The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 02, 1982
Filed:
Mar. 26, 1981
Wolfgang Heinrich, Salach, DE;
Max Bytzek, Wiesbaden, DE;
Klaus-Dieter Hammer, Mainz, DE;
Martin Schroder, Wiesbaden, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Disclosed is a process for forming an uninterrupted coating of uniform thickness on the inside of a length of tubing which comprises the steps of forming a loop of tubing with a downwardly inclined portion and an upwardly inclined portion; filling the cavity of the tubing forming the loop with a coating liquid; transporting the tubing along its longitudinal axis in a substantially vertically upward direction to coat the inside of the tubing, above the level of the coating liquid, with an initial layer of coating material; constricting the tubing to lay partially flat along a narrow zone running transverse to the direction of transportation above the level of the coating liquid to retain the greater part of the coating liquid in the constriction zone and form a thin layer of coating liquid of desired thickness on the inside; of the tubing issuing from the constriction zone; filling the cavity of the tubing issuing from the constriction zone with support gas; and exposing the tubing to the action of heat at a sufficiently high temperature to fuse the coating layer to the inside of the tubing and form an uninterrupted film of uniform thickness on the inside of the tubing. Also disclosed is an apparatus for carrying out the process of the present invention.