A Comprehensive Guide to Types Of Fasteners and Their Functions

Published by Worthy Hardware at June 16, 2023

What are Fasteners?

Fasteners are hardware devices that mechanically join or affix two or more objects together. They create non-permanent joints; that is, the joint can be removed or dismantled without damaging the joining components. In the world of manufacturing and construction, fasteners are crucial as they hold everything together.

From automobiles to furniture, electronics to buildings, fasteners are everywhere. They come in various shapes, sizes, and materials, each with its unique function and utility. They may be as small as a micro screw in a sophisticated electronic device or as large as the bolts and nuts used in skyscraper constructions.

To understand the role of fasteners, consider this analogy: if an industry is a human body, then fasteners are the ‘connective tissues’ that hold all the ‘organs’ (components) together. Without them, things fall apart. Hence, the importance of fasteners cannot be overstated. More about us and how we contribute to the fastener industry can be found here.

Fasteners range from common household items such as screws, nuts, and bolts to specialized fasteners used in specific industries like aerospace or automotive. Among these, some of the most important ones are used in CNC machining – a cornerstone of modern manufacturing techniques. We will look into these and more in the following sections.

Common Types of Fasteners

When it comes to the world of fasteners, there’s a vast array of types, each designed for specific applications and materials. Here, we will delve into the most commonly used ones.

Bolt

While there are numerous types of fasteners in the world of hardware, bolts stand out as some of the most utilized, particularly in heavy-duty applications. They are widely employed in industries such as construction, machinery, and automotive. Let’s delve into the various types of bolts used in these applications:

Hex Bolts

Hex bolts are perhaps the most common type of bolt. Named for their hexagonal head, these bolts are typically used for wood, steel, or other construction materials. They’re widely used in construction and repair work and require a wrench or a nut driver to install.

Carriage Bolts

Carriage bolts have a round head with a square neck underneath that prevents the bolt from turning as the nut is tightened. They’re commonly used in wood applications and are ideal for fastening metal to wood or wood to wood.

U-Bolts

U-bolts are shaped like the letter U and have threads on both ends. They are used to support pipework in construction due to their ability to accommodate and support pipes. Their design allows them to distribute weight evenly, providing a secure mount.

Eye Bolts

Eye bolts are bolts with a loop or ‘eye’ at one end instead of a standard head. They’re used for attaching a securing point, rope, or cable to a structure. They’re often used in applications where tension is applied, such as hanging frames, securing wires, or holding support cables.

J-Bolts

J-bolts are, as the name suggests, shaped like the letter ‘J’. They are commonly used to suspend electrical wiring and sheet metal from wooden structures.

Flange Bolts

Flange bolts have an integral flange at the base of the head that acts like a washer to distribute the load. This makes them ideal for use in high-stress applications, and they’re often found in vehicle frames and heavy machinery.

Structural Bolts

Structural bolts are a type of heavy-duty fastener used in large scale construction projects. They are designed to withstand high amounts of stress and are often used in the construction of buildings and bridges.

Stud Bolts

Stud bolts are a type of bolt with threads on both ends. These are often used in applications where a component needs to be mounted onto a threaded hole, such as in many automotive and plumbing applications.

Screws

Screws are one of the most versatile types of fasteners available. They come in a wide range of shapes and sizes, designed for different materials and applications. Here’s a rundown of some of the most commonly used screws:

Wood Screws

Wood screws, as the name suggests, are designed for use with wood. They have a sharp point and coarse threads to grip the wood securely. The head of a wood screw typically has a slotted or Phillips drive.

Sheet Metal Screws

Sheet metal screws are self-tapping screws with sharp threads that cut into metal as they are installed. They are often used in HVAC, automotive applications, and other projects involving thin metal sheets.

Machine Screws

Machine screws have a uniform shank diameter and are designed to be used with nuts or tapped holes. They are usually driven with wrenches or screwdrivers and are ideal for applications involving metals and other hard materials.

Drywall Screws

Designed for use in gypsum board or drywall applications, drywall screws have a bugle head to prevent tearing of the material’s surface and a sharp, pointed tip for easy installation.

Deck Screws

Deck screws are designed to resist corrosion, making them ideal for outdoor use. They are typically used to fasten wood or composite boards used in constructing decks and other outdoor structures.

Self-Drilling Screws

Also known as TEK screws, self-drilling screws have a drill bit-like point that eliminates the need for a pre-drilled hole. They are often used in metal applications.

Masonry Screws

Masonry screws are used for fastening items to brick, concrete, or stone. These screws are made from hardened steel and feature a notched design that allows for secure anchoring into masonry materials.

