Research On The Dynamic Characteristics Of The Portal Crane In The Process Of Lifting Cargo

The jib system of portal crane will get obvious shock effect in the process of lifting, unloading, slewing and luffing cargo. The book called design rules for cranes asks us to use dynamic load coefficient to ensure the crane’s strength and stiffness requirements. Through making a complex dynamic load into a static load, the calculation gets simple. But it can’t fundamentally reflect the essence of things, and it is difficult to solve the vibration problems of jib system. In the calculation, the main reason transforming the dynamic problem into static problem is that the causes and influence factors of dynamic load is complex, and it is difficult to simulate the dynamic load. Aim at above problems, this text treats the portal crane as a research object, using finite element method and mechanical kinetics as theories foundation, utilizing Ansys to research the dynamic characteristics of the portal crane under the circumstance of lifting. Main research of the text is as follows:(1) According to the configuration and working principle of the crane, using the finite element analysis software ANSYS to establish the model of machine, and making the static analysis under the conditions of full loads. Combining the crane metal structure theory to analyze the results.(2) Studying the dynamics characteristics of the crane, making the modal analysis of the model, extracting the first4natural frequencies, vibration mode map and animation, and analyzing the results, and providing some optimization methods for the design of new products in the future from the structural dynamic characteristics.(3) Combined with knowledge of mechanical dynamics, establish the mechanical models of the process of lifting cargo. Analyzing the law of dynamic load and getting the specific function of dynamic load through theoretical calculations. Summarizing the approach of analyzing dynamic load.(4) Making the transient dynamics analysis in the condition of the process of lifting cargo by using Ansys. Accessing to the dynamic response results, including dynamics stress and dynamics displacement and curve of dynamic stress of representative nodes, analyzing the results.