The studies of the state of gears production show that there is a problem of ensuring the accuracy and quality of teeth tooling in fi nishing operations. To solve this problem, there has been developed a method of fi nishing the teeth of gears and a design of a special reeling tool for its implementation. A feature of the proposed method is its implementation on universal lathes. This article presents the results of an experimental study of the proposed method of tooling and studying the chip formation process. The research methodology is based on the scientifi c principles of engineering technology, the theory of chip formation, the theory of metal cutting and gear tooling. The metallographic method of research has also been used and the experiment has been planned. The results of experimental studies confi rm the possibility of applying the proposed method for fi nishing side surfaces of the cylindrical gear teeth, at this there has been achieved roughness R a = 1.25 ÷ 0.32 μm. The results of studying chip formation show that the tooling of the "shaver-squeegee" ensures high-quality crushing of chips, it somewhat weakens the structure of the chips and improves the working conditions of the tool and improves the quality of the fi nishing tooling of gear teeth.

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The article presents the results of the study performance of cone crushers and the existing technology restoration of their parts. The main reasons for the failure of cone crushers are the following: failure armor of the cone and the middle part, the protective cap, parts of the upper suspension, dust seal rings, bearing rings, the eccentric of the crusher. The most time-consuming is to restore the details of the eccentric crusher. A new technology restoration worn surfaces of the eccentric part and the results of an experimental study of thermal friction treatment (TFТ) after surfacing are proposed. It is revealed that despite the high level of temperature corresponding to intensive treatment modes it is possible to achieve effective hardening. Implementation of the proposed technology allows: eliminate the undesirable effects of softening due to re-riveting and reduce the oxidized layer; increase productivity relative to mechanical cutting methods in 23 times and tool life of more than 10 times; the use of affordable cheap material steel 45, 50, 60G for the manufacture of tools and perform processing at more intensive modes S =0,2-1mm / Rev; n=2000-3000 rpm. It is established that the TFO of the deposited surface part eccentric, provides wear resistance of the treated surfaces parts in 2….8 times more than the factory processing technology, while the depth of the hardened layer can be 1.5…. 2 mm.

Using the existing engineering methodology of designing bolt joints taking up shear loads of dimension chains with gap elements according to N. N. Streletski and other authors’ methodology give similar results, both for the analysis of single bolt joints accuracy and for that of multi-bolt joints. In this article there is considered the affect of gap elements number on the accuracy of multi-bolt joints. There is established the character of the intrinsic errors distribution functions interaction, particularly, limit displacements occurring when mounting single bolt joints, and errors distribution functions determining the accuracy of multi-bolt joints elements mutual orientation. There are considered theoretical schemes of forming setting errors for basic elements in the plane of formed joints for a more complicated case, when shearing forces cause element displacements not obligatory reaching limit values. An analysis of the revealed theoretical schemes for the formation of displacements of the installed elements in the plane of the formed bolted joints shows that the parameters of the displacement distribution are significantly different from the same parameters obtained when calculating dimensional chains with gap units.

The article discusses the issues of improving the technology of cutting teeth of cylindrical gears using modular precast disk milling cutter in various production conditions for gear milling, reducing the cost of tooling materials and facilitating the manufacture of precast disk mills by changing the design. The essence of this design is that when cutting teeth into gears with an involute profile, radial runout is eliminated to a minimum, since the gear cutting operation is carried out on the machine in which the turning was performed. The proposed new gear processing technology – with an involute profile shape and engineered efficient design of prefabricated disk cutters. The main place in the article is given to the design parameters of gear cutting mills, as well as their advantages and disadvantages. Much attention is paid to the determination of the structural and geometric parameters of cutters with various cutting patterns. The described methods are applicable for the design of tools in small-scale production of gears.