Twinfast Screws

Twinfast screws are a type of wood screw with two threads for quicker installation. They are commonly used in woodworking and cabinet making.

Security Screws

Security screws are designed to prevent unauthorized removal, making them ideal for public facilities and other areas where tampering might be a concern. They require special tools for installation and removal.

Nuts

In the world of fasteners, nuts are the indispensable partner to bolts, creating secure joints in a variety of applications. Just like bolts and screws, nuts also come in different shapes and sizes designed for various uses. Below are some of the most common types of nuts:

Hex Nuts

Hex nuts are one of the most common types you’ll encounter. They are six-sided and are used with a wrench for tightening. They are typically used with bolts to create a secure joint.

Lock Nuts

Lock nuts, also known as prevailing torque nuts, are designed to resist loosening under vibration and torque. They are often used in automotive and aerospace applications.

Wing Nuts

Featuring two ‘wings’ that allow for hand tightening and loosening, wing nuts are used in applications where frequent adjustment is necessary and the use of tools is not ideal.

Cap Nuts

Cap nuts, also known as acorn nuts due to their shape, are used to cover exposed bolt ends for safety and aesthetic purposes.

Flange Nuts

Flange nuts have a wide flange on one end that acts as a built-in washer to distribute the load. This design eliminates the need for a separate washer.

Square Nuts

Square nuts have four sides and provide a larger surface contact area which makes them better able to withstand loosening due to vibration.

T-Nuts

T-nuts, also known as tee nuts, are designed to be driven into wood to create a threaded insert. They are often used in furniture making.

Coupling Nuts

Coupling nuts are longer than standard nuts and are used to join two threaded rods or bolts together.

Slotted Nuts

Slotted nuts have notches cut into one side that allow them to be secured using a cotter pin. They are often used in mechanical and automotive applications to ensure safety.

Anchors

Anchors are specific types of fasteners used primarily for attaching objects to concrete or masonry. Here are the main types of anchors:

Wedge Anchors

Wedge anchors are heavy-duty fasteners that are inserted into pre-drilled holes in concrete. As the name suggests, they utilize a mechanical wedging effect at the end of the anchor to secure attachments.

Sleeve Anchors

Sleeve anchors have an expandable sleeve over a threaded bolt, with a nut and washer at the end. When the nut is tightened, the sleeve expands to secure the anchor inside the hole. These anchors are versatile, as they can be used in solid concrete, bricks, blocks, or even soft masonry.

Drop-in Anchors

Drop-in anchors are female type anchors designed for use in solid concrete. They’re installed in pre-drilled holes and a setting tool is used to expand the anchor. These are commonly used for overhead applications.

Concrete Screw Anchors

Also known as Tapcon screws, these anchors cut threads into concrete, brick, or block and provide strong holding power. They are easy to install and remove, making them a popular choice for many construction projects.

Plastic Wall Anchors

Plastic wall anchors are used in drywall and other hollow wall situations. A screw is driven into the anchor, causing it to expand and grip the wall.

Hollow Wall Anchors

Hollow wall anchors, or molly bolts, are used for light to heavy duty applications in hollow walls like drywall or paneling. They expand behind the wall, providing a strong hold.

Toggle Bolts

Toggle bolts, or butterfly anchors, are used for heavy loads in hollow walls. They consist of a bolt with a pair of spring-loaded wings, which open up after being inserted into the wall.

Rivets

Rivets are unique fasteners that provide permanent solutions where disassembly is not intended. They are typically used for connecting thin pieces of metal together, and are common in automotive, aircraft, and construction industries. Here are some typical types of rivets:

Solid Rivets

Solid rivets are the oldest and most simple type. They consist of a shaft and a head, and are set by striking or pressing the other end to flatten it. Solid rivets provide an extremely strong and reliable hold.

Pop or Blind Rivets

Pop or blind rivets are tubular and have a mandrel through the center. They are installed from one side and are commonly used where the rear of the item being riveted is inaccessible.

Semi-Tubular Rivets

Semi-tubular rivets are similar to solid rivets, but have a partial hole at the tip, opposite the head. This hole decreases the amount of force needed for application by rolling the edge outward.

Shoulder Rivets

Shoulder rivets have a smooth cylindrical shaft and a shoulder that acts as a stop when installed. They allow for rotation or attachment of other components.

Drive Rivets

Drive rivets have a solid body and are installed by driving the mandrel head into the body with a hammer, causing the body to expand and clamp down on the material.

Flush Rivets

Flush rivets, also known as countersunk rivets, have a head that is flush to the surface once installed. They are used in applications where smoothness is necessary such as aircraft exteriors.

