SUMMARY
Kuhtinov Vladimir Mihailovich
Donetsk National Technical University
Mechanical Faculty
Specialiaty "Metallurgical equipment"
Research object in this work is the motor shaft of a blooming mill 950 as an element of the main line of a blooming mill. The attention rendered to this detail is explained by the fact that destruction of such details occurs extremely seldom, but their failures entails a stop of all blooming and, hence, significant expenses and idle time of shop. Therefore it is very important to analyse carefully this case and to draw corresponding conclusions on the reasons of failure under consideration. In turn, the knowledge of the reasons of destruction of the given concrete object is necessary to define, whether single or numerous refusals can take place on similar objects. This problem is especially actual because details and the equipment as a whole are unique, therefore their emergency refusal results in long idle time of blooming mill, and as a result, large expenses for restoration of serviceability.
The purpose of these researches consists in revealing the factors causing the tensely deformed condition of a motor shaft, an estimation of their influence degree, and also in a definition of the true reasons resulted in destruction of a motor shaft.
For achievement of an object in view it is necessary to solve a line of the following problems:
1) Visually to analyse character of a motor shaft destruction;
2) To define the forces influencing a shaft;
3) To execute mathematical modeling of the tensely deformed condition of a shaft in view of the revealed force factors, to estimate a degree of their influence.
Scientific novelty in this work is to reveal the factors causing the tensely deformed condition of a motor shaft, to estimate a degree of their influence on character of distribution strength in the shaft and to make a technical condition of a motor shaft, and also to define of their numerical values.
Practical use of results of these researches can be applied for prevention of emergency destruction’s of similar shaft by elimination of the factors promoting occurrence and development of fatigue cracks in details.
The review of researches existing at present and development was made in the following three directions: the review of the scientific and educational literature; the review of periodicals; the review of the helpful information in the Internet. As the helpful information three basic aspects of researches were considered: theoretical bases of calculations of the force factors working on shaft; methodology of carrying out of the analysis of refusals of shaft, including fatigue failures of motor shafts, and also mechanisms of origin and development of fatigue cracks in details of machines and various designs; mathematical modeling of the tensely-deformed condition of shaft with the help of a method of final elements from influence of various loading factors.
As a result of the researches that have been done the factors causing the tensely-deformed condition of a shaft of the engine will be revealed, the authentic picture of a degree of influence of each of these factors on character of distribution of strain a body of a shaft and a technical condition of a motor shaft as a whole will be.