| 摘要 |
Apparatus for lining bore holes with lining material, for example cement or concrete, comprises a spray head, means to drive the head through the hole and means for delivering lining material to the head, the head has an annular chamber into which the lining material is fed and from which the lining material is delivered to a rotatable spray disc or arm in an annular ring, an impeller is mounted in the annular chamber, the blades of which extend through the annular ring and into contact with the spray disc or arm. The apparatus is suitable for lining horizontal, inclined or vertical holes. |
