetration, conical hole forming, thread forming, screw insertion and screw tightening.
FDS The biggest advantage is that it realizes unilateral connection, which can realize the cavity connection between sheet metal and extruded profiles, which is stronger and more firmer than spot welding connection. This connection technology is particularly suitable for connections of equal tubular closed structures, such as front longitudinal beams and shock absorber brackets. It is mainly used for steel and aluminum connection on the A7L, and is used on shock absorber support and body connection.
(as shown in the picture below).
It is worth mentioning that the rivets used on the FDS on the A7L are fully imported, and the price of a single rivet is dozens of times that of the connectors used in the general welding process. Therefore, this process is usually only used in the high-end models of Audi , such as AudiTTh and the new generation AudiA8.
Another connection technology widely used in A7L white car body is SPR (lock and riveting connection). Under the downward pressure of the push rod in the rivet nose, the rivet pierces the upper layer or the two upper layer plates. Then, under the action of the rivet die, the hollow part of the rivet is opened in the bottom layer plate, forming a self-locking structure with the bottom layer plate. The entire process will not punch the lower plate, and a mechanical interlocking structure will be formed between the rivets and the upper and lower plates.
SPR is the most commonly used cold connection process for aluminum alloy body, and is very common in mid-to-high-end models. For example, it is used on AudiA8 (D3) and AudiTT, and the SPR process used in the connection of A7L has also reached 344 points.
(the above picture is the SPR riveting process)
SPR can realize the connection of different metal sheets, such as steel-aluminum connection. Under the vibration conditions of the vehicle driving, the dynamic strength of SPR is about twice that of spot welding, and the energy absorption effect is also very excellent. The A7L vehicle front cover is used, which greatly improves the safety of dynamic connections of the vehicle.
In addition, A7L also uses cold connection technologies such as clinchen and T-bolzen. During the production process, cold connections can achieve zero pollution, and do not produce harmful substances such as welding slag, smoke and dust, and are more low-carbon and environmentally friendly.
After introducing some "cold" cold connections, the "sparks" hot connection will be launched soon. What "flowers" will SAIC Audi play in traditional thermal connection technology? We will continue to introduce them to you in the next issue.
SPR can realize the connection of different metal sheets, such as steel-aluminum connection. Under the vibration conditions of the vehicle driving, the dynamic strength of SPR is about twice that of spot welding, and the energy absorption effect is also very excellent. The A7L vehicle front cover is used, which greatly improves the safety of dynamic connections of the vehicle.
In addition, the A7L also uses cold connection technologies such as clinchen and T-bolzen. During the production process, cold connections can achieve zero pollution, and do not produce harmful substances such as welding slag, smoke and dust, and are more low-carbon and environmentally friendly.
After introducing some "cold" cold connections, the "sparks" hot connection will be launched soon. What "flowers" will SAIC Audi play in traditional thermal connection technology? We will continue to introduce them to you in the next issue.
