Roll was some metal stock with a certain section of rolling tool, rolling and deformation of rational origin, to form the appropriate truncate parts Ting for a process.
Therefore, the hydraulic screw is a free chip plus d, rolling machine and its essence is using some of the material in the cold and the plasticity of Ding, rolling stock in limiting tools under the pressure of the plastic deformation, rolled to create thecorresponding thread.
Thread rolling process based on cold starting from 1831, as early as first use control wire feeder pickup roller bolt for fastening railway sleepers. However until 1940 before printing have not been widely used for precision thread rolling. Mainly inthe 19 century and beginning of 20th century, the stock material is not suitable forrolling. With billet pieces material mechanical performance of further improved, and precision hydraulic tool and process performance more high of roll silk machine of development success, roll silk machine thread of rolling processing technology get more big of universal, and wind can in carbon pigment sodium, and alloy steel (including stainless steel, and tool steel >, and bronze, and brass, and aluminum, and put, and drill, and nickel, and powder metallurgical and plastic, different billet pieces material Shang, on various type of parts (as taps, and engine anchor bolt and power borer tied, and spindle and screw thread, and hollow thin-walled pieces Shang thread,) All threads (including fine pitch thread) rolling.
In the process of hydraulic screw, is processing by extrusion billet metal rolling tool thread redistributed results.