测量环境对珩磨气动测量精度影响的研究

发布时间：2018-04-17 18:31

本文选题：珩磨 + 气动测量　；参考：《兰州理工大学》2017年硕士论文

【摘要】：珩磨加工往往是零件的最终加工工序,所以珩磨效果好坏直接影响到产品的最终质量和使用性能。如今气动测量技术在珩磨加工中得到广泛应用,是因其具有测量精度高、测量稳定性好、自洁性好、不破坏被加工件表面质量等诸多优点,是组成珩磨机床闭环控制系统的重要环节。因珩磨机床气动测量系统的精度,直接影响到珩磨加工精度,进而影响到工件的质量。所以,通过分析研究测量环境因素,提升气动测量系统在珩磨机床中的测量精度显得尤为重要。相比于国外,我国珩磨机床在制造水平、加工精度、控制方式等方面都有较大差距,尤其是珩磨在线气动测量方面中仅仅起到开关比较作用,形状精度和表面质量只能在加工结束后下线测量。然而,气动测量系统不能为珩磨加工过程提供实时在线测量值,究其原因在于加工过程中测量结果受到测量环境的极大影响,气体需要在狭缝内冲破珩磨液与被珩工件表面碰撞,在狭缝内的气体射流情况复杂,珩磨加工区域中的珩磨液流量、温度、切削碎屑都会夹杂其中,对测量精度产生不同程度的影响。因此,气动测量系统不能为珩磨加工提供实时在线测量值,极大的制约了珩磨机床水平的发展。所以,通过研究珩磨加工区域测量环境中珩磨液温度、流量变化对气动测量精度的影响规律,为气动测量技术很好的应用于珩磨机床提供依据。本文在充分研究流体力学和气动测量的基础上,结合珩磨加工特点,首次提出了针对变换气路建立的差压式珩磨气动测量的动态数学模型;运用数值分析法,分析了珩磨头旋转状态下,珩磨液在狭缝内的运动情况;通过FLUENT仿真得到珩磨液温度变化和流速变化都会影响测量结果;根据需要,结合2MK2210型数控珩磨机床设计了气动测量正交实验,重点验证了外部环境因素中珩磨液流量、温度对测量精度影响的正确性,对实验数据的处理方式采用极差分析法,经过分析研究得到,在加工区域内测量环境中各影响因素对珩磨气动测量精度的影响规律以及其主次影响因素。
[Abstract]:Honing is often the final processing procedure of parts, so the honing effect directly affects the final quality and performance of products.Nowadays, pneumatic measurement technology has been widely used in honing, because it has many advantages, such as high measuring precision, good measurement stability, good self-cleaning, no damage to the surface quality of the workpiece, etc.It is an important link in the closed-loop control system of honing machine.The precision of the pneumatic measuring system of honing machine has a direct effect on the honing accuracy and the quality of the workpiece.Therefore, it is very important to improve the measurement accuracy of pneumatic measurement system in honing machine.Compared with foreign countries, the honing machine in our country has a big gap in manufacturing level, machining precision, control mode and so on, especially in honing on-line pneumatic measurement, which only plays a role of switching comparison.Shape accuracy and surface quality can only be measured offline after finishing.However, the pneumatic measurement system can not provide real time on-line measurement value for honing process. The reason is that the measurement results are greatly affected by the measuring environment.The gas needs to break through the honing fluid in the slit and collide with the surface of the honing workpiece. The gas jet in the slit is complicated. The honing fluid flow, temperature and cutting debris in the honing processing area are all mixed with each other.The measurement accuracy is affected in different degree.Therefore, the pneumatic measurement system can not provide real time on-line measurement value for honing processing, which greatly restricts the development of honing machine level.Therefore, by studying the influence of honing fluid temperature and flow rate on the precision of pneumatic measurement in honing processing area, this paper provides the basis for the application of pneumatic measurement technology to honing machine.Based on the full study of hydrodynamics and pneumatic measurement, the dynamic mathematical model of differential pressure honing pneumatic measurement is established for the first time in accordance with the characteristics of honing process, and the numerical analysis method is used.The motion of honing fluid in the slit is analyzed under the rotating state of honing head. The results of FLUENT simulation show that the change of temperature and velocity of honing fluid will affect the measurement results.Combined with 2MK2210 numerical control honing machine, the orthogonal pneumatic measurement experiment is designed, which mainly verifies the accuracy of honing fluid flow rate and temperature on measurement accuracy in external environmental factors. The range analysis method is used to deal with the experimental data.Through the analysis and study, it is found that the influence of various factors on the honing pneumatic measurement accuracy in the measuring environment in the machining area and its primary and secondary influence factors.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG806;TG580.68

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