The State Monitoring Of 40t-43m Crane's Mental Structure

As a project of apply and research on equipments monitor technology in portal handling machine, the paper has goodly a guidance meaning to promote the level of management of portal equipments. It's also beneficial to the reform of facility maintaining system, and which makes it more conform to the policy of our country's mechanism management.Portal crane is primary handling device in portal work. The consequence caused by crane's metal structure to lose efficacy is very serious. But it's regretted that the question have hardly focus enough attention. That includes many questions about theory and applying. So the writer probed into the theory and the method of monitoring cranes' station that can apply in practice base on rupture mechanics, elastic mechanics, and science of computer. Those methods is worthy popularizing in the digesting, controlling, maintaining of metal structure of port mechanism with the guide of basic theories. Those have been confirmed by the practice I discussed in this essay. The main contents include:1. According to my research about the damage of cranes' metal structure of our country's ports recently and the investment of the causes and principles, we pointed out the necessity and importance of the inspecting of the state of cranes' mental structure.2. Through fatigue test and theoretic analysis of structure, principle of destruction is educed about crack due to structure fatigue to mental structure of portal crane. The critical crack and stress put forward provides theoretic foundation for monitoring portal machine.3. Applying steady theory of board, studying the problem of earlycurvature, flexibility model, welding remaining stress, elastictransmutation and brace condition and so on, conclude that structure of beam is primary place where metal structure of portal crane lose stabilization and the break of main beam is result of losing partial stabilization of main board.4. Study the influence of welding on structural support. Because of effect of welding remaining stress on static strength, fatigue strength and structural stabilization of metal structure, the stress due to load is a result of heap of remaining stress. Thin board will have flexure transmutation in part and drop out load when the stress of thin board goes up to the steady critical value, resulting in losing stabilization wholly.5.It is the first time to construct a set of monitoring system of cranes mainly on the flexibility and vibration in our country. It has important meaning to improve the modern management of port equipments' inspecting.