Based on the analysis of the developed mathematical model, this paper proposes optimal operating modes of the vibroimpact device to ensure the intensification of driving construction piles. It is an original design of a modern, highly efficient device for driving construction piles, equipped with a compact, powerful hydraulic impulse drive unit. To develop a mathematical model of the construction pile driving technology, the following methods were used: mechanoreological phenomenology, hydrodynamics, and generalised laws of mechanics. Mathematical models of the dynamics of technological processes of driving construction piles with a vibroimpact device are improved based on a hydraulic impulse drive unit in the form of a spatial non-stationary formulation of the problem and integral equations of dynamic characteristics of the moving elements of the drive unit. The study obtained the distribution of the pressure and velocity of the working fluid in the hydraulic unit of the vibroimpact device, as well as changes in the kinematic parameters of the elements of the technological equipment based on the mathematical model developed by the finite volume method, using numerical modelling and high-performance computer systems. Optimal modes of operation of a hydraulic impulse drive of a vibroimpact device are proposed to provide an intensification of the construction pile driving technology. It was found that when low-frequency vibration is applied, the driving of construction piles is intensified. Application of a hydraulic impulse drive that is based on two-stage vibration excitation allowed implementing the vibroimpact modes of the device. The average pile driving speed with a vibroimpact interaction is five times higher compared to conventional driving methods

In this work, vibrations were investigated during loading and unloading operations of mobile agricultural machines, which are considered to be one of the most labor-intensive components of the transport process. Therefore, idle machines during carrying out operations and in anticipation of them remain quite significant, which is due to the insufficient level of mechanization of loading and unloading of cargoes on transport, with a fuzzy coordination of actions of different organizations in the overloading of loads at transport nodes and for some other reasons. The main means of mechanization are stationary and gantry cranes for containers, heavy loads and large packages, as well as means of mechanization on the railway or on the chassis of a standard mobile car or special chassis. In our opinion, the use of hydraulic impulse actuators in the production of vibration and vibration shock unloading devices is promising, due to the simplicity of construction, compactness, high energy intensity, a wide range of regulation of operating parameters and the ability to work in automated mode. In particular, a promising area is the creation of removable attachments with hydro-impulse drive for dump trucks, onboard vehicles, tractor trailers and other vehicles. For intensification of processes of unloading of a body of a trailer-dump truck of tractors the hydraulic vibrating shock device is developed. It accelerates the unloading and cleaning of the body of agricultural products. Reduced costs and reduced oversized idle tractors with unloading trailers. Therefore, the development of vibration and vibration impact equipment for use in loading and unloading operations on mobile agricultural machines and in general on transport is an urgent task.

DEVELOPMENT OF THE EVALUATION MODEL OF TECHNOLOGICAL PARAMETERS OF SHAPING WORKPIECES FROM POWDER MATERIALS R . I s k o v y c h -L o t o t s k y

The working process and regularities of the functioning of vibrating and vibro-impact machines based on hydroimpulse drive with a singlestage valve pulser are analyzed. The essential characteristics determining the conditions for the excitation and existence of periodic oscillations of the valve-pulser shut-off valve are determined. Using the criterion of A. Hurwitz, based on the differential equation of motion, the existence of undamped periodic oscillations of the valve-pulser shut-off valve is analytically justified.Streszczenie. Przeanalizowano działanie i regularność pracy maszyn wibracyjnych oraz maszyn poddawanych wibracjom opartych na napędzie hydro-impulsowym z jednostopniowym zaworem impulsowym. Określono podstawowe cechy wpływające na warunki wzbudzenia oraz występowania drgań okresowych zaworu impulsowego. Przy zastosowaniu kryterium A. Hurwitza, opartego na równaniu różniczkowym ruchu, istnienie nietłumionych drgań okresowych zaworu impulsowego jest analitycznie uzasadnione. (Warunki stabilności zaworu sterującego hydraulicznym napędem impulsowym maszyn wibracyjnych oraz maszyn poddawanych wibracjom).

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