JPH0417356B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a retainer at both ends of a tube of a heat exchanger, and cleans the inside of the tube by moving a cleaning material such as a brush. The present invention relates to a tube cleaning device for a heat exchanger that cleans the inner wall of the tube by reciprocating the cleaning material while changing the direction between the forward and reverse directions as needed using a valve provided at the entrance and exit of the heat exchanger.

Note that in this specification, the term "strainer" includes so-called strainers, strainers, filters, and the like.

[Prior art]

A conventional example of this type of tube cleaning device is shown.

For example, as shown in FIG. 7, the tubes 3 of the heat exchanger 1 are attached to the tube plate 2 by a method such as tube expansion. There are water chambers 4 at both ends of the heat exchanger, and the fluid flows into the water chambers 4, passes through the tubes 3, and exits from the opposite chamber. A basket-shaped container 5 is attached to each end of the tube as a holder by a holding plate 7, and a tube cleaning material 6 is stored in the container 5. In FIG. 7, since the flow direction of the fluid in the tube is to the right as viewed from the drawing, the cleaning material 6 is stored in the right container 5. Also, the flow flows from the left side to the right side in the figure, from the tube 3 to the storage container 5, and from the small hole 51 of the storage container to the water chamber 4 on the right side.
leaks inside. The left water chamber is not shown.

A valve is connected to the inlet and outlet of the heat exchanger water chamber 4, and the flow direction is changed by switching the valve. For example, as shown in FIG. 8, four valves 31, 32, 33, 3 are installed at the inlet and outlet nozzles of the heat exchanger water chamber
A valve pipe 30 consisting of 4 is provided. In FIG. 8, the white valves 31 and 33 are shown in an open state, and the black valves 32 and 34 are shown in a closed state. By switching the opening and closing of each valve of this valve piping 30 in the opposite direction, the direction of the flow supplied from the pump 35 changes from a solid line to a broken line, and the cleaning material 6
(See FIG. 7) leaves the container 5, flows while cleaning the inner wall of the tube, and is retained in a container attached to the opposite end of the tube.

[Problem that the invention seeks to solve]

The purpose of the tube cleaning device is to keep the tubes of the heat exchanger clean at all times and to eliminate the need for regular manual maintenance such as tube cleaning. However, this type of tube cleaning device is sensitive to fluids containing filamentous foreign matter, and if filamentous foreign matter such as hair or fibers enters the fluid,
The cleaning material 6 becomes tangled in the storage container 5 and becomes clogged within the storage container 5, making it inoperable, resulting in the disadvantage that maintenance must be performed quite frequently.

Therefore, when using fluid containing such foreign substances, this type of tube cleaning device cannot be used.

FIG. 10 shows another conventional example, in which a filtration device 3 using sand or the like is installed between the switching valve 39 and the heat exchanger 1.
7 and 38 to prevent almost any foreign matter from entering the heat exchanger 1, and compared to the system shown in FIG. 8, it can operate without maintenance for a long period of time. However, in this method,
If small foreign matter aggregates and becomes large after passing through the filter devices 37 and 38, it will no longer be able to exit from the heat exchanger 1 side to the switching valve 39 side. Further, even if algae grows inside the heat exchanger 1 after long-term use, the algae will not be able to come out from the heat exchanger 1 side to the switching valve 39 side. As a result, the filtration device 3 is placed across the heat exchanger 1.
Foreign matter moves back and forth between 7 and 38, and if the accumulated amount increases over a long period of time, it will become impossible to operate.

In addition, if oil is contained in the fluid, the oil may aggregate in the heat exchanger 1 and become ball-shaped, which may cause the heat exchanger 1 to become inoperable.

The present invention solves the above problems, and even if a fluid containing foreign substances such as filamentous foreign matter or oil is used, the cleaning material does not become inoperable, and the inside of the tube can always be kept clean. It is also an object of the present invention to provide a tube cleaning device for a heat exchanger that can always keep a filter clean.

