Fishtail bolts, also called rail joint screws, are mainly used in rail joint clamp connections to play a fastening role. Fishtail bolts are mostly used in track laying in metallurgy, coking, steel and other industries, and are used for connection fastening between rail and rail joints.
The commonly used materials of fishtail bolts are Q235 steel and 45# steel, 20 manganese titanium boron steel, 35CrMoA and other materials, which are divided into Pusong fishtail bolts and high-strength fishtail bolts according to the material. Usually the ordinary fishtail bolt is the square head of the top surface of the semi-circular sphere, the 8.8 high-strength fishtail bolt is added two circles of convex edges on the top surface of the semi-round ball at the square head, and the top surface of the square head of the 10.9 grade fishtail bolt is made into a flat cone table shape. Ordinary fishtail bolts are mostly Q235 material, high-strength fishtail bolts are made of 45# steel, 20 manganese titanium boron steel, 35CrMoA, 40 boron steel, etc.
The connection of ordinary fishtail bolts is transmitted by the shear resistance of the bolt rod and the pressure of the hole wall, and the pre-tension force is very small when tightening the nut; High-strength fishtail bolts transmit external forces by applying pre-tension and friction. The force characteristics of the two are different.
In general, ordinary crocodile tail bolts can be reused, while high-strength fishtail bolts cannot be reused and are mostly used in permanent connections. When in use, it is necessary to choose which kind of fishtail bolt according to the actual working conditions.