| 摘要 |
<p>A method and apparatus for providing a substantially void-free tape wrapping around a pipe 1 having a longitudinal weld bead II protruding from the surface thereof. While the pipe 1 is simultaneously advanced and rotated, liquid viscous sealing material is applied to the pipe, and the applied sealing material is then doctored by means of at least one doctor blade in doctoring station 5. The doctor blade faces the advancing pipe surface, with the axis of the doctor blade at an angle of about 10° to 50° to the axis of the pipe 1, and is urged against the pipe 1 so that it is resiliently deformed by the pipe 1 and acommodates passage of the weld bead 11 underneath it. In this way the doctor blade doctors the sealing material so that it provides a smooth transition between the weld bead 11 and the adjacent pipe surfaces. The tape 61 is then spirally wrapped around the pipe 1. The invention is particularly useful when a heated sealing material, eg. a hot melt adhesive, is applied to a heated pipe which is subsequently wrapped with a heated polymeric tape having the same sealing material on its interior surface.</p> |
