Experimental studies of stabilization of boring cutter form – building top oscillation

The article deals with application of automatic control of cutting tool oscillations, which permits to control the cross-sectional form of a hole. This parameter can be controlled in mass-produced machine tools only through machine tool geometrical relationship, which is ensured during manufacturing of metal cutting machine tools. The purpose of the proposed control system is to increase technological capabilities of the equipment in order to improve boring accuracy as compared with the accuracy regulated by the standards for this type of equipment. Testing of the proposed technological equipment demonstrated high efficiency of damping in the process of boring in terms of response to mechanical and impact actions. Rational combinations of cutting modes were revealed, which provide the needed accuracy and acceptable productivity in the hole cutting process

Analytical and experimental studies of pneumatic vibration exciter in inertia vibroabrasive machining of parts based on beryllium oxide

In the article the results of studying a vibration exciter for vibration machining of the surface of the parts with a pneumatic vibratory drive, which showed its high efficiency when used in highly explosive and associated with fire risk productions, as well as for various technological processes of inertia machining parts based on beryllium oxide, are presented. As a result of the carried out analytical studies of an installation with a pneumatic vibratory drive, a mathematical model of vibration machining process dynamics was determined.The adequacy of the mathematical model of the compressed air flow effect on the roller in the pneumatic grinding set, as well as the roller mass effect on the oscillation amplitude was proved experimentally.The oscillation amplitude dependencies on pressure and the feeding nozzle diameter, when vibration process technology (vibration grinding, vibration polishing and others) of machining of parts is realized, are presented

Increase of precision of casting blocks by applying acoustical oscillations in gas-impulsive moulding

The present article shows the results of the theoretical and empirical research of the study of the impact made by acoustical oscillations on the working process of a gas-impulsive moulding device with the purpose of increasing the quality of the casting blocks’ seal and decreasing the roughness of the surface of a casting block. It has been shown that acoustical oscillations intensify the working process of the gas-impulsive moulding device. With the increase of frequency and power of oscillations the hardness of a casting block first sharply rises, but then gradually decreases. It has been found out that oscillations may help to adjust the precision of a casting block due to high sensitivity of a gas-impulsive process to the frequency of oscillations. The use of acoustical oscillations broadens technological opportunities of the moulding device

The development and analysis of the machining attachments for the decrement of oscillations of a boring bar in the process of the refinement of high-accuracy apertures

Technological patterns in the formation of deflections in shape and positioning of apertures in the process of boring are established on the basis of theoretical and experimental analysis. The dominant factors that influence the formation of processing errors were brought to light, taking into account the specificity of the application of PNC machines (programmed numeral control) and specific automatic control systems that position the shape-forming point of a cutting tool by means of the decrement of its oscillations in the process of aperture boring. The need for and possibility of the control of the process of shape formation under boring have been shown, which fundamentally allows to increase the refinement accuracy and to decrease errors in positioning and roughness of the processed surfaces

The development and analysis of the machining attachments for the decrement of oscillations of a boring bar in the process of the refinement of high-accuracy apertures

Technological patterns in the formation of deflections in shape and positioning of apertures in the process of boring are established on the basis of theoretical and experimental analysis. The dominant factors that influence the formation of processing errors were brought to light, taking into account the specificity of the application of PNC machines (programmed numeral control) and specific automatic control systems that position the shape-forming point of a cutting tool by means of the decrement of its oscillations in the process of aperture boring. The need for and possibility of the control of the process of shape formation under boring have been shown, which fundamentally allows to increase the refinement accuracy and to decrease errors in positioning and roughness of the processed surfaces

Studying the stress-strain state of a more loaded node of a special device for turn-milling

This article presents the results of studying the stress-strain state of the intermediate shaft part, which is subjected to high dynamic loads during the operation of a special device for turn-milling. The values and the nature of the stress distribution in the body of the intermediate shaft are determined using a special software package ANSYS Workbench. The scheme of forces acting on the intermediate shaft has been revealed. The calculation is based on the method of determining the von Mises yield criterion. It has been established that the maximum value of the voltage and the most critical point occurs at the transition of the steps from the diameter of 25 mm to 30 mm. However, the value of these stresses does not exceed the maximum permissible ones and it can be concluded that the parametric dimensions of the intermediate shaft fully meet the requirements to ensure the quality of the device