XK715Type Vertical CNC Milling Machine Spindle System Heat Transfer Characteristics Research

With the development of machining went into the automation and higher precisionprocess, The demand for computer numerical control machine tools also get higher. Hotstate characteristics of NC machine tools just like static characteristics, dynamiccharacteristics of NC machine tools has become a very important feature. Machine tools inthe machining process under the influence of internal and external heat source(such ascutting heat, bearing heating and thermal radiation, etc), It will cause the machine toproduce hot deformation, one of the biggest impact is the spindle system. If Spindle hassevere thermal deformation, it will directly affect the machining accuracy of machine tools.According to the research, the thermal deformation caused by manufacturing errorsaccounting for40%~70%of total manufacturing error, so the effects of thermaldeformation to the machining accuracy must be taken seriously. In order to solve theproblem caused by the thermal deformation of the manufacturing error first need toimprove hot state characteristics of the machine tool spindle system. This article first usethe CAD software to establish the spindle model, then make a steady state thermal-structure coupling analysis on the ANSYS, to get the spindle temperature field distributionand thermal deformation results. After established the model of spindle system, then theXK715type vertical CNC milling machine with cooling system is to carry on the ANSYStransient thermal-structure coupling analysis. Contrapose at the influence law of differentparameters on the main shaft system put forward methods to improve the hot statecharacteristics of machine tool spindle system.The results of the thesis research:(1) According to ANSYS to steady state thermal-structure coupling analysis of thespindle, learned that the front and the back of the main shaft bearing of calorific value andthe thermal deformation were very bigger, provides the evaluation index system toimprove the spindle thermal state characteristic.(2) After establishing XK715type vertical CNC milling machine spindle systemmodel, then carry on the ANSYS transient thermal-structure coupling analysis on it.According to the cooling process in various parameters(such as the cooling watertemperature, cooling water flow rate, water tank volume and coefficient of heat transfer)to compare the effects for hot state characteristics of spindle system. By comparing theseparameters to analysis their respective influence law, then improve the hot statecharacteristics of the spindle system to provide relevant advice. Papers through the thermal analysis study of NC machine tool spindle system, for themachine design personnel in the spindle system of cooling process provide theoreticalsuggestions, on the other hand, it is also put forward the requirements for the futurefollow-up study.