Shaft parts are one of the common typical parts. According to the different structures of the shaft parts, they can generally be divided into three categories: optical axis, stepped shaft and special-shaped shaft. Or for solid shaft, hollow shaft, etc. They are used in machines to support transmission components, such as gears and pulleys, to transmit torque or motion. The processing technology of the stepped shaft is more typical, reflectingFinishing of shaft castingsMost of the content and basic laws of technology.

In industrial products, shaft parts are suitable for maintenance operations of one or more CNC machining parts. Shaft parts are one of the typical parts often encountered in hardware accessories. They are mainly used to support transmission parts, transmit torque and bear load. According to the different structure of the shaft parts, they can usually be divided into optical axis, stepped axis and special-shaped axis. There are three types of shafts: or divided into solid shaft and hollow shaft.

The shaft is supported by the bearing, and the shaft section matching the bearing is called the journal, and the journal is the assembly reference of the shaft. Finishing of shaft castings usually requires high precision and surface quality,Finishing of shaft castingsThe technical requirements are usually formulated according to the main functions and working conditions of the shaft, and usually include the following items:

1. Surface roughness

Generally, the surface roughness of the shaft diameter matched with the transmission portion is Ra 2.5 to 0.63 μm, and the surface roughness of the support shaft diameter matched with the bearing is Ra 0.63 to 0.16 μm.

2. Mutual position accuracy

The position accuracy requirements of the shaft parts mainly depend on the position and function of the shaft in the machine,Finishing of shaft castingsIt is necessary to ensure the coaxiality requirements of the journal of the component transmission part and the supporting journal, otherwise it will affect the transmission accuracy of the transmission part (gear, etc.) and generate noise. For ordinary precision shafts, the radial runout from the matching shaft section to the supporting journal is usually 0.01~0.03mm, and high-precision shafts (such as spindles) are usually 0.001~0.005mm.

3. Geometric shape accuracy

The geometric accuracy of shaft parts mainly refers to the roundness and cylindricity of journals, outer cones, Morse taper holes, etc., and their tolerances should usually be limited within dimensional tolerances. For the inner and outer circular surfaces requiring high precision, the allowable deviation shall be marked on the drawing.

4. Dimensional accuracy

To determine the position of the axis,Finishing of shaft castingsThe bearing journal usually requires high dimensional accuracy (IT5 to IT7), and the dimensional accuracy of the journal of the assembled transmission part is usually low (IT6 to IT9).