Bolt Quality: Nowadays, advanced manufacturing represented by large aircraft, large power generation equipment, automobiles, high-speed trains, large ships and large complete sets of equipment will enter an important development direction. As a result, fasteners will enter an important stage of development. High strength bolts are used for connection of important machinery. Repeated disassembly or various installation torque methods require high strength bolts. Therefore, the surface condition and thread accuracy will directly affect the service life and safety of the main engine. In order to improve the friction coefficient and avoid rusting, biting or jamming during use, the technical requirements stipulate that the surface should be treated by nickel-phosphorus plating. The thickness of the coating is guaranteed to be in the range of 0.02-0.03 mm. The coating is uniform, compact and without pinholes.
The bolt materials are 18Cr2Ni4W and 25Cr2MoV steel, and the bolt specifications are M27-M48. Because this kind of steel is easy to form a passivation film on the surface, and this passivation film will make bolts unable to obtain a good adhesion of chemical nickel and phosphorus layer, so special pretreatment measures must be taken to remove the film first, and measures should be taken to prevent its regeneration, in order to ensure a good adhesion between the plated coating and the matrix. At the same time, because of the large geometric size of the bolt, it is difficult to process nickel-phosphorus plating and quality detection.
High Stretch Structure Bolt
High Strength Hex Head Bolt Nut, Titanium Plating Bolt Nut, High Strength Hex Head Bolt,Heavy Hex Bolt High stretch structure bolt 1)Standard: ANSI 2)Grade: 5 , 8 3)Size: 1/4~1-1/2 length:1/2~9 4)Material:carbon steel, alloy steel.(35k,45#,40Cr,35CrMoA,42CrMoA) 5)Process:Cold heading/hot forging 6)Finish:black oxide, zinc plated (white Zinc,blue Zinc,color Zinc,white and blue Zinc,black Zinc),hot dip galvanized, Dacromet etc. 7)Packing:PE bag,carton. […]
Black Oxide Hex Bolt
High Strength Hex Head Bolts, High Strength Hex Head Bolt Nut, Titanium Plating Bolt Nut, High Strength Hex Head Bolt,Heavy Hex Bolt Specifications of Black Oxide Hex Bolt: Available Packing:Bulk in master cartons, then on pallets Certification: ISO, ROHS, SGS Sample:Free Port:Shanghai,Ningbo Black oxide hex bolt Material: Carbon Steel Standard: DIN GB ISO JIS BA […]