[Means for solving problems]

The present invention provides a heat exchanger having a water chamber and a tube, with a tube cleaning material holder provided at both ends of the tube, the tube holding the cleaning material, and connected to the inlet/outlet of the water chamber so that the inlet flow A tube cleaning device that cleans the inner wall of the tube by providing a valve for switching the flow path between the flow path and the outlet flow path, and reciprocating the cleaning material within the tube using the flow of internal fluid accompanying the switching of the flow path. A strainer is provided between the switching valve and the inlet flow path of the heat exchanger, and between the switching valve and the outlet flow path of the heat exchanger. At least one of the strainers has a one-way strainer that has a strainer effect on the flow toward the heat exchanger, but allows free passage of the flow in the opposite direction and has no strainer effect. This tube cleaning device is characterized by:

In FIG. 1, a strainer 40 is provided as a strainer in an inlet passage 42 between a four-way switching valve 39 and the water chamber 4 of the heat exchanger 1. Outlet channel 4 between water chamber 4'
3 is provided with a one-way strainer 41 as a strainer.

When the fluid flows backward by operating the switching valve 39, the inlet and outlet of the fluid are switched, but in this specification, in order to distinguish between these two inlet and outlet channels, one of them will be referred to as an "inlet channel". and the other one is called the "outlet channel."

The one-way strainer 41 has a cylindrical punched metal plate with one end open inside the casing 44.
A strainer cylinder 45 made of a mesh or the like is provided, and an opening/closing lid 46 is provided at the open end of the strainer cylinder 45, and the opening/closing lid 46 is automatically closed by the flow toward the heat exchanger 1 from the switching valve 39. The flow passes through the strainer tube 45 and has a strainer effect, but for the opposite flow, an opening/closing lid 46 is automatically opened by the flow to allow free passage and prevent the strainer from acting.

The switching valve 39 is now in the state shown by the solid line,
When fluid is supplied from the supply path 47, the fluid first passes through the filtration device 40 in the inlet flow path 42, where it passes through foreign matter and becomes clean, enters the water chamber 4, and enters the heat exchanger 1. The heat exchanger fluid flows from the water chamber 4' to the outlet channel 43.
This leads to the one-way strainer 41. The one-way strainer 41 is reached. Since the one-way strainer 41 allows this flow to pass freely, the fluid passes through the switching valve 39 and is discharged from the discharge passage 48 as it is.

In this case, the foreign matter that has passed through the filtration device 40 or that has already remained in the heat exchanger 1 or the inlet flow path 42 or the outlet flow path 43 is discharged without being obstructed by the one-way strainer 41 due to the above flow. Ru.

Most of the foreign matter in the fluid supplied from the supply path 47 is blocked by the switching valve 39 side of the filter device 40.

Next, when the switching valve 39 is switched to reverse the flow path, the opening/closing lid 46 is closed and the one-way strainer 41 functions as a strainer, thereby blocking most of the foreign matter in the fluid. The fluid that has entered the heat exchanger 1 enters the filter device 40 through the inlet flow path 42, pushes back the foreign matter that was blocked on the switching valve 39 side of the filter device 40, and discharges it through the switching valve 39.

At this time, the foreign matter separated in the heat exchanger 1 is blocked by the heat exchanger 1 side of the filtering device 40.

Next, when the switching valve 39 is operated again to change the direction of the flow path, the foreign matter that was blocked on the heat exchanger 1 side of the filter device 40 is pushed back and reaches the outlet flow path 43 via the heat exchanger 1. It is discharged through the switching valve 39 without being blocked by the one-way strainer 41.

As the switching valve 39, a plurality of valves or a three-way valve may be used instead of the four-way valve.

FIG. 2 shows another embodiment of the one-way strainer 41, in which the strainer cylinder 45 is a non-perforated plate and the opening/closing lid 4
6 is made of punched metal.

FIG. 3 shows another embodiment of the one-way strainer 41, in which a strainer cylinder 45 made of a non-perforated plate has holes 4 in the middle.
9 and is slidably provided with an inner cylinder 52 having a punching metal 50 on the end face,
Inner cylinder 52 for flow from left to right in the figure.
extends and the flow flows freely from the hole 49, but the inner cylinder 52 is pushed in against the flow from right to left.
The hole 49 is hidden and the punched metal 50 acts as a strainer.

