PLATE HEAT EXCHANGER Russian patent published in 2016 - IPC B23K1/19 B23K35/30 B21D53/04 

FIELD: heat engineering.

SUBSTANCE: invention can be used for producing a permanently joined plate heat exchanger (1). Heat exchanger plates, having a solidus temperature above 1,100 °C, is provided beside each other to form plate package (3). Each heat exchanger plate comprises heat transfer area (10) and edge area (11), comprising bent edges which extend around the heat transfer area. Heat exchanger area (10) comprises a corrugation of elevations and depressions. On at least part of first convex surface (16) of a first plate, the melting depressant composition comprising a melting depressant component that comprises at least 25 wt% of boron and silicon. Plates are stacked into a plate package bringing second concave surface (17) into contact with the melting depressant composition on first convex surface of the first plate. Plates are heated to a temperature above 1,100 °C for melting the surface layer of the first convex surface of the first plate together with the melting depressant component and for forming a molten metal layer at the contact points between the first plate and the seconde plate. After solidification of said layer, joint is formed at contact points between plates and such that the bent edges form a tight fit between the bent edges of the plates.

EFFECT: invention provides tight joint between heat exchanger plates.

33 cl, 10 dwg, 15 tbl