Fastener class products are a class used for connection、A mechanical element that fastens or secures two or more parts。They are widely used in various mechanical equipment、In building structures and everyday objects。Specifically speaking，Fastener products include the following types of parts：

1. bolt：

• By the head and screw（A cylinder with external threads）Two-part composition，It must fit with the nut，Used to fasten two parts with through holes。

• variety，Such as hexagonal head bolts、Full thread bolt、Fine teeth bolts, etc，It has different mechanical properties and uses。

2. stud：

• Fasteners without heads，Only both ends are externally threaded。

• Connection time，Screw one end into a part with an internal threaded hole，The other end passes through a part with a through-hole，And screw on the nut，Achieve tight connection。

• It is mainly used for one of the thicker parts to be connected、Where compact structure is required or frequent disassembly is required。

3. Screws：

• It is also composed of a head and a screw，But more variety，According to the use can be divided into machine screws、Set screws and special purpose screws。

• Machine screws are mainly used to tighten connections，Setting screws are used to secure the relative positions of two parts，Special purpose screws such as ring screws are used for special occasions。

4. nut：

• Bore with internal thread，Most of the shapes are hexagonal columns，There are also flat square columns or flat cylinders。

• Mating bolt、Use studs or machine screws，Used to securely connect two parts。

• variety，Hexagon nut、Lock nut, etc，It has different mechanical properties and uses。

5. Tapping screw：

• Similar to machine screws，However, the thread on the screw is a special self-tapping screw thread。

• Used for fastening two thin metal components，Due to its high hardness，It can be screwed directly into the hole of the member，Internal threading。

6. Wood screw：

• The thread on the screw is a special thread for wood screws，Can be screwed directly into the wooden member。

• For metal（Or non-metal）The parts are securely attached to the wooden structure。

7. gasket：

• The shape is an oblate ring，Set bolt、Between the supporting surface of the screw or nut and the surface of the connecting part。

• The main function includes increasing the contact surface area of the connected part、Reduce unit area pressure、Protect the surface of the connected part from damage and prevent the nut from loosening。

8. retainer：

• Machine mounted、Shaft slot or hole slot of equipment，Used to prevent parts on shafts or holes from moving from side to side。

• Types include elastic retainers、Steel wire ring, etc。

9. pin：

• Commonly used for positioning、Connect or lock parts，It can also be used as an overload cutting element in safety devices。

• Common types are cylindrical pins、Taper pin and cotter pin, etc。

10. rivet：

• It is mainly composed of nail rod and nail head，Join two or more parts into a single unit by riveting。

• variety，Such as hot forging forming rivet、Hollow rivet，Suitable for connection needs of different materials and occasions。

11. Assemblies and connection pairs：

• Assembly refers to the combination of multiple fasteners（screwlike、nut、gasket）A combination of products supplied together。

• The connecting pair refers to a specific type of bolt、Nuts and washers etc. are combined together，Form a complete connection system，For example, the steel structure is connected with high-strength large-hexagonal head bolts。

12. Soldering nail：

• Consists of smooth rod and nail head（Or no nail head）The composition of different fasteners，It is fixed on a part or component by welding，In order to connect with other parts。

The above fastener products have their own characteristics，Widely used in various fields。At choice，According to the specific use of the occasion、Factors such as force situation and performance requirements are comprehensively considered。