Affiliation:
1. FSBEI HE Nosov Magnitogorsk State Technical University
2. OJSC MMK-Metiz
Abstract
The paper compares the technical characteristics of two thermochemical treatment (TCT) lines for self-tapping screws at OJSC MMK-Metiz. Quenching on TCT line 1 is carried out in the furnace by AUTOMATION SERVICE, while quenching on TCT line 2 is carried out in the furnace by KOHNLE. The authors described quenching and tempering schedules in these two furnaces, studied the microstructure of screws at all process stages, determined technical parameters and properties of finished products after thermochemical treatment. The research showed that the best performance had TCT 2 by KOHNLE. The metallographic analysis indicated more stable parameters of the layer thickness after nitrocarburizing, core and surface hardness, which was in full compliance with regulatory documents. By introducing a better structure of a new TCT line by KOHNLE, a TCT process period became shorter, and a range of self-tapping screws might be extended entailing a higher output of finished products.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
Reference20 articles.
1. V.V. Chukin, V.I. Artyukhin, G.Sh. Rubin et al., The problem of improving the quality of fasteners, Vestnik of Nosov Magnitogorsk State Technical University. 4 (2007) 99-102.
2. A.A. Filippov, G.V. Pachurin, Development priorities of producing high-strength fasteners, International Journal of Applied and Basic Research. 8 (4) (2014) 30-36.
3. A.D. Nosov, V.V. Chukin, A.A. Sokolov, E.N. Guseva, F.T. Fakhitova, Features of the thermochemical treatment process for self-tapping screws at OJSC MMK-METIZ, Vestnik of Nosov Magnitogorsk State Technical University. 2(22) (2008) 64-65.
4. Technical Specifications TU 1640-041-00187240-13. Self-Tapping Screws.
5. echnical Specifications TU 25.94.11-172-00187240-2017. Rounded-Off Pan-Head Self-Tapping Screws.