IMPACT OF LOCAL TECHNOLOGICAL CONCENTRATORS OF STRESSES UPON OPERATION PROPERTIES OF PARTS WORKED
Abstract and keywords
Abstract (English):
It is defined that during the machining of complex surfaces in parts operating under large fluctuating loads, in critical transition areas of profile conjugate surfaces there are formed local technological concentrators of stresses contributing to formation, development of fatigue cracks and to further destruction of parts in the course of operation. Such phenomena are discovered, for instance, at high-loaded gear teeth machining, at turbine blade profile surface machining, at manufacturing large-modular tapered threads and other parts having complex profile surfaces. There are developed and introduced methods for value decrease of such stress concentrators on the basis of the application of different methods for local surface plastic deformation of a surface layer in transition areas of profiles. As a result the probability of fatigue crack formation decreased considerably and fatigue strength in parts machined increased essentially.

Keywords:
stress technological concentrators, profile surface, local transition areas, fatigue strength, thread; gears, turbine blades.
Text
Publication text (PDF): Read Download
References

1. Makarov, V.F., Gorbunov, А.S. Resource and reliability increase in operation of spiral bevel gears by use of strengthening machining taking into account technological heredity influence // Proceedings of the Inter. Scientific Technical Conf. “Modern Science Intensive Technologies, Equipment and Tools in Mechanical Engineering”, S-PbTU, September 17-19, 2014г., pp. 369 - 378.

2. Gorbunov, А.S., Makarov, V.F. Influence of secuence in spiral bevel gear machining upon residual stress distribution and work hardening value of teeth surface layer // Engineering Technique. - 2012. - №3. - pp. 9 - 12.

3. Tamarkin, М.А. Theoretical Fundamentals in Optimization of Parts Treatment with Free Abrasives. D. Eng. Thesis. Rostov-upon-Don, 1995 г.

4. Papshev, D.D. Finishing- Strengthening Treatment by Surface Plastic Deformation. - М.: Mechanical Engineering, 1978. - pp. 152.

5. Poletayev, V.А., Volkov, D.I. Deep Grinding of Turbine Blades: technologist’s library. - М.: Mechanical Engineering, 2009. - pp. 272.

6. Nikitin, S.P. Theoretical investigation of stability at grinding // Bulletin of USATU. - 2013. - Vol. 17. - №8(61), - pp. 38 - 44.

7. Afonin, А.N., Kirichek, А.V. Deformation Schemes at Knurling. UDC 621.99 [Electgronic Resource]/ Access mode: http://www.google.ru/

8. Makarov, V.F., Nikitin, S.P. Influence of shaping conditions upon blade surface quality at deep profile grinding // Science Intensive Technologies in Mechanical Engineering. - 2015. - №8 (50). - pp. 38-44.

Login or Create
* Forgot password?