The Hydraulic Piling Hammer Piling Instability Reason And Solution Studies

Relative to conventional pile hammering equipments, hydraulic piling hammer has a lot of advantages, such as lower noise, less vibration, no exhaust gas and high piling energy. The nitrogen explosion type hydraulic piling hammer gets increasing more attentions, just because it can release more beating energy without increasing the lift height. According to the instability of the lifting height and of the beating frequency in debugging, the reasons were studied by theory analyzing and model simulating, and the corresponding optimizations were made, correctness of the former works was confirmed by the experiment finally.Firstly, the spatial structure as well as the hydraulic principle of the nitrogen explosion type hydraulic piling hammer was elaborated briefly, and the principals of the stroke controlling system and of the oil supplying & returning system were also analyzed, which lay the foundations for the subsequent modeling and simulating. Secondly, MATLAB/Simulink/Simscape was taken use of in modeling the two key parts of the stroke Controlling system and the oil supplying & returning system, the models of other parts, including the piling hammer system, as well as the pile-earth system were set up, too. From the simulating of the model, the reasons lead to the instabilities of the lifting height and of the beating frequency were analyzed further more. From the studies on the incipient position of the stroke valve as well as the gain area of the main controlling valve, the parameter ranges which can avoid the wrong actions of the main controlling valve were got. And the important effect of the check throttle to the improvement of the beating stability was found from the study on the controlling project of the charging and discharging of the high pressure accumulator. The best parameters combination of the high accumulator charging and discharging controlling system was got from the Genetic Algorithm on combinations of the key parameters. The performances of the system with other combinations beside the best one were also studied to test the correction of the optimization. Finally, the correctness of the former modeling, simulating and optimizing was confirmed by the experiment.