Pins are generally used to connect, lock parts or for assembly positioning, and can also be used as parts of safety devices.The cylindrical pin is fixed in the hole by interference, and is used to fix the part, transfer power, or as a positioning part.
Generic typeCylinder Zhao, internal thread cylinder Zhao, etc
definition
Cylindrical pins are dowel pins that are used to hold relative positions between parts. It is an important auxiliary part when combined processing and assembly.
type
There are several kinds of cylindrical pins, such as ordinary cylindrical pins, internal thread cylindrical pins, threaded cylindrical pins, perforated pins, elastic cylindrical pins, etc.
Materials
Cylindrical pins are made of high-quality carbon structural steel as raw materials.Under normal circumstances, the material is mostly C35, C45, but it must be heat treated. Bearing steel is selected under high strength requirements.The elastic cylindrical pin uses 65Mn.
Standard
GB/T 119.1-2000 cylindrical pin unhardened steel and austenitic stainless steel and GBT 119.2-2000 cylindrical pin hardened steel and martensitic stainless steel
Strength calculation
Locating pins are usually subjected to little or no load, and their size is often determined by experience.The connecting pin is often squeezed and cut, but the size of the pin can be determined according to the characteristics of the connecting structure and experience, and then the corresponding strength is checked according to the force situation.The diameter of the safety pin should be determined by the strength condition of being cut when overloaded.
Interference fit properties
Interference joint fit can be divided into direct interference and interference with auxiliary parts. The former is realized by the interference fit of the two parts, and the load is transferred by the friction force. The interference fit of cylindrical pin belongs to direct interference fit.
Nature and application
Simple structure, good neutral, high bearing capacity, good variable load and impact performance, but it requires high precision machining of the mating surface.The disassembly force is large, it will scratch the mating surface, and it is a non-detachable connection. When the interference is not large or hydraulic assembly and disassembly is used, the connection is also removable.Widely used.