You can see them again and again on construction sites: electric concrete pumps that pump the fresh concrete into the prepared formwork. Surely one or the other technically interesting do-it-yourselfer will ask himself how such a concrete pump works at all.
We, therefore, explain the function and structure of a concrete pump here.
Concrete Pump Distinctions:
Regardless of the type of concrete pump, there are only two different types of pumps that can be used as concrete pumps:
- Piston pumps
- Rotor pumps
Both types of concrete pumps differ significantly in terms of how they work. Therefore, the choice of one or the other pump depends primarily on the specifications of a construction project.
Piston Pumps:
A reciprocating piston conveys the fresh concrete. During the stroke to the bottom dead center, a negative pressure is created, whereby the fresh concrete is sucked out of the mixer. The outlet hose is now opened via a sliding gate and the fresh concrete is pumped into the transport hose when it is lifted to the top dead center.
Advantages And Disadvantages:
Due to the gate valves, this concrete pump is more complex in construction and also mechanically vulnerable in this area. Depending on which slides are used, they close almost tightly, which is why water (e.g. for cleaning) can also be pumped.
Rotor Pumps:
The rotor pump is a simpler concrete pump system. A vacuum pump generates negative pressure so that fresh concrete is sucked out of the mixer. The concrete is guided around the pump in a flexible hose, with two rollers exactly opposite that compress the flexible hose.
The Function Of The Rotor Concrete Pump:
In this way, the negative pressure in front of the rollers always remains constant. This in turn results in an even flow of fresh concrete. The speed of the vacuum pump can be infinitely adjusted via a gearbox that can be connected to a combustion engine or an electric motor. In this way, the pump output can be infinitely adjusted.
