Fasteners, also known as standard parts, are widely used in industrial production. There are many kinds of special fasteners, and various materials and properties are not the same.

In order to better implement the circulation criteria of this industry, the country has formulated some general standards according to the relevant technical conditions, which makes the circulation of fasteners play a very good amplification role.

Each fastener is material, size, appearance standards, torsion and other parameters, its circulation of packaging requirements, quantity and other detailed requirements to make the specification.

We call the national standard, Germany called German standard, Europe called European standard or international standard, the United States has the American standard and so on.

There are some general categories of fasteners according to thread and appearance:

Bolts.

We often say the bolt, all refers to a product with external thread, and in most cases, the bolt refers to the outer hexagon bolt. Of course, there are square head bolts, but they are not commonly used.

The products of bolt external thread type cannot be self-locking during installation. They must be matched with an internal thread. Some of them tap an internal thread on the matrix to let the bolt screw in. Some are threaded through a hole with a nut on the other side.

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stud type.

We commonly used stud standard, most refers to a head without a external thread fastener. For example, double – headed stud, is the typical stud products.

The stud also needs to be used with the nut, the two ends of the thread are threaded, the middle part of the smooth rod can be used as a shaft, the two head with the nut tightened, can be disassembled at any time.

Screws.

In our country, many fasteners known as screws refer to some small machine screws, such as cross pan head screws, cross countersunk head screws, and tapping screws, etc.

The only product that belongs to the large screw is the inner hexagon cylindrical head screw. Hexagon socket head screw installation process also needs to be used with an internal thread.

And tapping screw without internal thread, it can directly into the basic, using its own thread characteristics of locking.

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Nut class.

All products called nuts, regardless of shape, belong to the family of internal threads.

Nuts can be square or round or thick or thin, with different standards. But no matter what the standard nut, it is to be used with the external thread, otherwise the internal thread of the nut has no meaning.

Drilling tail tapping nail.

This is the series of self-tapping screws, wood screws used in decoration also belong to the self-tapping screws, and large hexagonal wood screws used in the installation of wood packaging, also belong to the self-tapping screws.

The standard of the gasket is more, there are round and square, toothed or toothless, the standard is particularly many, but no matter what the standard, it is used with bolts and nuts, most of the gasket is just a cushion isolation role. Only spring gasket and anti – loose type gasket, but also a little additional locking effect.

gear ring pin shaft.

There are two kinds of gear ring, hole gear and shaft gear. It is stuck in a slot and plays a role of positioning or not coming out.

It is basically used with the pin shaft. That is to use, can use to the enterprise of the ring, basically will use these products pin shaft.

Rivet welding studs. Rivet fasteners are very special, and many purchasing personnel are confused about what the standard is.

There are also many kinds of rivets, headless rivets, empty rivets, blind rivets and so on. Rivets belong to sheet metal fasteners.

The production of many cabinets and cabinets requires the use of rivet products. The same is true of welding nails, it is in some sheet metal sheet can not form a female or female thread, the use of welding can solve the problem.

Combination fasteners.

The combination of fasteners is divided into two categories, one is the combination of pan head or countersunk head to screw, this kind is some small screw products, electronic equipment used more.

There is also a large steel structure with steel bolts, it is also a combination of fasteners, because the purchase of steel structure bolts is basically a set of purchases.