Study of mechanism of underwater hydraulic impulsion tool

To finish surface clearance of an underwater petroleum pipeline, a scheme is presented for designing an underwater hydraulic impulsion tool.This impulsion tool uses a high speed on-off valve to control to-and-fro motion of the distributing oil valve core, which impels the cylinder rod to-and-fro motion to form impulsion.According to the scheme, the sealed structure of the head tool and the volume of the nitrogen room were analyzed further.The sealed structure of the head tool was designed and analyzed, and feasibility of the scheme was proved in theory. The influence of the initial volume and initial pressure of the nitrogen room on the energy of cylinder rod was analyzed, and the conclusion is obtained that the ratio of nitrogen change ΔV and the initial volume V (0max) of nitrogen chamber should be 0.24.