JPS58123094A - Multi-pipe type heat exchanger wherein joint aperture at tube-plate inside surface being blocked, its filler metal and blocking method therefor - Google Patents

Abstract

PURPOSE:To increase the efficiency of a blocking work remarkably, by using an annular filler metal which fully fits to the joint aperture, especially when an aperture between a pipe, which is installed in a reaction tank, and a through- hole is blocked, in a heat exchanger of multi-pipe type. CONSTITUTION:In order to block a necessary number of through-holes 7 with a filler metal 11 being bored through a pipe plate 6, and a joint aperture 11 on the inner side surface of the pipe plate, a pipe 5 thereof being inserted through the hole 7, as annular beveling part 8 is formed previously. On said beveling part 8, a filler metal 10 is fixed in the manner that the whole or a part of said filler metal is burried throughout the front and the rear part of the pipe 5 insertion portion. Then, the pipe plate 6 is heated from its upper or lower surface, fusing the filler metal 10, and the joint aperture 11 at the inner surface of the tube plate 6 between the pipe 5 and the through-hole 7 is blocked, thereby preventing the corrosion of the aperture at the pipe end part.

Description

[Detailed description of the invention] A multi-tubular heat exchanger in which a joint gap between a pipe and a through hole on the inner surface of a tube plate of the multi-tubular heat exchanger to be installed is closed, and
A filler material suitable for that blockage. This article concerns a method for closing the joint gap.

still. In this specification, the inner surface of the tube sheet means the surface of the tube sheet on the body side of the tube sheet.

Conventionally, a multi-tube type was installed in a fermenter to control various types of fermentation.
For heat exchangers, emphasis was placed only on pressure resistance inside the fermenter, and as a result, treatments such as expander treatment and seal welding of the surface of the tube sheet on the tube side were applied to the joints between the tube sheet and the pipes. That was quite sufficient.

However, recent research has revealed the following deficiencies in shell-and-tube heat exchangers. That is, for example, when inserting 120 pipes through a disc-shaped tube plate with a diameter of 832 m+, the pitch of the pipes is 45 mm,
The gap between the pipes has to be narrow, about 20wn, so there is no way to close the small joint gap between the pipe and the through hole on the inner surface of the tube plate, and there is no way to close the gap inside the fermenter. The fermentation liquid had to remain in the above-mentioned joint gap inside the tube plate. In particular, there is a joint gap S at the pipe insertion point on the inner surface of the tube plate, as shown in Figure 1, so the fermentation liquid will enter this small gap, making cleaning work such as cleaning and steam sterilization difficult. However, there was a drawback that the residual liquid remaining in the gap could not be completely removed.

Moreover, in fermentation work, which deals with various types of fermenting bacteria, even a small amount of bacteria can have a serious negative impact on the quality and fermentation time of the next fermented product. There is a need for a shell-and-tube heat exchanger that does not require the effort to completely remove residual germs, or is structurally free from any residual germs.

Furthermore, if bacteria or minute foreign matter enters the joint gap between the tube sheet and the pipe, this becomes a major cause of gap corrosion in the pipe, and there is an urgent need to eliminate these various defects.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and the present invention is directed to a multi-tube heat exchanger that closes the joint gap between the tube sheet and the pipes on the inner surface of the tube sheet, and an abbreviation that is most suitable for this obstruction. Due to the annular filler material and various methods of closing the joint gap, it can withstand use in a fermenter, etc., and does not have a negative effect on the fermented product due to residual bacteria.

Moreover, it is an object of the present invention to provide a multi-tubular heat exchanger, etc., which can prevent pipe crevice corrosion and reduce residual stress caused by welding.

That is, the present invention provides a method for forming the joining gap on the inner surface of the tube sheet between the through hole of a tube sheet in which a required number of through holes are drilled and the pipe inserted into the through hole with a filler metal or without a filler metal. A shell-and-tube heat exchanger, an annular filler material suitable for the plugging, and a method for plugging the same.

Hereinafter, the present invention will be explained in detail based on embodiment figures.

FIG. 2 is a layout diagram showing the mounting positional relationship of the multi-tubular heat exchanger with closed joint gaps on the inner surface of the tube plate according to the present invention, in which (1) is a fermenter (2) is a multi-tubular heat exchanger; It is a heat exchanger. An inlet pipe (8) and an outlet pipe (4) for passing steam or water are fixed to both upper and lower ends of the multi-tubular heat exchanger (2). Alternatively, these pipes may have their inlet and outlet reversed. (5) is a plurality of heat transfer pipes.

Furthermore, a stirring rod α6) is rotatably installed in the fermenter (1), and stirring blades 0η0 of the required number and shape are pivotally attached to the lower part of the stirring rod α6).

Moreover, several multi-tubular heat exchangers (2) are installed in the fermenter (1), and contribute to the stirring effect while also acting as baffles during stirring.

