In terms of inner hexagon, there are two versions of the national standard, one is GB70-76, the 76-year version, and the other is GB70-85, the 85-year version, most of which implement the DIN912 standard, so you should pay attention to the difference in actual business operations: GB70 -85 completely coincides with DIN912, so there is no difference in the use of the new standard, mainly the difference between GB70-76 and DIN912: for M8 series hexagonal products, the diameter of the round head of GB70-76 is 12.5MM, It is smaller than 13.27MM of DIN912. For M10 series inner hexagon products, the round head diameter of GB70-76 is 15MM, which is smaller than 16.27 of DIN912. For M12 series inner hexagon, the round head diameter of GB70-76 is 18MM. It is smaller than the opposite side 18.27 of DIN912, and the round head diameter of the inner hexagon GB70-76 of M16 and M20 series is 0.33MM smaller than that of DIN912, which are 24MM and 30MM respectively. DIN912 is 24.33MM and 30.33MM respectively. In addition, the width of the inner hexagon between the old standard and the German standard is different due to different standards. The inner side of GB70-76 is smaller, and it should be paid attention to in business operations.
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.
At present, the commonly used shaft retaining rings in the market usually include elastic retaining rings and screw locking retaining rings, but they all require tools to be installed and disassembled, which is relatively inconvenient to use.
Guangdong Yueluo Hardware Industry Co., Ltd. involves a low-carbon steel rivet nut fastened to thin-walled and thin-plate fasteners, especially suitable for machinery manufacturing, automobiles, trains, aerospace, aviation, shipbuilding, construction, petroleum, textile, Fastening connection of instruments, furniture, electrical appliances and other equipment.
Among them, the pneumatic riveting machine is more commonly used. The pneumatic riveting machine is also equipped with a clamp for assembling the rivet. The existing clamp usually uses two rotating clamps for fastening and assembly, but the rotation easily causes the two clamps to buckle. Misalignment, thus affecting the assembly of the rivet.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: brass male screws, hexagonal extended nuts, 304 cap nuts, dish-shaped ingots and claw screw caps and other products, we can provide you with The right fastener solution for you.