Theoretical considerations concerning the profile error of the thread flank

Laurenţiu Slătineanu,Traian Mihordea,Oana Dodun,Irina Beşliu Băncescu,Ionel Coman,Adrian Ghionea,L Slătineanu,M Boca,M Coteata,C.E Panait,R Ibanescu,M.I Ripanu,O Dodun,A.M Mihalache,V Merticaru,G Nagit

doi:10.1051/matecconf/201817801006

Abstract

In the case of metric thread, a possible source of the flank error could be the position of the cutting tool edge, which could not intersect the circular cylindrical surface axis. An analytical method of approximation was applied to model the way in which the flank error is generated by considering some geometrical conditions. A theoretical simplified model was determined to highlight the influence of the thread external diameter and of the distance between the circular cylindrical surface axis and the thread rectilinear generatrix on the profile error of thread flank.

Highlights

The threaded surfaces are surfaces obtained by moving a certain plane profile along a spiral
In the case of the metric threaded cylindrical surfaces, this profile could be approximated by an equilateral triangle that has a rounded corner
To diminish the value of the thread flank error, the plane corresponding to the equilateral triangle must be placed just in the plane of the axial section through the cylindrical threaded surface

Summary

Introduction

The threaded surfaces are surfaces obtained by moving a certain plane profile along a spiral. Koleva et al directed their research effort on the study of possibilities to compensate the errors generated by the mechanical deformation when machining threaded surfaces [4]. Aspects concerning the machining system capability to ensure the technological quality of the metric screw thread were studied by Zawada-Tomkiewicz and Wierucka [5] They developed a measuring system to evaluate some characteristics of a threaded surface, by means of an optical apparatus. They took into consideration the use of the proposed system to highlight the influence of the technological factors on the product quality. The results of a theoretical analysis of some factors able to affect the flank error in the case of obtaining threaded surfaces on lathes are discussed

Initial conditions

Theoretical flank error

Conclusions