When working with bolts and nuts in machinery maintenance you need to be able to distinguish between different types and sizes. This article will focus on m8 bolt dimensions to help you identify the right size fastener for your job and avoid costly mistakes.
Unlike imperial or inch-based bolts, metric fasteners are specified by diameter and thread pitch. The m8 bolt dimension indicates the bolt shaft’s nominal diameter and the number of threads per millimeter on the bolt shank. Bolts are further categorized as coarse or standard, fine or extra fine depending on their thread pitch and the type of work they will be doing. The m8 bolt dimension also specifies the bolt head shape which can be hex, socket or dome.
Bolts carry a number of loads during their life which can include stress from tightening, tensile, shear and bending. Each bolt has a maximum load which it is designed to carry and this figure is known as the proof load. It is not recommended that you use a bolt above the proof load as this can lead to premature failure. Bolts can be tested to ensure they can take the rated load by applying a test helix to them and measuring the force of rotation in Newtons (kg).
When selecting the correct bolt for your job it is important that you understand what the m8 bolt dimensions mean and how this relates to the thread pitch and the type of work the bolt will be doing. The shaft diameter, or major diameter is the measurement of the bolt’s shank. This can be determined by using a digital vernier caliper or a thread gauge to measure the distance between threads which is called the thread pitch.
The m8 bolt specification is also used to determine the nut which can be used with it. This is determined by dividing the mm bolt length by the thread pitch and subtracting the nut width. A hex bolt can be used with a hex nut or a hexagonal nut.
M8 bolts are one of the most commonly used sizes on a bike and can be found in many locations including brake and shifter lever mounting, quill stem bolts, seat post bolts and more. Usually these bolts are made of steel and are Zinc plated to protect them from corrosion. Stainless Steel bolts are also available and these have better corrosion resistance but are more expensive than the standard Zinc plated versions. Chrome and nickel plating can be added to the steel to further improve its corrosion resistance. Alloy bolts are also available which have higher strength than the standard grades of steel and can withstand even more stresses and abrasions than the standard types of steel. This makes them ideal for industrial and marine applications. They can be made to a variety of standards by the steel supplier or to customer specifications. They can also be tempered, forged or heat treated to further enhance their performance. m8 bolt dimensions