Utility Tunnelling - Jacking steering, measurement and monitoring

Inclination and rolling

Prevention of rolling of the pipe string

Rolling is the rotation of jacking machines and jacking pipes around the jacking axis. In the case of circular cross-sections, these are harmless to the subsequent pipeline as they do not impair its function. During jacking, however, and especially in the case of long and curved jacking, this rolling can become problematic due to the installations in the pipe string.

In order to avoid rolling, plates are attached to the left and right on the jacking machine and on the trailing shield segments. These fix the jacking machine in position. Before entering the subsoil, the plates are removed. In addition, the jacking pipes can be equipped with bolts which are also intended to prevent the pipes from rolling.


Removal of the (rolling) plate by means of a welder. [Source: STEIN Ingenieure GmbH]


Smoothing the weld by means of an angle grinder. [Source: STEIN Ingenieure GmbH]

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