What are the advantages and disadvantages of riveting, bolting, and welding?

 

Riveting is a typical method of permanent mechanical connection, widely used in thin-plate and skin structures. The load is primarily transferred through shear contact between the rivet shank and the hole wall, while radial compressive stress is generated during installation, creating a compressive residual stress zone at the hole edge. This localized compressive stress effectively reduces the stress concentration factor, thereby improving the fatigue life of the structure.

 

Main Advantages:

Excellent Fatigue Resistance: The bulging of the rivet creates a pre-compression effect on the hole wall, partially offsetting the external load and improving resistance to crack initiation.

High Vibration Environment Stability: Not easily loosened due to vibration, suitable for cyclic loading and high-frequency vibration conditions.

High Quality Inspectability: Inspection can be performed visually or through routine non-destructive testing, and maintenance is controllable.

Mature Process and Good Repeatability: Simple tools, relatively low requirements for the operating environment.

Good Economic Efficiency: Low-cost fasteners, suitable for mass assembly.

 

Main Limitations:

Requires double-sided operation (except for blind riveting).

Drilling is necessary, leading to structural weakening and stress concentration.

Repeated repairs will enlarge the hole diameter, reducing structural integrity.

Unsuitable for thick plates or high-tensile-stress load-bearing structures.

In electrical contact manufacturing, riveting is also commonly used in bimetallic structural assemblies, such as mechanically combining silver contacts with a copper substrate to form structural Electrical Contact Assemblies with both conductive and support properties.

 

 

Bolted joints are a type of detachable mechanical connection capable of withstanding tensile, shear, and combined loads, playing a crucial role in high-strength load-bearing structures. Load transfer mechanisms include friction-type and bearing-type connections, depending on the preload and structural design.

Main advantages:

High detachability: Facilitates maintenance, replacement, and structural modification.

Adaptability to various structural forms: Suitable for thick plates, complex structures, and load-bearing components.

Flexible material selection: Strength grades can be precisely controlled through heat treatment and surface treatment.

 

Suitable for high-tensile-stress structures: A reliable force path is achieved through preload. Main limitations:

A gap usually exists between the hole and the bolt, leading to stress concentration.

Fatigue resistance is generally lower than riveting.

Preload needs to be checked regularly.

Relatively high weight per unit area.

 

In the electrical industry, bolted connections are commonly used in busbar systems or high-current conductor assemblies, such as with Silver Contact Brazed Assemblies or Brazing Silver Contacts to Copper Bars structures, to achieve detachable electrical connections.

 

 

Welding is a metallurgical bonding process that achieves atomic-level bonding through localized melting or plastic flow, forming a rigid, integral structure. Its characteristics include high structural continuity, no need for drilling, and the ability to achieve sealed and high-strength connections.

Based on different heat input mechanisms, welding can be divided into two main categories: fusion welding and solid-state welding. Commonly used in modern high-end manufacturing are laser welding and friction stir welding.

 

Main advantages:

Strong structural integrity
No hole weakening problem.

High weight efficiency
No additional fastener weight.

Excellent sealing performance.
Suitable for pressure vessels and sealed structures.

Automated production is possible.
High repeatability.

 

Main limitations:

The heat-affected zone (HAZ) can alter the material microstructure.

There is a risk of residual stress and weld deformation.

Cracks can propagate across interfaces, resulting in low damage tolerance.

Quality inspection is complex.

 

Welding technology is widely used in electrical contact manufacturing, for example:

Contact Welding

Resistance Projection Welding Silver Contact

Resistance Butt Welding Silver Contact

Copper Spot Welding Silver Contact

AC Resistance Welding Silver Contact

Electric Resistance Spot Welding Silver Contact

 

These resistive welding silver contact processes achieve a high-strength bond between the silver contact and the copper substrate, suitable for structures such as Silver and Copper Welding Button Contact or Welding Electrical Silver Contact Tip Assembly.

 

 

1. Fatigue Resistance

Riveting is superior to bolting; welding has high strength in the absence of cracks, but the risk of damage propagation is high.

 

2. Structural Integrity

Welding has the highest overall integrity; riveting and bolting result in hole weakening.

 

3. Maintainability

Bolting is the best, followed by riveting; welding is the worst.

 

4. Weight Efficiency

Welding is the best; mechanical connections require additional fastener weight.

 

5. Process Complexity

Riveting is relatively simple; bolting is next; welding has the highest requirements for equipment and parameter control.

 

6. Electrical Conductivity

In the field of electrical contacts, Brazed Electrical Contacts and Electrical Contact Resistance Brazing processes can maintain low contact resistance while ensuring structural strength, and are commonly used in Brazing Contacts for MCCB and high-current systems.

 

 

Besides structural welding, brazing plays an important role in the electrical industry. Silver soldering and silver soldering technologies are commonly used to connect silver contacts to copper substrates, achieving a reliable conductive path.

 

Typical processes include:

Brazed Electrical Contacts

Contact Joining Brazing

Brazed Contacts

Brazed Electric Contacts

Silver Contact Brazing on Copper Bars

 

Brazing has lower heat input than fusion welding, reducing changes in the base material structure and improving conductivity stability.

 

 

In aerospace structures, the choice of connection method depends on fatigue life, damage tolerance, and structural redundancy requirements; in the electrical industry, connection methods are more focused on conductivity, contact resistance stability, and thermal cycling reliability.

 

There is no absolute superiority or inferiority among different connection methods, only whether they match the application scenario.

 

 

We specialize in the manufacturing and integration of high-performance Electrical Contact Assemblies, covering Brazing Electrical Contacts, Silver Contact Brazed Assemblies, and various Contact Welding processes. Our products are widely used in low-voltage electrical appliances, MCCBs, relays, and new energy power systems. We support customized Silver Contact Brazing on Copper Bars and high-reliability Resistance Welding Silver Contact solutions.

 

For more technical details about Brazed Contacts or welded silver contact assemblies, please feel free to contact us.