This page has set up a mechanics model and a optimized mathematics model of the working process for the YH-300A Pipe Hammer Using compound model method. Regarding the impaction energy as object number, we can make an optimizing design to the structure. This page also makes a calculation of impaction energy and impaction frequency of the original structure. After the optimize calculation, comparing to the original design the impaction energy has improve at least 19% and the impaction frequency has improve a little. At the same time, we make the finite element calculation to the piston of the YH-300A Pipe Hammer. After the finite element calculation, both the original design and the optimized design have proved the biggest stress located in the vent. And the stress on the impaction side is great. So we should use the finite element method to collate the intension of the body as we use the shock wave method to collate the intention. It can improve the shortage of the using of shock wave method in the intention calculation.