How to choose the right fastener?

Almost everyone who held a screwdriver in his handor a hammer, knows what a fastener is. This definition is suitable for any metal object, which allows you to connect two parts together. In this rather large list there are screws, screws, bolts, anchors, nuts, washers and many more various hardware. All of them are widely used in industry.

Any fastener is one or the othergroup: construction, furniture, railway, automotive or general use group. Each variant has its own additional divisions. The most diverse construction fasteners. This includes bolts, screws, washers ... in general, everything we use when we collect our own bookshelf or table with our own hands.

All hardware must meet certainrequirements. There are a large number of different standards, where the characteristics of fastening products are indicated. GOST 27017-86 describes the types and names of all types of hardware. And then each product has its own standard, which indicates all the requirements.

Any fastener related to hardware,is made of metal. It can be brass, carbon or stainless steel. If necessary, an additional coating is applied to protect the metal from corrosion. But metalware can be used without a protective layer. Often you can see screws or screws of black color - it is applied phosphated or oxidized coating. More attractive is the fastener, which has undergone additional processing by galvanizing.

All construction hardware can be divided into several groups. Consider each separately.

Metric fasteners

This group includes all types of screws, bolts,pins, nuts and washers. They serve directly for the detachable connection of parts. The manufacture of fasteners provides for the correspondence of the external thread on the screw or bolt to the internal cutting of the nut. Therefore, for each size there is a mate. The washer helps to fix the screed additionally.

Anchor fasteners

This includes hardware used forhigh loads. This fastener is used when it is necessary to fix the construction structure rigidly, for example a window or a flight of stairs. The anchor consists of two elements. The most important part is the spacer. It is she, changing from the loads, allows you to hold the entire structure. A separate position is the chemical anchor. This fastener is often used for the installation of stairs. It is based on filling the voids with a hardening component.

Dowel fasteners

It is used for walls, when necessaryhang a heavy object. In the prepared hole, first insert the dowel, and then screw the screw. It turns out a fairly rigid mount. Today dowels are made (most often) from plastic or other similar material.

Self-tapping screws

This fastener differs from the screws andbolt thread, which allows you to cut the internal thread in the details. Widely used in construction. Available for different types of materials. Screws for wood or gypsum should not be used when working with plastic or metal.

Screws

They have the same principle of action as self-tapping screws, but they are used for softer materials. The rod is half threaded, made of less hard metal.

Rivets

They are used for permanent joining of parts. Used in different areas, in the manufacture of furniture and even in the railway industry.

All fasteners have their own strength class.It can be used to judge where the product is best used. In appearance, the screws, bolts, screws and screws are very similar. They have a head of different shapes and a rod on which the thread is completely or partially carved. The screw and the self-tapping end with a pointed end, by means of which the mentioned articles are screwed into the material. The shape of the head can be semicircular, flat, square, hexagonal, hidden or semi-secret. For the convenience of screwing on the head, special splines are cut in the form of a cross or strip. Sometimes, in order to provide additional protection, non-standard slots are made that require the use of a special tool.