This invention provides a kind of frictional etruder for rolling metallic tubings, especially is fit for production of the large diameter, highly precisionol thin-walled tubing or double layered metallic tubes. The features of this invention are to consolidate the sophisticated production processes of a modern continuous rolling tubing machine set into one extruder, with a structure of combinational memorial archway style, opposite attic extruding,provided with a main motor, full automatic fluid driving system, two alternately working explosively forming tube and splined cylinder, also with a reversely running motor in order enhance the number of revolutions and to change the temperature field. More outstandings are to break through the theory of hot rolling technology which holds for hundreds of years from theoretical ground, also the quality of grain refinement amount of the product theoretical ground, also the quality of grain refinement amount of the product and the quality of..... |