Abstract: The invention relates to a turning mechanism for driving in or extracting piles by means of tangential rotary blows being imparted by a rocker arm equipped with balance weights and arranged in a rotary manner relative to the pile. In order to render superfluous the hitherto necessary noise-damping, additional damping means, damping members made from an incompressible, elastic material are used, which are placed in recesses in at least one stop of a pair of stops in such a way that there is a deformation, particularly at right angles to the impact direction, which is within the elastic limit of the member and prevents direct contact between the stop pairs. These members are arranged on all parts of the rocker arm which, in operation, form noise sources.

Abstract: A drilling grab for pile foundations and well boreholes wherein the drilling grab comprises a grab body supporting circular grab spades which tilt from an open position to a closed position about pivot pins carried by the grab body. A radially projecting abutment interchangeably connected to the outer periphery of the grab body is engageable with the back of the grab spades when the same are in an open position. The abutment overlaps the periphery of the grab body and is characterized in that they consist of extension members adapted to grab spades of different sizes. The members are supported on radially projecting ribs located on the grab body.