Analysis on Virtual Assembly Tolerance for Pitch-adjustable Lateral Propulsion Device

Lateral propulsion unit is the propeller mounted on the side of the ship, the lateral force in the rotary side generated by the propulsion device can reduce the ship's turning radius, so the yaw of low voyages will not happen. By adjusting the pitch angle of the propeller, the adjustable pitch for lateral propulsion device can change the size and direction of the lateral thrust. The device assembly technology has great significance in improving assembly quality, shortening cycle and reducing the cost of production assembly. This paper attempts to use the secondary development tools of UG, and the Vis-VSA software to design an adjustable pitch propeller assembly tolerance analysis system for tolerance problems in the assembly of thruster. On the one hand, there are studies on the information extraction algorithms of the thruster assembly model in UG, and management of the extracted assembly feature information in SQL Server2008.On the other hand, there are some researches about the method of generating assembly dimension chains based on the assemble information database. Based on the study aforementioned, the tolerance analysis of Monte Carlo method for the assembly dimension chain is fully illustrate. Finally, the optimal tolerance design is obtained by calling Vis-VSA module to analyse assembly tolerance.