Pump system for pumping a substance

Abstract

The application relates to a pump system (100) for pumping a substance. The pump system comprises pumping cylinders (112) and a swing pipe mechanism (114). Each pumping cylinder (112) is configured to load the substance, when said pumping cylinder is open to operate as a loading cylinder, and to push the substance from the pumping cylinder (112), when said pumping cylinder is closed to operate as a pushing cylinder. The swing pipe mechanism is configured to open one of the pumping cylinders for loading the substance to said pumping cylinder (112) and to close another of the pumping cylinders for directing the substance from said pumping cylinder (112) outside the pump system. The swing pipe mechanism comprises a swing pipe (116) for each pumping cylinder (112) so that the swing pipe mechanism is further configured to keep the pumping cylinders closed by means of the swing pipes (116) to push the substance from the pumping cylinders simultaneously for a moment for preventing a decrease of a substance flow outside the pump system during a change of the pushing cylinder.