Malkov

pp. 1-33

pp. 43-59

pp. 74-87

pp. 76-95

pp. 22-58

pp.44-59

Based on the developed geometrical model an experiment is conducted to calculate the values of tooth profile angles of thread milling cutter with helical flutes at variation of five factors in the established factorial space. When planning the experiment the full central composite draft has been elaborated in the coded form for five factors at three levels taking into account the orthogonality and the impossibility to conduct repeatedly experiments in the chosen points. Mathematical models are developed to calculate the tooth profile angles of thread milling cutter with helical flutes allowing to obtain the values of angles depending on a pitch of thread, a cutter diameter, a rake angle, an angle of lead of helical flutes, and a back angle. Calculation of the profile angles made according to polynoms for all combinations of factors has shown that an error of calculated values in comparison with the values obtained using a geometrical model do not exceed a tolerance for a half of tooth profile angle according to GOST 1336-77.

The paper presents a developed in CATIA V5 R17 software geometric model, allowing to determine the angles of the tooth profile of thread milling cutter with helical flutes. The model research has been conducted for geometric and design parameters of thread milling cutter, made of cemented carbide and high speed steel. It is established that available rake and clearance angles, and inclination angle of helical flutes at the accepted values of pitch and diameter of the tool lead to obtaining the angles of the tooth profile other than 30 degrees, thus requiring the calculation of angles β1 and β2 in each case of design. In the general case we have an asymmetrical profile with respect to the axis passing through the top of the tooth. The influence of geometrical and design parameters of the model on the values calculated angles is established.

This article presents a description of existent methods of correlation adjustment of tooth contour of thread milling cutters with straight flute. The author developed a method for profiling teeth of a thread milling cutting’s tapping unit with helical flutes and a face surface in the front section in the form of a line with a face angle which is not equal to 0°. Calculation showed that in a general case the thread milling cutter’s tooth contour for processing a metric thread is an unsymmetrical one with a deviation from 30 degrees which depends on the diameter of a tapping unit, a pitch of thread, an angle of slope of helical flutes and both end and front angles.

At designing  the tool on the basis of a carving-forming mill the basic attention is necessary to give it carving-forming to a part which influences accuracy of a profile of a cut carving.