| 摘要 |
<p>Device used in the production of bored pile comprises a continuous screw (1) surrounded almost over its entire screw length with a rotating sleeve tube (3). During boring, the sleeve tube is rotated in or against the direction of rotation of the screw, and the screw and the sleeve tube are simultaneously inserted in the ground. To facilitate material removal, the surface roughness of the screw surface (2) facing in the conveying direction is partly or completely increased relative to the roughness of rolled surfaces by additional processing. The increased surface roughness extends at least over the screw length necessary for conveying. Preferred Features: The surface roughness is produced by punctiform or linear elevations and/or recesses produced by welding, burning, rolling, pressing, drilling, stamping or metal-cutting processes at least on the surface facing in the conveying direction.</p> |
