Flange connections of chemical technology equipment and pipelines

The subject of the research is the most common type of detachable joints in chemical, petrochemical, oil refining, food and energy machine and apparatus construction, namely flanged joints of technological and auxiliary equipment, as well as pipelines. The study of the state of the issue and trends in the development of structural and technological design of flanged joints is based on a critical analysis of scientific and technical sources of information and, above all, patent information of the leading countries of the world, since it is in the patent documentation that information is given about innovative developments in the relevant field of engineering and technology. With the help of methods of analysis and synthesis, flange connections that affect the efficiency of operation of equipment and pipelines in the chemical and related fields of technology have been systematized. A thorough classification has been developed for each type of device, based on which the most interesting designs proposed by scientists, designers and inventors of the world's leading countries have been examined in detail. A critical assessment of most of the above constructions is provided, their advantages and disadvantages are discussed. Preference is given to sources of information from the end of the second and beginning of the third millennium. The constructions of flanged joints were analyzed depending on the degree of assembly, the degree of mobility of their structural elements, the possibility of removing the flanges without dismantling the entire joint, the mechanism of compression of the sealing gasket, the presence of additional functions, as well as the material of the flanges. It is shown that, despite the considerable variety of developed designs of flanged connections, the most demanded by the industry are flat welded and butt-welded flanges, as well as free flanges on a welded ring. However, thanks to the advances in materials science and computer modelling, the search for new flange connection designs continues. The developed detailed classification of flange connections can be useful to the developers of new equipment for the creation of highly efficient technological equipment of various industries.