Anordnung und Kraftverlauf von Zwischenpressstationen beim Rohrvortrieb
In the animation the required jacking forces at the main jacking station (blue) and at the intermediate jacking station (green, red) are presented in dependence on the jacking advance. The required force at the main jacking station grows with each newly installed pipe, because the length of the pipe string which is to be pushed and thus the skin friction grows correspondingly. If an intermediate jacking station, which has been installed before, is activated, it takes over the jacking force for pushing the pipes running in front of it. The required jacking force for the main jacking station decreases abruptly by exactly this degree, but increases again with each newly installed pipe. This process repeats itself with each activation of an intermediate jacking station. The intermediate jacking stations always push the same number of pipes independent from the construction advance, so that the required jacking force there remains constant to a large extent. The aim usually is to arrange the intermediate jacking stations in a particular way so that the maximum values of all jacking stations reach one power level.