Rivets - An Essential Fastening Component in CNC Manufacturing(is aluminum lighter than titanium Vera)
- source:WEINBERG CNC Machining
What are Rivets?
A rivet is a mechanical fastener that consists of a cylindrical shaft with a head on one end. The shaft is inserted through aligned holes in the parts to be joined and the tail end is mechanically deformed, usually with a rivet gun. This creates a second head that holds the rivet in place. The deformation process is called riveting or setting the rivet.
Rivets come in a variety of styles, materials, head shapes and sizes to meet diverse fastening needs. Some common types include:
- Blind rivets - tubular rivets designed to be installed from one side when access to both sides is limited. The setting tool collapses the tubular end to form the second head.
- Solid rivets - must be installed by accessing both sides of the workpiece. They offer high strength and are suitable for heavy duty applications.
- Pop rivets - tubular rivets with pre-formed heads that are set using a specialized plier-like tool. Widely used for quick repairs and temporary fastening.
- Drive rivets - tubular rivets with large domed heads designed to fill the hole flush. Require only one side access for installation.
- Structural rivets - high strength rivets designed for critical structural applications. Usually require heat treatment post-installation.
Key Uses of Rivets in CNC Manufacturing
Thanks to their versatility, strength and ease of automation, rivets serve as an indispensable fastening solution in CNC machining and fabrication for applications like:
- Aerospace and Aviation: Riveting is the predominant assembly technique in aircraft construction. Aircraft-grade rivets offer extremely high strength-to-weight ratio necessary in airframe and engine components. CNC riveting technology allows for precision fastening during airframe assembly.
- Automotive: Self-piercing rivets (SPR) are commonly used in automotive sheet metal joining. The rivet pierces the top layer of material during setting and taps the lower layer. This seals the joint and provides strong mechanical locking. CNC-controlled SPR installation robots enable mass production of vehicles.
- Appliances: Riveting offers consistent fastening of appliance panels, housings, frames and other rigid components. Automated rivet fed CNC machines allow for rapid, high-volume production.
- Electronics: Miniaturized rivets precisely fasten small, delicate electronics hardware like computer casings, circuit board mounts and device frames. CNC rivet setting systems enable accurate, repeatable joining.
- Shipbuilding: Thousands of rivets are used to assemble large marine structures. CNC controlled riveting production lines allow shipyards to prefabricate optimized riveted modules for faster field assembly.
- Construction: Rivets provide reliable, vibration-resistant fastening for connecting structural steel components like I-beams, gusset plates and support trusses. CNC hole drilling and rivet installation helps scale production.
- Furniture: Rivets assemble rigid furniture frames while allowing some shock absorption and noise reduction compared to rigid welds and bolts. CNC automation allows mass customization of rivet patterns and positions.
CNC Riveting Methods
CNC technology allows several techniques for rapid, precise automated rivet installation, including:
- Pre-loaded rivet feeds: Vibratory bowls or perforated tape on reels automatically feed loose rivets into the joining head for sequential placement.
- Automated drilling + riveting: The CNC machine drills holes aligned to the joining surface contours before installing rivets in the same program sequence.
- Robotic riveting arms: Articulated robots with rivet guns provide extensive range of motion to access confined spaces and complex contours during riveting. Offline programming optimizes robot paths and orientations.
- In-die riveting: Presses with CNC indexing set and insert rivets into the component during the stamping process for single-hit joining.
- Laser-assisted alignment: Laser projection provides real-time guidance for precisely aligning rivet holes to within 0.1mm accuracy before automated installation.
- Vision-guided systems: Machine vision aligns rivet positions to holes before setting, enabling precision joining despite potential workpiece variations.
Advantages of Rivets in CNC Production
- High strength with relatively lower installed part stresses compared to screws and welds.
- Ability to join dissimilar and thin materials not amenable to welding.
- Lower heat input than welding, minimizing chance of distortion or damage.
- Allow some vibration damping and shock absorption.
- Installation process deforms the tail precisely filling the hole and locking the rivet in place.
- Flush finish possible with countersunk or large dome head rivets.
- Relatively low skill requirements compared to manual welding/bolting.
- Wide range of head styles and material options for specialized needs.
- Fully automated feeding and installation possible with CNC systems.
- Consistent quality and process control with programmed CNC riveting.
In summary, with capabilities like precision automation, large-scale production and customization, CNC-based riveting offers numerous advantages for assembling high-quality, robust products across various manufacturing industries. Continued adoption of advanced rivet installation systems will enable manufacturers to scale up productivity while maintaining quality and driving down costs. CNC Milling