Rivets: An Integral Fastener with Numerous Uses(casted material Winfred)

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Rivets are a ubiquitous fastening system used in a wide variety of applications from aircraft to bridges to consumer products. A rivet consists of a cylindrical shaft and head on one end. During installation, the rivet is placed in a pre-drilled hole and the tail end is upset, or deformed, to create a second head, clamping the joined materials together. Rivets offer numerous advantages that have led to their popularity and widespread use.
Structural Strength
One of the foremost reasons rivets are used extensively is their ability to provide excellent structural integrity for the assembly. The riveting process creates a tight clamping force that secures materials tightly together against vibration and shock loads. The upset deformation of the rivet shank provides a positive mechanical lock even if clamping forces relax over time. This makes rivets ideal for critical structural applications like aircraft, bridges, heavy machinery, and more.
Reliability
Properly installed rivets provide a very reliable, long-lasting fastening method. Unlike many other fasteners, rivets do not come loose over time. The upset process essentially “cold welds” the rivet shank to the materials being joined, creating a permanent solid fastening. Rivets installed decades ago in structures like the Eiffel Tower and Brooklyn Bridge continue to perform reliably today. This makes rivets a trusted fastening method for critical applications where joint integrity is paramount.
Weight Savings
Compared to other fastening methods like bolts and screws, rivets can provide significant weight savings, especially for large assemblies. Rivets require access to only one side of a joint for installation. Bolts and screws require access to both sides of the joint, often necessitating extra brackets, collars, and other hardware. The rivet shank fills the entire hole volume, maximizing fastening area for the hole size. These factors allow designers to use fewer, smaller fasteners with rivets compared to bolts or screws, an important consideration in weight-sensitive applications.
Simplified Assembly
The blind fastening nature of rivets also greatly simplifies assembly processes. Workers can rivet joints rapidly from one side without alignment challenges. Multi-layer and complex assemblies with hundreds of fasteners can be riveted efficiently in a single operation. Automated riveting systems are commonly employed for high volume production, allowing very rapid installation. This has made rivets the fastener of choice for manufactured products with sheet metal enclosures and other large-scale assembly applications.
Appearance
The smooth, unthreaded exterior of tubular rivets provides a clean appearance that is aesthetically pleasing for many products and structures. The round rivet head shape avoids sharp corners that can catch and snag materials during handling and use. Rivet heads can be customized with various shapes and even colors to achieve desired styling effects. Compared to the utilitarian look of bolts and screws, rivets often deliver a higher quality, finished appearance.
Cost Effectiveness
Rivet installation requires access to only one side of a joint and no threading or bolt alignment is necessary. This allows less skilled labor to efficiently join assemblies with rivets. The specialized machinery needed for high volume riveting is an economical capital investment compared to other fastening methods. These factors make riveting a very cost effective fastening choice for many manufacturers. The raw material cost of rivets is also very economical, especially for common aluminum and steel rivets.
Consistent Quality
Modern rivet manufacturing processes ensure consistent quality and reliability. Computer-controlled machines mass produce rivets to precise tolerances at high volumes. Statistical process controls monitor critical parameters like material chemistry, hardness, and dimensions. Rivets also receive functional testing during production for shear and tensile strength. This facilitates quality assurance and standardization across rivet suppliers to meet various industrial specs. The consistency improves process efficiency for rivet consumers.
Wide Material Selection
Rivets are produced from a vast array of materials to suit different application requirements. Most common are aluminum and steel for structural applications. Stainless steel, copper, and brass rivets offer corrosion resistance. Exotic alloys like Inconel and Monel provide high strength and temperature resistance. Plastics and polymer rivets minimize scratching and marring. This extensive material range allows engineers to select optimal rivets based on strength, weight, corrosion, electrical conductivity, cost, appearance, and other factors.
Ease of Inspection
The exposed heads of installed rivets allow quick visual inspection to check for any damaged, loose, or missing fasteners. Automated optical inspection systems can scan riveted assemblies and identify any defects. Missing or compromised rivets are easily replaced by drilling out the old rivet and installing a new one. Replacing damaged bolts or screws is much more labor intensive and may require access to both sides of the joint. The inspectability of rivets is a major asset for quality control.
Environmentally Friendly
The riveting process generates no harmful chemicals, fumes, oils, or contaminants. Rivet installation produces only metallic chips that are easily recycled. Rivets contain no volatiles to offgas or leach during service. At end of service life, riveted assemblies are readily dismantled and recycled. These attributes make rivets much more eco-friendly than many coating, adhesive, and thermosetting processes. Riveting provides manufacturers with a “green” fastening solution.
