Dosing pump unit

摘要

The unit has a dosing pump, where inlet side of the pump is connected with a connection and its outlet side is connected with a pressure pipe. A check valve pre-stressed against fluid pressure produced from the pump is arranged in the pressure pipe. A return pipe in flow direction of the reducing agent is connected with the pressure pipe before the valve. A stop valve (12) is arranged in the return pipe for selectively closing the return pipe.