The use of hoses for concrete pumping at concrete pumps should be carried out in relation to the criteria of both pressure and pumping distance. Concrete pumping hoses available on the market do not always meet the pressure criteria for stationary pumps or high pressure systems. It should be remembered that the maximum pressure in the working systems of boom pumps oscillates around 80 – 85 bar, depending on the machine model. Consequently, concrete pumping hoses should have a working pressure of 85 bar. This is indicated by the burst pressure parameter of 170 bar at the 2:1 safety factor. Hoses with an unknown working pressure parameter should not be used for such machines. This is especially important when the concrete pump pumps a concrete mixture through a boom and is connected, via a double-sided hose, to a further stationary pipeline.
Quality assessment of concrete pumping hoses. .
Machines with low pressure parameters – such as truck mixer concrete pumps, where the working pressure for some models is from about 50 bar to 65 bar can use hoses with a working pressure of 75 bar or 70 bar. For each case, it is important that the hose is not permanently broken. That it does not have broken and damaged internal reinforcement with steel mesh. It is not possible to treat end hoses (so-called pouring hoses) as less important in terms of quality. They must meet the same criteria and requirements as double-sided hoses. Users should not underestimate the fact that the occurrence of a stopper on the end hose is as probable as the occurrence of a plug on the steel pipeline of the pump.
Requirements when using hoses.
Concrete pumping hoses should meet the basic length requirements imposed by concrete pump manufacturers. It is necessary to use hoses with a length compatible with the length of the given boom model. As standard lengths of end hoses – 3-meter and 4-meter hoses are considered on one side. It is unacceptable to use 6-meter hoses or longer hoses for the concreting of high-pillar poles or high reinforced concrete structures. For such cases, it is necessary to run the final hose, eg through a construction crane.
When using hose to connect the boom’s pipeline to the stationary pipeline, it is necessary to determine the conditions for connecting the pump pipeline to the stationary pipeline. If the stationary pipeline is a vertical pipeline at the connection point – it is necessary to use a hose with a maximum length of 3 or 4 meters. A hose of any length can be used for connecting a horizontal pipe. However, changing the position of the stationary pipeline (for example when pumping concrete on the flooring) should not force the need to pull the long hose with the pump boom.
The company POLMIX-AST provides concrete pumping hoses manufactured by the M-FLEX CONCRETE PUMPING group, characterized by a working pressure of 85 bar and can be supplied in various diameters (from 2.5 “to 5”) and in various lengths, as factory prewired cables with system connections according to the VICTAULIC series.