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Cryogenic pumps are of particular importance in mobile machinery, in particular in wheeled and tracked vehicles. This is due to the development of hydrogen energy. In the nearest future, we will see hydrogen powered mobile cars. In this regard, it would be useful to have an up-to-date overview of modern cryogenic pumps. This article discusses the main types of cryogenic pumps, identifies problems encountered in the design and operation of pumping units and formulates the requirements for these devices. A brief overview of the most common designs of cryogenic pumps of foreign and Russian production is presented.

Mobile vehicles, both tracked and wheeled, are often used to refuel/unload stationary tanks. In this case, the unsteady mode of operation of such centrifugal pumps is often observed. A constant change of operation conditions, in particular the static component of the pump head, leads to a change in its operating mode, as a result of which most of the time the pump operates in off-design mode. A methodology has been developed for determining the actual pump efficiency for a tank filling-draining cycle with two variable parameters: the distance from the level of the pumped fluid in the well to the bottom of the tank (to the on float) and the tank height (or the distance between on and off floats).

The article presents the experience of operating real pumping stations in urban water supply. The basic principles of practical modeling of the operation of a group of pumps for a common load are considered. The main errors in the modernization of pumping equipment of water supply units are analyzed.

This article is devoted to the study of cavitation characteristics of a centrifugal cryogenic pump. Hydrodynamic simulation of the fluid flow in the wet part of the pump was carried out in order to determine the output parameters of the pump. A critical increase in the temperature of liquid helium, corresponding to the beginning of cavitation in the pump, was determined. A cavitation performance of the pump was built under given operating conditions and a critical NPSH was determined.

This article discusses a way to solve the problem of operational quality control of concrete in the construction of critical structures with the use of small-sized testing machines. To reduce the testing machines size, it is proposed to use a high-pressure hydraulic drive. As a promising way to control the machine, the practical experience is described of using a pump with a constant displacement, the drive of which uses an electronic frequency converter.