Design Of Automatic Measurement Equipment For Large-scale Marine Propeller Blades And Optimization Of Key Components

As one of the key components of the ship,the quality of marine propeller will directly affect the propulsion efficiency and service life of the ship.With the development of China’s shipbuilding industry in the direction of large-scale,high-speed and automation,the accuracy requirements for large-scale marine propellers are getting higher and higher.Marine propeller blades need to be inspected before the blade roughing,semi-finishing and finishing operation.The results provide reference data for the determination of the subsequent operation’s machining allowance and eligibility.The traditional manual method of measuring propellers can no longer meet the requirements of modern manufacturing companies for high measuring accuracy,efficiency and large application scope.Based on the company’s on-site investigations,the study on the measurement technology of propeller blades was conducted.A large-scale marine propeller blade measurement equipment was designed.The specific content included the following aspects:(1)Based on the difficulty of propeller measurement and the needs of the enterprise,the parametric design method was used to complete the overall design of the propeller blade measurement equipment by UG three-dimensional software.The measurement machine automation scheme,the gantry propeller measurement equipment scheme and the vertical propeller were proposed.Comparing each measuring equipment scheme’s advantages and disadvantages and considering the influencing factors such as the size and accuracy of the measuring propeller,the vertical propeller blade measuring equipment was finally determined.(2)Large marine propellers are large in volume and heavy in mass.It usually takes a long time for manual positioning and clamping.A new method for rapid positioning and clamping of propeller was proposed,mainly including guiding device,centering detection device and pushing device.The blade surface measurement device and the blade back measurement device were designed to achieve simultaneous measurement of the upper and lower surfaces of the propeller blade.Selection of standard parts and mechanical design calculation of key parts were finished.(3)Combining the theory of finite element analysis and the actual operating conditions of the propeller testing,ABAQUS software was used to perform static analysis on the key components of the propeller blade measurement equipment to obtain the displacement and stress cloud diagrams of the components;Modal analysis on the main structure of the measurement equipment was performed to obtain low-order natural frequencies.According to the static and dynamic analysis results,identify weak parts were identified to provide reference for subsequent optimization.(4)The multi-disciplinary optimization software ISIGHT was used to integrate UG and ABAQUS to build a cantilever beam optimization simulation platform to realize automatic control of simulation data.The optimized simulation platform was used to complete the experimental design,establish the approximate model.The goal is to parameterize size optimization of the cantilever beam with the lowest quality and the best mechanical performance.The optimization algorithm was completed.The results showed that the mass can be reduced by 44.69%,and the deformation can be reduced by 21.78%.The light weight of the cantilever beam is better realized,and the influence of the cantilever beam deflection on the measurement accuracy is reduced,and the accuracy of the entire measurement equipment is improved.