Manufacturing processes require joining many small and large components to make an end product. Among several joining techniques, rivets are one of the best adhering solutions for technicians. These are the types of mechanical fasteners suitable for both light and heavy-duty applications.
Here, in this article, we’ll discuss the working and different types of rivets along with their applications. So, let’s start right away!
Definition of Rivets
Rivets are non-threaded permanent mechanical fasteners that comprise a cylindrical shaft with a head and metallic pin-like tail at opposite ends. These fasteners are often made of aluminum or steel, yet other materials can also be used.
When installing rivets, the method is opposite to other fasteners, such as bolts and nuts. Moreover, other fasteners offer temporary connections, whereas rivets ensure a permanent bond. This is why they are significantly applicable for joining larger structural members, including railway engines, bridges, ships, and boilers.
Working of Rivets
Typically, you can install the rivets by punching or drilling them directly into a hole. However, make sure you drill or punch a hole that measures 1.5 mm more than the diameter of the rivet to ensure tight fastening. Once the rivet is installed, its tail comes out from another end, so the next step is to deform it. Smashing the tail of the rivet gives rise to a dumbbell shape; consequently, the second head is created.
In order to differentiate the two heads of an installed rivet, the original one is called the factory head, while the deformed end is termed the shop head or buck-tail. The double head feature of this fastener enables it to support tension loads, especially shear loads.
What are the Different Types of Rivets Used in Manufacturing?
You’ll come across several types of rivets in the market for different applications. Generally, they are divided into the following categories:
1. Solid Rivets
The archeological findings proved solid rivets as the oldest and most common fasteners. They have a simple structure consisting of a solid shaft and head. Whereas the headless part is usually deformed by hammering or a rivet gun to ensure better tightening. The head of solid rivets is either round universal or 100 degrees countersunk.
Solid rivets are ideal for applications where safety and reliability are the user’s priority. For instance, building frames, bridges, cranes, and aircraft structural parts are typical applications.
2. Blind or Pop Rivets
Blind rivets, often known as hollow or pop rivets, are tubular-shaped fasteners with a mandrel in their center. Expansion of the rivet’s blind end generally detaches the mandrel. Blind rivet is named so because it can only be installed from one side, whereas blind to the other side. Comparatively, these rivets are quick and convenient to install.
Here are some standard blind rivets that you may use:
● Pull-Mandrel Rivets
In these rivets, the mandrel head doesn’t snap off. Hence, you may consider them double countersunk blind rivets that clinch on both sides of the material and increase the structural rigidity of the component.
● Threaded Rivets
Threaded rivets are usually anchored from one side of the installed component. They possess heavy-duty heads and sidewalls that make them perfect for high-performance applications.
● Drive-Pin Rivets
Drive-pin rivets feature less clamping force than all other rivets. Typically, they consist of short mandrels projecting from the rivet’s head. These mandrels become functional as soon as you insert them inside the hole.
Drive-pin rivets are mainly suitable for aesthetic and architectural applications.
3. Tubular Rivets
As the name suggests, tubular rivets are hollow from one end, while the other contains a head. Primarily, the hollow end is responsible for sticking the rivet to the material to ensure firm joining. The hollow ends of the rivets are often cold-formed to field heads. As a result, they become ductile and low-strengthened materials, perfect for commercial applications.
Below are some types of tubular rivets:
● Compression Tubular Rivets
These rivets possess two parts and need aesthetics on both sides. Compression tubular rivets are usually compatible with soft materials.
● Semi-Tubular Rivets
The rivets that feature holes in the field end are called semi-tubular rivets. The holes are almost 1.12 deeper than the shank diameter. They are almost similar to solid rivets.
● Full Tubular Rivets
Unlike semi-tubular rivets, full tubular rivets are weaker and contain deeper holes. They are best inserted in fabric and plastic materials.
4. Split Rivets
Split rivets consist of split or saw bodies with a small pair of legs on ends. Their unique design enables them to perfectly pierce through soft materials, including leather, wood, and plastics. The sharp ends of split rivets make holes on their own, thus depriving the need for drilled or punched holes. Most commonly, they are considered as home repair rivets due to their application.
5. Flush or Countersunk Rivets
If you want a good appearance of a particular material even after installing rivets on its external surface, flush rivets should be your priority. Flush rivets not only enhance the physical appearance but also reduce turbulence and drag. According to their properties, they are preferred to use on the aircraft exterior. Moreover, you may refer to these rivets as countersunk rivets as they take advantage of countersink holes.
6. Friction Lock Rivets
Friction lock rivets are pretty similar to expanding bolts due to their structure. The only difference is their shafts that may snap below the surfaces with high tension. Its application includes aircraft construction and repair.
7. Self-Piercing Rivets
Likewise, flush rivets, the self-piercing rivets, also don’t require punched or drilled holes. Instead, self-piercing rivets undergo a cold-forging process and turn into a semi-tubular shape with a partial spot opposite the end of the head. You may install the rivet into a particular material with the help of hydraulic or electric servo rivet setters. These rivets can only fully pierce the top layer of specific material, while the bottom one is partially pierced.
Self-piercing rivets are compatible with micro-alloyed, low-carbon, zinc-coated, and pre-painted steels. Aluminum and magnesium alloys can also handle these rivets.
Commonly Used Materials for Making Rivets
Rivets are mostly made of metal materials; every material offers different applications. Therefore, you are suggested to choose the materials according to your application. Here are some popular rivet materials you may consider when buying these fasteners:
● Stainless Steel
The sturdiness and hardness of stainless steel rivets make them best for aircraft, locomotive, and power-generating industries. Moreover, stainless steel rivets have the ability to withstand deterioration and corrosion.
Using steel with low carbon characteristics to form rivets enables them to fit perfectly in different applications. This is because low-carbon steel rivets are more flexible than high-carbon steel rivets that demand more material and, in return, decrease their moldability.
When it comes to choosing some lightweight metal, aluminum stands at the top of the list for its tenderness and weight. Plus, aluminum counts in malleable metals, so it can be used to produce complex part configurations. Hence, you may prefer aluminum rivets to enjoy several applications along with strong deterioration resistance.
Another common material used for the manufacturing of rivets is copper. It is well known for its excellent heat and electricity conductivity. This property of copper makes it suitable for electrical and water applications. Additionally, copper rivets are pretty flexible in their appearance.
If you want to prevent sparks in your applications, brass rivets can be a perfect choice. The reason lies in its flexibility, low friction, and tarnish-resistant properties. Thus, you can use these rivets in gas applications to avoid sparks.
Uses of Rivets
The following are some areas where you can use rivets for different situations:
- Riveting is essential in aircraft construction to ensure the robust alignment and combination of joined parts.
- Many jewelers use rivets to connect metallic pieces while designing jewelry to avoid soldering.
- Rivets are often used in fiberglass roofing and manufacturing window blinds, doors, wind guards, hanger straps, etc.
- Rivets are significantly used for construction purposes. For insurance, as a joint, they bind many wooden materials, including furniture, shelves, cabinets, lockers, and many more.
Manufacturers looking for a better alternative to bolts, nuts, and screws, must consider rivets as their best companion. Undoubtedly, rivets are way more durable and efficient than all other fasteners available. However, to choose between the types of rivets, you should first consider your application. Hopefully, this article will help you to make the best decision.