Despite of the increased share of oil wells equipped with submersible electrical centrifugal pumps, a considerable part of them is equipped and operated with sucker-rod pumping units. When operating wells with sucker-rod pumping units, different plunger pumps are used. The rod string is operated in severe environment due to long contact with highly corrosive well products and time-variant loads. Taking into account all acting loads, the diagnostics of the condition of sucker-rod pumping units is a difficult task. At the majority of oil fields in Russia, the operation of wells equipped with sucker-rod pumping units is controlled by portable and stationary dynamographs of various models. Moreover, dynamographs are used, as a rule, only to obtain images of dependence of the force on the polished piston rod upon its stroke. Based on dynamograms it is possible to find the well flow rate, pump capacity, force on the polished piston rod, etc. But one of the main problems to be solved with the help of dynamometry is the forecasting of down-hole equipment condition in the process of further operation. In this paper we overview the methods to diagnose the condition of sucker-rod pumping units based on dynamograms. The aim of the work is to develop the mathematical model to forecast the failures of down-hole pumping equipment on the results of dynamometry to automatize the control process of the unit operation. The research tasks are to analyze the existing methods for diagnosing the condition of sucker-rod pumping units, and to develop the mathematical model for forecasting the failure of the valve unit leakage. As a result, the method for forecasting the increased failure on the example of the fluid leakage in the pump injection unit is proposed. The permissible boundaries of the change in the relative force on the polished piston rod are drawn up. As a result, the failure increase is forecasted based on the frequency of the relative force on the polished piston rod getting within the interval obtained.

Своевременное диагностирование и прогнозирование отказов в работе глубинного насосного оборудования позволяет увеличить межремонтный период работы скважины. Наиболее распространенным и эффективным способом диагностирования глубинного насосного оборудования является анализ результатов динамометрирования, большинство из которых основаны на визуальном сравнении образцов практических динамограмм с эталонными.В данной работе предложена методика диагностирования состояния глубинного насосного оборудования при помощи интервальных оценок результатов динамометрирования на примере утечки жидкости в нагнетательном узле насоса. Для определения границ данного интервала использовано распределение Стьюдента. Из анализа построенного доверительного интервала при ходе полированного штока вверх установлено, что он сужается на промежутке от 0,3 до 0,7 м. Данный диапазон соответствует интервалу, на котором при безотказном состоянии глубинного насосного оборудования шток воспринимает максимальную нагрузку, что свидетельствует о начале движения плунжера насоса вверх.На основе разработанной методики диагностирования предложена методика прогнозирования отказов на примере утечки жидкости в нагнетательном узле насоса. Построен интервал изменения кривой зависимости относительного усилия на полированном штоке от его хода. По частоте вхождения данной кривой в полученный интервал с надежностью 95 % строится прогноз о нарастании отказа, связанного с негерметичностью клапанного узла.

The purpose of this study is to develop a circuit for an automobile air conditioner, which will reduce the consumption of power developed by the engine. This paper proposes the design of an automobile absorption air conditioner. A description of the principle of operation of an automobile absorption air conditioner operating on a cycle of a one-stage absorption refrigeration machine has been given in the paper. It consists of a stripper (generator), a condenser, an absorber, an evaporator. Lithium bromide (LiBr) solution has been used as an absorbent, which has a low boiling point, is non-toxic and safe. 3D-models of the absorber and generator of an automobile absorption air conditioner has been developed in the course of the research. The absorber is designed to form a weak absorbent solution. This solution is supplied to the generator heat exchanger using a liquid pump. There it is heated by the exhaust gases to the boiling point. The solution evaporates and water vapor enters the condenser (evaporator). In the generator, the solution is concentrated from 52 to 60 %. After that, water vapor is supplied to the absorber from the condenser, and a concentrated absorbent solution is supplied from the generator. It should be noted that the generator is a key element of an automobile absorption air conditioning system. Inside it is a strong LiBr solution that feeds the absorber. The design of the air conditioning system does not provide for the use of a compressor and allows to reduce the power loss of the power plant to the drive of the liquid pump. According to calculations, the pump drive power was 0.17 kW. For comparison, the compressor of a modern car air conditioner consumes 7–11 kW. An absorption car air conditioner provides the following advantages: additional engine cooling, environmental friendliness, fuel economy, efficient use of the heat of vehicle exhaust gases. A distinctive feature of this design is that it is proposed to use the heat of the exhaust gases for the process of heating the absorbent. This design can fully compete with the existing modern car air conditioners.

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