JPS6337228A - Leak tester of multitube type heat exchanger - Google Patents

Abstract

PURPOSE:To inspect the welded part in other housing in parallel to a leak test, by a method wherein one end of a header is connected to a partition tube plate to provide an air chamber so as to surround the root parts of heat transfer tubes. CONSTITUTION:Both ends of a housing 10 are closed by semispherical mirror plates 11a, 11b and a header 12 is arranged in the housing 10 in opposed relation to one of the mirror plates and both opening parts of each of U-shaped heat transfer tubes 13 are arranged to communicate with the header 12. An air chamber 20 is provided so as to surround the root parts of the tubes 13 and constituted of a testing body 21 extending by a definite distance in the extending direction of the heat transfer tubes 13 from the back surface of a tube plate 8 and a partition plate 22 closing the other end of said body 21. When high pressure air is sent into the air chamber 20 from the outside of the housing 10 through a pipe 5 and an air port 23, air fills the air chamber 20. When a flaw is present at a tube expanding part or a seal welded part 9, air is leaked to the inside of the header 12. Therefore, an inspector can observe this leakage of air inside the header 12 to make it possible to determine a leak point.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a seal between a heat transfer tube and a tube plate of a multi-tube heat exchanger built in a housing closed with end plates at both ends. This invention relates to a leak test device used to inspect defects in welds, etc.

(Prior Art) Generally, in a shell-and-tube heat exchanger, heat transfer tubes and tube sheets are assembled using a welding process called tube expansion and seal welding, which has the highest airtightness. In this case, the shell-and-tube heat exchanger must be airtight at the tube expansion section and seal welding section.
In order to check whether there are any problems under the pressure conditions during use, leakage tests are conducted after assembly and during periodic inspections in an effort to discover defects.

As shown in FIG. 6, the conventional method for this inspection is to close one port of the heat exchanger tube 1 with a plug 2, insert an air nozzle 3 into the other port, and supply air from an air source 4 to the air supply pipe 5.
A method in which the supply source valve 6 is closed when the internal pressure reaches a certain value, this state is maintained for a certain period of time, and the emptying of the pressure drop 7 is checked: There is a known method of estimating the existence of a leak point if there is a pressure drop. In addition, the code 8 in the figure is a tube plate, and the code 91j1
Each seal weld is shown.

-・In contrast to the above heat exchanger tube 1, which is constructed on a straight line, a heat exchanger tube formed in a U-shape (IIi) is used, and headers [!] are used at both ends of the heat exchanger tube. FIG. 7 shows how to conduct a leakage test for this type of device (see Japanese Patent Laid-Open No. 178197/1983).

1 - In Fig. 7, the reference numeral 10 connects both ends to the chain plate 11.
A and 11b show a closed housing, and a header 12 is installed inside this housing 10, and this header t! Connect the double-opened [] part of the heat exchanger tube 13 to 12! It has a built-in shell-and-tube heat exchanger. In this leakage test for the shell-and-tube heat exchanger, air guided from the air supply pipe 5 is fed through the medium port 14 provided at the bottom of the nosing 10 to pressurize the inside of the housing 10 to every corner. -Bufu, Kanyose-t! The inspection port passes through the connector 17 that connects the manhole 15 of No. 12 and the manhole 16 of the housing 11. 11, and inspect the presence or absence of leakage by approaching the seal welded part - 46°. Note that reference numeral 181-1. Heating medium person ``1, numeral 19 indicates heating medium 11 sweat'' respectively.

(Problem to be solved by the invention) As mentioned above, in the leakage test of multi-tube heat exchangers, heat exchanger tubes
The seal weld 9 between the heat exchanger tube 1 and the tube plate 8 should be inspected with more emphasis than other parts.The method shown in FIG. 6 cannot inspect leakage due to damage to the heat exchanger tube 1 itself. However, since it is not possible to apply pressure to the tube expansion part and the seal weld part 9, a satisfactory inspection cannot be performed. Further, since this method can only inspect one heat transfer tube 1 at a time, the work efficiency is extremely poor, and there is a problem that the inspection time is particularly long when applied to a multi-tube heat exchanger for a doll.

