Riveting in Sheet Metal Fabrication(63 surface finish Katherine)

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Rivets are a common and effective way to join together sheets of metal in manufacturing and fabrication. Though welding and bonding are other options, riveting offers some unique advantages that make it a popular choice for many sheet metal applications.
What is a Rivet?
A rivet is a mechanical fastener that consists of two main parts - a smooth cylindrical shaft and a head. The shaft is inserted through aligned holes in two (or more) pieces of sheet metal that are being joined. The head sits on one side, while the protruding end is upset, peened, pressed, or bucked so that it flattens out. This creates a second head and clamps the sheets together between the two heads.
The rivet holds together while the upset end is Hammered, pressed or bucked around the center shaft, forming the second head. This process is called riveting.
Advantages of Rivets:
- Rivets create a highly reliable, permanent joint. The process work-hardens and expands the rivet, creating a tight fit that won't come loose over time.
- Installation is quick and requires no special skills or equipment beyond a hammer, bucking bar or rivet gun. Hand riveting is easy to perform in tight spaces.
- The joints have some flexibility and shock absorption capacity, allowing for movement and vibration.
- Riveted construction is simpler and cheaper compared to welding or bonding. Minimal surface preparation is required.
- It's easy to combine riveted joints with other techniques like welding and bonding within the same assembly.
- Inspection and maintenance is straightforward, as each rivet can be visually checked.
- Rivets are lightweight and inexpensive. A wide range of materials and sizes are available.
- Joints can be disassembled if needed by drilling out the rivets.
Types of Rivets:
There are various types of rivets used in sheet metal fabrication:
- Solid/Round Head Rivets: These are the most common type, with a rounded head on both ends. They are inexpensive and suitable for most applications.
- Countersunk Head Rivets: These have a flat, countersunk head on one end to provide a flush surface. The underside is rounded.
- Pan Head Rivets: These have a shallow rounded head with a small vertical side wall to provide a smooth finished surface.
- flush Rivets: These have heads that are flush with the surface of the sheet metal on both sides of the joint.
- Blind Rivets: These are tubular and can be inserted from only one side when access to the back is limited. The mandrel stem is pulled to expand the rivet.
- Self-piercing Rivets: As the name implies, these pierce and go through the metal sheets without needing a pre-drilled hole. Often used for brittle or hard to drill materials.
- Drive Rivets: These have large domed heads and are driven in using a riveting hammer rather than bucked from the backside. Often used for attaching items together.
- Structural Rivets: These are heavy duty rivets that can carry larger loads, used in bridges, towers, cranes, and other structural applications.
The most common materials for rivets include:
- Aluminum - Lightweight, corrosion resistant, and strong. Used for aircraft and other applications.
- Steel - Strong, durable, and inexpensive. Carbon steel, stainless steel, and alloy steel rivets are common.
- Copper - Malleable, corrosion resistant, and attractive finish. Used for boilers, plumbing, shipbuilding.
- Monel - Corrosion resistant nickel-copper alloy. Used in marine and chemical environments.
- Titanium - Very strong but lightweight. Used in aircraft, medical devices, and racing components.
Rivet Strength:
The strength of a riveted joint depends on the:
- Tensile strength of the rivet material
- Size of the rivet shank and head
- Sheet thickness - more sheets will require longer rivets
- Hole size - clearance between rivet and hole affects strength
- Spacing between rivets - more rivets spaced closely reduces load per rivet
- Quality of fabrication - alignment, hole prep, riveting technique
Usage in Sheet Metal Fabrication:
Riveting finds extensive usage in sheet metal products across industries including:
- Aircraft and aerospace - fuselage skins, wings, empennage, structures
- Heavy machinery - cranes, bulldozers, harvesters, dump trucks
- Trucks, trailers, and automobiles - panels, compartments, linings
- Railroad cars and shipping containers
- Building facades, roofs, decking, and architectural metalwork
- Electronics enclosures, shields, chassis
- Appliances such as washers, dryers, and refrigerators
- Furniture frames and office furniture like filing cabinets
- Drainage products like ducts, culverts, and eaves troughs
Rivets offer reliable and versatile sheet metal joints for both light and heavy duty fabrication and assembly work. Correct selection of rivet type and using proper installation procedures will result in durable, long lasting riveted connections. With advantages like ease of use, low cost, and flexibility, riveting will continue to be integral to sheet metal manufacturing. CNC Milling CNC Machining