Controlling the effectiveness of the cutting process based on the analysis of the mass and size parameters of replaceable hard-alloy inserts

2020 ◽  
pp. 78-81
Author(s):  
B.Ya. Mokritskiy ◽  
D.A. Savinov ◽  
Ya.V. Konyuhova

The possibility of controlling the effectiveness of the cutting process taking into account the quality of replaceable inserts in high-precision machining of parts to prevent spindle imbalance and tool destruction with low quality of the inserts is considered. Keywords: cutting, replaceable insert, spindle, imbalance, machining accuracy. [email protected]

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 590
Author(s):  
Katerina Mouralova ◽  
Libor Benes ◽  
Josef Bednar ◽  
Radim Zahradnicek ◽  
Tomas Prokes ◽  
...  

Wire electrical discharge machining (WEDM) is an unconventional and very efficient technology for precision machining of the Nimonic C 263 super alloy, which is very widespread, especially in the energy, aerospace and automotive industries. Due to electrical discharge, defects in the form of cracks or burned cavities often occur on the machined surfaces, which negatively affect the correct functionality and service life of the manufactured components. To increase the efficiency of the machining of Nimonic C 263 using WEDM, in this study, extensive design of experiments was carried out, monitoring input factors in the form of machine parameters like Pulse off time, Gap voltage, Discharge current, Pulse on time and Wire feed, the output of which was comprehensive information about the behaviour of such machined surfaces, which allowed the optimization of the entire machining process. Thus, the optimization of the Cutting speed was performed in relation to the quality of the machined surface and the machining accuracy, as well as an analysis of the chemical composition of the machined surfaces and a detailed analysis of the lamella using a transmission electron microscope. A detailed study of the occurrence of surface or subsurface defects was also included. It was found that with the help of complex optimization tools, it is possible to significantly increase the efficiency of the machining of the Nimonic C 263 super alloy and achieve both financial savings in the form of shortened machine time and increasing the quality of machined surfaces.


2021 ◽  
Author(s):  
Taiyong Wang ◽  
Libo Cao ◽  
Yongbin Zhang ◽  
Jingchuan Dong ◽  
Songhui Jia ◽  
...  

Abstract In the field of CNC machining, high-speed and high-precision machining has been regarded as the key research by many scholars. In conventional methods, high-speed machining and high-precision machining are contradictory. It is inevitable to reduce the feedrate to improve the processing accuracy. In the paper, a pre-compensation based on discrete inverse transfer function (PDIT) theory is proposed. PDIT is able to improve machining accuracy by reducing contour errors without decreasing feedrate. The proposed PDIT theory is divided into three parts, NURBS interpolator, feedrate scheduling, and interpolator with pre-compensation. The NURBS interpolator has greatly advantage to interpolate the parameter curve directly. Therefore, the paper adopts the NURBS interpolator to accomplish interpolation. In the feedrate scheduling, S-type flexible acceleration and deceleration are used for path planning, and the maximum starting feedrate is obtained with the feedrate constraint. In the interpolator with pre-compensation, the NURBS interpolator is pre-compensated by PDIT. For inputs, the response of transfer function reach steady-state response with a little time. Before reaching steady-state response, the unsteady response exists in the transfer function. The unsteady response usually sustains tens of interpolation periods and must be lead contour error in machining. Hence, the PDIT theory is employed to compensate the contour error causing by the unsteady response of transfer function to NURBS interpolator. The drive system is a transfer function, so the unsteady response of drive system cause machining errors before reaching the steady-state response. In the paper, the NURBS interpolator is pre-compensated by PDIT theory before the drive system to reduce contour errors and improve machining accuracy. Finally, the performance of the proposed PDIT is evaluated by simulation experiments. The experimental results illustrate that PDIT theory obviously improve the machining accuracy and reduces the contour error.


2011 ◽  
Vol 381 ◽  
pp. 34-37
Author(s):  
Xi Zhang ◽  
Sheng Bao ◽  
Fang Cheng

The performance of a spindle is critical for high precision machining. In this paper, the spindle error motion in a high precision milling center was measured. The spindle is driven by air turbine with rotation speed of 120,000rpm. The radial and axial error motion of the axis of rotation was measured. The capacitive displacement sensors with nanometer resolution were mounted against the master gauge pin through the dedicated setup. Tlusty method was adopted to synchronize angular position of the spindle and data sampling. The measured radial and axial error motion of the spindle were 2.73μm and 2.59μm respectively. Despite of motion errors, the better machining accuracy still can be achieved. It seems that cutting force may improve the rotation performance of a spindle with aerostatic bearing.


2011 ◽  
Vol 201-203 ◽  
pp. 2334-2337 ◽  
Author(s):  
Zhi Qiang Zhang ◽  
Wen Jin Wang ◽  
Zhao Jian ◽  
Tai Yong Wang

The part’s surface quality of NC machining is influenced by the chord error greatly. The confined chord error algorithm for machining complex parametric surface is proposed for controlling the chord error. The arc length error is utilized to control the chord error of the interpolated point indirectly. The arc length error of interpolated point is computed by trapezia expressions, the coordinate and the first order derivative of interpolated point is computed by the interpolation algorithm. The computed error of confined chord error algorithm is discussed and the simulation indicate that the destined precision of the chord error can be satisfied by this algorithm.


Author(s):  
Jing Zhang ◽  
Jiexiong Ding ◽  
Qingzhao Li ◽  
Qicheng Ding ◽  
Zhong Jiang ◽  
...  

In the multi-axis high-speed and high-precision machining process, the contouring error and the feed rate of tool tip and affect the quality of machined workpiece and the processing efficiency, respectively. The faster feed motion will result in greater tracking error of each axis. The contouring error which directly affects the quality of machined part is caused by the tracking errors of the axes. Obviously, it is difficult to improve the contouring accuracy and increase the feed rate simultaneously. To this end, a novel optimization model is developed here based on the model predictive control method. First, the feed servo model of translational and rotary axes are established, and the contouring error model is afterwards constructed. Subsequently, the optimization algorithm is derived to achieve the high processing speed, and input constraints are addressed to avoid violation of the performance limitation of the drivers. In addition, contouring error constraint, which is obtained by calculating the contouring error of the processed path, is addressed to high contour accuracy. Finally, a simulation is conducted to verify the effectiveness and superiority of the proposed method.


Author(s):  
Jenny Niebsch ◽  
Ronny Ramlau

In high precision cutting processes it is very important to have a highly balanced system in order to produce components in optical quality. Achieving the best possible balancing state is a time consuming process. Therefor the prediction of the influence of the balancing state on the surface quality of the component is desirable. On the other hand such a prediction model should enable us to compute an objective necessary balancing state for a desired surface quality and thus save balancing time. In this article we present a model of an high precision cutting experimental platform that describes vibrations of the platform caused by imbalances and forces from the cutting process. To compute imbalances from vibrational measurements, regularizations techniques for the solution of inverse and ill-posed problems are employed and presented.


2014 ◽  
Vol 536-537 ◽  
pp. 1431-1434 ◽  
Author(s):  
Ying Zhu ◽  
Yin Cheng Zhang ◽  
Shun He Qi ◽  
Zhi Xiang

Based on the molecular dynamics (MD) theory, in this article, we made a simulation study on titanium nanometric cutting process at different cutting depths, and analyzed the changes of the cutting depth to the effects on the work piece morphology, system potential energy, cutting force and work piece temperature in this titanium nanometric cutting process. The results show that with the increase of the cutting depth, system potential energy, cutting force and work piece temperature will increase correspondingly while the surface quality of machined work piece will decrease.


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