Research On Machining Method Of Slender Rod Including Thread

The slender shaft generally refers to the shaft with the aspect ratio L/d ? 25.It is widely used in the automotive,machine,hydraulic and other industries.For example,the screw of the machine tool and the piston rod of the hydraulic cylinder are all in the category of slender shaft.The smaller the diameter of the slender shaft and the longer the length,the more difficult it is to turn.This is because the slender shaft has poor rigidity and is susceptible to bending deformation and vibration under the action of gravity,cutting force and cutting heat,which makes machining accuracy and surface quality difficult to guarantee.At present,with the continuous development and upgrading of the mechanical equipment industry,the accuracy requirem ents of mechanical equipment for the slender shaft are generally improved.The research on the turning processing method of the slender shaft and the improvement of the turning precision and processing efficiency of the slender shaft have also become an important topic in the mechanical manufacturing process.According to the literature,the current research on this subject in China and abroad mainly focuses on theoretical analysis and mechanical analysis,and few Conduct formal test validation and provide test data.Experimental studies have been carried out in a small number of research results,but they are also limited to the cutting research of slender shafts with a length of less than 2500 mm,and less research on turning machining with the slender shafts longer than 6000 mm.In this paper,the turning machining of a threaded slender shaft with a shape of ?127mm×7000mm is studied.Through the theoretical analysis,the clamping method and lifting scheme of the threaded slender shaft were developed and the number and position of the lifting point and the clamping support point of the slender shaft are determined,which provides a theoretical basis to the lifting and clamping process scheme.And by adding auxiliary support,the process rigidity of the slender shaft during the turning process is enhanced,and the processing precision and processing efficiency of the slender shaft are improved.After the clamping support point is determined,the cutting parameters of the slender shaft,including the knife tool angle and the cutting am ount,are determined by the combination of the turning test and the theoretical verification,and the reference basis is provided for the cutting process of the same kind of slender shaft to select cutting parameters.In order to verify and optimize the above clamping method and cutting parameters,the turning test of the slender shaft is required.Before the formal test,the construction of the test platform is carried out,including the selection of the turning machine,the design of the center support fixture,the design of mechanical manufacturing process for threaded slender shaft and the design of the transition support fixture.The straightening method of the slender shaft was studied.The cutting parameters of the slender shaft were optimized by experiments.The cutting parameters of the end of the slender shaft were studied.The measuring method of the straightness of the slender shaft was studied.On this basis,the turning test of the threaded slender shaft was carried out and a set of processing methods for the threaded slender shaft is summarized,and the process of the workshop is standardized accordingly,which greatly improves the production efficiency and the pass rate of the product manufacturing,reduces the cost,and improves the competitive ability of the product in the market.