Some Problems and Treatment Suggestions in the Processing of Non-standard Equipment Parts of NC Mach

In the process of NC machine tool processing parts of non-standard equipment, problems such as sticking knife, burning knife and breaking knife often occur, which lead to bite of titanium alloy parts and lead to OVER-TOLERANCE or scrap of titanium alloy parts. In order to solve the problem of this kind of welding parts, the characteristics of titanium alloy materials, mechanical processing and cutting characteristics, selection of tool materials, milling processing characteristics, coolant and other aspects are analyzed, so as to improve the qualified rate of the first inspection of titanium alloy parts and to control the product quality of the parts well. In order to control the quality of products better, the cutting parameters of non-standard parts must be controlled well, and the processing characteristics of materials must be understood and mastered.

The air bearing spindle also has the advantages of good dynamic characteristics, long precision life, no vibration, rigidity/load value which is commensurate with the use conditions and so on. However, the spindle stiffness, calorific value and maintenance need to do meticulous work. In order to achieve nano-scale rotary accuracy of air bearing spindle, besides the shape accuracy of the air bearing shaft and sleeve reaching 0.15-0.2 um, and then through the homogenization of air film, it is necessary to maintain the uniformity of gas outflow from the air supply hole. The air flow uniformity on the bearing surface will be affected by the number of air holes, the distribution accuracy, the inclination to the axis, the convexity and concavity of the bearing, the cylindricity and the surface roughness of the welding parts. The non-uniformity of air flow is the direct cause of micro-vibration, which affects the accuracy of rotation. In order to improve the condition of gas supply system, porous material should be selected as bearing material.

The widespread application of NC machine tool parts processing for non-standard equipment promotes the development of cutting technology focusing on efficient turning of titanium alloy. For workshops that often process titanium alloy parts (especially expensive large aviation parts), a 50% increase in productivity is worth investing in special tool chucks and machine tools with high-pressure cooling systems. In order to reduce the cutting temperature, reduce the wear of crescent holes caused by it, and ultimately to use a higher feed rate and prolong tool life, it is to use a special form of high-pressure coolant. This kind of coolant not only has high pressure, but also presents a very accurate laminar jet shape. It can form a "water wedge" between the chip and the rake face of the blade to hold the chip up and minimize its contact with the rake face, thus avoiding crescent depression wear.