The Different Types of Bolt Heads and Their Uses

Type Of Bolt Heads

Bolts, as well as screws, are available in a vast variety of head shapes. These heads are made in order to grip the tools that are used to tighten them.

The most common type of bolt head types includes square, hex, slotted hex washer, and socket cap.

The earliest bolt heads in use were the square heads. Square heads consist of a square indentation on the head followed by a shaft that withstands rotation when a torque is applied to it.

Square heads are still in use today but hex heads have become more common. Hexagonal heads are used with a wrench or a spanner to provide torque.

Type Of Bolt Heads

There are numerous other head shapes in use as well, namely:

  • Flat bolt head: A counter shank head with a flat top. A flat head is designed to be countersunk into the material it is being used with. Flat heads are often used when a low-profile fastener is desired, as the head sits flush with the surface of the material it is being used with.
  • Oval bolt head: A counter shank head with a rounded head top. An oval bolt head is a type of bolt head with an oval-shaped head, rather than a hexagonal, square, or round head. They may also be used in applications where a low-profile fastener is desired, as the head of the bolt sits flush with the surface of the material it is being used with.
  • Pan bolt head: A slightly rounded head with a short vertical side. A rounded head with a flat top is often used in decorative applications. Pan’s heads are similar to round heads in that they are often used for decorative purposes, but they have a flatter top and a more rounded shape.
  • Truss bolt head: An extra-wide head with a rounded top. A truss bolt is a type of bolt with a flat, triangular head that is used to join trusses in construction and engineering applications. The flat, triangular shape of the head allows for high clamping force, which is necessary for these applications to ensure the structural integrity of the truss.
  • Round bolt head: A Dome’s head. A round head is often used for decorative purposes. Round heads are not as common as some of the other types of bolt heads, but they can be used in applications where a more decorative appearance is desired.
  • Hex bolt head: A hexagonal head. A hexagonal head that can be tightened or loosened with a wrench or socket. Hex heads are very common and are often used in a wide range of applications, including construction, automotive, and machinery. They are easy to grip with a wrench or socket, and their shape allows for high torque to be applied.
  • Hex washer bolt head: A Hexagonal head with a round washer at the bottom. A hex washer bolt is a type of bolt with a hexagonal head and a built-in washer. The washer is typically located under the head of the bolt and is designed to distribute the load of the bolt more evenly across the surface of the material it is being used with.
  • Slotted hex washer bolt head: A hexagonal head with a built-in washer and slot. The slot allows the bolt to be tightened or loosened with a screwdriver, rather than a wrench or socket. The built-in washer helps to distribute the load of the bolt more evenly across the surface of the material it is being used with, and the hexagonal head allows for high torque to be applied.
  • Socket cap bolt head: A small cylindrical head using a socket driver. A cylindrical head with a hexagonal recess, designed to be tightened or loosened with a socket. Socket heads are similar to hex heads in that they can be tightened or loosened with a socket, but they have a cylindrical shape rather than a hexagonal shape. They are often used in applications where a high level of torque is required and where a low-profile fastener is desired.
  • Button bolt head: A low-profile rounded head with a socket driver. A small, flat head with a low profile, is often used in applications where a low-profile fastener is desired. Button heads are similar to flat heads, but they have a smaller head size and a lower profile.

However, there are many similarities between bolts and screws, there are some differences too.