Strainer Cleaning System

Abstract

To provide a strainer washing system that can surely perform automatic washing, although the system is simply configured.SOLUTION: In normal times, steam flows into a strainer 2 through inlet piping 11 and then flows out into outlet piping 12 through the strainer 2. While, if foreign matters are accumulated in the strainer 2, so that clogging occurs in the strainer 2, inner pressure of the inlet piping 11 rises so that a check valve 4 opens, and steam flows into a heat exchanger 6 so that drain is generated. The generated drain is supplied to the strainer 2, so that the accumulated foreign matters are washed. Then, the inner pressure of the inlet piping 11 rises further, so that a pressure difference between the inner pressure of the inlet piping 11 and inner pressure of the outlet piping 12 increases and therefore a differential pressure regulating valve 8 opens, which ejects the drain and the foreign matters in the strainer 2 at once to the outside through a drain pipe 17 by high-pressure flow.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The strainer cleaning system according to the present application relates to a technique for automatically cleaning a strainer installed in a piping system. [Background technology]

[0002] Strainers have a built-in screen and are installed in piping systems for transporting fluids such as steam to capture foreign matter that gets mixed in with the steam. As a result, foreign matter captured by the screen can accumulate inside the strainer, causing a blockage. If the strainer becomes clogged, it will hinder the transport of the fluid, so it is necessary to clean the strainer and remove the accumulated foreign matter.

[0003] One such technique for cleaning a strainer is a backwashable strainer described in Patent Document 1 below. A strainer body 1 of this strainer is formed with a fluid inlet 2 and a fluid outlet 3, and is provided with a filtering section 4 inside. An inlet pipe 7 is connected to the fluid inlet 2, and an outlet pipe 8 is connected to the fluid outlet 3.

[0004] A branch pipe 9 is connected to the inlet pipe 7, which branches off the inlet pipe 7. A differential pressure valve 6 is connected to the pipe 5 which communicates with the straining section 4. A primary pressure detection pipe 15 of the differential pressure valve 6 is connected to the inlet pipe 7, and a secondary pressure detection pipe 12 is connected to the outlet pipe 8. When the straining section 4 becomes clogged with foreign matter and the fluid pressure in the outlet pipe 8 drops, the differential pressure valve 6 automatically opens. When the differential pressure valve 6 opens, high-pressure cleaning liquid flows from the inlet pipe 14 into the pipe 5, and the foreign matter in the straining section 4 built into the strainer body 1 is automatically washed away. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-169476 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the technology disclosed in the aforementioned Patent Document 1 has the problem that in order to clean the strainer, it is necessary to connect a pipe 5 to a cleaning liquid source and supply high-pressure cleaning liquid, which makes the device configuration complicated.

[0007] In order to solve these problems, the strainer cleaning system according to the present application has an object to provide a strainer cleaning system that can reliably perform automatic cleaning while having a simple configuration. [Means for solving the problem]

[0008] The strainer cleaning system according to the present application comprises: a strainer section that allows a transfer fluid flowing in from a primary piping to pass therethrough and flows out to a secondary piping, and that captures foreign matter mixed in the transfer fluid; a cleaning fluid generating means for generating a cleaning fluid based on the transfer fluid when the internal pressure of the primary side piping reaches a predetermined generation reference pressure, and supplying the cleaning fluid to the strainer portion to clean the strainer portion; The present invention is characterized by comprising: Effect of the Invention

[0009] In the strainer cleaning system of the present application, the cleaning fluid generating means generates cleaning fluid based on the transfer fluid when the internal pressure of the primary side piping reaches a predetermined generation standard pressure, and supplies the cleaning fluid to the strainer section to clean the strainer section.

[0010] In other words, since there is no need to take in cleaning fluid from the outside to clean the strainer portion, automatic cleaning can be performed reliably despite the simple configuration. [Brief description of the drawings]

[0011] [Figure 1] 1 is a block diagram showing a first embodiment of a strainer cleaning system according to the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] [Terminology used in the embodiments] The main terms used in the embodiments correspond to the following elements of the strainer cleaning system according to the present application:

[0013] Strainer 2: Strainer section Check valve 4 and heat exchanger 6...cleaning fluid generating means Heat exchanger 6...Heat exchange section Differential pressure valve 8...Discharge means Inlet piping 11...Primary side piping Outlet piping 12...Secondary side piping Pressure value a1: Reference pressure for generation Pressure difference value a2... Emission standard conditions, Emission standard pressure difference Steam...Transport fluid Drain...cleaning fluid

[0014] [First embodiment] A first embodiment of a strainer cleaning system according to the present application will be described with reference to Fig. 1. The strainer is installed on a pipe and captures foreign matter such as rust and scale (limescale) that is mixed in the fluid flowing through the pipe. In this embodiment, a Y-type strainer with a built-in screen is taken as an example.

