In the field of fasteners, bolts and screws are the most commonly used, because they are composed of screws and heads, and the head type is basically similar, so they are often confused.
Here, from the definition, structure, application, assembly tools, fastening methods, the use of these six points to systematically talk about the difference between bolts and screws.
1. Definition
The bolt refers to a cylindrical threaded fastener used in the use process and the nut is paired, and its connection form is called bolt connection, mainly used to connect two parts with through holes.
Screw is often said to be the screw (screw is actually a general term for threaded fasteners, bolts are also screws) is the use of the object's bevel circular rotation and friction to cycle and gradually tighten the tool workpiece.
2. Structure
The structure of the bolt and screw is composed of the head and screw, there are many kinds of head types, but the head of the bolt is more hexagonal, the general size is relatively large, and the head of the bolt is not necessarily with a slot, the screw is strictly cylindrical, mainly to facilitate the assembly of the nut;
The head of the screw is mostly with a slot for fastening or hexagonal, internal plum, etc., the screw is not only cylindrical, but also conical, with a pointed head, and so on.
3. Application
Bolts are generally used in through holes, and are mostly paired with nuts, and are easy to replace after damage;
Screws generally do not need to be matched with nuts, you can directly connect the two objects, the connecting parts need to be drilled and tapped first, the screws are mostly used for blind holes, and the connected parts are rarely removed.
4. Assembly tools
Bolts are basically installed with tools such as wrenches; Screws are tools such as drivers and screwdrivers.
5. Fastening method
The fastening method of the bolt is to match with the nut or screw it directly into the processed bolt hole;
In addition to the screw with the nut or directly screwed into the hole, there are self-tapping screws that can be directly screwed into the soft material of the workpiece to go to the screw, without first processing the bolt hole, such as wood screws.
6. the use of occasions
Bolt connections are generally removable, and the accuracy requirements are not high, suitable for various materials of the connection, but also can withstand lateral load;
The structure of the screw is more compact than that of the bolt, but it can not be disassembled often, and the force it can withstand is limited, and it is mostly used for blind hole connection and not much disassembly.
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