Uses for Rivets in CNC Machining(metal springs Olga)

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Rivets are a staple fastener used across countless manufacturing industries. While other fastening methods like welding, screwing, and gluing have grown in popularity with technological advancements, the humble rivet has remained a tried and true component. This is especially true in computer numerical control (CNC) machining, where rivets continue to play an integral role.
What Are Rivets?
A rivet is an ancient fastening technology consisting of two parts - a smooth cylindrical shaft and a head. The rivet is inserted into pre-drilled holes through the materials being joined. The excess shank is then hammered, pressing the rivet head flush against the materials. This flaring process creates a second head and permanently joins the rivet components.
Modern rivets come in many materials, sizes, and drive styles suited for specialized applications. But the basic two-headed pin concept remains unchanged. Rivets form a solid mechanical bond without altering the joined materials, making them reusable and reliable for securing dissimilar metals and other materials.
Here are some of the most common uses for rivets in CNC machining and manufacturing:
Aircraft Assembly
Aerospace is one of the largest consumers of rivets today. Thousands of rivets join the aluminum skins to underlying structures in both civilian and military aircraft. CNC machining cuts these aluminum skins and panels to precise aerodynamic tolerances. Riveting offers a lightweight and solid fastening method that won't loosen over time like screws. And rivets don't require external heat like welding, avoiding metallurgical damage.
Rivets come with round, brazier, or countersunk heads to improve airflow. CNC machines pre-drill the rivet holes and specialty tools upset the rivet shank. Aircraft-grade rivets are made of corrosion resistant materials like aluminum, titanium, or monel. The CNC process ensures each rivet head profile and hole placement matches the engineering plans.
Metal Enclosures & Frames
Electronics, appliances, furniture, and industrial equipment all utilize metal enclosures and frames. These structures are commonly built from steel, aluminum, or stainless steel. CNC machining cuts, drills, and taps the various plates, brackets, and supports to specification. Rivets then permanently fasten the components together while allowing some flexibility.
Using rivets simplifies assembly versus welding. And properly driven rivets won't come loose over time like bolts and screws. They also withstand vibration better for equipment housings. For decorative enclosures, CNC machines countersink the rivet heads to hide them from view. Riveting creates durable metal products without marring the exterior finish.
Sheet Metal Joining
From HVAC ducting to corrugated panels to automobile bodies, CNC-cut sheet metal fabrications rely heavily on rivets for fast assembly. Using short semi-tubular and blind rivets avoids the need to access both sheet sides. CNC back gauging and punching ensures properly aligned holes between sheets. Pneumatic, hydraulic, or electric rivet setting tools quickly upset the rivet shank for permanent joining.
Riveting is preferable for sheets under 1/16” thick. It doesn’t deform the metal like spot welding. And it eliminates the need for finish screws that can loosen and corrode. Proper clinching even permits riveted sheet metal parts to be disassembled for service or alteration later on. CNC-programmed riveting makes light and durable sheet metal constructs simple.
Securing Plastics
While rivets commonly join metals, they also affix many plastic components. CNC routers cut and drill plastics like polycarbonate, ABS, PVC, acrylic, and fiberglass for industrial and consumer products. Riveting offers strong fastening without damaging or marring the plastic surface as screws can. And rivets don't require external adhesives.
Plastics expand and contract more than metals. Mechanical fasteners can crack plastic frames under temperature changes and stress. But rivets allow flexibility to prevent this. Plastic rivets are also available using the same insertion and upsetting methods. Overall, riveting provides durable plastic joining with minimal surface impact - ideal for CNC-machined parts.
Permanent Fastening
Rivets create solid, permanent joints unlike temporary fasteners. Threads can strip, glue can fail, and magnets lose strength over time. But once properly driven, the flared rivet shank won't budge from vibration, shock, or sustained loads. This makes rivets ideal for critical applications like medical devices, pressure vessels, and automobile assemblies.
CNC machining is vital for drilling the precise rivet hole sizes and alignments in these products. Consistent hole positions prevent shear stress and part distortion from uneven rivet tightening. CNC automation also allows large-scale riveting better than manual assembly. Permanent riveted joins enable durable, lifelong product performance.
Easy Installation
Riveting is a simple mechanical fastening method accessible to any manufacturer, large or small. It requires only basic tools - a rivet gun, bucking bar, and drill for holes. Minimal training gets new assemblers riveting quickly. And the manual process is easy to supplement with automation. This simplicity makes rivets suitable for prototyping one-off parts as well as high volume production.
CNC automation improves rivet precision and speed but isn't mandatory. The same riveting process applied in a garage works on the factory floor. Low barriers to entry combined with strong, reliable fastening explain why riveting remains popular despite advanced joining methods. It's hard to beat the simplicity and flexibility of a good old fashioned rivet.
Improved Appearance
Smooth flanged rivet heads often enhance a product's look over protruding screw heads or messy welds. The CNC drilling process permits countersinking the rivet head just below the surface. This adds minimal thickness while improving appearance and streamlining contours. Domed screw heads stand proud and can snag on materials and fingers.
Countersunk rivets also eliminate open holes that can collect debris and moisture. By flushing with the surface, rivet heads deter rust and contamination. CNC allows perfectly matched hole and rivet diameters for maximum flushness. Riveting joins materials firmly without detracting from aesthetic design. The finishing touch of durable products.
In summary, rivets remain highly useful fasteners in today's CNC manufacturing world. From aircraft assemblies to rugged enclosures to delicate medical devices, rivets offer unique benefits other joining methods can't match. Their flexibility, strength, and simplicity keep them relevant despite advanced welding and bonding technologies. Continual improvements in rivet materials and CNC precision ensure rivets have a place in manufacturing for the foreseeable future. CNC Milling