[0015] (Description of the configuration of the strainer cleaning system in this embodiment) An inlet pipe 11 and an outlet pipe 12 arranged coaxially are connected to both sides of the strainer 2 , and steam transferred through the inlet pipe 11 passes through the strainer 2 and flows out to the outlet pipe 12 .

[0016] A cylindrical screen (not shown) made of a mesh material is housed inside the screen tube 2a extending below the strainer 2. As the steam passing through the strainer 2 passes through this screen, foreign matter mixed in the steam adheres to the inner periphery of the mesh part of the screen and is captured.

[0017] If foreign matter accumulates on the inner circumference of the strainer 2 and causes clogging of the strainer 2, the transfer of steam from the inlet pipe 11 to the outlet pipe 12 is impeded, and therefore it is necessary to perform cleaning at an appropriate time to remove the foreign matter. For this reason, in this embodiment, a heat exchanger 6 connected to the inlet pipe 11 is provided.

[0018] That is, a branch pipe 13 is branched and connected to the inlet pipe 11, and this branch pipe 13 is connected to the heat exchanger 6. The branch pipe 13 is provided with a check valve 4. The check valve 4 is normally closed, but opens when the internal pressure of the inlet pipe 11 becomes high, and sends steam to the heat exchanger 6 through the branch pipe 13. The check valve 4 is set to open when the value of the internal pressure of the inlet pipe 11 becomes a1.

[0019] The heat exchanger 6 exchanges heat between the steam fed in and the surrounding air, generating condensate from the steam. That is, the steam dissipates heat to the surrounding air inside the heat exchanger 6, and this heat loss changes the steam to generate condensate. The generated condensate flows from the heat exchanger 6 through the condensate supply pipe 14 into the inlet pipe 11 just before the strainer 2, and is supplied to the strainer 2.

[0020] A drain pipe 17 is connected to the tip of the screen pipe 2a of the strainer 2. That is, the inlet piping 11 and the drain pipe 17 are connected through the inside of the screen pipe 2a. A differential pressure valve 8 is installed on this drain pipe 17, and drains (blows) the drain inside the strainer 2 according to the opening and closing of the differential pressure valve 8.

[0021] An inlet pressure detection pipe 15 communicating with the inlet pipe 11, and an outlet pressure detection pipe 16 communicating with the outlet pipe 12 are connected to the differential pressure valve 8. The differential pressure valve 8 opens when the internal pressure of the inlet pipe 11 becomes higher than the internal pressure of the outlet pipe 12, and drains the drain through the drain pipe 17. The differential pressure valve 8 is set to open when the pressure difference between the internal pressure of the inlet pipe 11 and the internal pressure of the outlet pipe 12 becomes higher by a value a2.

[0022] In this embodiment, the pressure difference value a2 at which the differential pressure valve 8 opens is set to be larger than the internal pressure value a1 at which the check valve 4 opens, and the differential pressure valve 8 opens after a predetermined time interval has elapsed since the check valve 4 opened.

[0023] (Description of the operation of the strainer cleaning system in this embodiment) Next, the operation of the strainer cleaning system in this embodiment will be described. First, under normal circumstances, as described above, steam flows into the strainer 2 through the inlet pipe 11, passes through the strainer 2, and flows out to the outlet pipe 12. In this case, the internal pressure of the inlet pipe 11 and the internal pressure of the outlet pipe 12 are almost the same and stable. Therefore, both the check valve 4 and the differential pressure valve 8 are in a closed state.

[0024] If foreign matter accumulates inside the strainer 2 and causes it to become clogged, the amount of steam passing through the strainer 2 will gradually decrease depending on the degree of accumulation of foreign matter, until it reaches a state where no steam can pass through the strainer 2 at all. Because steam continues to be sent to the inlet piping 11 as in normal times, the internal pressure of the inlet piping 11 will gradually increase due to the clogging of the strainer 2.

[0025] Then, when the internal pressure value of the inlet pipe 11 reaches a1, the check valve 4 opens and steam is sent to the heat exchanger 6 through the branch pipe 13. As described above, the differential pressure valve 8 is set to open a certain time interval after the check valve 4 opens, so at this point the differential pressure valve 8 remains closed. As a result of the steam being sent to the heat exchanger 6, drain is generated from this steam.

[0026] The generated drain flows out through drain supply pipe 14 and is supplied to strainer 2. This supplied drain washes away foreign matter accumulated in strainer 2. In this embodiment, as described above, the drain flows into inlet piping 11 immediately before strainer 2. For this reason, the drain supplied to strainer 2 flows into strainer 2 along the same path as the steam that flows in through inlet piping 11 under normal circumstances, so that foreign matter that has been mixed in with the steam and accumulated in strainer 2 can be more reliably washed and removed.