FIGS. 3A and 3B are exploded views showing how the pipe (5) and the like are installed. In the figure, (6) is a tube plate, and the pipe (
It is made of the same material (stainless steel) as 5). In the example, the tube plate (6) has a diameter of 832 mm and a thickness of 25 W.
In IIR, a total of 120 pipes with a diameter of 25 m and a length of 4 m, 15 in the vertical direction and 8 in the horizontal direction, will be planted on this disk. Therefore, the pitch between the pipes is 4
The gap between the 5 mns pipes is as narrow as 20 m+.

FIG. 4 is a sectional view of the first embodiment showing the joint state of the tube sheet (6) and the pipe (5), and (7) is a through hole for the pipe drilled in the tube sheet (6). It is. (8) is an annular groove formed on the inner surface (9) of the through hole (7), and as shown in the partially enlarged view of FIG.
2) is fitted so that all or part of it is buried.

Therefore, the filler metal (2) is
As shown in Figures A and B, it is formed in an annular shape, and its cross-sectional shape can be changed as appropriate, such as a circle, triangle, or square, as a filler material. Further, the filler metal only needs to be approximately annular, and does not necessarily need to be an annular body. Furthermore, the material of the filler material α0) is the same as that of the tube plate (6) and the pipe (5), but it is optimal for a shell-and-tube heat exchanger used in a fermenter or a reaction tank. Depending on the application of the shell-and-tube heat exchanger, solder with a low melting point, a solder alloy such as silver solder, etc. may be used, and in some cases, an adhesive or the like may also be used. 01) is the joining gap between the through hole (7) and the pipe (5).

In addition to the above-mentioned method, as a means of fitting the filler metal 00), as in the second embodiment shown in FIG. (9) may be fitted concentrically with the pipe (5).

In addition, when the filler metal α0) is made of a material with a low melting point, a large number of pipes (5) (5) installed in the tube sheet (6) in advance are used.
・Fit the filler metal (2) aO)... respectively,
If heating is done from the bottom or top (inner side) of the tube plate (6),
Depending on the heating temperature, the tube sheet (
It is possible to close the joining gap (11) between the through hole (7) and the pipe (5) on the inner surface of the pipe (6) with the filler material α0).

FIG. 10 shows a fifth embodiment of the present invention.
In the figure, (denotes a two-sided welding head, <18
) is the moving electrode. In the third embodiment - first, the inner surface (9) of the through hole is concentric with the through hole (7), and
An annular groove α→ having approximately the same wall thickness as that of the pipe (5) to be fixed is formed on the inner side, and then the remaining thick part (2) is formed.
) is melted using a welding machine or the like to close the joining gap 01). In this case, even if the cross-sectional shape of the annular groove 04) is channel-shaped as shown in FIG.
It may be υ-shaped as shown in Figure 2.

Furthermore, in the case of the fourth embodiment shown in FIG. 11, the filler metal αQ
It is also possible to melt the remaining thick part (2) by using a ), the annular four-strip groove (14) remains. In order to avoid the inconvenience of bacteria remaining in the annular groove Q→, the inner surface (9) of the tube plate (6) is previously inserted into the annular groove α→ as shown in FIG. 15 before melting. By cutting the pipe until it is almost flush with the bottom, we are trying to prevent bacteria from remaining at the joints of the pipes and from adhering to them.

However, when the multi-tube heat exchanger is installed in the vertical direction as in the embodiment shown in the second figure, the above-mentioned cutting process on the same plane can be performed only on the inner surface of the lower tube plate. Often, there are cases where it is not necessary to cut the inner surface of the upper tube sheet.

On the other hand, when the multi-tubular heat exchanger is arranged in the left-right direction (the longitudinal direction of the pipes), it is necessary to perform the cutting process on the inner surfaces of both the left and right tube sheets in advance.

FIG. 14 is a cross-sectional view of the tube sheet (6) and pipe (5) after melting the filler acid based on the first embodiment of the present invention shown in FIGS. 4 and 5; , the joining angle between the pipe (5) and the inner surface of the tube sheet (9) is 90°, and the joining gap is 01.
) indicates a completely closed state, and this state is structurally most desirable.

Moreover, FIG. 15 is not shown in FIG. 9 but shows the bonded state after being melted according to the second embodiment. The CI sword is completely closed and has a cross-sectional shape similar to that when welded by so-called fillet welding.

The present invention has the above-mentioned configuration, and includes a multi-tubular heat exchanger mainly used in a fermenter or a reaction tank, with a large number of through holes (γ) bored in the tube sheet thereof and the through holes. The joint gap a force between the pipe (6) inserted in (γ) and the inner surface (9) of the tube plate (6) is closed with the filler metal (10) or without the filler metal α0). As a result, despite conventional cleaning and steam sterilization work, the fermentation target may deteriorate in quality due to the proliferation of bacteria that clog the gaps in the joints, which often occur inside the fermenter (1), etc., and the scheduled production time may be delayed. This makes it possible to completely eliminate inconveniences such as fluctuations.

At the same time, it has become possible to perform actual welding between narrow pipes, making it possible to completely close the joining gap (11) between the tube plate (6) and the pipe (6), thereby preventing corrosion of the gap at the end of the knob. It is now possible to prevent this from occurring, and the service life of the shell-and-tube heat exchanger can be significantly increased.

