Gravel pump

摘要

The gravel pump has a pump body with a suction opening on the base, a piston moving axially within the body dividing it into upper and lower working chambers (6,7), a piston valve (8) working between these chambers and a piston rod (9) extending outside the pump body. On the side of the piston facing the lower working chamber, or in the lower working chamber itself, a pressure balancer is provided to limit the vacuum that can be generated there. This is integrated into the piston and, for it, at least one air or gas cushion is provided. Also for this, a pipeline is provided joining the lower working chamber with the atmosphere.