What does bolt mean and what does bolt M16 30 mean?

What does a bolt mean, the information examined by Yu Wenlong, a fastener consultant, is: bolts: mechanical parts, cylindrical and threaded fasteners with nuts.

A type of fastener consisting of a head and a screw (a cylinder with an external thread) that is used in conjunction with a nut to fasten two parts with through holes. This form of connection is called bolted connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

Yu Wenlong, a fastener consultant, believes that it is best to check the relevant information by yourself, and it is always fake on the Internet.

M24x85,24 represents the nominal diameter of the thread diameter and is also the outer diameter of the thread. 85 represents the length, which is generally used in millimeters (mm).

The letter "M" in bolt M24 indicates that the thread used belongs to the metric thread, and the number 24 followed indicates the nominal diameter of the bolt, that is, the outer diameter of the bolt that can be measured.

Under normal circumstances, there is also a tolerance phenomenon in the thread. One of the most commonly used bolts has a tolerance size of 6g or 6h. If the bolt is M24-6H, the outer diameter of the bolt that can be measured is 24mm.

If the bolt is M24-6G, the outer diameter will be less than 24mm.

Attention needs to be paid when using bolts:

1. Before using the bolt, the screw needs to be thoroughly inspected. The main thing is to see whether the bolts and nuts are rusty and whether the surface is clean. And there should be no burrs or bumps, otherwise it will affect the use.

At the same time, bolts and nuts should be able to be tightened to avoid loosening.

2. When configuring the nut and the flat washer, you need to put both sides close to the connector. Generally speaking, the nut is marked with the lettered side in the positive direction, while the washer is the sleek side in the positive direction.

3. When using bolts for the connection of pipelines or valves, it is necessary to loosen them first, so that the residual oil and gas inside can be photographed out to avoid spraying or scalding.

A bolt is a mechanical part, and at the same time, the head is a cylinder, which is mainly composed of two parts, the head and the screw.

This component is used in conjunction with a nut and can be used to secure the connector.

This form of connection is called bolted connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolted connection is a detachable connection. The anchor bolt is a kind of bolt connection form, only the nut part can be removed after assembly, and the screw part and the concrete substrate are fixed together in some form and cannot be separated.

Main technical requirements:

The material of the building anchor bolt is divided into carbon steel, stainless steel or alloy steel, which should meet the relevant national standards for mold lifting. The anti-corrosion requirements of anchor bolts should be selected according to the environmental cover conditions and durability requirements according to the table requirements. The anchoring performance of the anchor bolt must be reliable, and the indicators should meet the provisions of JG160-2004 "Expansion and Reaming Building Anchor for Concrete" product standard and product technical demonstration license.

Reason for tooth slipping: From the manufacturer's point of view, it may be that the quality of the screws and wires we use is poor, or it may be that the hexagon bolt pier is punched out, and after the teeth are rubbed, they are directly plated and not hardened. From the customer's point of view, it may be that when the customer uses the hexagon bolt, the hex key uses too much force when acting on the head of the hexagon bolt.

Or there is no mismatch between the depth of the hex key and the hexagon bolt in all aspects.

There are a lot of bolt specifications and sizes, M represents the triangular thread, the number behind M represents the nominal diameter, and the number behind the number is the length of the bolt after the cap. For example: M6 30m represents the triangular thread, 6 represents the nominal diameter of the thread is 6, that is to say, it is 6 threads, and 30 represents the length of the bolt after capping.

A type of fastener consisting of two parts, the head and the screw, which needs to be matched with the nut to fasten and connect two parts with through holes. If the nut is unscrewed from the bolt, these two parts can be separated, so the snail tanling bolt connection is a detachable connection.

National standard bolts are generally divided into two types:

GB30 bolts, GB21 bolts, the difference is that the hexagonal head of GB30 is larger than that of GB21. The material is used: Q235

The grade is graded, the hardness is weak, and it is used for parts with low hardness requirements and infrequent activities, which people call ordinary bolts. The most classic use of the letter type: machinery industry, construction industry, fixing, fastening.

m=diameter of the thread l=length of the screw For example, m24 70 means that the diameter of the bolt is 24mm, and the length of the screw is 70mm (excluding hexagonal heads).