JPH0443751Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shell-and-tube heat exchanger having a large number of heat exchanger tubes.

[Conventional technology]

BACKGROUND ART Conventionally, so-called shell-and-tube or multi-tube heat exchangers, in which a large number of heat transfer tubes are fixed to a tube plate and housed in a cylindrical outer shell, have been widely used in various fields.

For example, as shown in FIG. 3, in a conventional heat exchanger 1, both ends of a tube 4 are fixed to tube sheets 2 and 3, and headers 5 and 6 are attached to the tube sheets 2 and 3 by welding, respectively. , an inlet 7 is provided on one header 5 side, and an outlet 8 is provided on the other header 6 side, respectively, and the headers 5 and 6 are partitioned into chambers 9, 11, 10, and 12, respectively. Also,
A cylindrical outer shell 13 is provided around the tube 4, and the outer shell 13 is provided with an inlet 14 and an outlet 15.

The fluid flowing in the pipe enters the chamber 9 of the header 5 through the inlet 7, flows through the pipe 4 into the chamber 10 of the other header, changes direction in the chamber 10, and passes through the pipe 4 to the chamber 11 of the header 5. Then, it passes through the tube 4 and the chamber 12 of the header 6, and is discharged from the outlet 8. On the other hand, the fluid outside the tube flows in through the inlet 14 and exits through the outlet 15, and heat exchange is performed between the fluid flowing inside and outside the tube 4.

In such a conventional structure, headers 5 and 6
are attached to the tube sheets 2 and 3, respectively, but in general, both methods of attachment are permanent, such as welding or brazing, which does not require the header to be removed, or using bolts or other fasteners. Some models are designed to be removable at the flange. (In this specification, the former is a welding type,
(The latter is called a flange type) [The problem that the invention aims to solve] However, since the installation of this conventional welded type is extremely strict, it can be said that there is no leakage of fluid from the attachment part, but it is difficult to remove it and insert it inside the pipe. It is difficult to clean and maintain the pipes, and the inside of the pipes must be cleaned by chemical cleaning. on the other hand,
The flange type is easy to remove and clean, but there is a risk of fluid leaking from the attachment part, so both the welded type and the flange type have advantages and disadvantages.

The main components of absorption refrigerators, water coolers, and heat pumps are all heat exchangers.
A shell and tube type heat exchanger is adopted as the heat exchanger. In the three elements of the condenser, evaporator, and absorber, the fluid flowing inside the pipes is water, and depending on the quality of the water, scale may easily adhere to the inner surface of the pipe over time, and the heat exchange efficiency depends on the performance of the machine. Clean the inside of the pipe frequently, as
It must be kept as clean as possible. For this reason, flange-type headers have traditionally been used, and the inside of the heat transfer tubes has always been cleaned as part of off-season maintenance.

However, the flange type has the risk of water leaking from the attachment part, which has often been a cause for complaints. Therefore, some machines use welded headers and rely on chemical cleaning for cleaning, but chemical cleaning alone is nowhere near as good as the brush cleaning that is done after removing the header on the flange type. Unavoidable disadvantages include a decrease in exchange efficiency, high chemical costs, and undesirable disposal of waste liquid from a pollution standpoint.

The purpose of the present invention is to provide a heat exchanger with a simple configuration and low cost that combines the advantages of the conventional welded type and flange type and can be effectively used in applications where scale is likely to adhere. be.

[Means to solve the problem]

In the present invention, a large number of heat transfer tubes 4 are provided with both ends of each tube fixed to tube sheets 2 and 3, respectively, and headers 5 and 6 are provided on the tube sheets 2 and 3, respectively, so that both headers and a large number of heat transfer tubes are provided. A flow path passing through the heat exchanger tubes is formed, and an outer shell 13 is provided around the heat exchanger tube group to form another flow path outside the heat exchanger tubes 4, and between the fluid inside the heat exchanger tubes and the fluid outside the heat exchanger tubes. In a shell-and-tube heat exchanger 1 that performs heat exchange, an inlet 7 and an outlet 8 for a fluid with the outside are provided together in a header 5 on one side, and the header 5 is permanently attached to the tube plate by a welded portion 5a. A flange portion is formed on the header 6 on the other side, which is attached to the tube plate 2 and has no inlet/outlet for fluid between it and the outside, and the header 6 can be attached to and detached from the tube plate 3 using mounting bolts 6a through this flange portion. This is a heat exchanger characterized in that it is attached.

〔Example〕

FIG. 1 shows an embodiment of the present invention.

In the figure, reference numeral 1 denotes a heat exchanger, in which a heat exchanger tube 4 is fixed at both ends to tube sheets 2 and 3, and headers 5 and 6 are attached to the tube sheets 2 and 3, respectively. header 5
is divided into two rooms, with an entrance 7 and an exit 8.
will be provided. Further, a cylindrical outer shell 13 is provided around the heat transfer tube 4, and the outer shell 13 is provided with an inlet 14 and an outlet 15, and in order to prevent fluid from passing through, the heat transfer tube 4 has a bypass flow. A large number of baffle plates 16 are fitted in such a manner that this occurs.

