Functional tests of proportional pressure reducing valve. Authors pointed to the need for use of proportional hydraulics in the mining machinery. Paper describes a study of a proportional pressure reducing valve in the pump control system of the underground locomotive with hydraulic drive. The results allowed users to eliminate the adverse phenomena during operation of the locomotive.

Conceptual design of the versatile gear pump with replaceable components. A review of operating parameters and characteristics of external gear, internal gear and gerotor pumps has been presented. The analysis of the structure of traditional gear pump bodies has been made. The paper presents a conceptual design of the versatile pump, which enables the interchangeable use of external, internal and gerotor gear assemblies within a standardized body with fixed and replaceable parts.

Tightness research of rotating ferrofluid seals working in the water environment. Ferrofluid seals for rotating shafts belong to the class of non-contact technical seals. The development of solutions to extended possibility of using ferrofluid seals in liquid environment, especially in water can give new opportunities for applications. A purpose of this publication is to determine the impact of water pressure and peripheral speed on the tightness of the seal.

New flow devices. The importance of flow devices in the modern industry has been accented. The paper presents new designs of such solutions and their principles of operation, as well as their functions and operational advantages. It has been pointed to the need for more widespread use of a flow mixer primarily in the chemical and food industries, as well as the use of a water curtain in the mining industry.

Flat sealing performance testing during cyclic temperature changes. The test stand and the test procedure for static seals operating under variable heat load. It has been emphasized that the test procedure applies to heating and cooling cycles of seal. The tests have been conducted for all kinds of flat seals and a change of their thickness, the leakage and stress changes during each thermal cycle have been checked.