The Principle
If an ordinary intake socket is lowered into highly viscous material, the material will flow so slowly, that after short time, the pump will soak up air, because the socket is not fully covered by the material anymore. To avoid that, a plate, closing tight to the wall of the barrel by a soft sealing lip, is put on top of the material in the barrel. This plate is lowered slowly so that the material rises through a hole in the center of the plate into the intake socket. The pumped amount and the amount lifted through the plate have to be precisely the same. This has to be secured by appropriate control of the follower plate.
In such a device a scooping piston pump or an eccentric screw pump can be used for pumping the stiff paste.
Read more about this topic: Follower Plate Pump
Famous quotes related to the principle:
“The principle of the brotherhood of man is ... narcissistic ... for the grounds for that love have always been the assumption that we ought to realize that we are the same the whole world over.”
—Germaine Greer (b. 1939)