The Efficient Methods For NC Machining Of Complex Shape Natural Stones

Stone processing industry is an important part of China's manufacturing industries.China has become a big country in stone manufacturing and sales,and its output value and output are the first in the world.Natural stone with complex shape is favored by more and more people because of its unique shape,material and personalized characteristics.NC machining of complex shape natural stone is emerging as a new stone industry.Because of it has the appearance characteristics of complexity,irregularity and individuality,the complex shape natural stone has many problems during processing,such as difficulty in clamping,low clamping efficiency and poor clamping stability;And because of its high hardness,wear-resistant,brittleness and uneven material characteristics,resulting in a series of problems such as low CNC machining efficiency,tool wear fast and high processing cost.Therefore,the efficient methods of NC machining of complex shape natural stones is studied in this paper.The main contents are as follows:(1)Based on the analysis of the research status at home and abroad,the characteristics of natural stone with complex shape and its problems existing in NC machining are analyzed.First,the generation and classification of natural stone with complex shape are briefly introduced,and then whose appearance and material characteristics are analyzed.On this basis,three problems are pointed out in the process of NC machining of complex shape natural stones,namely,the clamping,the efficiency of NC machining and the processing benefits.(2)The efficient clamping methods for complex shape natural stones were studied.Based on the analysis of the characteristics of the complex shape natural stone and its clamping problems,a efficiency clamping method for complex shape natural stones is proposed in order to solve the problems of low efficiency,difficult positioning,poor clamping stability and poor adaptability during the changing parts.Including: The "232" clamping method composed of two support surfaces +three universal dynamic supports + two universal dynamic tensioners is proposed and the structure of the fixture is designed.Then the clamping process of the clamping fixture is analyzed,and force analysis of the main structure of the clamping fixture.Finally the clamping force of clamp is calculated.(3)The efficient processing methods for complex shape natural stones were studied.The cutting tool is one of the key factors which affect the processing efficiency and the processing benefit in the NC machining of the complex shape natural stones.Therefore,the selection factors of the cutting tool are analyzed first,and the method of selecting the NC machining tool for the complex shape natural stone is put forward.Then,according to the main factors affecting the cutting force and tool wear in the NC machining of natural stone,the process parameters and tool path selection methods in the NC machining process of complex shape natural stones are proposed.At last,an efficient processing method with multi-process combination of complex shape natural stone is proposed.(4)Taking the processing of the raw stone of Tuojiang jade as an example,the above method is applied to the Tuojiang jade processing,and the feasibility and practicability of the method are verified.The above methods have been applied in practice and provided technical support for enterprise processing,showing its good application prospects.