Friction-Lock Rivets

Friction-lock rivets, often used in aircraft, are a type of blind rivet that can be removed if necessary.

Washers

Washers are often underestimated, yet vital types of fasteners used to distribute the load of a screw or nut and to prevent damage to surfaces, especially soft wood and plastics. Moreover, they ensure that the fastener is pressed against a smooth surface, reducing the chance of loosening over time. Here are the most common types of washers:

Flat Washers

Flat washers are the most commonly used type. They provide a smooth bearing surface and are used under the head of a bolt or a nut to distribute the forces applied when tightening.

Lock Washers

Lock washers are used to prevent fastening or loosening due to vibrations. The two common types are split (helical spring) lock washers, which exert a spring force between the fastener’s head and the substrate, and tooth lock washers that have teeth to bite into the substrate for resistance.

Shoulder Washers

Shoulder washers, also known as shoulder insulators, are designed to insulate screws, wire, or any part from the rest of an assembly. They are often used in electronic applications.

Belleville Washers

Belleville washers, also known as disc springs, are conical-shaped washers designed to be loaded in the axial direction. They provide high load capacity in a compact design and can be used to absorb vibration, maintain assembly tension, or act as a locking device.

Fender Washers

Fender washers are flat washers with a significantly larger diameter in proportion to the center hole. This design helps distribute the load when dealing with oversized or irregular shaped holes.

Finishing Washers

Finishing washers, also known as countersunk washers, are used with countersunk screws and help to give a neat, finished appearance.

Nails

Nails are among the most common types of metal fasteners used in various applications, particularly in construction and woodworking. There are several types of nails, each designed for a specific use:

Common Nails

Common nails are the most standard type of nail used for general purposes. They are characterized by their large, flat head and thick shank. These nails provide strong holding power, making them ideal for construction projects involving heavy-duty structural work, such as framing or building decks.

Finishing Nails

Finishing nails, also known as finish nails or brads, have a small, cupped head that can be easily countersunk below the surface of the wood and covered with a filler. These nails are typically used for finishing work like molding, trim, or other detailed woodwork where the nail heads need to be hidden.

Roofing Nails

Roofing nails have a large, flat head and a shorter shank. They’re designed for use in roof installation to securely attach shingles, underlayment, and flashing. Most roofing nails are galvanized to withstand the elements and prevent rust.

Masonry Nails

Masonry nails are made of hardened steel and are used for fastening objects to brick, concrete, or other masonry materials. They have a thick shank and come in several different styles, including round, square, and fluted.

Box Nails

Box nails are similar to common nails but are lighter and thinner. They are designed for use in softer woods or thin construction materials to prevent splitting.

Special Fasteners

Special fasteners are customized hardware pieces engineered to meet specific needs that can’t be met by standard fasteners. They play crucial roles in a variety of sectors including aerospace, electronics, medical, agriculture, lighting, and automation. Here are a few examples of special fasteners:

Anchor Bolts

Anchor bolts are designed to anchor structural elements to concrete. They are typically used in construction and civil engineering.

Concrete Screws

Concrete screws are made to fasten material to concrete, brick or block. They have high pull-out values and are easier to install than alternative methods.

Panel Fasteners

Panel fasteners are often used in automotive and electronics industries. They provide quick and easy access to panels for service or repair.

Tamper-Proof Screws

Tamper-proof screws are used in public areas to deter vandalism and theft. They require special tools to install or remove.

Structural Bolts

Structural bolts are used in heavy construction where high tensile strength is needed. They are often used in steel to steel structural connections.

Hanger Bolts

Hanger bolts have wood thread on one end and machine thread on the other. They are often used in furniture and hardware applications.

Captive Panel Screws

Captive panel screws are designed to stay with the panel when it’s removed, preventing loss. They are common in electronics and equipment cases.

Aerospace Fasteners

Aerospace fasteners are used in the aerospace industry and have to comply with stringent standards of durability, reliability, and precision.

Material Used For Making Metal Fasteners

When it comes to metal fasteners, choosing the right material is crucial as it can greatly influence the fastener’s performance, strength, and resistance to environmental factors. Below are some common materials used in manufacturing fasteners and what applications they are best suited for:

Steel Fasteners: Steel is a highly versatile material and is commonly used in making fasteners. Carbon steel, alloy steel, and stainless steel are some common types used. Carbon steel is robust and cost-effective, alloy steel provides added strength, and stainless steel offers corrosion resistance.

Aluminium Fasteners: Aluminium is light, resistant to corrosion, and non-magnetic. These properties make it a good choice for applications requiring lighter weight and resistance to weathering, such as in the aerospace industry.

