Loza E. Improvement of the theory of hot saws designing and equipment for their strengthening

The object of the investigation is hot saws for rolled stock. The objective of the investigation is to increase in service lives of discs of hot saws for rolled stock, due to elimination of crack formation inside teeth roots and reduction of crack formation in the areas of teeth spaces. Methods of investigation: of non-planar cross-sections, of determination of load carrying capacities of machine parts; methods of mathematical statistics and other. The scientific value: is in the better conception obtained for the mechanism of destruction of saws, a criterion for evaluation of discs' fatigue strength. It also includes scientific substantiation of the designed method, which prevent formation and development of fatigue cracks inside. For the first time, mathematical dependence between the depth of the strengthened layer along the sharp edge of the space between teeth, as the result of its deformation by a tool with conical shape and the strength of its depression and geometrical parameters of the space and deforming tool was determined. The practical value: method of choosing of rational dimensions of discs cutting sections and also modified profile of discs' teeth, a new design of the machine for strengthening of saws' discs. Implementation of the prepared designs in MP "Azovstal" allowed to reach total profit, amounting to 562200 UAH in two year. Application sphere is the production of rolled sections.