JPS59109786A - Heat exchanger - Google Patents

Abstract

PURPOSE:To prevent fluid on the primary side from mixing with the secondary fluid without being affected by the difference in quantity of expansion and contraction caused by the change in temperature, by providing a labyrinth seal consisting of disks having several grooves to an outer shell and an outer shroud, respectively. CONSTITUTION:The fluid on the primary side in the upper chamber 19 tends to flow into the lower chamber 20, because the pressure in the upper chamber 19 is higher than that in the lower chamber 20. The pressure loss in the joint part between the outer shell 1 and the outer shroud 4 can freely be determined by arbiterily controlling the gaps and the grooved forms in the labyrinth seal, which is constituted by a disk 17 having grooves, provided to the outer shell 1, and a disk 18 having grooves, provided to the outer shroud 4. Accordingly, excessive thermal stress caused by the difference in the quantity of expansion and contraction due to the change in temperature in the parts of a heat exchanger is prevented. In addition, the fluid on the primary side is prevented from being mixed with the secondary fluid, by providing the labyrinth seal between the outer shell 1 and the outer shroud 4.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a heat exchanger, and particularly relates to a downcomer tube arranged concentrically in a cylindrical container, and a plurality of heat transfer tubes arranged around the downcomer tube. This relates to a shell-and-tube heat exchanger consisting of, etc.

[Prior art and its problems] The conventional structure of a shell-and-tube heat exchanger and its problems will be explained with reference to FIG.

In Fig. 1, a primary side fluid inlet nozzle 2 and a primary side fluid outlet nozzle 3 are provided on the outer side 11i11.
1ii An outer shroud 4, an inner shroud 1-5, and a descending mass 6 are arranged concentrically. The inner shroud is connected to the downcomer pipe through a hemisphere 7 for calculating the difference in expansion and contraction due to the difference in temperature expansion.

A secondary side upper end plate 9 having a secondary side fluid outlet nozzle 8 is installed in the upper part of the outer shell, and a lower blemish 12 is suspended through a heat transfer tube bundle 11 connected to an upper tube plate 10. The dividing plate 14 installed in the F section Ii'/() connects the inner wall of the outer shell and the outer wall of the outer shroud. 1 after heat exchange with side fluid
It is fixed to prevent mixing with the next fluid. 15 is the primary fluid outlet window, and 16 is the primary fluid outlet window.

A simple explanation of the operation of a heat exchanger.

The temperature of the primary fluid is transferred from the primary fluid entry nozzle 2 to the outer shell 1.
and enters the outer shell 5 through the primary fluid inlet window 15. After that, it passes through the outside of the heat exchanger tube bundle 11 and
After exchanging heat with the next fluid, the primary fluid outlet window 16
The fluid flows out through the primary fluid outlet nozzle 3. On the other hand, the low-temperature secondary fluid is led from the downcomer pipe 6, reverses its flow direction by the lower blennium 12, passes through the tubes of the heat transfer tube bundle 11 from the lower tube plate 13, and exchanges heat with the primary fluid. The fluid flows out from the upper tube plate 10 to the secondary fluid outlet nozzle 8.

In such a heat exchanger, the crystallinity key yt5 of each part is complicated and the shape is very long, so the amount of expansion and contraction of the outer shell 1 and the outer shroud 14 due to changes in dryness + U is limited. I'm trying to make a difference. Therefore, excessive thermal stress will occur near the dividing plate 14 provided to prevent mixing of the primary fluid, and the structure of the heat exchanger 414 may suffer various damage ('+B There is.

[Purpose of the invention] This north gate was created to solve the above problems.
It is an object of the present invention to provide a heat exchanger that prevents mixing of primary side fluids without affecting the expansion/contraction m difference with respect to temperature changes.

[Summary of the Invention] According to this invention, the primary fluid before heat exchange and the primary fluid after heat exchange can be separated from each other in the radial direction or from the outer shell. By forming a labyrinth seal with a disk having several grooves in the longitudinal direction and a disk having several grooves provided opposite to the disk from the outer shroud, temperature changes can be prevented. A heat exchanger is achieved that can prevent mixing of primary fluids without being affected by the difference in expansion/contraction m between the two.

[Embodiments of the invention] The present invention will be described in detail below with reference to the drawings.

