Patent DE-102008012643-A1 (DE)
Title: Coating internal surface of molded article for contacting with flow-through fluid, comprises inserting the article, which comprises first and second front surfaces, into lockable container, and contacting second surface with coating fluid
Inventor: LUETZERATH STEPHAN
IPC: B05D7/22
Filed: 2008-03-05
Abstract: The method for coating internal surface of a molded article (8) for contacting with a flow-through fluid, comprises inserting the article, which comprises a first (12) and a second front surface (13), into a lockable container, where a first chamber (2) is formed with an adjustable first pressure and a second chamber (4) is formed with a second pressure, contacting the second front surface of the molded article with a fluid (10) provided for coating, where the molded article is present itself in the second chamber, and adjusting the second pressure in the second chamber. The method for coating internal surface of a molded article (8) for contacting with a flow-through fluid, comprises inserting the article, which comprises a first (12) and a second front surface (13), into a lockable container, where a first chamber (2) is formed with an adjustable first pressure and a second chamber (4) is formed with a second pressure adjustable independently from the first pressure after insertion of the molded article and locking of the container, contacting the second front surface of the molded article with a fluid (10) provided for coating where the molded article is present itself in the second chamber, and adjusting the second pressure in the second chamber so that the second pressure is greater than the first pressure in the first chamber and the difference of pressure is sufficient in order to flow the fluid for coating through the molded article. The molded article is inserted in such a way that a fluid of the second chamber flows through the molded article to the first chamber. The coating fluid flows through the molded article to a first pre-determined value and then the second front surface is separated from the coating fluid and the second pressure in the second chamber is kept at a value above the first pressure in the first chamber until the coating fluid present in the molded article is passed to a second pre-determined value. The coating fluid in the second chamber is supplied into a further container and the distance of the further container to the molded article is changeable on a control instruction. The flow of coating fluid is measured by a time-of-flight camera, by a Roentgen camera, by determination of the acoustic resonance of the gas column, by electrical conductivity measurements and/or by electrical resistance tests. The first pressure in the first chamber and/or the second pressure in the second chamber oscillate around a pre-determined value. The fluid front of the fluid is subjected with sound waves during its passage through the molded article. The second pressure in the second chamber is adjusted to a pre-determined time in such a way that the second pressure is smaller than the first pressure in the first chamber and the difference of pressure (0.01-10%) is sufficient, in order to flow the fluid intended for coating against the previous direction of flow. An independent claim is included for a device for the coating of the internal surface of a molded article.