Rivets: An Overview of Their Uses and Manufacturing Processes(important information about cantilever snap joints Mabel)

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Rivets are one of the oldest and most widely used types of mechanical fasteners, dating back over 4,000 years. A rivet is essentially a cylindrical shaft with a head on one end. The shaft is inserted into pre-drilled holes in the materials being joined, and the head is mechanically deformed, or "bucked", causing the material to flare out and grip the sides of the hole. This creates a solid, permanent joint.
Rivets have numerous advantages that have ensured their continued use despite the development of more modern fastening methods. They are inexpensive to manufacture, easy to install, and create strong, reliable connections between materials. Rivets distribute stress evenly over a joint and can accommodate some movement due to vibration or minor flexing without coming loose. They are suitable for joining dissimilar materials and do not require overlapping pieces or precise alignment. Riveted structures can be disassembled and reassembled multiple times if necessary.
Some common applications and uses for rivets include:
Aircraft and Aerospace Applications
Rivets are extensively used in the assembly of aircraft fuselages and wings, as well as missile bodies, space vehicles, and satellites. Thousands of rivets may be used to join aluminum body panels and structural components on an airplane. Rivets are preferred for aircraft construction because of their vibration resistance, strength-to-weight ratio, and ability to be installed quickly in large quantities. Aircraft rivets are made from lightweight aluminum, titanium, or specialty alloys.
Metal Fabrication and Construction
Rivets are ubiquitous in steel bridge construction. Sections of structural steel are joined end-to-end or lap-jointed using high strength steel rivets. Riveting produces connections that can withstand the tension, compression, and torsional loads exerted on bridges. Rivets are also used to assemble steel beams, bracing, columns, and gusset plates in highrise buildings and industrial facilities.
Historically, ships were held together entirely with iron and steel rivets. Modern ship construction has transitioned to welding, but rivets are still used to some degree. The hull, decks, bulkheads, and other metal components of ships and boats are riveted for strength and watertightness. Large ship rivets may be over an inch in diameter.
Appliances and Consumer Products
Rivets securely fasten sheet metal casings on appliances, electronics, furniture, and other products. They are installed quickly and cheaply by automated riveting machines. Pop rivets are commonly used to fasten metal facades onto cabinets, charcoal grills, gutters, trailers, and assorted hardware.
Small jewelry rivets made of steel, aluminum, or precious metals like gold are used by artisans to join pendants, charms, and other components to necklaces and bracelets. Jewelry rivets allow flexible assembly and disassembly for replacing or rearranging pieces.
Off-Road Vehicles
Rivets are the preferred fastener for assembling the sheet metal frames of ATVs, snowmobiles, tractors, and other rugged off-road vehicles. Their vibration resistance prevents joints from loosening over time. Rivets also withstand trail impacts better than welds.
While auto manufacturing has transitioned primarily to welding, rivets are still commonly used to attach auto body panels, fenders, hoods, roofs, trunk lids, and trim pieces to the frame. They allow some flexing between pieces of sheet metal. Rivets are also used on interiors and under-hood components.
Manufacturing Processes
There are several methods of industrial rivet manufacturing:
- Cold Forging - Rivet blanks are forced between a die and mandrel to form the head and shaft. High production speeds possible.
- Hot Forging - Heated rivet blanks are stamped into shape. Produces strongest rivets but slower than cold forging.
- Extrusion - Riets are extruded through an orifice, like squeezing toothpaste. Smooth, uniform rivets result.
- Machining - Rivet shafts are machined to precise diameters from bar stock on lathes or CNC machines. Allows any custom shaft length.
- Casting - Molten metal is poured into molds to form rivet heads and shanks. Lower strength than forged rivets.
- Stamping - Sheet metal is punched or pressed into simple flathead rivets. Very high production rates.
After forming and trimming to length, rivet shanks may be surface treated by processes like galvanization to prevent corrosion. The head and shank are often manufactured separately and mechanically joined later during assembly.
Setting processes include:
- Pneumatic Hammers - Compressed air hammer bucks rivet. Highest energy but noisy.
- Hydraulic Presses - Use fluid pressure to upset rivet head. Consistent force application.
- Hand-held Squeezers - Versatile portable tool for field work. Requires some operator skill.
- Automatic Riveting Machines - For mass production. Multiple rivet guns. Requires precise part fixturing.
In summary, rivets have proven themselves as a simple, economical, and dependable fastening method after centuries of use across countless demanding applications. Improved manufacturing techniques and advanced rivet materials continue ensuring they remain indispensable for aircraft, construction, vehicles, machinery, and electronics. Their popularity stems from ease of installation combined with excellent mechanical properties - virtues which virtually guarantee rivets have a secure future. CNC Milling CNC Machining