Five-axis NC Machining Parameter Optimization And Energy Calculation Of Propeller

Marine propeller is an important component of marine power systems. The design and manufacture of marine propeller play an important role for improving the performance of the ship propulsion systems. Propeller blade is a typical part of free surface, which has large diameter and complex shape. The region between adjacent blades is narrow and prone to collides with tools. The production cycle of propeller is long, optimization of cutting parameters is an important issue that affects the efficiency of NC machining, and plays the important roles for improving product quality and productivity. In this thesis, the machining process planning, tool path generation, cutting parameters optimization, energy calculation and other issues of processing propeller with 7-5 axis lathe & mill machine tools have been studied.The formation of the propeller blades and geometric characteristics is analyzed in this thesis. The formula that transforms the data points from the local coordinate system into the global coordinate system is obtained and the coordinates of data points in the global coordinate system are calculated. Surface profile is obtained by fitting data points. Then leaf surface model is built.The propeller machining process is analyzed according to geometric characteristics. The leaf surface area is divided into overlapping and non-overlapping areas. Considering the requirement of propeller, the tool diameter and it's reasonable angle used in the processing are calculated. And the step forward, stepover and scallop are also calculated. Then generation method of cut location point in side milling is given. Finally the interference-free tool path is gained. For the purpose of improve processing efficiency and quality, the force of NC machining is analyzed by Production Module. The cutting parameters are optimized, and then the processing code is generated.The energy calculation method of processing propeller with 7-5 axis lathe & mill machine tools is analyzed. The energy in processing is calculated and examples are given. The results show that machining in machine tool can reduce energy consumption by about 20% than wheel grinding by hand.