However, the filler metal α0) used for this closure was not a conventional welding rod, but instead was made into an annular or nearly annular filler material that perfectly matched the welding gap (11), resulting in an increase in work efficiency. We can now expect dramatic improvements and perfect finishing results.

Moreover, in the closing method, an annular groove part (8) is formed in advance on the inner surface (9) of the tube sheet (6), and approximately annular filler metal α pieces are set therein. It is now possible to melt or melt a large amount at the same time, and work efficiency can be significantly improved compared to conventional melting methods.

In addition, in a closing method that does not use filler metal, by forming an annular groove (No. 1), the tube sheet (6) and the pipe (5)
) and the joint gap C11) can be closed with the same material, which is advantageous especially in the case of an atmosphere where the pipe gap is easily corroded, such as in a reaction tank.

As mentioned above, the present invention is capable of fully demonstrating the original functions of multi-tube heat exchangers used in fermenters etc. by welding the back of the tube sheets, and is suitable for the industry. The contributing effects are significant.

[Brief explanation of the drawing]

Fig. 1 is a partial cross-sectional view showing how the tube plate and pipes are attached in a conventional shell-and-tube heat exchanger, and Fig. 2 is a shell-and-tube heat exchanger according to the present invention in which the joint gap on the inner surface of the tube plate is closed. Figure 6A and B are top and side cross-sectional views showing how the tube sheet and pipe are installed, and Figure 4 is the first implementation showing how the tube sheet and pipe are installed. 5 is a partially enlarged view of the same as above, FIGS. 6A, B to 8A, B are a perspective view and a cross-sectional view of the filler metal, respectively, and FIG. 9 is a cross-sectional view of the second embodiment. 10 is a partial sectional view of the third embodiment, FIG. 11 is a partial sectional view of the fourth embodiment, FIG. 12 is a partial sectional view showing the same state after welding, and FIG. 13 14 is a partial sectional view showing the state after welding of the tube sheet inner surface after cutting, FIG. 14 is a partial sectional view showing the state after welding of the first embodiment, and FIG. 15 is a partial sectional view showing the state after welding of the second embodiment. It is a diagram. (1)... Fermenter, (2)... Multi-tube heat exchanger, (3
)...Inlet side pipe, (4)...Discharge side pipe, (
δ)...Heat transfer pipe, (6)...Tube sheet, (γ)...
・Through hole, (8)...Annular groove, (9)...Inner part, Hole...Filler material. 01)...Joining gap, (increase...welding head, θB)
... Moving electrode, 04) ... Annular groove, (b))
... Remaining thick part, α6) ... Stirring rod, aη ... Stirring blade. Patent applicant Fukushima Iron Works Co., Ltd. Figure 6A Figure 6B OL/-10 To Figure 7Figure 7B 71, /l. Figure 8A Figure 8B M”

Claims (6)

[Claims] (1) The joining gap on the inner surface of the tubesheet between the throughholes of the tubesheet with the required number of throughholes and the pipe inserted into the throughholes is closed with or without a filler metal. A multi-tube heat exchanger characterized by: (2) An annular filler material characterized in that it is used to close the joining gap on the inner surface of the tube sheet between the through holes of the tube sheet in which the required number of through holes are bored and the pipe inserted into the through holes. . (3) The annular filler metal according to claim 2, wherein the cross-sectional shape of the filler metal is approximately circular, approximately triangular, or approximately quadrangular. (4) In order to close the joining gap on the inner surface of the tube sheet between the through hole of the tube sheet with the required number of through holes and the pipe inserted into the through hole with filler material, the inner surface of the through hole is used. An annular groove is formed in advance. Then, through the annular groove before or after inserting the pipe,
After a substantially annular filler metal is fitted and set so that all or part of it can be buried in the annular groove, the tubesheet is heated from the upper or lower surface to melt the filler metal, thereby forming a tubesheet. A method for closing a gap in a multi-tubular heat exchanger, characterized in that a gap between a pipe and a through hole on an inner surface is closed. (5) In order to close the joint gap on the inner surface of the tubesheet between the through-holes in the tubesheet with the required number of through-holes and the pipe inserted into the through-holes without using filler metal, first Form an annular concave groove on the side surface that is concentric with the through hole and has approximately the same wall thickness as the pipe to be fixed, leaving the inner gA11 circumference. Cut it so that it is substantially flush with the bottom of the annular groove, or leave it uncut, and then melt the remaining thick part with a welding machine or the like to close the joining gap. A method for closing gaps in a shell-and-tube heat exchanger. (6) In order to close the joint gap on the inner surface of the tubesheet between the through-hole of the tube sheet with the required number of through-holes and the pipe inserted into the through-hole with a filler metal, first An annular concave groove is formed on the side surface, concentric with the through hole, and having a wall thickness approximately the same as the wall thickness of the pipe to be fixed, remaining on the inner layer. is cut so as to be substantially flush with the bottom of the annular groove, or in an uncut state, and an annular filler metal is fitted onto the remaining thick part before or after the pipe is inserted. A method for closing a gap in a multi-tube heat exchanger, characterized in that the gap is closed by melting an annular filler metal.