An apparatus for an uninterrupted casting of concrete into bore holes or the like for the construction of foundation pillars and fed through a system of telescopic pipes fluide dynamically operable

摘要

A transportable apparatus comprising a framework (1) supporting by means of hydraulic jacks (7) a pipe telescopic system, to be moved up or down, in its collapsed condition. The telescopic system (3) comprises telescopically connected coaxial pipes (3a, 3b,...) defining in combination, a duct (30) open at its ends for casting concrete, in a bore hole (2). Each of the pipes, the last excepted, is formed by two coaxial walls (15, 15 min ; 14, 14 min ,...) and by an upper sidely extending outwards head (28b, 28c,...) forming annular chamber upstream the head (28, 28c,...) and pairs of annular chambers (29a, 29a; 29b min , 29b min ;...) downstream of the respective head. Said chambers are open at their opposite end and respectively house the head of the subsequent pipe and at least a variable portion of this latter, means are provided for feeding a pressurized fluid into the chambers (11, 28b, 28c,...) or alternatively in the chambers (29a, 29a; 29b min , 29b min ;...), which act together with the heads (28b, 28c,...) as double acting annular cylinders and pistons, for performing the elongation or collapse of the pipe telescopic system.