What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Metric threads are measured in MM (millimeters) and have a cusp angle of 60 degrees. Both US and Imperial threads are measured in inches. The cusp angle of the American thread is also 60 degrees, while the cusp angle of the imperial thread is 55 degrees. Due to the different units of measurement, the representation methods of various threads are also different. For example, M16-2X60 represents a metric thread. His specific meaning is that the nominal diameter of the screw is 16MM, the pitch is 2MM, and the length is 60MM. Another example: 1/4—20X3/4 means the inch thread, what he specifically means is the nominal diameter of the screw It is 1/4 inch (one inch = 25.4MM), there are 20 teeth on one inch, and the length is 3/4 inch. In addition, if you want to express American screws, UNC and UNF are usually added to the back of the British screws to distinguish between American coarse teeth or American fine teeth. In the usual domestic sales business, the most common standards we encounter are GB (National Standard) and DIN (German Standard). In the production of Yaoda, the following standards are mainly encountered: GB30; GB5783; GB5782; GB52; GB6170; GB818; GB819; GB845; GB846; GB70; DIN912; DIN933; It has been replaced by GB5783 (new national standard). GB52 (old national standard) has been replaced by GB6170 (new national standard) in the standard book.
The self-tapping locking screw is a series of coarse thread and ordinary thread, and the thread size is M3~M12mm. The threaded rod of the self-tapping locking screw is a thread with an arc-shaped triangular section. The screw is surface hardened and can be screwed into a prefabricated hole of black or non-ferrous metal material (which can be made by drilling, punching or die casting), and extruded to form an internal thread. The threaded rod portion can be made into a cylindrical or triangular shape with a diameter equal to or less than the circumscribed circle. Self-tapping locking screws have low screw-in torque and high locking performance. The varieties of self-tapping locking screws in the product standard of Chinese commodity fasteners include GB/T6560 (cross-recessed pan head), GB/T6561 (cross-recessed countersunk head), GB/T6562 (cross-recessed half-sunk head), GB/T6563 ( Hexagon head), GB/T6564 (hexagonal flower-shaped cylindrical head) five series. Self-tapping locking screws are generally fastened with pneumatic or electric screwdrivers. Most of the automotive industry uses hexagonal head, cross recessed pan head and hexagonal socket head self-tapping locking screw with high fastening efficiency.
The spring self-locking nut is a spring clip self-locking nut, which consists of an S-shaped spring clip and a self-locking nut. The S-shaped spring clip is provided with a fixing hole (3) for fixing the self-locking nut, which is used for the transition through the bolt. The self-locking nut is placed between the clamping hole and the transition hole (4), and is clamped in the clamping hole. The utility model adopts the elastic force of the spring clip to fix the self-locking nut on the connecting plate or the support. Not only is it convenient to install, but also has good reliability after installation.
In order to effectively improve the working efficiency of bearing installation when the equipment or device is being installed with flat pads, it is necessary to arrange the positions of the front and back of the flat pad.エ Time-consuming, labor-intensive, low production efficiency, high processing cost defects, at the same time, there is a shortage of unstable product quality, so the development of a flat pad front identification feeding mechanism has become a hot spot of industry research.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
