Uses for Rivets in CNC Machining(lazer etching Channing)
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Aircraft Assembly
The aircraft industry relies heavily on rivets for structural assembly. CNC machines are programmed to precisely drill rivet holes and dimple the sheets being joined. This process creates the countersunk rivet seats. The rivet holes must line up perfectly between multiple sheet layers to ensure proper hole alignment.
Rivet driving machines then insert the rivets into the holes and form the shop head on the other side. Aircraft grade rivets require a very tight interference fit for maximum strength. CNC allows the rivet holes and driving process to be automated for high volume production. Aircraft assemblies can contain thousands of rivets.
Metal Fabrication
CNC riveting is commonly used in fabrication of metal frames, enclosures, storage containers and machinery parts. Rivets provide a quick way to fasten sheet metal while allowing some flexibility in the joint. This is beneficial when assembling parts subject to vibration, shock loads or thermal expansion.
The CNC machine drills precision rows of rivet holes along the joining flanges. Operators then use manual or pneumatic rivet guns to install the rivets in the field. Good rivet spacing and edge distance is critical for a sound assembly. CNC programming maximizes rivet placement while avoiding internal component interference.
Rivet Nut Installation
Rivet nuts provide sturdy threaded inserts in sheet materials too thin to properly tap. CNC machining centers can be programmed to automatically insert rivet nuts into panels for use as fastener points. This eliminates the manual process of cutting threads in weak material that would quickly strip out.
The CNC uses special tooling to drill a hole, push in the rivet nut, and swage the tubular body. This creates solid machine threads in the panel. Installing rivet nuts with CNC is faster and more consistent than manual methods. It also accommodates custom thread sizes and positions.
Composite Bonding
CNC riveting provides an alternative to traditional fasteners when joining composite materials such as carbon fiber or fiberglass. Drilling holes in composites risks cracking or delamination damage. Rivets distribute load over a larger bonded area rather than concentrating stress at a single point.
CNC machines can be programmed to apply adhesive in precise metered amounts to the joint area. The rivets are then driven in to squeeze out excess adhesive. This ensures adequate bonding strength while preventing voids from overfilling. Rivet heads may also be sealed with adhesive for a smooth aerodynamic surface.
Sheet Metal Joining
Production shops use CNC riveting to join outer panels of appliances, electronics enclosures, vehicle bodies and trailers. Minimum flange space is needed since rivets do not require weld access. Portable CNC riveting systems can perform automated fastening of large assemblies directly on the production floor.
CNC programming positions the rivets in parallel rows or other patterns along the joint. This provides uniform fastening strength. Spacing and edge distance is optimized based on sheet thickness. Precision CNC hole alignment also improves the fit and appearance of adjoining surfaces.
Rapid Patterning
CNC machines excel at rapidly drilling consistent hole patterns for rivet joining. This allows efficient mass production of riveted assemblies. Hole diameter, spacing, depth and pattern can be quickly adjusted in the CNC program for each production run.
Riveting patterns may need to wrap around complex contours. CNC interpolation facilitates this by smoothly transitioning the hole positions along curving three-dimensional joint paths. Any rivet layout that can be digitally mapped is possible with CNC.
Custom Bracketry
CNC riveting shines for fabricating one-off brackets, backplanes and support structures. The hole patterns and rivet sizes can be completely customized to suit each particular application. CNC allows these complex designs to be produced rapidly without hard tooling. Changes can also be made digitally on the fly.
Low volume or prototype runs with numerous riveted joints are well suited for CNC production. No jigs or fixtures need to be constructed. Riveted web frames, equipment mounts and structural reinforcements can all be efficiently CNC machined and riveted.
Repair Work
CNC riveting has advantages for repairing or modifying existing hardware. The original rivet spacing and hole sizes can be digitally duplicated on the repaired area. This maintains rivet pattern consistency and factory spec hole alignment. Rivet driven repairs can also be completed on-site rather than disassembling large assemblies.
Blind rivets are often used for repair work since access is only needed from one side. CNC machines excel at precision placement of rivets in tight spaces with minimal clearance. Programming can avoid potential interference issues during blind rivet installation.
Improved Quality
CNC achieves more uniform rivet compression and head formation compared to manual installation. Pneumatic rivet squeezers reduce operator influence on rivet quality. This results in consistent clamp loads and improved fatigue life. Hole misalignment is also minimized for a cleaner finish.
Automated CNC production reduces potential defects and rework from human factors. Rivet spacing, edge distance, hole size and rivet insertion depth conform precisely to specifications across the entire production run.
In summary, CNC riveting is advantageous for repetitive rivet pattern fabrication, custom bracketry, critical aircraft structures, composite bonding and other applications requiring precision placement. CNC automation improves quality while saving time and costs compared to manual riveting methods. As rivets continue playing a key part in industrial manufacturing, CNC provides an efficient solution for installating them. CNC Milling CNC Machining