Некоторые особенности разрушения лопастей гребных винтов из нержавеющей стали для морских судов

Abstract

The problematic issues of the operation of propeller blades made of stainless steel, using the example of the analysis of repairs and destruction of the propeller blade of the CPP nuclear container ship Sevmorput are discussed. The greatest danger to the operation of the vessel is the exhaustion of its load-bearing capacity by the blade at loads less than the maximum due to the appearance of surface and internal defects in the blades, further growth over time, due to improperly carried out repair work. To check the strength, calculations of the propeller in the nozzle were made at an average speed of 14.5 knots at a rotation speed of 100 rpm in the SolidWorks software package. By 3D modeling of the propeller, with the rotation of the blades at various angles, a picture of the distribution of pressures on the suction and discharge surfaces of the blades was obtained. Strength assessment showed that the processes that led to the blade breakage are based on the concentration of stresses caused by the presence of hidden defects. An analysis of the physical, mechanical and metallographic properties of the blade material with weld metal (used to correct casting defects and during repairs in operation) was carried out on samples made from a fragment of the root part of the damaged blade left after the break. The results of the study of micro-sections of the blade material made it possible to build an adequate physical model of fracture and formulate recommendations regarding the operation of stainless steel propellers of marine vessels.