When it comes to the "four major workshops" in automobile manufacturing—stamping, welding, painting and final assembly—many people are familiar with the term. Among these four workshops, however, the painting workshop is undoubtedly the most mysterious and critical link. Coating is not only related to the aesthetic appeal of a vehicle's exterior, but also directly affects its rust and corrosion resistance, thereby determining the service life of the vehicle.

In recent years, though, we have seen some new brands rushing to launch new models, resulting in rushed production, accelerated processes and insufficiently verified products. Car owners may encounter frustrating problems such as paint peeling and rusting within just a few years of driving. Such issues are absolutely unacceptable in premium brands like Audi, as they fail to meet the basic factory standards. As a pioneer among domestic premium brands, Audi's painting workshop is one of the most advanced coating production lines built in accordance with Audi's highest standards. Step into Audi's painting workshop, and you will understand the magic behind this workshop that cost 2 billion yuan to build.

"360° Rotating Cathodic Electrophoresis" ensures 360° coverage with no dead angles.

In Audi's painting workshop, every process and every detail—from cleaning, priming, basecoating, clearcoating to corrosion protection—reflects Audi's unremitting pursuit of quality and meticulous craftsmanship. Take the priming process as an example. Currently, many manufacturers adopt a process where the car body passes through the primer tank horizontally. However, this operation faces an awkward problem: air bubbles are not easily discharged from narrow spaces, and the primer cannot penetrate these areas to cover the metal surface, leaving potential rust hazards. Faced with this challenge, Audi engineers refused to compromise and instead innovatively adopted the "360° rotating cathodic electrophoresis" process.

The introduction of the "360° rotating cathodic electrophoresis" process completely solves the problems of difficult bubble discharge and uneven primer coverage in traditional priming processes. With the help of the Ro-dip reverse full-rotation immersion conveyor system, the car body performs a 360° rotation in an electrophoresis tank as deep as 5–6 meters. During this process, a voltage of up to 380V is applied, with the car body acting as the cathode in the electric field to adsorb the electrophoretic paint. This ensures that the electrophoretic paint evenly adheres to every corner of the car body—even tiny components like screws are not overlooked. This extreme attention to detail is the key reason why Audi's painting workshop can produce high-quality vehicles.

In terms of painting, the automation level of the painting workshop at Audi's Qingdao plant is simply breathtaking. An automated painting system consisting of 104 highly intelligent painting robots not only achieves 100% automated painting, but also automatically detects the thickness of the paint film, ensuring that every vehicle maintains a highly consistent production quality. This relentless pursuit of production consistency not only avoids color difference issues, but also guarantees the long-lasting uniformity of the car paint gloss, while ensuring the stability and reliability of coating quality.

Cavity Wax-Filling Process: Giving the Car Body a "Corrosion-Resistant Armor".

In addition to the inherent corrosion resistance of the electrophoretic paint, Audi's cavity wax-filling process provides double protection for the vehicle's corrosion resistance. Audi's cavity wax-filling process adopts a fully automated workflow. Through a dedicated wax-filling tank, heated liquid wax is evenly injected into the inner cavities of the car body. After cooling, it forms a dense wax film with a thickness of up to 1000 μm, which can effectively isolate air from contacting the inner cavities of the car body, thus forming an invisible "corrosion-resistant armor" that effectively prevents moisture and oxygen from subtly eroding the car body.

It is worth noting that the cavity wax-filling process is not currently adopted by many brands, most of which use cavity wax-injection technology instead. Compared with wax-injection technology, the protective film formed by wax-filling is denser and thicker, though it also comes with a higher cost. The total investment in cavity wax-filling in the painting workshop alone reached 30 million yuan, with a single wax tank valued at 4 million yuan.

It is evident that both the "360° rotating cathodic electrophoresis" process and the cavity wax-filling process are invisible to consumers. In other words, these complex and advanced processes are actually a touchstone testing an automaker's attitude towards consumers. Audi's willingness to invest heavily in pursuing ultimate corrosion protection processes once again demonstrates its dedication and commitment to coating quality.