The assessment of stressed-deformed state of tube bundle of the heat-exchange apparatus with the fixed pipe grids

Abstract

Ensuring reliable operation of heat exchange equipment is the key to continuous and efficient operation of the entire technological unit or assembly as a whole. During installation, repair or operation, various deviations of the construction elements of the heat exchangers from the values specified by the project are possible. One of the possible scenarios of such deviations is the deviation of the transverse baffles of the tube bundle from the vertical design position during installation. Since the transverse baffles in the tube bundle play the role of supporting constructions, when they deviate from the vertical design position and at the same time are exposed to operational loads, it is possible to form zones of concentration of increased stresses in the heat transfer pipes, and then the occurrence of defects in these zones. Currently, the work on modeling heat-exchange equipment using specialized software systems for assessing the stress-deformed state taking into account the influencing factors and identifying the most unfavorable zones with maximum effective stresses is relevant. This paper investigates the interconnection between the magnitude and direction of deviation of the transverse baffles from the vertical design position on the stress-deformed state of the tube bundle of the heat exchanger with fixed tube grids along the rows of heat transfer tubes.

Influence of Dry Friction on the Dynamics of Cantilevered Pipes Conveying Fluid

“…Paidoussis et al [8][9][10] reviewed the dynamical behavior of pipes conveying fluid under different boundary conditions and pointed out that a cantilevered pipe would be subjected to flutter instability when the internal flow velocity becomes sufficiently high. For heat-exchange bundle structures existing in the nuclear industry, beyond the onset of flutter instability, the pipe would be subjected to periodic motion and might contact the surrounding supporting plates or pipes [11][12][13]. In this case, the effect of contact and possible dry friction between the pipe and the surrounding structures may be pronounced.…”

Investigation of stress-strain state of pipeline hoist taking into account installation displacements

“…Even small displacements can have a decisive effect on the stress-strain state (SDS) of the piping. When acceptance of installation works with the presence of installation deviations of equipment, the SDS assessment of its piping is usually not carried out [4][5][6].…”