Process for forming a polymeric coating on the outside surface of a length of tubing

US4390569A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Wolfgang Heinrich · Berlin, DE
• Klaus-Dieter Hammer · Mainz, DE
• Max Bytzek · Naurod, DE

Key dates

• Filing date: Mar 26, 1981
• Grant date: Jun 28, 1983
• Expiry date: Mar 26, 2001

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B05D2254/02
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Disclosed is a process for coating the outside surface of a length of tubing comprising the steps of coating the outside surface of the tubing with an initial layer of coating liquid, transporting the coated tubing along its longitudinal axis in a substantially vertically upward direction; passing the coated tubing through a constriction of predetermined width to reduce the thickness of the initial layer and form a thin layer of desired thickness on the outside of the tubing; leveling the thin layer without reducing the weight per unit area of the thin layer to form a layer of uniform thickness; and exposing the tubing to heat of a sufficient temperature to solidify the coating liquid and form an uninterrupted film of uniform thickness on the outside of the tubing.