METHOD OF MANUFACTURING A TUBE GRID AND A HEAT EXCHANGER UNIT FOR A BASIN REACTOR OR A BASIN CAPACITOR AND A CONTRIBUTING TUBE GRID AND HEAT TRANSFER UNIT

摘要

The present application relates to a method for manufacturing a junction tube assembly (7) and a heat exchanger for a pool reactor or a pool condenser for use in the production of urea from ammonia and carbon dioxide, the method including making a tube grid (7) from carbon steel material and providing said pipe lattices (7) with anticorrosive protective layers (8, 9) of two-phase austenitic-ferritic stainless steel, while the heat exchanger contains at least one U-shaped pipe (13) of two austenitic-ferritic stainless steel, the method further comprising inserting at least two sleeves (11) of two-phase austenitic-ferritic stainless steel through the tube sheet (7), so that both ends of the sleeve (11) protrude from the tube sheet (7) , wherein the method further includes connecting the sleeves (11), at least their opposite ends, at least with the protective layers (8, 9) of the tube sheet (7) and, finally, connecting both ends of at least one U-shaped pipes (13) with corresponding sleeves (11).