What are the Differences between Fastener Bolts and Screws?

Bolts and screws are our common connection fasteners, which mainly play the role of connection and fixing in various fields and equipment. 

Bolts and screws

The difference between fastener bolts and screws:

1. The definition of fastener bolts and screws are different:

Bolts: Bolts are cylindrical threaded fasteners that are paired with nuts during use. It is mainly used to fasten and connect two parts with through holes. This connection form is called bolt connection.  

Screws are tools that use the physics and mathematics principles of the oblique circular rotation of objects and the friction force to cyclically tighten objects and parts. The set screw is used to fix the relative position of the machine. Screw the set screw into the screw hole of the part to be tightened, and press its end against the surface of another part, that is, fix the former part on the latter part.


2. The shape and structure of fastener bolts and screws are different:

Bolt: A type of fastener consisting of a head and a screw (cylinder with external thread). The head is mostly hexagonal, which is generally larger. 

Screw: A type of fastener composed of two parts, a head, and a screw. The head is mostly flat and crosses grooves. There are also many internal and external hexagons, which are generally small.


3. Fastener bolts and screws have different applications: 

Bolts: Generally used in pairs with nuts, for through holes, easy to replace after damage.

Screw: Normally, no nut is needed, and it is directly matched with two objects (generally, the connecting piece needs to be drilled and tapped), which is mostly used for blind holes, and the connection piece is rarely removed.


4. Fastener bolts and screws use different tools:

Bolts generally use wrench-like tools.

Screws generally use screwdriver tools.


5. The fastening of fastener bolts and screws is different:

Bolts are generally used in conjunction with nuts or screwed into machined bolt holes.

In addition to the two fastening methods of bolts, there are self-tapping screws, which are directly screwed into a soft workpiece without processing bolt holes. For example, the wood screws we call are this kind of screws.


  1. The use of fastener bolts and screws are different: 

The use places of bolts and screws are different. Bolts do not require high accuracy. Unless there is a matching requirement, general bolts are easy to disassemble, have low processing accuracy, are not limited by connecting materials, and are widely used. Bolts that require matching can withstand transverse directions.

Load: The screw is compact in structure, but cannot be disassembled frequently, and cannot withstand large forces.