ANALYSIS OF MODERN METHODS OF REPAIR, GRINDING AND BALANCING OF THE PROPELLER FOR LARGE-TONNAGE SHIPS

The methods for repair, grinding and balancing of the propeller are analyzed by the author. The article deals with the control issues that prevent and detect defects in the screw-propeller blade, as well as to improve the performance of a large-tonnage vessel after processing the propeller surface. The purpose of this article is to consider the main technological solutions and methods of repair and renewment of ship propellers from the perspective of recent foreign attainments aimed at introducing these methods to the domestic practice of ship repair. The state of technological processes and prospects for determining the appropriateness and directions of mechanization or automation of ship repair production is evaluated. The article also proposes the means of mechanization and automation in operations reducing the time for repair of the propeller, including: fitter, molding, foundry and welding. In the process of mechanization (automation) in order to reduce manual labor, it is proposed to use the following means of technological equipment: the installation of induction heating for heat treatment of the propeller and welds, Uint-100-2,4; the milling machine RVD-90A is a unique machine with numerical control. Various devices are used to reduce power losses due to a special guiding apparatus for improving the efficiency of propellers (a contra-propeller fairing, a nozzle guide, a pear-shaped thickening on a rudder blade, a tunnel feed on ships with a small landing, etc.). The purpose of mechanization and automation of technological processes is the comprehensive reduction of manual labor, acceleration of productivity growth, improvement of working conditions and its safety. All this ultimately leads to an increase in the efficiency of production and the improvement of product quality.