The trend in die/mold manufacturing at present is towards the hard machining at high speed to replace the electron dis- charge machining. Failure forms of the AlTiN-coated micro-grain carbide endmill when used for th...The trend in die/mold manufacturing at present is towards the hard machining at high speed to replace the electron dis- charge machining. Failure forms of the AlTiN-coated micro-grain carbide endmill when used for the machining of JIS SKD61 (HRC 53), a widely used material in die/mold manufacturing, are investigated. The endmill shows a characteristic that tool life decreases greatly due to the chipping when overload occurs or the rapid increase of wear when over-heat accumulation in cutting edges. As a consequence of the investigation, a strategy to regulate heat generation in the end milling process is proposed. This is accomplished by controlling the cutting arc length, i.e. the length of each flute engaging workpiece in a cutting cycle. Case studies on the slot end milling and comer rounding are conducted. The results show that the proposed strategy suggests the optimal tool path as well as the optimal pitch between successive tool paths under the cutting time criterion.展开更多
The core of computer numerical control(CNC) machine tool is the electrical system which controls and coordinates every part of CNC machine tool to complete processing tasks, so it is of great significance to strengthe...The core of computer numerical control(CNC) machine tool is the electrical system which controls and coordinates every part of CNC machine tool to complete processing tasks, so it is of great significance to strengthen the reliability of the electrical system. However, the electrical system is very complex due to many uncertain factors and dynamic stochastic characteristics when failure occurs. Therefore, the traditional fault tree analysis(FTA) method is not applicable. Bayesian network(BN) not only has a unique advantage to analyze nodes with multiply states in reliability analysis for complex systems, but also can solve the state explosion problem properly caused by Markov model when dealing with dynamic fault tree(DFT). In addition, the forward causal reasoning of BN can get the conditional probability distribution of the system under considering the uncertainty;the backward diagnosis reasoning of BN can recognize the weak links in system, so it is valuable for improving the system reliability.展开更多
For the electrical control system of XA6132 milling machine circuit complexity, reliability and flexibility, high failure rate. Mitsubishi FX2N-40MR programmable controller is used to improve the performance and effic...For the electrical control system of XA6132 milling machine circuit complexity, reliability and flexibility, high failure rate. Mitsubishi FX2N-40MR programmable controller is used to improve the performance and efficiency of the entire electrical control system by technological transformation. Mitsubishi FX2N-d0MRPLC on electrical control system transformation can expand link to the technological transformation of the similar equipments.展开更多
T68 boring machine electric control system circuit is complex, its reliability and flexibility is poor with high failure rate. The mitsubishi FX2N-40MR Programmable controller for the technical innovation of electric ...T68 boring machine electric control system circuit is complex, its reliability and flexibility is poor with high failure rate. The mitsubishi FX2N-40MR Programmable controller for the technical innovation of electric control system improves the work performance of the whole electric control system and the work efficiency. This paper introduces the mitsubishi FX2N-40MR PLC in T68 boring machine electric control system, the application of the elaborated system＇s hardware and PLC program design can provide work for technical reform of similar equipment.展开更多
In this work, the cutting forces by end milling operation are analyzed. Therefore, the main parameters of cutting force as cutting speed, feed rate and depth of cut also are investigated in our case. The cutting force...In this work, the cutting forces by end milling operation are analyzed. Therefore, the main parameters of cutting force as cutting speed, feed rate and depth of cut also are investigated in our case. The cutting force is modelled and analyzed into mathematical Wolfram simulations in order to compare the results and in the same time achieve the best solutions. Theoretical results are carried out by using the regression method that required fulfilling the critter by Fisher. The number of experiment, measurements and results of cutting force are presented in 2D as well as 3D. In order to verify the accuracy of the 2D diagram, the results for our case is used both two way such as experimental and theoretical method as well as results are compared. In other hands, these results indicate directly that the optimized parameters are capable of machining the workpiece. The obtained measurement results are compared with theoretical methods in Wolfram software.展开更多
文摘The trend in die/mold manufacturing at present is towards the hard machining at high speed to replace the electron dis- charge machining. Failure forms of the AlTiN-coated micro-grain carbide endmill when used for the machining of JIS SKD61 (HRC 53), a widely used material in die/mold manufacturing, are investigated. The endmill shows a characteristic that tool life decreases greatly due to the chipping when overload occurs or the rapid increase of wear when over-heat accumulation in cutting edges. As a consequence of the investigation, a strategy to regulate heat generation in the end milling process is proposed. This is accomplished by controlling the cutting arc length, i.e. the length of each flute engaging workpiece in a cutting cycle. Case studies on the slot end milling and comer rounding are conducted. The results show that the proposed strategy suggests the optimal tool path as well as the optimal pitch between successive tool paths under the cutting time criterion.
基金the National Science and Technology Major Project of China(No.2014ZX04014-011)
文摘The core of computer numerical control(CNC) machine tool is the electrical system which controls and coordinates every part of CNC machine tool to complete processing tasks, so it is of great significance to strengthen the reliability of the electrical system. However, the electrical system is very complex due to many uncertain factors and dynamic stochastic characteristics when failure occurs. Therefore, the traditional fault tree analysis(FTA) method is not applicable. Bayesian network(BN) not only has a unique advantage to analyze nodes with multiply states in reliability analysis for complex systems, but also can solve the state explosion problem properly caused by Markov model when dealing with dynamic fault tree(DFT). In addition, the forward causal reasoning of BN can get the conditional probability distribution of the system under considering the uncertainty;the backward diagnosis reasoning of BN can recognize the weak links in system, so it is valuable for improving the system reliability.
基金supported by the Hubei Province Education Science "Twelfth Five Year Plan" 2013 annual research topic,No.2013B298
文摘For the electrical control system of XA6132 milling machine circuit complexity, reliability and flexibility, high failure rate. Mitsubishi FX2N-40MR programmable controller is used to improve the performance and efficiency of the entire electrical control system by technological transformation. Mitsubishi FX2N-d0MRPLC on electrical control system transformation can expand link to the technological transformation of the similar equipments.
基金supported by Hubei Province Education Science"Twelfth Five Year Plan"2013 Annual Research Topic,No.2013B298
文摘T68 boring machine electric control system circuit is complex, its reliability and flexibility is poor with high failure rate. The mitsubishi FX2N-40MR Programmable controller for the technical innovation of electric control system improves the work performance of the whole electric control system and the work efficiency. This paper introduces the mitsubishi FX2N-40MR PLC in T68 boring machine electric control system, the application of the elaborated system＇s hardware and PLC program design can provide work for technical reform of similar equipment.
文摘In this work, the cutting forces by end milling operation are analyzed. Therefore, the main parameters of cutting force as cutting speed, feed rate and depth of cut also are investigated in our case. The cutting force is modelled and analyzed into mathematical Wolfram simulations in order to compare the results and in the same time achieve the best solutions. Theoretical results are carried out by using the regression method that required fulfilling the critter by Fisher. The number of experiment, measurements and results of cutting force are presented in 2D as well as 3D. In order to verify the accuracy of the 2D diagram, the results for our case is used both two way such as experimental and theoretical method as well as results are compared. In other hands, these results indicate directly that the optimized parameters are capable of machining the workpiece. The obtained measurement results are compared with theoretical methods in Wolfram software.
