For pumping concrete, the structure of the concrete pump itself, the method of pipe layout, and the quality of the concrete are the fundamental factors that directly affect the pumping effect. The structure of the concrete pump must ensure that there is no segregation and large pressure loss when conveying concrete. The quality of concrete is the main factor, which is affected by the type of cement, the quality of coarse and fine aggregates, the mix ratio of concrete, the uniformity of mixing, the transportation distance, the transportation means, etc.
The blockage of the pumping pipeline is mainly caused by the slump of the concrete that does not meet the requirements and the large resistance of the pipeline inner wall. A condition necessary for pumping concrete is that under the action of pressure, the water, cement and fine sand in the concrete in the pumping pipeline form a lubricating layer of cement mortar on the wall of the pipe. The lubricating layer is surrounded by coarse aggregate , Fine aggregate, cement and water. Under the action of pumping pressure, the concrete makes a suspended movement along the pipe wall, forming a constant plug flow. This flow state of concrete is always maintained from the pump port of the concrete pump to the output of the end of the delivery pipe. On the contrary, the concrete that is not pumped smoothly is generally concrete with too much bleeding and poor workability. This kind of concrete will destroy the suspension movement.