Round head three-combination screw The screw size in the round-head three-combination screw is GB818, and the main technical requirements of various types are: iron and stainless steel material requirements, iron low, medium, high carbon steel, stainless steel combination The materials of the screws are stainless steel 201, stainless steel 304 and stainless steel 316. The thread tolerance is 6G, and the mechanical properties of the iron combination screws are 4.8 and 8.8. The 4.8-level combination screws are ordinary steel, and the maximum allowable hardness is 255HV. The 8.8-level combination screws are generally made of wire rod 10B21. , and then undergo hardening treatment, and then dehydrogenation after hardening treatment. Hydrogen removal is to prevent hydrogen embrittlement of the spring washer in the combination screw. Prevent the spring pad from breaking. The tolerance class of the combination screws is A. The cross groove is H-shaped. The surface treatment of the combination screw has environmental protection and non-environmental protection. Such as, environmental protection blue zinc, environmental protection color zinc, black zinc, color zinc, white nickel and so on. The technical requirement of the combination screw for the spring washer is that the washer should be able to rotate automatically without falling off.
In order to prevent the waste of materials, those skilled in the art select steel wire as the processing material, and form an annular ring body by drawing the steel wire. Such as the announcement: CN103522009's invention name is a method of processing a retaining ring. The steel wire is used as the processing material, and the processing is carried out by drawing. After the steel wire is drawn and formed, annealing is performed. After the annealing is completed, the forming needs to bundle the steel wire. Since the cross section of the steel wire is rectangular, when it is drawn into the retaining ring base, the cross section changes due to the extrusion of the material, and the inner ring of the retaining ring base will be higher than the outer ring (forming a slope). The deformation is large. At this time, the punching of the opening of the retaining ring base body will produce a slump or cause greater material deformation; therefore, the retaining ring base body needs to be bundled. The bundling process is to prevent the material from being heated more during the quenching process. At the same time, it also has a certain adjustment effect during the quenching process, which makes the inclined surface smaller; but after the quenching is completed, the hardness of the retaining ring base increases, and the punching process for the upper opening will become more complicated.
(1) The surface rust, oil stains, burrs on the wall of the bolt holes, welding flashes, etc. should be cleaned up. (2) After the contact friction surface is treated, the specified anti-scratch coefficient requirements must be met. The high-strength bolts used should have matching nuts and washers, which should be used in accordance with the matching and should not be interchanged. (3) When the friction surface of the treated component is installed, it is not allowed to be stained with oil, soil and other sundries. (4) The friction surface of the module should be kept dry during installation and should not be operated in the rain. (5) Strictly check and correct the deformation of the connected steel plates before installation. (6) It is forbidden to hammer into the bolt during installation to prevent damage to the bolt thread. (7) The electric wrench, which is regularly tested during use, ensures the accuracy of the torque and operates in the correct tightening sequence. Main safety technical measures (1) The size of the wrench of the adjustable wrench should be consistent with the size of the nut, and the sleeve should not be added to the small wrench. A dead wrench should be used for high-altitude work. For example, when using an adjustable wrench, use a rope to fasten it, and people should fasten their seat belts. (2) When assembling the connecting bolts of steel components, it is strictly forbidden to insert your hands into the connecting surface or touch the screw holes. When picking and placing the bolster, your fingers should be placed on both sides of the bolster.
Nuts are a commonly used fastening parts and are widely used in various mechanical and electrical equipment. Common application equipment does not have particularly strict requirements on the anti-loosening properties of nuts, but for automobiles, high-speed railways, aerospace and nuclear power and other fields, many equipment or components work in a vibration environment for a long time, and it is easy to loose between bolts and nuts. This will affect the normal operation of the equipment and even cause safety accidents.
With the popularization of electrical equipment, the door cover that integrates the panel, the controller, the sealing and waterproof function and the appearance decoration has gradually been required for equipment matching. The head directly affects the appearance, and for kitchen equipment such as dishwashers, the fixing screws of the door cover are easily rusted in direct contact with the washing water, which urgently needs a door cover structure that is easy to disassemble but does not affect the appearance.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: set nuts, round nylon washers, welding bolts, national standard color metal bolts and other products, we can provide you with suitable fastener solutions for you Program.