Although there are many types of self-tapping screws, they all have the following common points: (1) They are generally made of carburized steel (accounting for 99% of the total output). Also available in stainless steel or non-ferrous metals. (2) The product must be heat treated. Carbon steel self-tapping screws must be carburized, and stainless steel self-tapping screws must be solution hardened. In order to make the self-tapping screw meet the mechanical properties and performance required by the standard. (3) The product has high surface hardness and good core toughness. That is, inner softness and outer rigidity. This is a major feature of the performance requirements of self-tapping screws. If the surface hardness is low, it cannot be screwed into the matrix; if the toughness of the core is poor, it will break as soon as it is screwed, and it cannot be used. Therefore, inner soft outer steel is a very important requirement for self-tapping screws to meet the performance requirements. (4) The surface of the product needs surface protection treatment, generally electroplating treatment. The surface of some products must be treated with phosphate (phosphating), such as wallboard self-tapping screws are mostly phosphated. (5) Produced by cold heading process. It is recommended to use high-speed cold heading machine and high-speed thread rolling machine or high-speed planetary thread rolling machine for production. The emphasis here is on high speed to ensure product quality. Only self-tapping screws produced by high-speed machines have well-formed heads and high-quality threads.
safety screw includes a screw rod, and is characterized in that: the two ends of the screw rod are respectively provided with notches for rotating a tool knife. Compared with the prior art, the advantage of Guangdong Yueluo Hardware Industry Co., Ltd. is that notches are provided at both ends of the screw, so that when the screw is in use, it can be tightened or loosened from both ends without installation. Due to the limitation of position and structure, when the installation space is small or the tool knife cannot be inserted, it is convenient for the operator to directly tighten or loosen the screw from the other end, which improves the efficiency of installation and disassembly, saves assembly time and reduces assembly difficulty.
Aiming at the shortcomings of the above-mentioned cabinets in the prior art that are assembled through hardware accessories, which affects the overall appearance, Yueluo provides a cabinet with a hidden screw-type installation structure and an assembling method thereof. The plate is fixed so that the screws can be hidden from the outside.
The pull-out type positioning pin and the tie-suspended type positioning pin are in the form of a straight cylindrical shape. The pull-out locating pin is temporarily pulled out from the connected piece of the tooling, and it is in a loose state; the tail of the tie-suspended locating pin is connected with a tie such as iron wire or string to the connecting piece of the tooling. After the locating pin is pulled out, the tie Suspended on tooling. The main disadvantages of the two types of positioning pins are as follows: First, the suspension straps are easy to fall off after long-term wear, and the pull-out positioning pins of the same parts are not convenient for on-site storage and placement, and are usually placed on the nearby ground at will; All kinds of positioning pins are prone to position transfer, forgetting and losing, which affects the reset of the tooling and the subsequent manufacture and assembly of aircraft products.
Equipment that needs to be maintained at high altitude or under complex working conditions requires screw loss prevention design. Although traditional captive screws can achieve the purpose of preventing falling off, because the diameter of the screw is smaller than the major diameter of the thread, it is difficult to match the gasket, and the gasket will be eccentric, which is easy to install. Scratch the surface of the product, affecting the corrosion resistance and appearance of the product.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: electrical nuts, limit bolts, fisheye washers, GB861 and other products, we can provide you with suitable fastener solutions for you.