| 摘要 |
<p>The invention covers the process, the installation and, with the same means, the prior preparation of an inner surface of a pipe (15) having elbows or branches or changing diameters, with a view to the subsequent deposition of a coating of the paint, varnish or similar type. The process is characterised in that there is deposited at the inlet of the said pipe (15), and on its inner surface, a liquid layer of the treatment medium, stripping solution, degreasing solution, paint solution or the like, in the form of a liquid ring, and in that this ring is forced to move along the surface with a helical displacement. The displacement of the said sheath is effected by a current of air exerting two actions: a translational action and a rotational action enabling the liquid sheath to be kept permanently "applied" in intimate contact with the surface to be treated. The installation is characterised in that it comprises, at the inlet of the pipe to be treated, a spraying (8), centrifugation (13) and ventilation (2) station permitting the formation of the liquid ring and the displacement of the said ring in a helical movement, remaining permanently in contact with the inner surface, including in the elbows or branches. The chemical stripping, degreasing or similar solutions are recovered at the outlet of the pipe and are recycled in a closed loop. The excess coating solution is recovered in a tank (16).</p> |
