With the development of manufacturing industry, more and more parts are processed by precision CNC lathes. This kind of high-efficiency and high-precision equipment can process rotating parts such as shafts, discs and sleeves, and can automatically complete the cutting and processing of internal and external cylindrical surfaces, conical surfaces, circular arcs, threads and other processes through program control, and carry out grooving, drilling, expanding, reaming and other work. The precision CNC lathe is controlled by software. It is the key to ensure the normal operation of the CNC machine tool. Once a certain parameter is lost or wrongly changed, it is easy to make some functions of the machine tool impossible to be realized or the system chaotic or even paralyzed.
(1) Programming error: mainly refers to the interpolation error generated by the NC system during NC programming, which is mainly caused by using the straight line segment or arc segment to avoid the contour of the part. This is an important factor affecting the machining accuracy of parts. It can be solved by increasing the number of interpolation nodes, but it will increase the programming workload.
(2) Tool tip arc error: when cutting inner hole, external cause or end face, the tool tip arc does not affect its size and shape, but it causes over cutting or less cutting due to the influence of tool tip arc when machining conical surface or arc. This error can be eliminated by measuring the arc radius of the tool tip and using the tool radius compensation function.
(3) Measurement error: it is mainly caused by the measurement accuracy of the measuring tool and the operation method of the measurer, resulting in the inaccuracy of the measured dimension. This error can be compensated.
(4) Tool setting error: this error mainly occurs in the tool setting process. When the tool moves to the starting point, it is affected by the feed adjustment proportional value of the operating system. The solution is to reasonably select the feed adjustment proportion, especially when the tool is close to the starting point position, the minimum gear feed adjustment is adopted to make the tool accurately locate at the starting point position.
(5) Machine tool system error: the geometric tolerance caused by the influence of the machine tool body, which is generally not adjustable; The repeated positioning error produced by the servo unit and the driving device is mainly affected by the pulse equivalent size, uniformity and transmission route of the machine tool; These errors are small and stable, and should be considered only in precision machining.
