CORROSION RESISTANT BIMETALLIC TUBE AND APPLICATION IN ITS TUBE BUNDLE UNIT

摘要

PPROBLEM TO BE SOLVED: To provide a suitable bimetallic tube for the tube bundle unit of heat exchanger, the unit which is operated under the high pressure condition and the high aggressive condition of erosiveness and corrosiveness. PSOLUTION: The unit consists of at least one tubular part of the first metal which is tolerant to the corrosive and/or erosive action of the treated fluid in contact, and the tubular component is a bimetallic tube having a near area to one covered end with the second metal layer at least or the distal end when the exterior is seal welded to the different support body from the first metal. Moreover, the tube bundle unit is used for handling the heat exchanger in high temperature and high pressure under the conditions of high aggressive treated fluid, and the tube bundle contains at least one tube having the above characteristics. The unit is used especially as a dissolution unit in a cycle of the heat exchanger mechanism and a urea composition process of high pressure, high temperature, and high aggressive condition of the treated fluid, and the tube bundle contains at least one tube having the above characteristics. PCOPYRIGHT: (C)2008,JPO&INPIT