| 摘要 |
In a pressure head for pipe driving in soils, with an annular body which has a cylinder group serving as pressure members for the pipe line and having actuating pistons, the annular body (1), in order to create a large driving stroke, is provided with a first group of pressure members (2, 3) and has a second group of pressure members (6, 7) whose part which is variable in length acts firmly on a pressure ring (8) on the same axis. <IMAGE>
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