针对常规液压静力压桩机的设计方法存在动力源能量利用率低以及大吨位桩机形成困难等问题，结合压桩实际工况，提出和分析了准恒功率设计方法应用于液压静力压桩机设计中的设计原理、准则和实施途径，并将其与常规的恒流量设计方法进行了比较研究．理论分析和实际应用结果表明，应用该方法研究开发的ＺＹＪ系列液压静力压桩机高效节能效果十分明显，并且较好地解决了高压桩速度和大压桩力之间的矛盾，为高效节能大吨位压桩机的设计提供了理论依据 Aiming at the problems of low energy efficiency of power source and difficult formation of large-tonnage pile driver, the design method of conventional hydrostatic pile driver has some problems. In view of the actual conditions of pile driver, the quasi-constant power design method is proposed and applied to hydrostatic pressure The design principle, guidelines and implementation methods of pile driver design are compared with those of conventional constant flow design methods. The theoretical analysis and practical application show that the ZYJ series hydraulic static pile driver researched and developed by this method is very efficient and energy-saving, and the contradiction between the high-pile speed and the pile pressure is well solved. The design of large tonnage pile driver provides the theoretical basis