Design Flexibility
Rivets are available in a nearly limitless array of diameters, lengths, head shapes, and material combinations. This allows designers tremendous flexibility to select the optimal rivet for any joint design. Custom-designed specialty rivets can also be sourced for unique applications. The simplicity of rivetted joints also facilitates modular product architectures and simplifies re-design or retrofits. These benefits make rivets a very design-friendly fastening choice.
Rivet Types
While basic rivets are simple cylindrical shafts, many variations exist to suit different applications:
Blind Rivets – Also called pop rivets, these have a mandrel through the center of the rivet that is pulled to upset the tail. Allows riveting from one side when access to the backside is limited.
Drive Rivets – Also called screw rivets, these have a head that allows driving with a screw driver or hex key for easy installation removal. Used where occasional rivet access is needed.
Large Flush Rivets – Feature a 100 degree countersunk head that finishes flush with the material surface for a smooth appearance. Used extensively in aircraft assembly.
Split Rivets – These have a notch in the shank so the rivet can collapse radially inward during installation. Minimizes distortion of delicate materials.
Structural Rivets – Extra large rivets that require pneumatic, hydraulic, or impact tools for installation. Provide extreme shear/tensile strength for critical structural joints.
Multi-Grip Rivets – Single rivet length suits a range of material stack-ups. Reduces inventory requirements.
Solid Rivets – Made entirely from the head material rather than hollow shaft. Used for high strength connections.
Semi-Tubular Rivets – Hollow shaft but partially solid head section. Balances cost and strength.
The list above highlights just some of the more common variants that exist. Engineers select the optimal rivet type based on joint design, assembly method, cost, strength, and other factors.
Installation Methods
Hand Tools – Manual hand tools like squeezers and hammers provide portability and economy for low volume riveting.
Pneumatic Tools – Fast, reproducible results make pneumatic squeezers and hammers ideal for high production riveting.
Hydraulic Tools – Powerful hydraulic presses provide the extreme forces needed to install large structural rivets.
Automated Riveting – Programmable robots optimize throughput for very high volume production. Excellent for repeatability and quality.
Again, application demands dictate the best installation method. Portability, speed, access, and quality requirements are key considerations.
Riveting Systems
While rivets provide the actual fastening hardware, other critical system components include:
Drilling Systems – Precisely drill holes to match rivet diameter. CNC systems maintain strict process control.
Hole Preparation – Deburring, cleaning, and surface treatments optimize hole condition for riveting.
Buckers – Support the tail side of rivets during installation to control deformation. Varies by rivet type and tooling.
Automation – Robotic arms, part handling, & assembly fixtures boost throughput and consistency.
Inspection Systems – Vision systems, leak testing, and other checks verify joint integrity.
All of these factors must align to achieve robust, reliable riveted assemblies. Experienced manufacturers optimize the entire riveting system not just the fastener itself.
Industry Applications
Aerospace – Rivets are the quintessential fastener for aircraft. Used extensively in wings, fuselages, and other structures where weight savings and reliability are paramount.
Construction – Steel rivets provide high strength fastening for cranes, bridges, transmission towers, rail lines, and buildings.
Manufacturing – Rivets assemble a vast array of products including cars, trucks, buses, trains, appliances, electronics, furniture and more.
Infrastructure – Pipe hangers, tanks, ducting, machinery, and structural frames all rely on rivets for robust and rapid construction.
Marine – Ship hulls, decks, railings and off-shore platforms all employ corrosion resistant rivets to withstand harsh sea environments.
Transportation – Cars, trucks, buses, railcars, trailers incorporate millions of rivets into frames, enclosures, and components.
Clearly rivets span nearly every industry where durable, reliable mechanical fastening is needed. New applications continue to emerge as well, proving the versatility of this venerable fastening technology.
Summary
Rivets have been an integral fastening technology for over a century owing to their unique combination of strength, reliability, efficiency, and design flexibility. Installed properly, rivets outperform most other mechanical fastening methods for structural integrity and longevity. Rivets will continue playing a critical role across countless industrial and commercial applications far into the future. Engineers and manufacturers continue finding new and innovative ways to apply rivets to solve modern fastening challenges. With myriad types and installation processes available, rivets provide an optimal fastening solution for almost any application requirement. CNC Milling