Brass Fasteners: Brass is corrosion-resistant and has excellent thermal conductivity. It’s commonly used in electrical components, decorative pieces, and applications exposed to water.

Copper Fasteners: Copper is highly conductive, corrosion-resistant, and non-magnetic. It’s often used in electrical applications and in environments exposed to water.

Titanium Fasteners: Titanium offers an excellent strength-to-weight ratio and is resistant to corrosion. It’s often used in demanding environments like the aerospace and medical industries.

Plastic Fasteners: Though not a metal, plastic is worth mentioning as it offers unique properties such as electrical and thermal insulation, resistance to chemicals, and low weight. Different types of plastics like Nylon, ABS, and PEEK are used, each offering unique properties. Explore the different types of plastic we work with at Worthy Hardware.

How to Choose the Right Fastener for Your Applications

Choosing the correct fastener for your project can have a significant impact on the quality and efficiency of your work. Here are some factors to consider when selecting the right fastener:

1. Determine the Load: The load that the fastener will bear is a significant determinant in choosing the right type. Different types of fasteners have different load capacities. For example, bolts can handle a higher load than screws.

2. Understand the Material: The material you are fastening will also determine the type of fastener you choose. For example, if you are fastening wood, you might choose nails or wood screws. For metal, you may use bolts, machine screws, or rivets.

3. Consider the Environment: The environmental conditions will affect your choice of fastener. If the fastener will be exposed to corrosive elements like saltwater, a corrosion-resistant material like stainless steel or brass might be ideal.

4. Think about Accessibility: If the joint will need to be disassembled and reassembled frequently, a mechanical fastener like a bolt or screw would be suitable.

5. Evaluate the Size of the Components: Smaller components may require smaller, more precise fasteners like machine screws or miniature bolts.

6. Reflect on the Application: Some applications have specific requirements that will dictate the type of fastener used. For example, the aerospace industry requires lightweight, strong, and corrosion-resistant fasteners.

7. Seek Professional Advice: If you’re still unsure about the best type of fastener for your needs, don’t hesitate to reach out to Worthy Hardware. Our knowledgeable team is on standby to offer professional advice and guide you in making the right choice.

8. Consider the Cost: While it is essential to choose a fastener that best meets your application requirements, it’s also critical to consider the cost. High-quality, specialized fasteners might cost more than standard ones, so balance the cost with the needs of your project.

9. Check for Industry Standards or Regulations (cont.): Ensure you adhere to these guidelines when selecting your fasteners. For instance, the medical, aerospace, and military sectors typically have stringent rules regarding materials and manufacturing processes.

10. Factor in Aesthetic Appeal: Depending on your project, the look of the fastener might be crucial. Some fasteners are designed to be hidden, while others, like decorative bolts or nails, can add a distinct aesthetic touch to the finished product.

11. Think about Installation Time and Ease: The speed and ease of installation can be significant, especially for large projects. A fastener that is quick and easy to install can save significant time and labor costs.

12. Consider the Lifespan of the Fastener: Depending on your project, you might need a fastener that will last a certain length of time. For instance, in construction, you would need durable, long-lasting fasteners, whereas for temporary installations, a less durable fastener might suffice.

Conclusion

Understanding the different types of fasteners is crucial for anyone in industries such as aerospace, electronics, military, and medical. As we’ve learned, each fastener has its unique properties and applications.

Whether you’re looking for screws, bolts, nuts, or special fasteners, at Worthy Hardware, we have the expertise to deliver high-quality, customized fasteners to meet your needs. Contact us today to discuss your fastener requirements and how we can help.

Frequently Asked Questions (FAQs)

Q1: What is the hardest bolt you can buy?

A1: The hardest bolt that you can buy is usually made from alloy steel like Grade 8 bolts. These are hardened more than stainless steel bolts and are often used in automotive applications.

Q2: What is the strongest special fastener?

A2: Special fasteners like anchor bolts, which are embedded in concrete and used to support structural loads, can be extremely strong. Their strength depends on their design, size, and the materials used in their construction.

Q3: What are the basic construction fasteners?

A3: Basic construction fasteners include nails, screws, bolts, nuts, and washers. These come in various sizes and materials, depending on the requirements of the construction project.

Q4: What is the most used fastening?

A4: The most used fastening method is arguably the screw. Screws are incredibly versatile and used in a myriad of applications, from simple woodwork projects to complex machinery.

Q5: What are mounting fasteners?

A5: Mounting fasteners are designed to attach, or mount, objects to a surface. These can include various types of bolts, screws, and other hardware, such as brackets and clamps.