The 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.
Most of the existing screws use an integral metal structure, and there are still some problems, such as large weight, high cost of materials, wear resistance, hardness, rust resistance, corrosion resistance, high and low temperature resistance, brittleness, toughness, etc. Many occasions cannot meet the needs of production, and further improvements are needed to improve production efficiency, reduce costs, improve safety, and prolong the service life of screws.
Many existing products need to use screws in the production process, especially in the field of nuclear power sluice gates, it is necessary to fill a part of the sluice gate with screws to fix the size and structure. If the fixing effect is not good, then It will lead to more leakage of water gates, waste a lot of water resources, and even cause safety accidents.
⑥ Surface Treatment Zn: White Zinc C: Color Zinc B: Blue Zinc F: Black Zinc O: Black Oxide Ni: Nickel Cu: Bronze Br: Red Copper P: Phosphating
Standard introduction Standard code name Material coating GB/T65-2000 slotted cylindrical head screw steel, stainless steel galvanized passivated or untreated GB/T67-2000 slotted pan head screw steel, stainless steel galvanized passivated or not Treated GB/T68-2000 slotted countersunk head screw steel, stainless steel galvanized passivated or untreated GB/T70.1-2008 hexagon socket head screw steel, stainless steel galvanized passivated or untreated GB/T70 .2-2008 Hexagon socket head screw steel, stainless steel galvanized passivated or untreated GB/T70.3-2000 Hexagon socket head countersunk head screw steel, stainless steel galvanized passivated or untreated GB/T71-1985 Open Slotted taper end set screw steel, stainless steel galvanized passivated or untreated GB/T73-1985 slotted flat end set screw steel, stainless steel galvanized passivated or untreated GB/T74-1985 slotted concave end set screw Screw steel, stainless steel galvanized passivated or untreated GB/T75-1985 slotted long cylindrical end set screw steel, stainless steel galvanized passivated or untreated GB/T77-2000 hexagon socket flat end set screw steel, stainless steel Galvanized passivated or untreated GB/T78-2007 Hexagon socket set screw steel, stainless steel galvanized passivated or untreated GB/T79- 2000 Hexagon socket set screw steel, stainless steel galvanized passivated Or untreated GB/T80-2007 Hexagon socket set screw steel, stainless steel galvanized passivated or untreated GB/T818-2000 Cross recessed pan head screw steel, stainless steel galvanized passivated or untreated GB/ T819.1- 2000 Cross recessed countersunk head screw steel 4.8 grade steel galvanized passivation GB/T819.2- 1997 Cross recessed countersunk head screw steel, stainless steel A2-70, non-ferrous metal CU2 or CU3 steel, stainless steel or non-ferrous metal plated Zinc passivated or untreated GB/T820- 2000 Cross recessed half countersunk head screw steel, stainless steel galvanized passivated or untreated GB/T822- 2000 Cross recessed cylinder head screw steel, stainless steel galvanized passivated or untreated Treated GB/T823-1988 cross recessed small pan head screw steel, stainless steel galvanized passivated or untreated GB/T833-1988 slotted large cylindrical head screw steel, stainless steel galvanized passivated or untreated GB/ T837- 1988 Slotted pan head non-prolapse screw steel, stainless steel galvanized passivated or untreated GB/T838- 1988 Hexagon head non-prolapse screw steel, stainless steel galvanized passivated or untreated GB/T2671.1- 2004 Hexagon socket head low cylindrical head screw GB/T2671.2-2004 Hexagon socket head screw GB/T2672-2004 Hexagon socket head pan head screw steel galvanized passivation GB/T2673-1986 Hexagon socket countersunk head screw steel plated Zinc passivation GB/T13806.1-1992 Fasteners for precision machinery ten Slotted Screws Steel, Copper: H68 or HP59-1 Zinc Passivated or Untreated
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: supporting combination bolts, GB5782 screws, claw screws, spring pin cotter pins and other products, we can provide you with suitable fasteners for you solution.