What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
GB bolts are generally divided into two types: GB30 bolts and GB21 bolts. The difference is that the hexagonal head of GB30 is larger than that of GB21. The materials are all used: Q235. The grade is 4.8, the hardness is weak, and it is used for parts with low hardness requirements and infrequent activities, which are called ordinary bolts. The most typical use: machinery, construction, fixing, fastening.
5. After the closing value material and the geometric parameters of the nut are determined, the change of the closing value has an important influence on the repeated use characteristics of the lock nut. When the closing value becomes larger, the deformation of the threaded piece increases, the strain of the threaded piece increases, the strain cycle hardening phenomenon intensifies, and the pressure FN of the threaded piece increases, which has a tendency to increase the unscrewing torque; on the other hand, the width of the threaded piece decreases. , the total area of the threaded piece decreases, the friction with the bolt decreases, the strain of the threaded piece increases, the low-cycle fatigue performance decreases, and the maximum unscrewing torque tends to decrease. Under the combined action of various factors, the change of the maximum unscrewing torque with the number of repeated uses is difficult to predict, and it can only be observed through experiments.
Spring washers are often called spring washers in the screw industry. Its materials are stainless steel and carbon steel, and carbon steel is also iron. The commonly used spring washers are M3, M4, M5, M6, M8, M10, M12, M14, M16. These specifications are more commonly used. The national standard for spring washers is GB/T 94.1-87, which specifies standard spring washers with a size of 2-48mm. Reference standard GB94.4-85 Elastic Washer Technical Conditions Spring Washer
Stamping die is a special process equipment for processing materials into parts in cold stamping processing, called cold stamping die. Stamping is to use the die installed on the press to apply pressure to the material at room temperature to make it produce Separation or plastic deformation to obtain the required parts of a pressure processing method, the technology generally used is to make corresponding holes and punches on the template, this method cannot meet the requirements for small batches and short delivery time products , the relative cost is relatively high, so a rivet die structure is required to improve the above problems.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
