Design Of The Supporting System In The High Altitude Fire Truck

Currently, the emergence of the large number of high-rise buildings has brought about great challenges to the fire trucks and equipment performance. Aerial fire trucks are the major fire-fighting and rescue equipment for high-rise buildings, including Aerial Water Tower fire engine, Aerial Ladder fire engine and High Altitude Fire Truck. The performance of High Altitude Fire Truck is better than the other two types within the rated operating range of20-30m. The structural stability of High Altitude Fire Truck is the key factor affecting its safety and smooth operation, and the structural stability is ensured by the supporting system consist of landing leg and subframe. The25m High Altitude Fire Truck is taken for example to research and design its supporting system in this thesis and the work is carried out from the following aspects:(1) The structure design of supporting system in High Altitude Fire Truck is completed. Firstly the required chassis is selected, next the subframe parameter of the selected chassis, the types of landing and the standing legs are designed, finally the landing legs span is calculated and cylinders are selected.(2) The structural stability analysis and optimization of supporting system in High Altitude Fire Truck is completed. Firstly the Solid Works software is taken to build the mechanical structure3D model of the designed supporting system. According to calculation of the landing legs pressure, the most dangerous condition is obtained next. Then the ANSYS software is used to analyze the structural stability, this way the designing reasonableness is verified.(3) The leveling strategy of supporting system in High Altitude Fire Truck is completed. Firstly the leveling method is designed, and the leveling thread is ascertained. Next the leveling principle is discussed and according to the principle the mathematical model is established. The "Moving to the center" leveling method is selected to complete the leveling strategy design. Finally the leveling strategy is ascertained to be automated closed-loop leveling system.(4) The leveling controlling system design of supporting system in High Altitude Fire Truck is completed. Firstly the hydraulic control system is designed, next the electro-hydraulic servo and proportional valve is selected, and hydraulic control schematic diagram is designed. Then the hardware of controlling system is designed, according to the hardware components, the core components controller and sensor are selected. Then the controlling system software is designed, Siemens PLC is selected to be the main-controller. The controlling procedure is ascertained, and the controlling program is designed according to the controlling procedure. Finally the configuration software is used to debug the designed controlling program in order to verify the designing reasonableness.This research will provide basic theoretic support for developing the supporting system for Aerial fire engine and contribute to optimize the production design, shorten the enterprise development cycle, improve the production quality and reduce the production costs. At the same time, it can solve the facing problems of enterprise and provide a good reference to the study of relational productions.