Service HotlineWhen the countersunk head screws and hexagon socket head bolts are produced by the cold heading process, the original structure of the steel will directly affect the forming ability of the cold heading process. In the process of cold heading, the plastic deformation of the local area can reach 60%-80%, so the steel must have good plasticity. When the chemical composition of the steel is constant, the metallographic structure is the key factor to determine the plasticity. It is generally believed that the coarse flaky pearlite is not conducive to cold heading forming, while the fine spherical pearlite can significantly improve the plastic deformation ability of the steel. For medium carbon steel and medium carbon alloy steel with a large amount of high-strength bolts, spheroidizing (softening) annealing is performed before cold heading, so as to obtain uniform and fine spheroidized pearlite to better meet the actual production needs. For the softening annealing of medium carbon steel wire rods, the heating temperature should be kept above and below the critical point of the steel, and the heating temperature should not be too high, otherwise tertiary cementite will precipitate along the grain boundary, resulting in cold heading cracking. The wire rod of medium carbon alloy steel is annealed by isothermal spheroidization. After heating at AC1+ (20-30%), the furnace is cooled to slightly lower than Ar1, the temperature is about 700 degrees Celsius for an isothermal period, and then the furnace is cooled to about 500 degrees Celsius and air-cooled. The metallographic structure of the steel changes from coarse to fine, from flake to spherical, and the cracking rate of cold heading will be greatly reduced. The general area of softening annealing temperature for 35\45\ML35\SWRCH35K steel is 715-735 degrees Celsius; while the general heating temperature for spheroidizing annealing of SCM435\40Cr\SCR435 steel is 740-770 degrees Celsius, and the isothermal temperature is 680-700 degrees Celsius.
Principles of stainless steel screw material selection: The selection of stainless steel materials is mainly considered from the following five aspects. 1. Requirements on mechanical properties, especially strength, of stainless steel screw materials; 2. Requirements on corrosion resistance of materials by working conditions; 3. Heat resistance of materials by working temperature (high temperature strength, oxidation resistance) 4. Requirements for material processing performance in terms of production technology; 5. Other aspects such as weight, price, procurement and many other factors must be considered.
As we all know, whether it is the necessities in people's life or the equipment in industrial production, there will be a structure of screws and screw holes on it. This kind of structure that can simply fix some components together has been widely used in various fields. For the installation and removal of screws, people invented manual screwdrivers, and then to electric screwdrivers and so on. For manual screwdrivers, the operator needs to manually install or remove the screws. When encountering small screws, it can still handle it. When encountering large screws, due to people's limited strength, they may not install the screws in place, so it was invented. Electric screw. When installing the screw, which is widely used in the market, the operator needs to hold the screw handle, fix the screw on the screw port, and then align the screw with the corresponding screw hole for screwing. The disadvantage of this kind of screw is that it is heavy in quality and laborious to operate, and secondly, the operator will be injured due to operating errors, and the consequences are extremely serious. In view of this deficiency, people fix the screws on a work frame, so that before installing the screws, the operator only needs to adjust the screws to the designated position, and then the screws can be installed, which is convenient and simple. However, there are still potential safety hazards. In the process of adjusting the screw, it is still possible that the power of the screw may be turned on by mistake due to operating errors, resulting in injury to the operator. In view of the above-mentioned defects, it is necessary to invent a screw installation method with an anti-missing function.
The technical solution adopted by Yueluo to solve its technical problems is: a cabinet with a hidden screw type installation structure. The cabinet includes corner fittings, frame profiles and plates. Connecting slot, the plate installation slot is U shaped, the plate installation slot on the frame profile can be set with one or two, the insertion slot is located on the inner side of the plate installation slot; the main body of the corner fitting is fixed in three directions. The plug connector, the outer side of the plug connector is provided with auxiliary plate installation grooves, and the auxiliary plate installation groove is provided with side baffles; the plug connectors on the corner fittings are correspondingly inserted into the plug connectors on the frame profile, and the cross section of the plug connector Consistent with the cross-sectional size of the corresponding insertion slot, the plate is inserted between the plate installation slots on the frame profile.
Pin riveting is an important procedure in the production process. At first, people used manual work, which has low production efficiency, high production cost, and high defect rate of products produced. Later, a pin riveting machine appeared. The pin riveting machine is a For riveting and pinning of hardware products, the pin riveting machine can complete the operation of pin loading and riveting pins, and the pin riveting machine reduces the process of pin loading and riveting pins in the hardware production process. However, its structural design is unreasonable and the operation is very inconvenient
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: gypsum board expansion screws, flat gasket materials, black cross countersunk head machine screws, nylon studs and other products, we can provide you with suitable products Your fastener solution.
