The relevance of the research is due to the need to modernization of the risk man-agement process of agricultural enterprises and their associations. In this regard, this article is aimed to develop areas for implementation of risk-oriented manage-ment of united agricultural enterprises in order carrying out a comprehensive diag-nosis of economic risks in the economic system of entities and timely identifica-tion of threats to sustainable economic development under uncertainty of macro-, and microenvironment. The study based on methods of analysis and synthesis. As well as modeling method and statistical methods applies in article. The article pre-sents the results of the development situational matrix of risk-oriented manage-ment of the economic system according to the probability of decision-making op-tions in economic activity was proposed. In the course of the research, were con-sidered the risk-oriented management in the economic system of united agricultur-al enterprises for sustainable development. In adittion, model of qualitative and quantitative analysis of economic risks in the economic system of the united en-terprises of agricultural production is presented. The practical significance is based on finding the forecast risk factors of change of effective indicators of economic activity in the economic system of the united enterprises of agricultural production and developing the priority administrative initiatives on minimization of economic risks.

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The article is devoted to the research of the influence of geometrical parameters of the inlet section of the multistage pump radial channel guide device on its hydraulic efficiency. The obtained values of hydraulic efficiency, considered depending on the geometrical parameters of the guide device, are given. The efficiency parameters were obtained via hydrodynamic modeling. Recommendations on the optimal geometric parameters are offered and compared with already known semi-empirical formulas.

The object of study is a single-stage double-suction axially split volute casing centrifugal pump. Background. In the design process of pumps, the problems associated with ensuring the tightness of the axial joint of a pump casing being under the effect of mechanical and temperature loads, are being solved. During the study of axial joint tightness, numerical calculation methods are used to estimate the pressure intensity on the contacting surfaces. A detachable joint under the external load satisfies the criterions of the tightness if the pressure intensity on the sealing surfaces is higher than values of the specific pressure prescribed by regulations. However, inability to experimentally determine the pressure intensity on the contacting surfaces has so far prevented to assess the accuracy of results obtained by the numerical calculation methods. Objective. In order to verify the numerical results obtained by mathematical models, an experiment was carried out using a special Prescale film that registers the magnitude of the contact pressure on the joint of the specimen model of the flange fragment. Based on the experimental results, an analysis of the pressure intensity distribution was conducted. Methods. To conduct the experiment, there was developed a method for determining the pressure intensity on the contacting surfaces according to the proposed scheme of the specimen of the flange fragment. Results. A comparative analysis of the solving results obtained for the contact problem on the finite-element models of the flange fragment and the zone of the pump casing joint in the discharge chamber area showed a good coincidence of the results. Analysis of results obtained experimentally on the specimen of flange fragment and results of the numerical calculation on the flange fragment model also showed a good agreement. Conclusions. Therefore, results of the calculation of the pressure intensity in the detachable joints on mathematical models have been experimentally confirmed.

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