What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Contents of the utility model The purpose of Guangdong Yueluo Hardware Industry Co., Ltd. is to provide a hexagon socket head screw that is easy to disassemble and assemble. In order to achieve the above purpose, the technical scheme adopted by the present invention is as follows: a hexagon socket screw, which includes a cylindrical screw head and a cylindrical screw below the screw head, the screw is provided with threads, and an integrated screw is designed between the screw head and the screw. The circular skirt pad has a hexagonal depression along the axial direction on the screw head, and is characterized in that two symmetrical flat grooves are opened on the upper part of the side wall of the hexagonal depression of the screw head, and the lines of the two flat grooves overlap. Guangdong Yueluo Hardware Industry Co., Ltd.'s socket head screws are compared with ordinary socket head screws. A notch is designed in the inner hexagon space at the top of the screw. In terms of tool use, it can be avoided that the socket head screws must be equipped with the corresponding socket head tools. disadvantages. The improved hexagon socket screw can not only use the matching hexagon socket tool, but also use the traditional flat-blade screwdriver, which is more convenient to use.
According to relevant standards, the performance grades of carbon steel and alloy steel bolts are divided into more than 10 grades such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. Among them, the bolts of grade 8.8 and above are made of low-carbon alloy steel or medium Carbon steel and heat treatment (quenching, tempering) are generally called high-strength bolts, and the rest are generally called ordinary bolts. The bolt performance grade label consists of two parts of numbers, which represent the nominal tensile strength value and yield ratio of the bolt material respectively. Stainless steel bolts are divided into A1-50, A1-70, A1-80, A2-50, A2-70, A2-80, A3-50, A3-70, A3-80, A4-50, A4-70, A4-80, A5-50, A5-70, A5-80, C1-50, C1-70, C1-110, C4-50, C4-70, C3-80, F1-45, F1- 60. The first letter and number represent the stainless steel group, and the second and third numbers represent 1/10 of the tensile strength. [2]
Spring washers are widely used in the load-bearing and non-load-bearing structures of general mechanical products. They are characterized by low cost and easy installation. They are suitable for parts with frequent assembly and disassembly. Quick and easy automatic selection of washers is included, but the anti-loosening ability of spring washers is very low! Especially in European and American countries that require high reliability, the adoption rate is extremely low, especially the important load-bearing structural connection parts have long been abandoned. Our country still has some applications in the military industry, but it has been improved to stainless steel. Steel spring washers have long been banned in CASC! It is also said to be very unsafe, because there are two reasons: 1 is circle rise and 2 is hydrogen embrittlement.
The utility model relates to a connecting piece, in particular to a female and female screw used for shaping products in interior decoration. In the current decoration project, when fixing the decoration stereotyped product, the process is complicated, so labor-intensive and time-consuming, the construction cost is high, and the construction degree is low. For example, the decorative board for fixing the wall, the main process step used in its operation is the leveling of the nail strip. That is to say, saw the wood to the required specifications, then draw horizontal and vertical lines on the wall, and then nail the wooden strips to the wall according to the horizontal and vertical lines, and then glue and glue the board. The first step is to install the lines, color and paint. It can be seen that it is quite troublesome to use the above method to construct. The purpose of Guangdong Yueluo Hardware Industry Co., Ltd. is to provide a female screw, which can skillfully connect decorative products to the wall. As conceived above, the technical solution of Guangdong Yueluo Hardware Industry Co., Ltd. is a female screw, which is characterized in that both ends of the screw are threaded, the screw-in end is screwed into the plastic expansion tube inserted into the wall, and the other end of the screw is threaded with the same A female piece is mated and connected. The other end of the screw can also be barb-shaped and directly fit with the decorative board. The screw thread of the screw-in end is a wood thread, and the thread of the mating connection end with the female part is a machine thread.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
