Factors of Microdrift of Piece Surfaces in Mechanical Processing

Abstract

Background. The article considers the aspects of an actual problem of research of factors of accuracy loss of exact piece manufacturing by mechanical processing in conditions of serial and mass production, in particular occurrence of a piece surface microdrift during processing that leads to the accuracy control function loss of shaping parameters. Objective. The aim of the paper is to create an analytical model for controlling the dimensions of a batch of pieces, which can be the basis for recommendations for the further development of instrumentation for operation in mass production. Methods. A model for changing the technological process parameters referring turning machining) is proposed, which can be regarded as a single discrete sample with a single piece taken. It is shown that the geometric dimensions have a parallel transfer in time from one piece to another. This approach allows us to consider a single discrete sample with respect to the piece in question, as a completed definite function for a separate study. Results. It is proved that with this approach to the process consideration the main components that influence the formation of the required dimension are taken into account. The components that influence piece dimensions are shown. A model for the appearance of a temperature drift of the piece surface and the effect on the accuracy of working out the surface coordinate is proposed. Conclusions. The model for taking into account the piece surface microdrift is proposed, which arises from the difference between the absolute and local coordinates of the object. Further studies should be aimed at identifying the design features of the measuring transducers, which also allow for the presence of the surface microdrift of the technological object. Thus, the principles of constructing the basic types of the design of measuring heads will be justified taking into account the location of process objects in the working space of the metalworking machine in measuring the physical properties of certain specific local area of the workpiece surface (or finished part).

Keywords

• Microdrift
• Mechanical processing
• Piece surface
• Temperature drift
• Mass production