carbon steel 4.8 5.8 M2 - M10 Full Thread Square Head Screw Bolt

Description

Square head bolts are divided into 4.8 class bolts, 8.8 class bolts, 10.9 class bolts and 12.9 class bolts according to the grade of high strength.It is widely used in the electrical and electronic industry, water conservancy engineering industry, electrical products, mechanical equipment, chemical equipment, ships, vehicles, steel structures and so on.

It is distinguished from other bolts by its shallow mushroom head and that the shank cross-section of the bolt is circular for most of its length, but the portion immediately beneath the head is formed into a square section.Carriage bolts are designed to sink into the wood as you tighten the nut, essentially creating their own pockets. Except you're building with very hard wood, this should work fine.Carriage bolt is designed to sink into the wood as you tighten with nut, essentially creating their own pockets. Unless you're building with very hard wood, this should work fine. You can tap the bolts inward with a hammer as you tighten the nuts to assist.Carriage bolts are designed so that on one side of an assembly that there are no protruding bits for things to catch on. The round head part will provide that as opposed to there being a hex or square head sticking out. In your case with a chair kit the general idea is that the heads of the carriage bolts should face toward the side of the chair where the user will be. As such the threaded bolt ends will want to be down underneath or toward a generally non use for surface of the chair.

Specification

Application

A carriage bolt, coach bolt or round head square neck bolt is one type of bolt used to fasten metal to wood.And used in wood connections utilizing the square neck under the round head which will sit into the hole to prevent the head from turning.

How to use

The design of carriage bolts allows you to install the fastener without a helping hand. Below the half-round head of a carriage bolt sits a squared shoulder. First you drill a hole through material sized for the bolt, the head of the bolt will keep in place while you tighten the fastener onto the material. Use a hole too large for the bolt will result in the bolt head spinning in the material. This will not allow the carriage bolt to tighten in the material.

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