Concrete pumps are of several types nowadays; for example, some have robotic arms and are remote-controlled while others are not remote-controlled. However, the mechanism of functioning is the same for all of those, which is to transfer concrete to the construction point by pumping it. The concrete being transferred is in liquid state. It is not necessary to use new machines for this task and even used concrete pumps can perform it perfectly.
Seeing the relevance of such used machinery in the field of construction, many retailers have become active in selling it. For example, Singapore-based Silk Road sells a wide variety of construction machinery.