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Abstract

Content

Introduction

Gears are one of the most widely used parts of gears, gearboxes, drive mechanisms, pumps and other equipment, the elements of which rotate.

The service life of construction, loading and unloading, earthmoving, agricultural, mining, forging and other machines is very limited.

In most cases, these machines are equipped with gears having gears of a relatively large module.

Gears are, and will remain in the foreseeable future, one of the main transmission elements of most known types of machine assemblies.

A gear transmission as a product of production is a knowledge-intensive, material-intensive and labor-intensive product. The main share (85.90%) of the failure of machine parts and assemblies is due to wear and tear and fatigue damage. A special place is occupied by sudden gear failures, such as: breakages and chipped teeth, which are often the result of a sudden stop of the operation of the machine, lead to an emergency and require an increase in repair costs. Moreover, the repair and maintenance of the machinery fleet requires 4. 10 times more funds and materials than manufacturing. Therefore, improving the quality and efficiency of the manufacture and repair of gears is one of the most important tasks for the entire engineering complex.

The solution to this problem can be carried out, both within the framework of existing technologies, and by searching for new solutions.

It is important to develop research methods for heavily loaded friction units – gears, widely used in machine assemblies, to create their stable operational characteristics.

In this regard, it was necessary in the current conditions of market relations to find an area where heavily loaded large-modular gears are regularly and in large quantities, statistics on the time of their operation are kept, the overhaul periods of their operation are determined and recorded, as well as the possibility of widespread introduction of gears wheels made using new technology. In this regard, we selected railway enterprises of the Ministry of Transport of the Russian Federation for implementation. So, according to the data received from the department of the Ministry of Transport of the Russian Federation that processes statistical data, for the nine months of 2003, 1,677 gear wheels of traction gearboxes of electric trains failed.

We associate the provision of increasing the reliability and durability of the gear transmission with the use of surface plastic deformation (PPD) treatment, with the simultaneous hardening of involutes and cavities between the teeth.

A major contribution to the theoretical justification of the RPM process and other methods of hardening various machine parts was made by scientists: P. G. Alekseev, B. M. Astashkevich, A. P. Babichev, M. A. Balter, V. M. Braslavsky, N. A Boucher, A. M. Dalsky, Yu. V. Dimov, M. S. Drozd, D. G. Evseev, M. A. Elizavetin, M. M. Zhasminov, NLKh Zobnin, V. G. Konovalov, V. I. Kostetsky, I. V. Kudryavtsev, V. D. Kuznetsov, I. A. Oding, D. D. Latpev, V. N. Poduraev, A. I. Prompov, Yu. G. Proskuryakov, E. V. Ryzhov, E. A. Satel, V. M. Smelyansky, V. M. Sorokin, L. A. Hvorostukhin, N. F. Khlebalin, L. M. Shkolnik, Yu. G. Shneider, D. L. Yudin , P. .I. Lizarditsin and others.

The main task that arises in the RPM is to find such design, technological solutions and processing conditions that would ensure a given quality at maximum productivity.

For reliable and durable operation of gears, they are presented with a number of requirements for the accuracy of the main parameters of gearing, normalized by the degree of accuracy in four indicators. In this case, the physicomechanical properties of the working elements of the teeth are assigned enlarged, and are most often achieved by heat treatment of the entire gear wheel.

1. Relevance of the topic

The manufacture of gears is a complex multi-stage process, the most lengthy and time-consuming part of which is tooth processing. However, existing technologies do not make it possible to provide modern, ever-increasing requirements for the operational parameters of gears, especially under the conditions of variable action of operational functions on working elements, namely: relative sliding speeds of working tooth profiles, specific loads in zones of edge contact, contact stresses in zones of interaction work surfaces, etc.

The main direction of improving the quality of gears is aimed at improving the accuracy and quality of the working surfaces of the teeth, while the functional orientation of technological influences to ensure the required properties of specific elements is not taken into account.

Ensuring the required properties of gear elements in accordance with the conditions of their operation is possible through the use of a functionally oriented approach based on the full adaptation of the product during its manufacture to the operating conditions in the machine. The application of this approach allows the manufacture of gear wheels of working elements which have the highest wear resistance and wear uniformity along the height of the tooth throughout the entire life cycle.

2. The purpose of this work

The purpose of this work is to increase the operational properties of gears through the use of a functionally oriented approach in the structure of operations of the technological process.

In accordance with the goal, it is necessary to solve the following problems: to develop a classification of gear elements according to their functional purpose, to develop technological impact schemes based on the principles of functionally-oriented technologies, to offer options for implementing the developed schemes using known technological methods.

Conclusion

The choice of a specific method of finishing and hardening processing of tooth elements should be determined by the operating conditions of a particular gear transmission and its purpose, which makes it possible to adapt the product to the external conditions of its use as much as possible.

Thus, the main ways of improving the operational properties of gears are proposed in the work, aimed at reducing and correcting the unevenness of mechanical wear, deformation and breakage of teeth, as well as damage associated with fatigue chipping from the surface of the teeth. The considered methods should be used in combination and take into account the specific operating conditions of the gear transmission.

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