What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Hot rolled wire rod before plating process - (cold drawing) - spheroidizing (softening) annealing - mechanical dephosphorization - pickling - cold drawing - cold forging - threading - heat treatment - inspection
With the mass production of large-scale equipment, standardization, and the concept of lean production, it has become more and more important to improve the efficiency of the assembly stage. Nowadays, when assembling small equipment, power tools and automatic bolt supply devices are basically popular, but only for M3 and smaller However, large equipment is often fastened with M8 or larger diameter bolts, and it is still in the process of combining manual and air tools. Among them, the pre-installation of the flat and spring washers on the bolts is completely manual operation. When the bolts need to be tightened in large quantities, the shortcomings of low efficiency are particularly obvious, and the flat and spring washers are easy to be scattered when manually assembled, and there are mixed installations of different specifications. Problems such as less installation and missing installation will affect the processing quality.
The flat key is simple in manufacture, reliable in operation, convenient in assembly and disassembly, and widely used. The flat key transmits torque by contacting the two sides of the keyway with the two sides, that is, the side is the working surface, so the main technical requirements for assembly are: to ensure the matching requirements between the flat key and the keyway of the parts on the shaft, and to transmit the movement smoothly and torque. The matching nature of the key and the keyway generally depends on the working requirements of the mechanism. The key can be fixed on the shaft or the hub, and can slide relative to another matching part (guide flat key); it can also be fixed on the shaft and the hub at the same time (ordinary flat key), and based on the size of the key, by changing the shaft The size of keyway and hub keyway can meet different matching requirements.
In actual use, the rivet rod body 3-2 is passed through the riveting plate 6 and the riveting plate 7, and the rivet dome head 3-1 is placed in the mold cavity 1-1, and the cover mold 2 is driven by the riveting machine to impact the rivet rod body 3-2. Because the center of the cover mold 2 is provided with a cavity 2-1 that matches the shape of the rivet dome 3-3, the end of the rivet rod 3-2 will form the rivet dome 3-3. However, due to the rivet When the riveting machine is impacted and vibrated, a large amount of oxide slag 4 will be generated, and the oxide slag 4 will slide down the surface of the cavity 1-1 to the bottom of the cavity 1-1 and accumulate. At this time, the temperature of the rivet is very high and the plasticity is very good. The hardness is extremely low and it is easy to form. Therefore, the accumulated oxide slag 4 squeezes the surface of the rivet dome 3-1 and the bottom surface of the cavity 1-1 to form pits, and causes wear on the bottom surface of the cavity, not only It affects the riveting quality, riveting strength and appearance quality of the rivet, and also affects the quality of the rivet die, resulting in economic losses.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
