The ferrule joint has the advantages of secure connection, high pressure resistance, temperature resistance, good sealing and repeatability, easy installation and maintenance, safe and reliable work, etc. The working principle of the ferrule joint is to insert the steel pipe into the ferrule, use the ferrule nut to lock it against the ferrule, cut into the pipe and seal it. It is connected to the steel pipe without welding, which is conducive to fire prevention, explosion protection and overhead work, and eliminates the disadvantages caused by inadvertent welding.