GB620097A - Improvements relating to heat interchange apparatus - Google Patents

Abstract

620,097. Tubular heat-exchangers; temperature - responsive actuating - elements. SERCK RADIATORS, Ltd., and GARNER. E. Jan. 4, 1947, No. 339. [Classes 64(ii) and 64(iii)] [Also in Group XXVI] In a heat-exchanger of the kind in which an assembly of parallel tubes is surrounded by a shell within which baffle plates are arranged to guide a liquid, e.g. oil, over the tubes, a thin metal strip 3 or each of a plurality of strips is attached at one edge to the edge of a baffle 1 and at the free edge is pressed into tight contact with the inner surface of the shell 2 by the pressure of the liquid within the shell. In the form shown in Fig. 1, the free edges of the strip are formed into flexible tongue pieces by means of equally spaced slits 5. Two such strips may be used one above the other with the tongues of one overlapping the slits of the other. In another embodiment, two strips having relatively broad notches are placed one above the other and the plain pieces in one strip are embossed and lie opposite and within the notches of the other strip. The fixed edges of the strips may be embraced by a folded flange of a third or projecting plain strip. The strips may be attached to the baffle by bending the edge in the form of a clip or the edge may be folded back and doubled to form a flange 4 which is inserted in a complementary groove in the periphery of the baffle. When it is desired to by-pass the flow path when the oil flowing over the tubes is cold and viscous, the strip or strips are of bi-metallic construction and when the temperature of the oil rises sufficiently, the tongue pieces bend towards the shell in response to the heating action of the oil and are then pressed into close contact with the shell by the pressure of the oil. In one embodiment, Fig. 3, two bi-metallic strips 14. 15 are used, each comprising a layer of steel united to a layer of brass, the fixed edges of the strips being enclosed within the fold 16 of a third or projecting strip 17 which is inserted and gripped within a groove in the edge of the baffle I. In a further embodiment, a single bimetallic strip may have the brass layer severed by parallel transverse slits and the free edge of the strip may be folded over to form a bead. The embodiments described can be used for straight longitudinal or circular transverse baffles.