On the other hand, with the method shown in FIG. 7, it is also possible to inspect the expanded tube parts 1 and 11 and the seal welded part 9, and all the heat exchanger tubes 12 can be inspected in one inspection, etc. It is thought that the above problems have been almost completely resolved. However, this method (Mahousing 10
It is necessary to apply 110 pressure to the entire inside of the housing 10, and while the heat exchanger tube 12 is not being tested for leakage, it is impossible to inspect other welds in the housing 10. This poses a problem when trying to shorten the inspection time for the entire device. For example, in nuclear power generation plan 1-, all key welded parts are inspected during periodic inspections, or there are many inspections inside the housing 10, and if it is not possible to enter inside for the above reasons, several locations will be inspected. Methods such as parallel testing will no longer be available.

Therefore, the purpose of the present invention is to provide a multi-tubular heat exchanger that is capable of inspecting welded parts in other housings in parallel with the leakage test when performing a leak test on a multi-tubular heat exchanger built into a housing. An object of the present invention is to provide a leakage test device for a heat exchanger.

[Structure of the Invention] (Means for Solving the Problems) The leakage test device according to the present invention has an air chamber connected to a tube plate that partitions one end of the header and surrounding the root portion of the heat transfer tube (J
This is a special event.

(Function) When carrying out a leakage test on a shell-and-tube heat exchanger, the expansion section and seal weld section of the heat transfer tube are the most important objects of inspection. In other words, if the base of the heat exchanger tube is inspected at the midpoint, it can be said that most of the leakage tests are completed. The present invention is provided with an air chamber that surrounds the entire root portion of the heat exchanger tube, and during a leakage test, air is sent into this air chamber from the outside to keep the 11 tube parts of the heat exchanger tube and the seal melt 1 constant. It is possible to apply pressure. If there is any defect in the header, the leaked air will blow out inside the header on the opposite side, and the inspector will observe the flow of air inside the header. By doing this, you can see where the leak is.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 2.

In FIG. 7, τ:r+=1o indicates a housing, and both ends of this housing 100 have hemispherical mirror plates 11a.
, 11b. Also, inside the housing 10, a pipe head 12 is arranged opposite to one of the end plates, and this pipe head I! 12 and the double-opened 1-] portions of the single-shaped heat exchanger tubes 13 are arranged so as to communicate with each other.

On the other hand, in the present invention, the air chamber 20 is arranged so as to surround the root portion of the heat exchanger tube 13. This air chamber 20131 consists of a test body 21 extending a certain distance from the back surface of the tube plate 8 in the direction in which the heat transfer tubes 13 are extended, and a partition plate 22 that closes the other end of this test case 111ii121. The air chamber 20 is a room that is required to be completely airtight, especially the part where the heat transfer tube 13 penetrates the cut plate 22 (', 1, as shown in FIG. Using V4, the pipe is expanded and fixed where it comes into close contact with the circulation hole of the partition plate 22.

In addition, in the figure, the sign 23 indicates air [ ] used as a means of communication between the air chamber 20 and the outside.

In the case of the large combination described in 1 above, when performing a leakage test on the expanded portion and seal welded portion 9 of the heat exchanger tube 13 and tube plate 8, high pressure is of air (for example, around 3atj1) is sent into the air chamber 20. This air fills the air chamber 20, and pressure is applied to the tube expansion part and the seal weld part 9, and if there is any defect there,
[Air leakage inside the pipe head] 10. Inspector 15L tube! By observing this air leakage inside the tube 12, it is possible to determine the leakage location.

According to the present invention, all the expanded pipe parts and seal weld parts 9 that are subject to leakage testing can be completed in one inspection, and there is no need to send high-pressure air into the inside of the housing 10. Therefore, inspections of other welds can be carried out in parallel with the leakage test, which is very helpful in shortening the inspection time for the entire multi-tube heat exchanger. Furthermore, the present invention, which feeds air into the air chamber 20 with a small volume, is different from the conventional housing co.
Compared to the method of sending air to every corner of the room, the amount of air required is less than 1,710 yen, making it economical.

Next, an embodiment of the present invention will be explained with reference to FIGS. 3-5.

FIG. 3 is an enlarged view of section a in FIG. 1, and shows the air chamber 20.
In order to improve airtightness, a groove 25 is bored in the exit hole of the partition plate 240, and an O-ring 26 is installed in this groove 25. FIG. 4 is an enlarged view of part a in FIG. By using the method of expanding the tube as shown, the air chamber 20
It is possible to make the airtightness M- higher.

On the other hand, FIG. 5 shows an example in which a communication hole 30 is bored in the tube plate 29 as a communication means between the air chamber 20 and the outside. In this case, a series of operations associated with the leakage test can all be performed inside the pipe 12, making it possible to proceed with the inspection more efficiently.

