JPS63180084A - Shell and plate type heat exchanger - Google Patents

Abstract

PURPOSE:To secure positive sealing and to facilitate management for leakage by connecting annular spaces between large and small annular gaskets loaded around the peripheries of through holes connecting closed passages for introducing and leading out a fluid within the closed passage, with each other through small holes. CONSTITUTION:Heat transfer elements 4 form closed passages A and opened passages B alternately. The closed passage A communicate with each other via through holes formed in a plate 10. Around the peripheries of through holes 6, concentric circle shaped gasket grooves 12 and 14 exist annular gaskets 16 and 18 are loaded therein, to conduct double sealing between the external part and passages A. Annular spaces 20 between the gaskets 16 and 18 all communicate with each other through small holes 22. the spaces 20 can arrest a fluid leaking from gasket 16 and 18 to analyze and measure the concentration of the fluid. By these procedures, a positive sealing effect can be obtained and existence of the leakage of the fluid and the degree of the leakage can be easily checked.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a shell-and-plate heat exchanger, and more particularly to a seal structure in a shell-and-plate heat exchanger.

A conventional Ω-strain shell-and-plate heat exchanger is a type of plate heat exchanger in which heat exchange is performed indirectly between two fluids flowing in adjacent passages through a partition wall. ,
As shown in FIG. 3, a plurality of plates (4) serving as heat transfer elements are housed in a shell (2) in a stratified state. Passages (A) open to the inner space of the shell (2) and passages (B) open to the interior space of the shell (2) are alternately formed. One of the fluids mediating heat exchange (a) is supplied to the passages (A) between them, and the other fluid (b) is once supplied to the internal space of the shell (2), and then from there. into each open passageway (B).

An example of a shell-and-plate heat exchanger is JP-A-55-
It is described in Japanese Patent No. 102892. This known shell-and-plate heat exchanger prevents leakage of fluid around a through hole (6) (6°) for introducing fluid into or removing fluid from a closed channel (A). In order to prevent this, a seal is provided by an annular O-ring gasket (8) (8") made of an elastic material such as synthetic rubber that surrounds and extends the through hole (6) (6").

In the above seal structure, gaskets made of elastic materials such as synthetic rubber have particularly poor gas sealing properties, so a satisfactory sealing effect cannot be expected, and even if leakage occurs, Since it is not easy to detect this, once leakage occurs, problems such as mixing of the reheat exchange fluids are allowed to progress. In other words, conventionally no measures have been taken to constantly check for leaks.

The purpose of this invention is to solve the above-mentioned problems in shell-and-plate heat exchangers,
That is, the present invention aims to provide a seal structure that more actively prevents leakage and can easily manage leakage.

・In order to

This invention provides a shell-and-plate heat exchanger in which a pair of large and small annular holes are formed around a through hole that connects the closed passages to each other in order to introduce a fluid into the closed passage or lead out the fluid from the passage. The gasket is attached to form a double seal, and the annular space formed between these gaskets is made to communicate with each other through a small hole bored in the plate.

The closed passage is doubly sealed by a pair of large and small gaskets. In other words, an annular cavity defined by two gaskets is interposed between the closed passage and the outside (inner space of the shell), so as to eliminate as much as possible the mixing of the two fluids that should mediate heat exchange. act.

Next, embodiments of the present invention will be described with reference to the drawings. Note that members or parts in the middle of the drawings are designated by the same reference numerals.

Figure 1 shows two adjacent heat transfer elements (4) (4)
, and each heat transfer element (4) has an open passage (B) formed between the heat transfer elements.
A pair of plates (10) (10'') are hermetically joined together along their peripheries by welding or other appropriate means to form a passage (A) inside that is closed to the outside.
Closed passages (A) and open passages (B) are formed alternately.

Closed passage (A) is play) (10) (10°)
They communicate with each other through a through hole (6) bored in the. All through holes (6) are arranged in a straight line and communicate with the supply opening provided in the shell at one end (see Figure 3). two gaskets a (12
) (14), each of which is fitted with annular gaskets (16) and (18). These gaskets (16) and (18) provide a double seal between the passage (A) and the outside and thus also the passage (B).

There is an annular cavity (
20)・ is formed and this void is played) (10)(
They all communicate through small holes (22) drilled at an angle of 10°. The cavity (20) can be used to capture fluid leaking from the gaskets (16) and (18) and discharge it to the outside of the vessel. Furthermore, if either or both of the fluids in the passages (A) and (B) are gas, the cavity (2
By analyzing and measuring the concentration of the gas sucked from 0), the presence and extent of leakage can be checked.

Alternatively, if the cavity (20) is filled with liquid, leakage can be more actively prevented. That is, by pressurizing and sealing the liquid, the pressure difference with, for example, the fluid in the passageway (A) becomes small, so that the leakage rate can be suppressed to a low level.

Furthermore, by pressurizing the fluid to a higher pressure than the fluid in the passageway (A), leakage can be completely eliminated. in this case,
The liquid filling the cavity (20) must be selected to be harmless to the heat exchange fluid. Furthermore,
A space (20) is provided so that the liquid level of the filled liquid can be monitored externally.
By simply connecting a transparent tube such as glass or attaching a sight glass or liquid level gauge to the tank, you can check the amount of leakage from changes in the liquid level. Therefore, even if a leak occurs due to a decrease in the airtightness of the gasket, it can be easily detected and appropriate measures can be taken immediately.
This avoids situations such as mixing of heat exchange fluids.

Note that since FIGS. 1 and 2 only partially show the upper part of the heat transfer element (4), there is no other way to guide the fluid that has passed through the passage (A) to the outlet provided in the shell. Although one of the through holes (6') is not shown in the drawing, as far as the sealing structure is concerned, there is no difference from the case of the through hole (6) described above.

According to this invention, a reliable sealing effect can be obtained, and leakage control can be easily and inexpensively carried out, so it is especially useful for shell and plates that handle gases that ordinary gaskets are not good at. Type heat exchangers play an important role in practical use.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a heat transfer element showing an embodiment of the present invention, Fig. 2 is a front view of the heat transfer element shown in Fig. 1, and Fig. 3 is a schematic cross-sectional view of a conventional shell-and-plate heat exchanger. be. (A) - Closed passage, (B) - Open passage, (2
) −・she) I/, (4>・〜・heat transfer element, (
6) (6') -m-through hole, (10) (1
0') - play 1, (16) (18) - gasket, (20) - void, (22) - small hole. Expansion Xt is shown in Figure 1 Figure 2

Claims (2)

[Claims] (1) Consisting of a group of stratified plates that alternately form closed passages and open passages with respect to the shell internal space, and a shell that accommodates the stratified plates, the first fluid is once supplied to the shell internal space. a second fluid is supplied to each open passage and the second fluid is supplied to closed passages which communicate with each other through holes through the plate, so that fluid in adjacent passages is In a device in which heat exchange is performed indirectly between flowing first and second fluids via a plate, the through hole for introducing the fluid into the closed passage or leading the fluid out from the passage. A shell-and-plate heat exchanger characterized in that a pair of large and small annular gaskets is attached around the gasket, and the annular spaces formed between these gaskets are communicated with each other through small holes bored in the plate. (2) The shell-and-plate heat exchanger according to claim (1), wherein the cavity is filled with a third fluid.