The Research On The Chip-Removing Interference In The Triangular Thread Turning

The non-free cutting is a cutting method which is widely existed in the current cutting machining, which contains the interference phenomenon of chip removal is the direct reason that causes the increasing of cutting force, temperature and cutting power consumption. For the problem that the current thread turning process of cutting power easily lead to the clamping deformation, this paper will focus on the chip-removing interference in the triangle thread cutting process, in order to reduce the degree of non-freedom and cutting force in the machining; meanwhile this will contribute to the increasing of the tool's innovative design. The main contents of this paper are as follows:First, this paper analyses the relation between static angle and dynamic angle of cutting tool by vector method, provides the tool grinding and the new deformation of chip removal interference model, which does the enough preparation for the cutting experiment and data analysis in later chapters.Second, from the perspective of force balance in the chip analyze oblique cutting model to obtain the relationship between cutting-force and shear force, determining the effect of unit cutting force of five control variables. through the experiment of cutting work-piece of 45# by the tools of HSS, and combined with the data analysis software of Eviews7.0 and nonlinear curve fitting software of 1st Opt to get the free cutting of the cutting ratio and main cutting force formula.Then, a conclusion that cutting edge inclination not only affects the direction of the flowing chip but also restrict the accuracy of tooth angle, by the analysis of thread turning path-equation; triangular threading tool under current conditions is impossible to achieve free cutting; established the main cutting-force model of thread tool in non-free cutting, through dividing the cutter unit; and put forward the concept of equivalent influence-coefficient and equivalent cutting-ratio, to help interference model simplification and solution.At last, through the thread cutting experiment and the software of 1st Opt to get the function model of the influence-coefficient and determine the main cutting force model of thread turning. And the average forecast error of this model is 24.16%. With the function, the paper has calculated and analyzed the non-free degree of experimental tool, and ultimately get the minimum non-free degree of the thread tool is 2.16 in the design of the cutting conditions, which of its normal rake angle and edge inclination are 10° and 5°. Under the condition of the same tooth angle, the tool can reduce 34.76% of the cutting force comparing with the tool whose longitudinal rake angle is 5°.