[Effects of the invention in the Song Dynasty] As stated above, the present invention is excellent! Since an air chamber is provided that surrounds the base of the heat exchanger tube and is connected to the tube plate that partitions one end, the expansion part A3 of all τ and the seal weld part, which are subject to the leakage test, can be inspected in one inspection. Moreover, since there is no need to send high-pressure air into the housing, inspections of other welds can be performed in parallel with the leakage test.

According to the present invention, the entire shell-and-tube heat exchanger can be inspected at 0. This has the excellent effect of shortening the space between 'f'.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a leak test device for a multi-tubular heat exchanger according to the present invention, Fig. 2 is an enlarged cross-sectional view of the seal portion of the air chamber, and Figs. 131 is a sectional view showing another embodiment of the invention; FIG. 5 is a sectional view showing a slightly different embodiment of the invention; FIGS. 6 and 7 are cross-sectional views showing a conventional leak test device. It is a diagram. 8......Pipe Plate 9...Seal welded part 10...Housing 11 all l b...[Plate 12...] ..... Header I 13 ..... Heat exchanger tube 20 ..... Air chamber 21 ..... Test cylinder 22.24.27. 29...Partition plate 23...Air port 25...Groove 26...O-ring 2B...・Sealant 30... Communication hole applicant Toshiba Corporation Agent Patent attorney Suyama Ino 1- Procedural amendment (voluntary) 1986. January 21st, 1, Display of the case: Japanese Patent Application No. 180506/1986 2, Title of the invention: Leak test device for multi-tube heat exchanger 3, Person making the amendment: Relationship with the case/Patent applicant: Yukiyuki, Yozaki City, Kanagawa Prefecture 72 Horiyo-cho (307) Toshiba Corporation 4, Agent 2-1 Kanda Tamachi, Chiyoda-ku, Tokyo 101 Column 6 for detailed explanation of the invention specified, Contents of amendment (1) Page 4 In the second line from the bottom, correct [house E'''F*>J as "mirror plate 11a" ζ(・1.t(+, /2(,
, 11 ・Pa (2) Correct "Heat transfer tube 12" in the 7th line from the top of the 5th line, the 2nd line from the top of the same page, and the 3rd line from the top of the 6th line to ``1 Heat transfer tube 13''. (3) Correct ``Figure 7'' in the second line from the bottom of the 7th line to ``Figure 1''. (4) On page 7, line 10, ``Seal weld'' is corrected to ``1 seal weld.''(5> On page 9, line 11, "Completion" is corrected to "End".

Claims (7)

[Claims] (1) A multi-tubular heat exchanger built in a cylindrical housing whose both ends are closed by a pair of end plates, the openings of a large number of heat transfer tubes extending along the longitudinal direction of the housing. In a multi-tubular heat exchanger in which a connecting header is arranged opposite to one of the end plates, an air chamber is arranged so as to overlap the tube plate that partitions one end of the header and surround the root portion of the heat exchanger tube. A multi-tubular heat exchanger, characterized in that a constant pressure is applied to the expanded portion, seal welded portion, etc. of the heat transfer tube by feeding air into the air chamber from the outside during a leakage test. Leak test equipment. (2) The air chamber is comprised of a test shell connected to a tube plate and a partition plate that closes the other end of the test shell. Leak test equipment for tubular heat exchangers. (3) The heat exchanger tube is expanded at the part where it passes through the partition plate, so that the heat exchanger tube is brought into close contact with the through hole of the partition plate to maintain airtightness of the air chamber. Leak test equipment for shell-and-tube heat exchangers as described in Section 3. (4) Leakage in the multi-tubular heat exchanger according to claim 2, characterized in that an O-ring is attached to the portion where the heat transfer tube passes through the partition plate to maintain airtightness of the air chamber. Test equipment. (5) Leakage in the multi-tubular heat exchanger according to claim 2, characterized in that a sealing agent is applied to the portion where the heat transfer tube penetrates the partition plate to maintain the airtightness of the air chamber. Test equipment. (6) The leak test device for a multi-tubular heat exchanger as set forth in claim 2, characterized in that the test shell is provided with an air port that communicates the air chamber with the outside. (7) The leak test device for a multi-tubular heat exchanger as set forth in claim 2, wherein a communication hole connecting the air chamber to the outside is provided in the tube plate.