Service HotlineThe history of screws was broadcast in 1986. Our country formulated a new standard for standard parts, which is commonly known as the new standard in the business. The most used ones are GB5780, GB5781, GB5782, GB5783, GB5784. GB5780 is a hexagonal head thick shank half-thread screw, its accuracy grade is C-grade product, which can be replaced by GB5782 (GB5782 is a hexagonal head thick shank full-thread screw, and its accuracy grade is grade A and B.) GB5781 is a hexagonal head full-thread screw. Threaded screw, the accuracy grade is C grade product. It can be replaced by GB5783 (GB5783 is a hexagonal head full-tooth screw, and its accuracy grades are A and B). GB5784 is a hexagon screw with thin rod and half teeth.
drilling and tapping screw, more specifically, refers to a drilling and tapping screw that can be closely connected to an object without clearance. Screws usually use a screw design to achieve the purpose of tightening, or adjusting distance, or moving or transmitting power. Among them, it is the most common for tightening, and the screws generally used for tightening also usually have The combined function of self-drilling, tapping and locking can achieve the purpose of its tight fit. Known drilling and tapping screws are such as
Gaskets are mechanical components used for cooperation between two objects, which play a role in preventing pressure, corrosion and leakage of pipes from natural thermal expansion and contraction between two objects. By using the gasket in conjunction with the bolt and nut, the gasket can increase the contact area between the bolt and nut and the metal parts, and play the role of buffering and shock absorption to prevent the thread from loosening.
Heat treatment broadcast quenching and tempering HB220-270, nitriding HRC>65 foreign use titanium carbide coating method to improve the corrosion resistance of the screw surface, but according to reports, its wear resistance is not good enough. A series of measures have been taken abroad to improve the wear resistance and corrosion resistance of the screw. One way is to use highly wear-resistant and corrosion-resistant alloy steel. Such as 34CrAlNi, 31CrMo12 and so on. There is also a method of spraying Xaloy alloy on the surface of the screw. This Xaloy alloy has high wear and corrosion resistance.
The conventional auger bit structure 1 includes a rod body 11, a screw head 12 provided on one end of the rod body 11, a drill tail 13 provided on the other end of the rod body 11, and a plurality of threads 14 arranged around the rod body 11; Wherein, the periphery of the drill tail 13 defines a parting line 15, and the parting line 15 makes the drill tail 13 symmetrically divided into a side 131 and a side 132, and a cutting end 133 is formed at the junction of the end of the side 131 and the end of the side 132, respectively. The cutting end 133 is concavely provided with a quarter-turn chip flute 134 in the same direction of the helix, and the edge 132 continues the chip flute 134 and has a quarter-turn chip flute 135 with different helical curvatures. , by connecting the chip groove 134 and the chip groove 135 through different helical curvatures, the drill tail 13 can form a symmetrical and complete chip groove of 188 degrees.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: B1170 hexagon slotted nuts, stud screws, blackened washers, pins, pins and other products, we can provide you with suitable products for you fastener solutions.
