Study of efficiency of application of locally reinforced fitting units with stiffening ribs

Abstract

In this work, one of the main methods of strengthening the hole in the apparatus is considered - strengthening with overhead rings, the advantages and disadvantages of using reinforcing rings are indicated. An analysis of the main methods of strengthening the openings of pressure vessels and devices shows that the difficulties in designing and installing the reinforcing rings are in the technology of assembly, detection of weld defects and detection of the local location of this defect. The work shows the possibilities of using locally rib-reinforced nozzle assemblies, which in some cases can serve as an alternative to reinforcing rings, and are also more technological in manufacture, repair and control. Calculations show that the use of two stiffening ribs oriented along the generatrix of the shell to strengthen the hole allows reducing stresses in the area of welding of the nozzle to the body of the apparatus under static load. Practical experiments carried out at the same time showed that in conditions of dynamic loading, it is categorically not recommended to use the strengthening of the nozzle with local stiffening ribs oriented along the generatrix of the shell.

Welding Technology for Liquefied Natural Gas Tanks

“…Optimum parameters of 9% nickel steel are achieved by very precise temperature control during production and controlled quenching. Preheating is performed only if high humidity is condensed on parts or welding works are carried out at temperature below 5 ° C [1,[16][17][18][19].…”