TH72178A - Two-tube heat exchanger and how the heat exchanger is manufactured - Google Patents

Abstract

DC60 (01/03/48) is a simple fabricated double-tube heat exchanger that can be easily bent in all directions to fit some of the piping layouts. The inner tube (1) has a cross-section perpendicular to the axis. More than one balloon-shaped convex (3) is formed, protruding radially from the center and centrally connected to each other on the axial cross-section. The circumference of the convex (3) is bent into a waveform, the crest (9) of which is tangent to the inner surface of the outer tube (2). In this state, external forces act on the inner tube (1) and the outer tube (2), causing the entire tube to bend. An external force is applied to the inner tube (1) and the outer tube (2), causing the entire body to bend.

Claims (6)

1. A double-tube heat exchanger has an inner tube (1) fitted with an outer tube (2). On the inner tube (1), viewed from a cross-section perpendicular to the axis, there are more than one balloon-shaped convex (3) radially protruding from the center, which are interconnected. The width of each convex (3) is widest at the center from the center to the radial ends and gradually narrows at both ends. At the center, there are more than one groove (10) radially outside. On each convex (3), the axial cross-section is bent into a wave shape. The longest radial end of each convex (3), which is the apex (9) of each wave, touches the inside of the outer tube (2). In the condition that the inner tube (1) is fitted with the outer tube (2) and the axis is bent, fluid 1 (4) flows inside the inner tube (1), while fluid 2 (5) flows between the inner tube (1) and the outer tube (2). 2. From claim 1, it is a double-tube heat exchanger with the aforementioned convex section (3), with only the outer ends of the aforementioned balloon-shaped section radially in contact with the inner surface of the outer tube (2) mentioned above. 3. From claim 1 or from claim 2, a double-tube heat exchanger is constructed with open ends (6) at both ends along the axis of the inner tube (1) welded around to the inner surface of the outer tube (2). At the outside of both ends of the outer tube (2), a pair of inlet/outlet channels (7) are constructed for fluid 1 (4). At both ends of the outer tube (2), a flange (8) is constructed for connection. It is used as an EGR cooler, allowing engine exhaust as fluid 1 (4) and coolant as fluid 2 (5) to flow through. 4. From claim 1 or from claim 2, a double-tube heat exchanger is constructed with open ends (6) at both ends along the axis of the inner tube (1) is welded around to the inner surface of the outer tube (2). At the outside of both ends of the outer tube (2), a pair of inlet/outlet channels (7) are constructed for fluid 1 (4). At both ends of the outer tube (2), flanges (8) are constructed for connection. It is used as an oil cooler, with one fluid 1 or fluid 2 (5) being oil and the other being water. 5. From any one of the claims from Claims 1-4, it is a double-tube heat exchanger with an inner tube (1) as mentioned above, having a cross-section with a convex section (3) as mentioned above, shaped like a balloon, with the centers connected, forming a three-pronged clover shape overall. 6. A method for fabricating a double-tube heat exchanger under one of the claims 1-5 that involves a step in which an inner tube (1) is inserted into an outer tube (2) with the axial lines of both tubes aligned, so that each convex section (3) of the inner tube (1) has its wave crest (9) in contact with the inner surface of the outer tube (2), and a step in which the edges of the open ends (6) at both ends along the axial line of the inner tube (1) are welded to the inner surface of the outer tube (2), and after which an external force is applied to the inner tube (1) and the outer tube (2) causing the axial lines to bend.