Racionalizace obrábění válce ze slinutého karbidu pro válcování drátu

Abstract

Master thesis is dealing with problems of difficult cutting hard materials specifically sintered carbide turning roll. The theoretical part are summarizes the hard materials, mechanical properties and precossing possibilities.Furthermore, the theoretical part mentioned possibilities of use of the materials for the turning inserts and finally is introduced roller for wire rolling, which is from WCCoNiCr materiál which is classic representative type of difficult hard materiál (sintered carbide). The practical part is dedicated to problematic machining WCCoNiCr roll of wire rod mill which is in the current technology is grinded. This technology is less productive compared to turning but indispensable for the production of rolls for rolling mill of prefininshing mill. Possibilities where replace grinding by turning emerges just prefininshing rolls of wire rod mill, which are less stringent tolerance requirements and roughness and composition of rod mill allows these rollers of prefinishing mill can be machine by turning. In the practical part are tested inserts of different kinds of CBN and examined their endurance and wear. Furhter, for evaulation of turning will be measured roughness, which must comply with the requirements prescribed in the drawing.