Figure 912 (Illustrating an embodiment of the labyrinth seal forming part, which can be installed as many as 100 times) to separate the primary fluid before heat exchange and the primary fluid after heat exchange according to the present invention. It is an enlarged cross-sectional view shown at -C.

The outer shell 1 and the outer shikoroud 4 are installed concentrically as in the conventional case. The outer shell 1 has two grooves running radially from the inner circumference! A disk (1) 17 is provided on the outer circumferential side of the external shroud 4 with an appropriate gap and a groove of Iζ2 (2>18) so as to mesh with the disk (1) 17 described above. [), forming a labyrinth seal.

[Effect of the invention] The effect of Mokuhokumon will be explained with reference to FIGS. 1 and 2.

Consider the pressure on the upper and lower sides separated by the dividing plate 14 in the conventional example shown in FIG. The primary fluid is led from the primary fluid inlet nozzle, and the primary fluid is introduced through the primary fluid inlet window 15.
, the heat exchanger tube bundle 11.The primary fluid outlet 1" passes through the window 16, etc., and θIL exits to the primary fluid outlet nozzle while undergoing various pressure losses during this time.

Therefore, the pressure on the upper side partitioned by the dividing plate 14 is higher than the pressure on the lower side. This shows that in the example of the present invention shown in FIG. 2, the pressure in the upper chamber 19 is higher than that in the lower chamber 20, and the primary fluid in the upper chamber V19 is
Let's try to flow into 0. Now, the layout of the labyrinth seal portion formed by the grooved disk (1) 17 provided on the outer body 1 and the grooved disk (2>18) provided on the external shikoroud 4 is explained. By adjusting and covering the groove shape as appropriate,
The pressure loss in this part can be determined freely. Therefore, if the pressure loss of this labyrinth seal part C is the same as the pressure loss at the primary side fluid population window 15, the heat transfer tube bundle 11, the primary side fluid outlet window 16, etc., or if it is larger than t, then the upper Room 1
9 from flowing into the lower chamber 20. Therefore minutes^1
By removing one plate, wetting of each part of the heat exchanger
The occurrence of excessive thermal stress due to the difference in expansion/contraction m caused by the change is prevented, and furthermore, by setting the labyrinth seal, it is possible to provide a heat exchanger that prevents dissociation of the -C primary side fluid.

[Other Embodiments of the Invention] The present invention is not limited to the embodiments described above, and the number of grooves in the disc can be increased or decreased as appropriate, as shown in the cross-sectional view of FIG. 4, and various shapes can be taken as shown in the cross-sectional view of FIG. Of course, it is also possible to provide the sea urchin groove in the opposite direction along the length 1, as shown in the cross-sectional view of FIG.

On the other hand, it is of course possible to use a heat exchanger in which the primary fluid flow path and the secondary fluid flow path are completely replaced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional heat exchanger, and FIG. 2 is a sectional view of a conventional heat exchanger. 1 is a partial Wi-side view showing an enlarged labyrinth seal forming portion according to the present invention, and FIGS. 3 to 5 are partial cross-sectional views showing other embodiments according to the present invention. 1...Outer shell, 2...Primary side fluid 8 [1 nozzle, 3
...Primary side fluid outlet nozzle, 4...Outer shroud, 5...Inner shroud,
6... Descending pipe, 7... Bellows, 8... Secondary side fluid outlet nozzle, 9... Secondary side upper head plate, 10... Upper color plate, 11
...Heat transfer tube bundle, 12...Lower plenum, 13...
・Lower tube plate, 14... Division plate, 15... Primary side fluid inlet window, 1G... Primary side fluid outlet lT1 window, 17.
... Disc (1), 18... Disc <2), 19...
Upper office, 20...Lower office agent: Patent attorney Norichika Kensuke (and one other person) Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] High-temperature 1
In a shell-and-tube heat exchanger that exchanges heat between the downstream fluid and the low-temperature secondary fluid, it can be placed at any position where the fluid before heat exchange and the fluid after heat exchange can be separated. , a disc with several grooves in the radial direction or longitudinal direction from the outer shell, and an external shroud disposed inside the outer shell so as to cover the disc. A heat exchanger characterized by a structure that forms a lahyrinth seal with a disc that increases the bulk.