Sleeve type heat exchanger

Abstract

A sleeve type heat exchanger comprises an inner pipe, an outer pipe and an annular connecting plate, the inner pipe is a corrosion-resistant pipe, the outer pipe is a steel pipe, the annular connecting plate is formed by compounding a corrosion-resistant layer and a steel base layer, and the annular connecting plate is arranged between the inner pipe and the outer pipe in a sleeved mode. The corrosion-resistant layer is annularly welded with the outer wall of the inner pipe, the inner wall of the outer pipe is annularly welded with the steel base layer, and an annular space between the inner pipe and the outer pipe is blocked through an annular connecting plate. The casing pipe is composed of the steel outer pipe and the corrosion-resistant inner pipe, the steel outer pipe and the corrosion-resistant inner pipe are connected in a welded mode through the annular composite connecting plate, the process requirement that welding must be conducted between the same materials is met while the using requirement is met, and the connecting strength of the connecting plate and the inner pipe and the connecting strength of the connecting plate and the outer pipe are guaranteed. And the material cost of the product is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchangers, in particular to a shell-and-tube heat exchanger. Background Art

[0002] The basic structure of a shell-and-tube heat exchanger is to sleeve two circular tubes with different diameters together. One fluid flows in the inner tube, and the other fluid flows in the circumferential gap between the inner tube and the outer tube. A connecting plate is welded between the inner tube and the outer tube to seal the circumferential gap and ensure the flow of the fluid in the outer tube. Since welding must be carried out between the same materials, the inner tube, the outer tube, and the connecting plate must be made of the same material to ensure normal welding and the connection strength between the connecting plate and the inner tube and the outer tube.

[0003] When a fluid with strong corrosiveness needs to be introduced into the inner tube, corrosion-resistant materials such as titanium or zirconium materials are required. When cooling or heating the fluid in the inner tube, a fluid with weak corrosiveness, such as water, is introduced into the circumferential gap. Therefore, the outer tube is generally made of steel. Since steel cannot be welded to titanium or zirconium materials, in general engineering designs, the material selection of the outer tube is the same as that of the inner tube, and the material selection of the connecting plate between the inner tube and the outer tube is also the same as that of the inner tube. Its biggest defect is that the fluid in contact with the outer tube has weak corrosiveness, and it is completely unnecessary to use titanium or zirconium materials, resulting in a significant increase in material costs due to the necessity of selecting titanium or zirconium materials for the outer tube. Summary of the Invention

[0004] The utility model provides a shell-and-tube heat exchanger to overcome the deficiencies of the prior art.

[0005] The technical solution adopted by the utility model is as follows: a shell-and-tube heat exchanger includes an inner tube, an outer tube, and an annular connecting plate. The inner tube is a corrosion-resistant tube, the outer tube is a steel tube, and the annular connecting plate is composed of a corrosion-resistant layer and a steel base layer. The annular connecting plate is sleeved between the inner tube and the outer tube, and the corrosion-resistant layer is annularly welded to the outer wall of the inner tube, and the inner wall of the outer tube is annularly welded to the steel base layer. The annular space between the inner tube and the outer tube is sealed by the annular connecting plate.

[0006] The annular connecting plate is arranged at both ends of the outer tube, and the steel base layer is located on the outside and the corrosion-resistant layer is located on the inside.

[0007] The corrosion-resistant layer and the steel base layer are compounded by the explosion welding method.

[0008] The corrosion-resistant layer and the steel base layer are made by the rolling composite method.

[0009] The corrosion-resistant tube is a titanium tube, and the corrosion-resistant layer is a titanium coating.

[0010] The corrosion-resistant tube is a zirconium tube, and the corrosion-resistant layer is a zirconium coating.

[0011] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0012] The casing of the present utility model is composed of a steel outer tube and a corrosion-resistant inner tube, and the steel outer tube and the corrosion-resistant inner tube are welded and connected through an annular composite connecting plate, which meets the use requirements and realizes the process requirement that welding must be carried out between the same materials, ensures the connection strength between the connecting plate and the inner tube and the outer tube, and greatly reduces the material cost of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic structural diagram of an embodiment of the present utility model;

[0014] Figure 2 is Figure 1 a partial enlarged schematic view of part A in DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following will Figure 1-2 be described in detail with reference to the accompanying drawings

[0016] and specific embodiments of the present utility model.

