Some knowledge points of precision axis, guide rod manufacturers tell you

Guide rodThe manufacturer thinksPrecision shaft is one of the typical parts often encountered in machinery. It is mainly used to support transmission parts, transmit torque and bear load. Shaft parts are rotating parts, its length is greater than the diameter, generally by the concentric shaft of the outer cylindrical surface, conical surface, hole, thread and the corresponding end face. According to the different structure shape, shaft parts can be divided into optical axis, stepped shaft, hollow shaft and crankshaft.

Guide rodThe manufacturer thinksThe precision shaft is supported by the bearing, and the shaft section matched with the bearing is called the journal. The journal is the assembly reference of the shaft, and their accuracy and surface quality are generally very high. Its technical requirements are generally formulated according to the main functions and working conditions of the shaft, usually the following items:

1. Dimensional accuracy. Guide rodThe manufacturer thinksIn order to determine the position of the shaft, the bearing journal usually requires high dimensional accuracy(IT5 ~ IT7). Generally, the dimensional accuracy of the journal of the transmission part is low (IT6 ~ IT9).

2. Geometric accuracy.Guide rodThe manufacturer thinksThe geometric accuracy of the precision hardware shaft mainly refers to the roundness and cylindricity of the journal, outer cone, Morse taper hole, etc. In general, its tolerance should be limited to the size of the tolerance range. For the inner and outer circle surfaces with high precision requirements, the allowable deviation shall be marked on the drawing.

3. Mutual position accuracy. Guide rodThe manufacturer thinksThe position accuracy of the precision hardware shaft is mainly determined by the position and function of the shaft in the machine. Usually, the coaxiality requirements of the journal on which the transmission part is assembled to the supporting journal should be ensured, otherwise, the transmission partThe transmission accuracy of (gears, etc.)) will be affected and noise will be generated.Guide rodThe manufacturer thinksGenerally, the radial runout of the supporting journal of the matching shaft section of the ordinary shaft is 0.01~0.03mm, and the radial runout of the high-precision shaft (such as the main shaft) is 0.001~0.005mm.

4. Surface roughness. Guide rodThe manufacturer thinksGenerally, the surface roughness of shaft diameter matched with transmission parts isRa2.5~0.63micron, the surface roughness of the supporting shaft diameter matched with the bearing isRa0.63~0.16micron.

Guide rodThe manufacturer thinksThe accuracy of precision shaft products requires that the outer diameter of the precision shaft should be0.5~3mm, the length should generally be less than 300mm, the tolerance of higher precision outer diameter usually requires 1micronAround, special requirements can be reached0.4Micro Meters; in Japanese enterprises. Required roundness below0.5micronSurface roughnessra=0.025micron, the radial runout is lower1micron. Precision shafts are often non-standard custom parts, customized according to customer requirements or drawings. Precision shafts are used in many fields, such as micro motor parts, precision electronic parts, auto parts, office automation parts, household appliances and power tools.

Guide rodThe manufacturer thinksThe precision shaft is slender and small, with high dimensional accuracy and high surface accuracy.Guide rodThe manufacturer thinksThe processing technology of precision shaft is characterized by many processing methods, and the process parameters are difficult to determine.

Guide rodThe manufacturer thinksThe processing methods of precision shaft products mainly include plastic processing, metal cutting, metal thermal processing, precision grinding, surface treatment and precision cleaning. There are not only traditional heat treatment and machining, but also special surface treatment. Heat treatment includes protective atmosphere quenching, tempering, cryogenic treatment and vacuum heat treatment. Grinding can be subdivided into cylindrical grinding, inner hole grinding, plane grinding, coreless grinding, end face grinding, chamfer grinding, groove grinding, thread grinding,D-cut grinding, spherical grinding and fine grinding. The main processing methods include CNC machining, ESCO machining, cam machining and special machine tool processing; surface treatment mainly includes puffing treatment; cleaning methods include ultrasonic steam cleaning, alkali cleaning, acid cleaning, pure water automatic cleaning and ultrasonic automatic cleaning.