If the flow direction of heat exchange is determined, the switching valve 39 is normally turned back on within a few minutes.

Figure 4 shows another example in which the flow direction is not determined, such as when there is not much difference in heat transfer performance no matter which nozzle becomes the inlet. The switching valve 39 is switched between the two channels, and one-way strainers 41 are used in both channels.

FIG. 5 shows another embodiment, in which one-way strainers 53 and 54 are electrically operated valves. When the flow is changed, the strainer is sufficiently backwashed to wash away most of the foreign matter, and then it is opened to flush away the foreign matter that came from the heat exchanger 1 side, and the timing of opening and closing can be freely adjusted. It has been made possible. The shape of the valve is a butterfly valve, and the valve plate is made of a perforated plate such as punched metal.

FIG. 6 shows another embodiment in which a mesh portion 56 of a strainer 55 is cleaned with a brush 57.
It is effective to automate the brush 57 as an electric motor and automatically perform cleaning during backwashing.

〔Effect of the invention〕

The present invention provides a strainer between a switching valve and an inlet channel of the heat exchanger, and a strainer between a switching valve and an outlet channel of the heat exchanger. At least one of the strainers has a strainer effect on the flow toward the heat exchanger, but a one-way strainer that allows free passage and does not have a strainer effect on the flow in the opposite direction is interposed. As a result, even if the fluid flow direction is changed and the cleaning material is moved back and forth within the tube, the filamentous foreign matter that tries to flow in will be captured by the filter, and the foreign matter will become entangled with the cleaning material and the retainer, making cleaning impossible. It is safe to use and easy to handle, and one strainer can be cleaned at all times, so the tube cleaning function can be fully demonstrated, and there is no residual accumulation of foreign matter inside the heat exchanger, making it easy to use. Since it can be removed from the system, the flow path surrounding the heat transfer pipe is always used in good condition, there is no clogging of the cleaning body, and even fluids containing foreign substances can be easily used, and maintenance is also extremely easy. .

[Brief explanation of drawings]

FIG. 1 is a flow diagram of an embodiment of the present invention, FIG.
FIG. 3 is an explanatory diagram of an embodiment of a one-way strainer, and FIGS. 4, 5, and 6 are flow diagrams of another embodiment.
Figure 7 is an enlarged cross-sectional view of the main parts of a conventional heat exchanger;
9 is a sectional view of the vicinity of the container of the conventional example, and FIG. 10 is a flow diagram of the conventional example. 1... Heat exchanger, 2... Tube plate, 3... Tube, 4, 4'... Water chamber, 5... Storage container, 6... Cleaning material, 7... Holding plate, 30... Valve piping ,3
1, 32, 33, 34... Valve, 35... Pump, 37, 38... Passing device, 39... Switching valve,
40... strainer, 41... one-way strainer,
42... Inlet channel, 43... Outlet channel, 44...
Casing, 45... Strainer cylinder, 46... Opening/closing lid, 47... Supply channel, 48... Discharge channel, 49
... hole, 50 ... punching metal, 51 ... small hole, 52 ... inner cylinder, 53, 54 ... one-way strainer, 55 ... strainer, 56 ... mesh section, 57 ... brush.

Claims (1)

[Claims] 1. A heat exchanger having a water chamber and a tube, with a holder for tube cleaning material provided at both ends of the tube, holding the cleaning material in the tube, and connecting it to an entrance/exit of the water chamber. A valve is provided to switch the flow path between the inlet flow path and the outlet flow path, and the cleaning material is reciprocated within the tube using the flow of internal fluid accompanying the switching of the flow path to clean the inner wall of the tube. In the tube cleaning device, strainers are provided between the switching valve and the inlet channel of the heat exchanger, and further between the switching valve and the outlet channel of the heat exchanger, and strainers are provided between the switching valve and the outlet channel of the heat exchanger. At least one of the strainers has a strainer action for the flow toward the heat exchanger, but a one-way strainer that allows free passage and does not have a strainer action for the flow in the opposite direction is interposed. A tube cleaning device characterized by its deployment.