Pipeline fittings, which include butterfly valves, are not unimportant in pipeline systems. The main function of this design element is to prevent emergencies in pipeline systems. The principle of operation is based on closing of the shut-off device in case of change of direction of the transported medium flow. This ensures reliable flow control and prevents backflow of the medium in the pipeline. The rotary check valve provides reliability, tightness and safe operation of systems, as well as durability with regard to safety requirements. The article deals with the design and calculation of rotary check gates. The purpose of development of such a model range is to create a durable and reliable design, which will be able to ensure during the whole service life a safe operation in production with different parameters of the working environment. To confirm the reliability and serviceability parameters of the design, strength calculation of the butterfly valves has been carried out. As a result of numerical modelling of all designed check gates, the calculated parameters allow to give positive assessment to the gates and confirm compliance with technical requirements.

Keywords: rotary check gate, modelling, mathematical modelling, finite element method, calculation of reliability indices

The service life of shut-off valves operated at sites of hazardous production facilities with ultra-high parameters of the working environment is largely limited by the wear resistance of contact surfaces. In this regard, to increase the durability of contact surfaces, technological methods are used to modify the surface and special functional coatings are used. The development and selection of new functional coatings are inextricably linked with their comparative study based on the determination of the most significant characteristics through testing. The purpose of this work is an analytical review of the most common test methods for evaluating the characteristics of multicomponent nanocomposite coatings applied to the contact surfaces of valves to increase their wear resistance. Based on the results of the analytical review, recommendations are given for testing multicomponent nanocomposite coatings.

Keywords: pipeline fittings, functional coatings, test methods, service life, wear, friction, hardness, corrosion, tribology

Pipe fittings, which are one of the main elements of any type of pipeline networks, can be used for various purposes: shut-off, reverse, safety, control, separating, shutting off, etc. In order to control the performance of this element, it is necessary to carry out various tests in the prescribed manner, the main ones being pneumatic. This study is devoted to the development of equipment for in-plant pneumatic testing of rotary check valves for pipeline systems of hazardous production facilities with ultra-high parameters of the working environment. For this design of the installation, the simulation of the stress-strain state of the elements of the installation was carried out, as well as the gas-dynamic calculation of the test circuit of the installation.

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