| 摘要 |
<p>A stationary frame is positioned in surrounding relation with the surface of a polyethylene conduit to be prepared for scraping preliminary to performing electrofusion on the conduit by a keyhole operation in an excavated underground location. A scraper tool is mounted on the frame in a fixed longitudinal position to rotate around the surface of the conduit. A cutting blade of the scraping tool extends longitudinally a preselected length on the conduit into contact with the surface of the conduit. Rotation of the scraper tool carries the cutting blade completely around the surface of the conduit to remove a uniform layer of material from the surface of the conduit. Any out of roundness existing in the conduit is removed before the scraping operation is commenced. Uniform compression is applied by split clamps surrounding the conduit. Compression of the clamps restores the conduit to a concentric configuration preliminary to the electrofusion operation.</p> |
