Railway T thread screw

Bolts for Railway  According to relevant standards, bolt performance grades are divided into more than 10 grades such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. Among them, the bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenched, tempered).  They are generally called high-strength bolts, and the rest are generally called ordinary bolts. Production Process of the Railway Screw Spikes: Raw Material Wiredrawing Rod Cutting Head Forming Edge Cutting Thread Rolling Heating Treatment Surfa…