What is a Hex Bolt?
- Hex bolts are a type of threaded bolt, characterised by their six-sided hexagonal-shaped head. Hex bolts can be either fully threaded or partially threaded (featuring a clear shank along part of the body) and are suitable for use in a wide range of applications, typically machinery and construction.
- They are available in a choice of types, sizes, materials and finishes, providing the freedom and flexibility to select the bolt best suited to your particular task or application. Hex bolts are sometimes also known as hex head bolts or hexagon bolts, again due to their distinctive head shape.
What are Hex Bolts Used for?
- Hex head bolts are versatile and adaptable fasteners, making them suitable for a variety of uses across a range of industries and applications. Example hex bolt uses include hex head screws for wood, metal, and many other environments and scenarios.
- They offer strong tensile properties and most standard types can be used in multiple locations (dependent upon the material and finish). As a result, hex bolts are a widely used staple fastener.
Their primary use is for heavy-duty fixing and fastening applications. This could include:
- Within construction projects
- During the erection, repair, and maintenance of buildings, bridges, and road infrastructure
- Machinery assemblies
- Woodworking tasks such as fastening frames
- Engineering applications
- Vehicle and automotive
How Do Hex Bolts Work?
- Hex bolts can be used either in pre-tapped holes or with nuts, depending on the application. They can then be tightened using a range of tools including a hex bolt wrench, socket sets, spanners, hex keys, and ratchet spanners.
- The hexagon-shaped head ensures that it is easy to grip hex bolts from multiple angles, using different types of tool. This makes their installation and removal a straightforward process, plus ensuring it is also easy to loosen or tighten hex bolts once they are in situ.
Hex Bolt Materials
- Hex bolts are typically manufactured from steel or stainless steel. While some manufacturers offer hexagonal bolts made from other materials, steel and stainless steel hex bolts are the norm.
- Additionally, different coatings and finishes are available. These provide various qualities and appearances in order to suit a wide range of applications.
Popular hex bolt finishes include:
- Bright zinc-plated
- Zinc hex bolt
- Clear passivated
- Black oxide
Hex Bolt Sizes
- Choosing the right-sized hex bolt for your task is important, and there are several factors to take into consideration when measuring hex bolt dimensions and sizes. These are as follows:
- The length of the bolt (measured from the end of the bolt up to under the head)
- Thread size (the size of the thread, typically using ISO metric or M-style measurements)
- Thread pitch (the number of threads per inch – the finer the bolt, the more threads per inch and the higher the thread pitch)
- The ISO metric thread size system is widely used around the world. It is a handy international standard for measuring thread sizes across an array of different screw and bolt types. Each size is denoted by the letter ‘M’ followed by a number. This number indicates the outer diameter of the thread, measured in millimetres. As an example, a hex bolt with a thread size of M8 would have an outer diameter of 8mm.