Pressure Feedback Hydraulic Hammer Impact Performance And Structural Analysis

Hydraulic pile hammer was a kind of machine, which was widely used in the pile foundation construction of architecture and dock. Compared to such conventional hammer as drop hammer and diesel pile hammer, it owned some advantages such as lower impact noise, no exhaust gas, less vibration, high transmission efficiency and more flexible to control. At the present, the hydraulic pile hammer of home and abroad all adopt the mode of distance feedback to adjust the piling energy. But the piling energy of the hydraulic pile hammer can't be adjusted independently and steplessly. So, it is important to research the Hydraulic pile hammer produced by central south university and Hunan Changhe Machinery Co., Ltd which can be adjusted the piling energy unlimited.Firstly, on the base of comparing with various domestic and overseas similar hydraulic pile hammer, this paper analyzes the structure and working principle of the hydraulic pile hammer produced by central south university and Hunan Changhe Machinery Co., Ltd. This paper compares its structure and its principle of work with various domestic and overseas similar hydraulic pile hammer, and analyzes detailedly working principle of the impactor.Secondly, on the base of dynamic characteristics of hydraulic and impact system, the paper establishes mathematical model for impacting process with the equations of thermoelasticity and analyzes its simulation. And also studies the influence of the pile cushion parameters to pile hammer on the maximum force transmitted to the pile head. Meanwhile, analyzing how to change initial nitrogen pressure and controlled pressure to achieve piling efficiently. This also provides scientific support of developing hydraulic piling hammer.Lastly, the experiments on the ZCY70 mode hydraulic pile hammer produced by central south university and Hunan Changhe Machinery Co., Ltd show that the results tallied with the simulation research. The new-style impactor of hydraulic pile hammer achieved the anticipative effect and demands prove the correctness of theory research.