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Bolts and washers appear to be relatively lightweight accessories, but do you know what they do and how to use them? This article tells you the answer.

What Are Washers and Bolts?

A washer is a ring-shaped fastener used for the supporting surfaces of bolts, screws or nuts and connecting parts. It reduces the contact surface area of the connected parts, reduces the unit area pressure and protects the surface of the connected parts from damage. Function: The spring washer can also prevent the nut from loosening.

Bolts are threaded fasteners. It is a type of fastener consisting of a head and a screw. It needs to cooperate with a nut to fasten two parts with through holes. This type of connection is called a bolted connection. Bolted connections are detachable connections.

The role of washer and bolts
Washer refers to a material made of paper, rubber sheet or copper sheet, which is placed between two planes to strengthen the seal, and a fitting provided between the static sealing surfaces to prevent fluid leakage. Generally, a screw with a nut is fixed in a through hole. The diameter of the through hole is generally slightly larger than the screw. Therefore, a washer is required to increase the contact area to protect the part. It also reduces pressure and protects parts and screws. A washer is a mechanical seal between two objects, usually used to prevent pressure, corrosion, and natural thermal expansion, contraction, and leakage of the pipeline between the two objects. Since the machined surface cannot be perfect, irregularities can be filled with shims.

The head of the bolt is generally hexagonal, and the rod has external threads. Bolts are widely used in detachable connections in mechanical manufacturing, and are generally used in conjunction with nuts (usually plus a washer or two washers).

Basic requirements for bolted connections
When ordinary bolts are used as permanent connection bolts, they shall meet the following requirements:
1. For ordinary bolted connections, flat washers should be placed under the bolt heads and nuts to increase the pressure bearing area.
2. Flat washers should be placed on the bolt head and nut side. Generally, no more than two flat washers should be placed on the bolt head side, and no more than one flat washer should be placed on the nut side.
3. For the bolts and anchor bolts with anti-loosing design, nuts or spring washers of anti-loosening devices shall be used. The spring washers must be arranged on the side of the nut.
4. For the bolt connection under dynamic load or important parts, the spring washer should be placed according to the design requirements. The spring washer must be set on the nut side.

Screws, nuts, studs, bolts, washers, rivets are all part of the fasteners. We specialize in providing various cable accessories, hardware accessories, electrical fittings, switch equipment, etc., look forward to your inquiry.