[0017] Specifically, the inner tube 1 is a titanium tube, the outer tube 2 is a steel tube, the annular connecting plate 3 is composed of a titanium cladding layer 3-1 and a steel base layer 3-2, and the steel base layer 3-2 is located on the outside (towards the pipe orifice direction), and the corrosion-resistant layer 3-1 is located on the inside (away from the pipe orifice direction). The titanium cladding layer 3-1 and the steel base layer 3-2 are compounded by explosive welding or rolling compounding. The above-mentioned explosive welding and rolling compounding are both prior arts and will not be elaborated here.

[0018] During specific implementation, first, the annular connecting plate 3 is sleeved on the titanium tube with the titanium cladding layer 3-1 facing inwards, and then the outer wall of the titanium tube is welded to the titanium cladding layer to form an annular weld according to the existing welding process. After welding, the weld is subjected to PT inspection and evaluated according to the standard of NB / T47013.5-2015. After passing the inspection, the steel tube is sleeved on the outer periphery of the annular connecting plate 3, and the inner wall of the steel tube is welded to the steel base layer 3-2 to form an annular weld through the pipe orifice according to the existing welding process. After welding, the weld is subjected to MT inspection and evaluated according to the standard of NB / T47013.4-2015. After passing the inspection, the annular space between the inner tube 1 and the outer tube 2 is blocked by the annular connecting plate 3. Finally, the ends of the outer tube 2 are interconnected through the connecting pipe 4, so that the annular space is continuously penetrated.

[0019] During use, a fluid with relatively strong corrosiveness is passed through the inner tube, and a fluid with relatively weak corrosiveness that flows in the reverse direction, such as water, is passed through the circumferential space, so as to cool or heat the fluid in the inner tube.

[0020] Embodiment 2: The basic structure, welding process and usage method are the same as those in Embodiment 1, the difference being that the inner tube 1 is a zirconium tube, the annular connecting plate 3 is composed of a zirconium cladding layer 3-1 and a steel base layer 3-2, and the zirconium cladding layer 3-1 is annularly welded to the outer wall of the inner tube 1, and the inner wall of the outer tube 2 is annularly welded to the steel base layer 3-2. The zirconium cladding layer 3-1 and the steel base layer 3-2 are compounded by an explosion welding method or made by a rolling composite method.

[0021] The utility model solves the difficult problem of how to connect the outer tube and the inner tube in the case where the inner tube is a titanium tube or a zirconium tube and the outer tube is a steel tube. It can not only meet the use requirements, but also greatly reduce the cost.

[0022] The above embodiments are only the preferred embodiments of the utility model, and are not used to limit the scope of implementation of the utility model. Therefore, all equivalent changes made according to the content described in the claims of the utility model should be included within the scope of the claims of the utility model.

Claims

1. A tube-in-tube heat exchanger, comprising an inner tube (1), an outer tube (2) and an annular connecting plate (3), characterized in that: The inner tube (1) is a corrosion-resistant tube, the outer tube (2) is a steel tube, the annular connecting plate (3) is composed of a corrosion-resistant layer (3-1) and a steel base layer (3-2), and the annular connecting plate (3) is sleeved between the inner tube (1) and the outer tube (2), and the corrosion-resistant layer (3-1) is annularly welded to the outer wall of the inner tube (1), and the inner wall of the outer tube (2) is annularly welded to the steel base layer (3-2), and the annular space between the inner tube (1) and the outer tube (2) is sealed by the annular connecting plate (3).

2. The shell-and-tube heat exchanger according to claim 1, wherein: The annular connecting plate (3) is arranged at both ends of the outer tube (2), and the steel base layer (3-2) is located on the outside and the corrosion-resistant layer (3-1) is located on the inside.

3. The tube-in-shell heat exchanger according to claim 1, wherein: The corrosion-resistant layer (3-1) and the steel base layer (3-2) are compounded by the explosion welding method.

4. The shell-and-tube heat exchanger according to claim 1, wherein: The corrosion-resistant layer (3-1) and the steel base layer (3-2) are made by the rolling composite method.

5. The shell-and-tube heat exchanger according to claim 1 or 2 or 3 or 4, characterized in that: The corrosion-resistant tube is a titanium tube, and the corrosion-resistant layer (3-1) is a titanium cladding layer.

6. The shell-and-tube heat exchanger according to claim 1 or 2 or 3 or 4, characterized in that: The corrosion-resistant tube is a zirconium tube, and the corrosion-resistant layer (3-1) is a zirconium cladding layer.

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