Understanding the Different Types of Hex Bolts and Their Properties
Like screws, hex bolts have had a significant influence on building our modern civilization. If you take notice, you will be able to find hex bolts used on buildings, bridges, cars and even furniture. Let’s learn about the different types of hex bolts and their properties and how you can incorporate them into your projects.
What is a Hex Bolt?
They are a type of threaded bolt which can be identified by their hexagonal-shaped head. They are usually used to fasten two pieces of materials together. Most hex bolts are either full-threaded or partially-threaded, depending on their application. For example, hex bolts used for automotive applications are usually fully threaded, which allows the bolts to be used on various gaps.
Partially threaded bolts are used when a shorter engagement with the material is needed. They also allow for more precision when aligning the two pieces of materials together.
Hex bolts are used in a variety of industrial applications and are extremely versatile. They can secure wood, metal and even concrete together with significant tensile strength. They are most often used in heavy-duty applications, and these include:
- Construction projects
- Erection of steel girders and I-beams
- Heavy steel machinery
- Fastening large wood pieces together, including structural components
- In all manner of vehicle applications
How Hex Bolts Work
Hex bolts are usually employed into either pre-tapped holes or accompanied with nuts, but this depends on the application. Hex bolts can be tightened using a range of tools but are most commonly used with a hex bolt wrench paired with socket sets that include attachments for different bolt sizes. You can also use spanners and an electric driver with a socket attachment.
The key reason that makes a hex bolt suitable for heavy-duty applications is the six-sided hexagonal shape which allows six points of contact with your tool. This allows torque to be spread evenly across all six contact points, allowing an incredible amount of torque to either tighten or loosen the hex bolt with ease.
How Hex Bolts are Made
Being one of the most popular fasteners in the world, millions of hex bolts are manufactured locally all over the world every single day. Their manufacturing process parallels that of the humble screw because of their similar shape. Hex bolts are primarily manufactured using these two methods:
Reciprocating die - After the hex bolt materials are heated up to the point where they are malleable, they are passed through a die. The reciprocating die works by having one half of the die stationary while the other half moves back and forth at a rapid pace. Every time the two halves are joined together, a bolt is formed in the cavity. When the halves separate again, the fully formed bolt falls into a collection bucket at the bottom. Using this method, the machine can produce anywhere from 150 to 250 bolts per minute, depending on the material used.
Centerless cylindrical die - After the hex head is formed, the shaft is put into a cylindrical die that creates the thread. Two or three round dies rotate around the bolt shaft quickly, cutting into the bolt material and forming the threads in the process. This forging process is excellent at producing high-strength bolts due to less fatigue on the metal.
Hex Bolt Materials
Hex bolts are made in a variety of materials for different applications. They are:
Steel - The most common material used in bolts, steel offers incredible strength while keeping costs low. They are, however, susceptible to corrosion, but this is mitigated with different finishes. You can get steel bolts with either zinc or chrome plating and galvanized steel. Steel hex bolts are manufactured in different grades with a grade number ranging from Grade 2 - 8. The higher the grade number, the harder the steel. Grade 2 is the most common bolt used in most applications, while Grade 5 is used mostly for automotive applications.
Alloy Steel - Similar to steel bolts, alloy steel is further heat treated for strength but has reduced ductility, which makes it brittle. It is extremely strong but will break apart without warning when its shear strength is reached.
Stainless steel - Made from a combination of low-carbon steel and chromium, stainless steel has enhanced corrosion resistance which makes it suitable for use in moist environments. The corrosion resistance is inherent in the material, which means the bolt can be scratched without its corrosion resistance being compromised. Stainless steel is, unfortunately, weaker than steel because of its low carbon content, which prevents it from being heat treated to strengthen the metal.
Silicon Bronze - More commonly known as bronze, it is an alloy made up of copper and tin with a small amount of silicon added into the mix. These bolts are stronger than brass and are mostly used in marine applications because of their superior corrosion resistance. They are, however, extremely costly.
Brass - An alloy of copper and zinc, brass is extremely corrosion-resistant and electrically conductive. They are, however, not as popular as a fastener because of their limited strength and are mostly used for aesthetic purposes.
Nejireo.com carries a range of hex bolts made from different materials in various sizes to suit every application. We have no MOQ, which allows you to order as many as you need without waste. Contact us today for a quotation.
