What Is The Principle Of Riveting?

The principle of riveting is through the plastic deformation of the rivets to form a strong mechanical connection between the connected parts. Below is a detailed description of the specific principles:
1.Core principle: plastic deformation and mechanical interlocking
Plastic deformation of rivets
During riveting, the riveting rod is plastic deformed under pressure or impact, and the premade holes of the connecting parts are filled to form the riveting head. The process is similar to the structure of a "mushroom head," flattening a metal rod so that the rivets stick to the joint.
Formation of mechanical interlocking;
Friction and mechanical bite force are generated between the deformation rivet and the hole wall of the connecting part to form a reliable mechanical interlock. This interlocking action can resist tension, shearing force and peeling force to ensure the stability of the connection.
2.Mechanical mechanism of riveting process
Pressure or impact
Cold riveting: Static pressure is applied with a rivet gun or press to gradually deform the rivet rod.
Heat riveting: Heat rivets to a plastic state after riveting to reduce the force required for deformation, suitable for riveting of large diameter or hardness.
Logistics and bottling
Under pressure, the rivet material flows to the wall and end of the hole, filling the pore and forming the rivet head. The process is similar to "squeezing toothpaste" to ensure there is no gap between the rivets and the connecting parts.
3.Mechanical properties of riveted connections
Tensile strength
The strength of the friction and mechanical bite force between the rivet head and the joint resists the pull, depending on the rivet diameter, material properties and riveting quality.
Shear strength
The shear stress between the rivet rod and the hole wall is evenly distributed and can withstand large lateral loads.
Fatigue resistance;
Riveted joints with low stress concentration factor and better fatigue life than welding are suitable for alternating loads.
4. Comparison of Riveting with Other Connections
Advantages and disadvantages of connecting method principle
Riveting Rivets are formed by plastic deformation to form mechanical interlockings. They require reliable connections, fatigue resistance and removable Prefabricated holes and do not look good
Welding Metals is melted and solidified to form metallurgical bonds with high bonding strength and good sealing
friction force transfer load of bolted threaded pair Removable, requiring high connection strength, high pretension and light weight
V. Application scenarios of rivet;
Aerospace
The connection between the hull and skeleton of the aircraft is riveted due to its excellent fatigue resistance and ability to withstand alternating loads during flight.
Bridges and buildings
Riveting is usually used for joint connection in steel structure bridges to ensure reliability and durability.
Shipbuilding
Rivets can be used to connect hull structures due to their good sealing and corrosion resistance to seawater.
6. Rivet Quality control
Rivet diameter matches aperture
rivet diameter should be slightly larger than the aperture (usually 0.1 -0.3mm larger than the aperture) to ensure that the rivet is able to fill the pores adequately.
Riveting pressure and time
Too little pressure will lead to insufficient deformation, too much pressure will lead to rivet or connection parts damage. Riveting time needs to be adjusted according to the material and diameter of the rivets.
Rivet head molding quality;
The rivet head shall be flat, crack free, and close to the surface of the connecting part with no gap.
VII. Rivet Failure mode
Loose rivets
The friction between the rivet and the connecting member is reduced by vibration or fatigue load.
Rivet breakage
rivet material is not strong enough or bears too much load, which leads to fracture.
Connection tear;
The material strength of the connector is insufficient or the stress concentration at the edge of the hole results in tearing.
Abstracts
Through plastic deformation and mechanical interlocking of rivets, the rivets can be reliably connected. It has the advantages of fatigue resistance, detachable and so on, and is widely used in aerospace, bridge and ship fields. The core is to ensure a tight mechanical connection between the rivets and the connecting parts through reasonable pressure and deformation control.