Oleh Onysko* , Tetiana Lukan, Lolita Pituley, Iryna Shuliar , Yurii Havryliv 

1 Ivano-Frankivsk National Technical University of Oil and Gas, Vulytsya Karpatsʹka, 15, 76000 Ivano-Frankivsk, UA, onysko.oleg@gmail.com, lutana.ua@gmail.com, lolitapituley@gmail.com, ira.shuliar@gmail.com, meson1959@gmail.com


ISSN 2637-2150 
e-ISSN 2637-2614 
UDK 531.3:[005.5:658.11(4-672EU)  
DOI 10.7251/STED0220022O

Paper received: 06.10.2020. 
Paper accepted: 17.11.2020. 
Published: 30.11.2020. 

Corresponding Author: 
Oleh Onysko, Ivano-Frankivsk National Technical University of Oil and Gas, Vulytsya Karpatsʹka, 15, 76000 IvanoFrankivsk, UA, onysko.oleg@gmail.com.


Many modern threaded joints, especially in the oil and gas industry, must satisfy high requirements for steel mechanical properties of which they are made. To ensure efficient threading of such hard-to-machine materials (ultimate strength is more than 1250 MPa), it is necessary to use carbide cutting inserts with the negative rake angle at its corner. However, modern manufacturers of such inserts make them only with a zero value of the rake angle. This is due to the difficulty of profiling of the insert cutting edge. This article proposes the basics of such inserts automatic profiling which is based on the algorithm developed by the authors. It includes two corrective calculations of the insert cutting edge profile, namely: the radial displacement of the corner and the tangential displacement of the area forming the crest of the thread. As a result, the computer application with the input parameter of the rake angle and output parameter of the upgraded profile of the insert cutting edge is received. 

Keywords: profile of the cutting edge, negative rake angle, machining of thread.