Casing machine
A casing machine drives steel drill pipes hydraulically into the subsoil. The drill pipe is moved by a hydraulic-mechanical clamping device, a clamp, by turning the drill pipe back and forth at an angle of rotation of approx. 25 ° to 30 ° and applying vertical feed forces.
description
Casing machines are used in particular for well drilling and the production of in-situ concrete piles with cable excavators and drill grabs. The roughing machine is attached to the undercarriage of the duty cycle crane to absorb reaction forces. The hydraulic supply is usually provided by a separate hydraulic unit .
Casing machines are also used in combination with rotary drilling rigs if the torque of the drill drive and the feed force are insufficient to overcome the skin friction between the drill pipe and the soil, or if the casing can no longer be pulled with the retraction force of the device. The hydraulic supply is then mostly provided by the carrier. The drilling rig and casing machine are not operated at the same time.
A variant of casing machines are tube lathes. Like the rotary drilling rigs, these drive the drill pipe into the subsoil by means of a continuous rotary movement and the application of vertical thrust forces. An invention by Theo Fromme and Josef Roob, for which a patent was applied for at the German Patent Office in 1995 , manages without an external hydraulic unit. This device directs the torque of the power head via the Kelly bar directly into the tube lathe.
See also
literature
- Jörn M. Seitz, Heinz-Günter Schmidt: Bored piles . Ernst & Sohn Verlag, Berlin 2000, ISBN 3-433-01308-X , p. 192ff