[0027] After the drain is supplied to the strainer 2, the internal pressure of the inlet pipe 11 increases further, and when the internal pressure of the inlet pipe 11 is higher than the internal pressure of the outlet pipe 12 by a value a2 (pressure difference), the differential pressure valve 8 opens. As a result, the drain and foreign matter in the strainer 2 are blown out to the outside through the drain pipe 17 in one go due to the force of the high pressure.

[0028] As a result of the drainage and foreign matter being discharged from the strainer 2 all at once, a flow path through which steam passes is formed within the strainer 2, and steam flows out to the outlet piping 12. As a result, the internal pressure of the inlet piping 11 drops below value a1, and the check valve 4 closes. With the check valve 4 closed, steam no longer flows into the heat exchanger 6, drainage is no longer generated, and the supply of drainage to the strainer 2 is stopped.

[0029] In this way, steam from the inlet pipe 11 passes through the strainer 2 and flows out to the outlet pipe 12, and normal operation is restored. During this process, the pressure difference between the internal pressure of the inlet pipe 11 and the internal pressure of the outlet pipe 12 falls below value a2, which causes the differential pressure valve 8 to close, and thereafter, no steam leakage from the drain pipe 17 occurs.

[0030] [Other embodiments] In the above embodiment, a Y-type strainer is exemplified, but the strainer cleaning system according to the present application can also be applied to other types of strainers, such as a U-type strainer, a T-type strainer, or a piping type strainer.

[0031] In addition, in the above-described embodiment, the check valve 4 and the heat exchanger 6 are exemplified as the cleaning fluid generating means, but other configurations can be used as long as they generate cleaning fluid based on the transferred fluid when the internal pressure of the primary side piping reaches a predetermined generation reference pressure, and supply the cleaning fluid to the strainer portion to clean the strainer portion.

[0032] Furthermore, in the above embodiment, the differential pressure valve 8 that opens when the internal pressure of the inlet pipe 11 becomes higher than the internal pressure of the outlet pipe 12 is exemplified as the discharge means, but other configurations can be adopted as long as they discharge the cleaning fluid in the strainer section when a predetermined discharge standard condition is satisfied. For example, a valve may be used that opens when the internal pressure of the inlet pipe 11 (primary side pipe) reaches a preset value, as this is the discharge standard condition, and discharges the drain (cleaning fluid) from the strainer 2 (strainer section).

[0033] In addition, in the above-described embodiment, a check valve 4 is exemplified as a configuration for allowing steam to flow into the heat exchanger 6, but a valve of another structure may be used as long as it is normally closed and opens when the internal pressure of the inlet pipe 11 (primary side pipe) reaches a predetermined generation standard pressure.

[0034] Furthermore, in the above-described embodiment, an example was shown in which the heat exchanger 6 exchanges heat between the fed steam and the surrounding air to generate drain from the steam. However, cooling water can also be supplied to the heat exchanger 6 to perform heat exchange between the steam and the cooling water, thereby efficiently generating drain.

[0035] In addition, in the above-described embodiment, an example was shown in which the drain generated in the heat exchanger 6 flows into the inlet pipe 11 immediately before the strainer 2, but a configuration in which the generated drain is made to flow directly into the strainer 2 may also be adopted.

[0036] In the above-described embodiment, the check valve 4 is provided in the branch pipe 13 to control the inflow of steam into the heat exchanger 6, and the differential pressure valve 8 is provided in the drain pipe 17 to control the discharge of condensate from the strainer 2. However, a solenoid valve may be provided instead of the check valve 4 and the differential pressure valve 8. In this case, the inflow of steam into the heat exchanger 6 and the discharge of condensate from the strainer 2 can be appropriately controlled by detecting the internal pressure of either or both of the primary side pipe and the secondary side pipe with a sensor, transmitting the detected data to a controller by wire or wirelessly, and controlling the opening and closing of the solenoid valve based on the internal pressure received and recognized by the controller. [Explanation of symbols]

[0037] 2: Strainer 4: Check valve 6: Heat exchanger 8: Differential pressure valve 11: Inlet piping 12: Outlet piping a1, a2: value

Claims

1. A strainer section that allows steam flowing in from a primary piping to pass through and flows out to a secondary piping, and captures foreign matter mixed in the steam; a heat exchange section that dissipates heat from the steam to generate drainage and supplies the drainage to the strainer section to clean the strainer section; a generating valve means for opening and feeding the steam to the heat exchange section when the internal pressure of the primary side piping reaches a predetermined generating reference pressure; A strainer cleaning system comprising:

2. In the strainer cleaning system according to claim 1, a discharge valve means for opening to discharge the drain in the strainer portion when the internal pressure of the primary piping becomes higher than the internal pressure of the secondary piping and the pressure difference reaches a discharge standard pressure difference as a discharge standard condition; It is equipped with The discharge standard condition is met after the heat exchange section provides the drain to the strainer section. A strainer cleaning system comprising:

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