The article discusses the production and use of environmentally friendly fuel - pellets. A review of the designs of mobile pellet production plants was carried out, the advantages and disadvantages of these designs were identified. Potential consumers of pellets and equipment (heating boilers for which pellets are the fuel) are considered. A mobile complex for the production of pellets on the chassis of the MSN-10-004-03 . The technology of pellet production using a mobile mobile installation is described.

Keywords: pellets, mobile plant, design, biofuels, production technology

Pipeline networks today are the main and one of the safest ways to transport all kinds of media. This engineering system consists of various elements, one of which is pipeline fittings that regulate the parameters of working media and protect pipelines from overpressure. In order to control the operability of pipeline fittings, it must be subjected to comprehensive tests, one of which is a leak test. The presented study describes the developed design of a technological hydraulic installation intended for use as part of process equipment for conducting in-plant testing of pipeline valves. The results of modeling the stress-strain states of the main units, as well as the hydraulic calculation of the test circuit of the installation are presented.

Keywords: rotary check valve, pipeline fittings, pipeline system, mathematical modeling, finite element method, strength analysis, stress-strain state, computational fluid dynamics, hydraulic tests, technological hydraulic installation