Patent ID: 6216774
Filing Date: 2001-04-17
Classification: F28D,F28F

Abstract:
A heat exchanger formed from a folding plate blank (21) comprising a plurality of first quadrilateral heat-transfer plates (S1) and a plurality of second quadrilateral heat-transfer plates (S2) which are alternately connected together through first and second folding lines (L.sub.1 and L.sub.2), said folding plate blank (21) being folded in a zigzag fashion along said first and second folding lines (L.sub.1 and L.sub.2), thereby defining axially extending high-temperature and low-temperature fluid passages (4 and 5) alternately in a circumferential direction,wherein radially outer peripheral walls (6, 80 and 100) are brazed to said plurality of first folding lines (L.sub.1) located on a radially outer side and radially inner peripheral walls (7, 8i and 10i) are brazed to said plurality of second folding lines (L.sub.2 ) located on a radially inner side, thereby closing radially outer and inner peripheries of said axially extending high-temperature and low-temperature fluid passages (4 and 5), said high-temperature passages and said low-temperature passages being substantially parallel each other, while defining high-temperature fluid ducts (13 and 14) connected to said high-temperature fluid passages (4) and low-temperature fluid ducts (17 and 18) connected to said low-temperature fluid passages (5);wherein a high-temperature fluid passage inlet (11) and a high-temperature fluid passage outlet (12) are formed in openings at axially opposite ends of said high-temperatures fluid passages (4); andwherein projection stripes (24.sub.f and