Uses for Rivets in CNC Machining(titanium vs. aluminum Robin)
- source:YESCOM CNC Machining
Joining Metal Sheets and Plates
One of the most common uses for rivets in CNC machining is for joining metal sheets and plates. Rivets create a permanent mechanical attachment between two or more layers of material. The riveting process involves drilling or punching holes through the materials to be joined, inserting the rivet, and deforming the protruding ends with a riveting hammer or other tool. This creates a solid head on the rivet that holds the materials tightly together. Rivets allow for quick and secure fastening of sheet metal components made by CNC processes like cutting, bending, and punching.
Structural Frames and Supports
Rivets are commonly used in the construction of structural frames, supports, and other load-bearing components produced by CNC machining. The strength and permanence of riveted connections make them well-suited for assembling parts that will undergo stresses and vibration in use. CNC machining can produce holes and contours in structural pieces to facilitate rivet placement and improve joint strength. Rivets are often used along with welds and other mechanical fasteners in structural fabrication.
Joining Dissimilar Metals
CNC machining frequently involves working with different metals and materials. Rivets provide a simple and effective way to join dissimilar metals that may not be easily welded together. For example, rivets can join steel and aluminum components while avoiding some of the metallurgical challenges of fusing different metals. The mechanical grip and shoulder of a riveted connection can create a durable bond between materials. CNC drilling and hole placement helps align rivet holes in different metals precisely.
Rivets allow for joining parts in locations that may not be easily accessible for welding or other permanent fastening methods. In some cases, riveting may be performed manually or with hand tools in confined spaces. CNC machining can produce components with rivet holes placed in strategic locations to facilitate assembly in hard-to-reach areas. Riveting also avoids the high heat input of welding, which can be detrimental in some situations. This makes rivets ideal for attaching brackets, plates, and other components in remote or inaccessible areas.
Quick Repairs and Maintenance
For equipment repairs and maintenance, rivets provide a quick way to replace worn or damaged components. Removing and replacing rivets for repairs is generally faster and easier than un-welding and re-welding an assembly. Machined parts intended for field repairs and maintenance are often designed with rivets in mind to speed up disassembly and re-attachment of components. Portable hand riveting tools allow for on-site repairs of CNC machined equipment and hardware without bringing assemblies back to the shop.
Temporary and Adjustable Connections
Rivets are suitable for applications where a temporary or adjustable connection is needed. For example, rivets can attach fixtures during machining, assembly jigs, or other workholding devices where subsequent disassembly is required. Adjustable positioning with slotted holes and selective riveting also allows for a certain amount of adjustability if needed. Rivets are ideal for these temporary and semi-permanent applications because they are easily removed. A CNC machined fixture held together with rivets can be quickly taken apart when no longer needed.
Decorative and Finishing Applications
In addition to mechanical fastening, rivets have decorative uses in CNC products. Some rivets feature domed, countersunk, or colored heads for aesthetics. CNC machining can produce decorative patterns of rivet holes and heads on components like doors, panels, furniture, and enclosures. Press fit rivets without shanks can also be inserted into CNC drilled holes solely for appearance rather than fastening. These decorative touches highlight riveting as a finishing technique as well as a functional process.
Improved Corrosion Resistance
The mechanical clinching of rivet joints has the advantage of minimizing gaps that can allow moisture to penetrate a joint. Properly installed and headed rivets produce a tight connection between mating surfaces. This helps prevent corrosion from developing between joined materials. Using corrosion resistant rivet materials, like aluminum and stainless steel, further improves longevity in harsh environments. CNC machining ensures rivet holes are precisely aligned to mitigate gaps.
Lower Cost Fastening Option
Compared to welding, bolting, or adhesive bonding, riveting is generally a low-cost fastening method. The rivets themselves are relatively inexpensive hardware. Installation only requires simple tools like hammers and bucking bars. And riveting is a quick process, reducing assembly labor costs. These factors make riveting popular for cost-sensitive CNC manufacturing applications. Automated riveting systems integrated with CNC machinery can further reduce costs for high volume production.
Improved Fatigue Life
Studies have shown that riveted connections can withstand fatigue stresses better than some other joining methods. The clinching action of rivet setting introduces compressive residual stresses around the hole. This has been proven to stop cracks from initiating and propagating in service. Riveting also avoids potential weld defects and stress concentrators. So properly designed and installed riveted joints exhibit good fatigue life, especially important in dynamic components. CNC machining ensures dimensional accuracy and hole alignment to maximize this benefit.
Ease of Automation
Riveting is highly compatible with automation using CNC machining centers. Computer-controlled riveting systems can drill holes, insert rivets, upset the heads, and inspect their installation. Sophisticated vision systems can even scan joints and determine optimal rivet placement. This makes riveting suitable for automated high volume production. Robotic arms can be programmed to swing into position and accurately drive rivets in complex assemblies. CNC capabilities provide precision riveting automation with minimal operator intervention.
In summary, rivets serve a diverse range of fastening, joining, and fabrication applications with the help of CNC machining. From structural assemblies to decorative accents, CNC-produced components and hardware are often assembled with rivets due to their strength, adjustability, and ease of installation. Continued advancement in riveting technology and CNC capabilities will further expand the possibilities for this versatile mechanical fastener. CNC Milling CNC Machining