Bolt Head Types and Practical Uses

Fastener options are almost limitless. The various shapes and sizes and the practical uses for each different type can be confusing. To get more specific, the differences between a screw and bolt are almost zero. Although not always true, it's generally accepted a bolt passes through a substrate and takes a nut on the other side while a screw takes no nut because it threats directly into the object.

In regards to bolts, the types range from the fairly common Hex Bolt to the more unique hanger bolt. But which is the right one for the specific job you`re currently in the process of completing? Below is a description of a few different bolt head types and how they can be applied.

Hex bolt: a bolt with a hexagonal head and machine threads for use with a nut or in a tapped hole. Also known as hex cap Screws or machine bolts.

Carriage Bolt: a bolt with a smooth, rounded head that has a small, square section underneath. This makes the bolt self-locking when placed through a square hole or a round hole in most wood. It can be installed with only a single tool (spanner or wrench) working from one side.

Lag bolt: a bolt with a wood thread and a pointed tip.

Eye bolt: a bolt with a circular ring on the head end. Used for attaching a rope or chain.

The place bolt is manufactured at RISCO FASTENER with five or six slots in the head. The six-slot is used for customers like In the automotive industry. The five-slots are for our military distributors and are sold as a grade 5 or grade 8.

The place bolt is well-suited for flywheel, transmission and drive train applications where vibration, high stress and shock cause failure of regular hex head cap screws or bolts. The slots on top with a recessed center creates elasticity so that when it is torqued, the head distorts to maintain clamp load.