The fluid then enters one chamber of the header 5 from the inlet 7, is transferred to the other header 6 through the heat exchanger tubes 4, and then enters the other chamber of the header 5 through the heat exchanger tubes 4 again in a circular flow. , discharged from outlet 8.
On the other hand, the fluid outside the tube flows in from the inlet 14, flows in a zigzag shape around the heat transfer tube 4 by the baffle plate 16, and then is discharged from the outlet 15. In this way, heat exchange is performed between the fluid inside and outside the heat exchanger tube 4.

Headers 5 and 6 attached to the tube sheets 2 and 3
Among them, one header 5 is fixedly installed by welding at a welding part 5a, and the other header 6 is fixed by welding at a welding part 5a.
They are each provided by flange attachment at a.

Therefore, when cleaning the inside of the heat transfer tube 4, the header 6 can be easily removed from the tube plate 2 by removing the bolts 6a, and the header 6 can be easily removed from the tube plate 2 by removing the bolt 6a. There is no need to touch it with your hands, and there is no risk of water leakage. and,
By removing the header 6, the inside of the heat exchanger tube 4 can be cleaned with a brush, so the inside of the heat exchanger tube 4 can be cleaned much more cleanly than when using chemicals, and the work requires less effort. Also, the cost is low and maintenance is easy.

Note that in this example, there are two paths, upper and lower, but
The same applies to even numbers larger than that.

Further, since the header 5 on the side having the fluid inlet/outlet, that is, the nozzle side header, is attached by welding and is not touched by hands, there is no fear of fluid leakage.

FIG. 2 shows another embodiment.

In the figure, 20 is a condenser 21, an evaporator 22,
This is a heat exchanger used for an absorption refrigerator in which an absorber 23 is integrally formed.

a nozzle side header 21a equipped with a fluid inlet/outlet;
22a, 23a are gathered on one side (right side in the drawing), and non-nozzle side headers 21b, 22b, 23b, which have no fluid inlet/outlet, are on the opposite side (left side in the drawing)
are collected in.

In this embodiment, the non-nozzle side headers 21b, 22b, and 23b, which have no fluid inlet/outlet, have lids that can be removed separately.
It is attached by flange mounting,
On the other hand, the nozzle side headers 21a, 22a, and 23a having fluid inlets and outlets are permanently attached by welding.

Therefore, when cleaning the inside of the heat exchanger tube 4, use the non-nozzle side header 21b, 2 which does not have a fluid inlet/outlet.
By removing the lids of 2b and 23b, the interior can be easily cleaned, and leakage is prevented by minimizing the flange attachment part that is likely to cause leakage.

[Effect of idea]

The present invention provides a fluid inlet and an outlet together in a header on one side, which is permanently attached to the tubesheet by welding, and a header on the other side with no fluid inlet/outlet to the outside. Forms a flange, and the header is removably attached to the tube plate with mounting bolts through this flange, making the water chamber with the inlet and outlet nozzles permanently sealed, making it a partition. It is possible to prevent leaks from the parts and the outside of the water chamber, reducing leakage by half compared to the all-head flange-mounted type, and compared to the conventional case where the water chambers on both sides are sealed. Since one water chamber without a nozzle is opened, it is extremely easy to clean and maintain the inside of the heat transfer tube, and the other header, to which the supply and drain pipes are not connected, can be removed, so when removing the header, , there is no need to remove the supply and drain pipes, the interior can be easily cleaned without relying on chemical cleaning, stable operation is possible, and reliability can be greatly improved. .

[Brief explanation of the drawing]

Figure 1 is a partially cutaway front view showing an embodiment of the present invention, Figures 2a and b are front and side views showing another embodiment of the present invention, and Figure 3 is a conventional heat exchanger. FIG. DESCRIPTION OF SYMBOLS 1... Heat exchanger, 2, 3... Tube sheet, 4... Heat exchanger tube, 5, 6... Header, 5a... Welded part, 6a...
...Bolt, 7...Inlet, 8...Outlet, 9,10,
11, 12... Chamber, 13... Outer shell, 14... Inlet, 15... Outlet, 16... Baffle plate, 20... Heat exchanger, 21... Condenser, 22... Evaporator, 23
... Absorber, 21a, 22a, 23a... Nozzle side header, 21b, 22b, 23b... Non-nozzle side header.

Claims (1)

[Scope of utility model registration request] A large number of heat exchanger tubes 4 are provided with both ends of each tube fixed to tube sheets 2 and 3, respectively, and headers 5 and 6 are provided on the tube sheets 2 and 3, respectively, to control the flow through both the headers and the large number of heat exchanger tubes. A shell 13 is provided around the group of heat transfer tubes to form another flow path outside the heat transfer tubes 4, and heat exchange is performed between the fluid inside the heat transfer tubes and the fluid outside the heat transfer tubes. In the multi-tubular heat exchanger 1, an inlet 7 and an outlet 8 for fluid between the outside and the outside are provided together in a header 5 on one side, and the header 5 is permanently attached to the tube sheet 2 by a welded part 5a. Further, a flange portion is formed on the header 6 on the other side, which does not have an inlet/outlet for fluid between it and the outside, and the header 6 is removably attached to the tube plate 3 via this flange portion with mounting bolts 6a. A heat exchanger characterized by: