| 摘要 |
A pile hammer for driving pipe-shaped foundation reinforcement piles (3) is of a so-called snap hammer type, i.e. equipped with an impact piston (1) designed to be inserted into the pile cavity (4) with an elongated section (1). According to the invention, the upper part of the impact piston is equipped with wider impact section (2) intended to lie against the upper edge (3a) of the pile, and the elongated impact piston section (1) is shorter than the pole's cavity (4) so that the impact force is transferred to the pile directly via the impact section (2). Using the invention the following can be achieved: the duplex hammer can be have a large length, but still have a small effective building height, and a favourable mass relation ship between impact piston volume and total impact device weight. The snap hammer is particularly appropriate for pile driving in confined spaces.<IMAGE> |
