One of the unique features of the IHC Hydrohammer design, besides its sturdiness and high level of controllability, is its ability to facilitate extraction of earlier driven casings.
Fort exctraction a special clamp system rigidly connects the pile head and the hammer housing. Line pull from the crane is transferred tot he pile via the clamp. High frequency operation of the hammer with extremely low energy per blow reduces frictional resistance, enabling pile extraction at crane loads significanly lower than used for conventional static pulling.
Under extemely difficult circumstances it is even possible to generate an additional upward force by impacting the hammer housing in an upward direction. This can set a jammed pile into motion.
This combination of features means that only one hammer is needed for both driving and extracting, making them ideal for handling cast-in-situ (vibro) piles.
