company news about Why do planes use millions of rivets instead of choosing welding?

The main reasons why aircraft use a large number of rivets are as follows.

From a structural perspective, the fuselage and other components of an aircraft are made of materials such as aluminum alloy (skin), which are difficult to weld. The high temperature generated during the welding process can cause local properties of metal materials to change, leading to deformation, residual stress and other situations. However, rivet connections can avoid these problems and better maintain the original performance of the aircraft structure.

From a maintenance perspective, rivet connections facilitate disassembly and component replacement. If a certain part of the aircraft is damaged, using rivets can make it relatively convenient to disassemble the corresponding part for repair or replacement. However, once problems occur with welded structures, they are more complicated to repair.

In terms of safety features, riveted structures are widely used in aviation and other fields with high reliability requirements. One important reason for this is their unique safety characteristics. Unlike welding, the components connected by riveting are combined through physical fixation rather than atomic fusion. This means that if cracks appear in the material, their propagation will be restricted by rivets and it is not easy for them to spread throughout the entire structure. This is because each piece of material is relatively independent. When cracks encounter the "obstacle" of rivets, their propagation paths will be changed or terminated, thereby enhancing the fault tolerance and safety of the structure. Although welding provides a tighter and more direct connection in many aspects and can reduce weight and cost, the stress concentration at the joint and welding defects may cause cracks to propagate more easily. This ability to prevent crack propagation is crucial for ensuring flight safety when subjected to extreme conditions, such as high-speed airflow pressure and vibration that aircraft encounter during flight. In addition, riveted structures are more flexible during maintenance, allowing for the partial replacement of damaged parts without the need for the entire structure to be replaced or rewelded as in welding.

In terms of practicality, the riveting process is not only simple and reliable, but also features a wide variety of rivets that can meet different structural requirements. For instance, the exterior of an aircraft needs to be kept smooth to reduce air resistance, so "countersunk rivets" are used. After assembly, these rivets are flush with the aircraft surface and almost imperceptible. It is more convenient to use "convex head rivets" inside the aircraft. In addition, in response to the complex environment inside the fuel tank, closed "blind rivets" have also emerged. Each type of rivet has its specific application scenarios, ensuring the overall performance of the aircraft structure.

To sum up, whether considering material properties, safety, or maintenance convenience, riveting is the most suitable choice.