Research And Design On Load Limiter System Of Crawler Crane

Crawler crane is a kind of mobile crane widely used in different industries, and the load limiter device of crawler crane is the kernel equipment of safety monitoring, which to large extent determines the safe operation of crawler crane and with tend of large-size and higher complexity places much stricter requirement on safety and reliability. Load limiter system for intermediate and large tonnage homemade crawler crane, however, is still dependant on import for crawler crane with capacity beyond 200-ton, because homemade load limiter system lacks of theoretical as well as practical support and there exists a big technology gap compared with foreign systems. So the research of load limiter system for large and intermediate tonnage crawler crane is necessary and tends to solve the design obstacle.Base on the load limiter system applied in QUY350 crawler crane of Shandong AOQI Heavy Machinery Co., Ltd and developed under cooperation of Mechanical Engineering of DUT and Shanghai Palfen Mobile Control Co., Ltd, the critical technology of load limiter system for large and intermediate crawler crane is researched and designed.(1) According to the theoretical foundation of crawler crane load limiter system and its operation characteristics, the critical technologies and design method as the research main points were proposed.(2) The fundamental theory of large and intermediate crawler crane load limiter system was researched and designed. And based on system functions and performance requirement, hardware system, including main controller, man-machine interface, sensor and so on, were designed and the components in the system were selected.(3) The detection algorithm of the large-size crawler crane load limiter system as the critical technology was researched. To solve the non-linear problem of load limiter device detection, the conic method for non-linear analysis was proposed and simulated in Matlab.(4) The on-site experiment on QUY350 crawler crane of Shandong AOQI Heavy Machinery Co., Ltd was carried out, and then the modification and optimization were made based on comparison between experiment results and simulation data.(5) The regression analysis of load limiter system's performance table and experiment data was accomplished, and the regression model was also established and analyzed by employing least square method.(6) The research, based on Codesys, designed and debugged the software system, in which the kernel algorithm was programmed and encapsulated and systems such as man-machine interface, CAN bus communication, IO system were developed.In the research of load limiter system of large-size crawler crane, the following work has been finished: to build up debugging platform of hardware system; to propose and simulate the non-linear detection algorithm; to carry out on-site experiment; to establish and analyze regression model of crane performance table and experiment data; to develop the software system and commutation system. In addition to above work, the research fruit were applied initiatively in practical project and provided theoretical and practical basis for future research in large-size crawler crane load limiter system design.