Study On Structure And Manufacturing Of Carbide Drills With Indexable Inserts

With the improvement of the level of science and technology,the company have put forward higher requirements for the production efficiency and precision.After the wear of the carbide rotatable bit,it does not need to be re grind,and can be used after transposition.The processing efficiency is 2~3 times of the twist drill,the production cost is much lower than the twist drill and has the long life of the knife body.At present,this kind of cutting tool technology is not mature in China,and there is still a gap between the advanced level of foreign countries in some important indexes.It is mainly manifested in the uneven radial force during drilling,which leads to the low precision of the size of the drilling machining and the poor surface roughness.And the life of the blade is generally low.In this paper,the structure and manufacturing process of the hard alloy transposable bit are carried out from reducing the diameter direction force,improving the machining quality of the hole and optimizing the chip removal efficiency of the chip drain.Indexable drill include internal and external blades in general,cutting blade in the peripheral region responsible,responsible for cutting center area,due to asymmetric arrangement for blade,drill cutting blade cutting force and the external force to the back of the knife body superimposed on unbalanced radial force,the cutter body is elastically bent change,directly affect the machining hole diameter,the hole surface processing will also be a serious decline in quality,machine vibration and reduce the service life of the blade,and even lead to "tipping".In this paper,“S”stype blade as an example,a list of the installation parameters in the spatial arrangement of blades,impact on radial force,based on the theoretical calculation,through the correction of the actual drilling experiments,each retransposable bit,the most reasonable blade installation parameters,is gradually found.First,taking the S blade as an example,the influence of the blade space arrangement and installation parameters on the radial force is analyzed in this paper,.On the basis of the theoretical calculation,the method is corrected by the method of the actual drillingexperiment,which makes the bit in the drilling process the minimum deflection,or is produced along the cutting edge(sensitive)direction of the outer blade.The minimum deflection is found,and the most reasonable blade installation parameters for each indexable bit are found.Secondly,study on formation characteristics of drill in the processing chip,analysis of internal and external chip formation and morphology of the producing condition,and compared to similar products in the domestic groove,analyze the cause of failure reasons causing the blockage,knife body fracture,understand the advantages and disadvantages of each groove.To improve and optimize the structure of groove.Finally,based on the basic principle of heat treatment and the theory of thermal elastoplasticity,the finite element method is used to establish the analysis model of the heat treatment of the carbide relocated bit cutter body,and the DEFORM software is used to simulate the heat treatment process,and the size and direction of the blade deformation are analyzed,and the appropriate allowance is determined for the subsequent finishing process.In brief,through the research results of indexable drill,it has practical guiding significance for improving chip breaking and chip quality,improving workpiece surface processing quality,prolonging the service life of blade and blade,and machining efficiency in machining stage.