Apparatus for pumping of fluid materials and use thereof for spraying concrete

摘要

Pumping apparatus of the type comprising twin cylindrical pumping chambers (1) and (2) alternately sucking up and discharging the material to be pumped, sucking up taking place through orifices (3) and (4) formed in the common supply chamber (5), and delivery taking place via a delivery pipe (8) moved towards the orifice of the chamber which is to deliver. Pumping is carried out by pumping pistons (6) and (7) controlled hydraulically formed in the chambers (1) and (2), the hydraulic circuit being laid out to make sure that the pumping piston of the material-intake chamber arrives at the total filling position before the delivery chamber arrives in the total delivery position. In another embodiment, the pumping apparatus comprises "balance arm effect" means in which the pumping speed automatically increases in order to compensate for the drop in flow rates due to the time necessary for the delivery pipe to move from one orifice to the other. The apparatus provides exceptional flow rate without pulsing and is particularly useful in apparatus for spraying or splashing concrete. IMAGE