JP2012145273A - Method of cleaning inside of heat transfer tube of heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of cleaning the inside of a heat transfer tube of a heat exchanger, while improving work efficiency in inserting a nozzle into the heat transfer tube and reducing cleaning costs.SOLUTION: In cleaning the heat transfer tube 3 (3A), a tip of a body section 11 of a guide member 10 is brought into contact with the heat transfer tube 3A to be cleaned while inserting an anchor pin 13 into an adjacent heat transfer tube 3B. High-pressure water is supplied to the nozzle 5, so that the high-pressure water is jetted from a jetting port 5a of the nozzle 5, and a flexible hose 6 is delivered by a driving device 20. Thus, the nozzle 5 is moved and advanced into the heat transfer tube 3A to be cleaned from the guide member 10 while jetting the high-pressure water. After the flexible hose 6 is delivered by a predetermined length, the flexible hose 6 is retracted.

Description

  The present invention relates to a method for cleaning a heat transfer tube of a heat exchanger, and more particularly to a method for cleaning by inserting a nozzle into the heat transfer tube.

  As a method of cleaning the inner surface of the heat transfer tube of the heat exchanger, a nozzle is inserted into the heat transfer tube from the heat transfer tube opening exposed to the tube plate, and high pressure cleaning water supplied from a flexible hose connected to the rear end of the nozzle is used for the nozzle. The method of making it blow out toward the inner surface of a heat exchanger tube is performed.

  In order to increase the efficiency of the cleaning operation and save labor in the cleaning operation, in Patent Document 1 (Japanese Patent Laid-Open No. 7-19793) and Patent Document 2 (Japanese Patent Laid-Open No. 2002-48492), the flexible hose is moved by a motor. Are listed. In Patent Document 2, the flexible hose is wound around a drum. After inserting the nozzle into the heat transfer tube, the nozzle is advanced in a self-propelled manner by reversely jetting high-pressure washing water (spouting backward). After the nozzle has advanced to the set position, the nozzle is retracted by winding with a drum. The operator inserts the nozzle into the heat transfer tube.

  In Patent Document 1, a unit including a hose drum, a hose running roller, and a hose guide guide pipe is installed at the tip of the robot arm. With this robot arm, the guide pipe faces the opening of the heat transfer tube to be cleaned, the hose is sent into the heat transfer tube by the roller, and the hose is advanced and retracted while high pressure cleaning water is ejected from the nozzle at the tip of the hose toward the inner surface of the heat transfer tube. . The position data of each heat transfer tube opening is input to the robot arm control device in advance, and after cleaning of one heat transfer tube is completed, the unit is moved to the next heat transfer tube by the robot arm, and each heat transfer tube is moved. Wash one after another.

JP-A-7-19793 JP 2002-48492 A

  In the cleaning method of Patent Document 2, the operator guides and inserts the nozzle at the tip of the flexible hose into the heat transfer tube opening. However, this work requires labor and labor.

  In Patent Document 1, since the robot arm is used, the working efficiency is improved, but the equipment is expensive and the cleaning cost is increased.

  It is an object of the present invention to provide a method for cleaning a heat exchanger tube of a heat exchanger that is excellent in the efficiency of inserting a nozzle into a heat exchanger tube and is low in cleaning cost.

  In the heat exchanger cleaning method for a heat exchanger according to the present invention (Claim 1), a nozzle is inserted into the heat transfer tube from the opening of the heat transfer tube exposed to the tube plate, and supplied from a flexible hose connected to the rear end of the nozzle. The cleaning water is ejected from the nozzle toward the inner surface of the heat transfer tube and the inner surface of the heat transfer tube is cleaned by advancing and retracting the flexible hose to insert the nozzle into the heat transfer tube to be cleaned. In doing so, in the cleaning method in the heat transfer tube of the heat exchanger, the guide member is arranged facing the opening of the heat transfer tube to be cleaned, and the nozzle is inserted into the heat transfer tube to be cleaned from the guide member. An anchor pin is provided in the guide member, and the guide member is arranged by inserting the anchor pin into an opening of the heat transfer tube in the vicinity of the heat transfer tube to be cleaned in the tube plate.

  According to a second aspect of the present invention, there is provided a heat exchanger tube cleaning method according to the first aspect, wherein the guide member is provided with a plurality of anchor pins, and each anchor pin is inserted into a separate heat transfer tube opening. Features.

  A method for cleaning a heat exchanger tube of a heat exchanger according to claim 3 is the method according to claim 1 or 2, wherein the flexible hose is sandwiched between a pair of rollers provided in the flexible hose advancement / retraction device, and the flexible hose is advanced / retracted by the roller. A mark is provided on the flexible hose, and the mark is detected by a sensor to control the advance and retreat of the flexible hose.

  According to a fourth aspect of the present invention, there is provided a method for cleaning a heat exchanger tube of a heat exchanger according to the third aspect, wherein the flexible hose advancement / retreat apparatus is provided with a chuck capable of gripping the flexible hose, and the flexible hose is gripped and fixed during cleaning standby. It is characterized by doing.

  The method for cleaning a heat exchanger tube of a heat exchanger according to claim 5 is the method according to any one of claims 1 to 4, wherein the nozzle is disposed in the guide member, and the guide member is disposed at the opening of the heat transfer tube to be cleaned. The high pressure water is ejected from the nozzle, the nozzle is advanced, and the nozzle from which the high pressure water is ejected is inserted into the heat transfer tube.

  The method of cleaning a heat exchanger tube of a heat exchanger according to claim 6 is the method according to any one of claims 1 to 5, wherein the nozzle from which high pressure water is jetted is pulled out of the heat transfer tube to be cleaned and then the high pressure from the nozzle is extracted. The water jet is stopped.

  In the method for cleaning a heat exchanger tube of the heat exchanger according to the present invention, the guide member is disposed facing the opening of the heat transfer tube to be cleaned, and the nozzle is provided on the guide member when the nozzle is inserted from the guide member into the heat transfer tube to be cleaned. The guide pin is fixed by inserting the anchor pin into the heat transfer tube near the heat transfer tube to be cleaned. The nozzle can be advanced from this guide member and smoothly inserted into the heat transfer tube to be cleaned, and the heat transfer tube can be cleaned efficiently. Further, in the present invention, an expensive robot apparatus is unnecessary and the cleaning cost is low.

  In the present invention, after the guide member is installed, the nozzle can be inserted into the heat transfer pipe to be cleaned in a state where high pressure water is jetted from the nozzle, and the nozzle from which the cleaning water is jetted in the heat transfer pipe is washed. Since the water can be drawn into the guide member while being ejected, the opening, that is, the end of the heat transfer tube can be sufficiently cleaned. Even when cleaning water is ejected from the nozzle when the nozzle is retracted into the guide member, the ejected water is not scattered outside the guide member.

  By providing a plurality of anchor pins and inserting each anchor pin into another heat transfer tube opening, the installation of the guide member is stabilized.

  In the present invention, the flexible hose can be smoothly advanced and retracted by sandwiching the flexible hose between the pair of rollers of the flexible hose advancement / retraction device and rotating the roller. In this case, it is possible to know the insertion position of the nozzle by providing a mark on the flexible hose and detecting the mark with a sensor.

  Further, the flexible hose can be kept in the advance / retreat stopped state by gripping the flexible hose with the chuck provided in the flexible hose advance / retreat apparatus.

It is explanatory drawing of the washing | cleaning method in the heat exchanger tube of the heat exchanger which concerns on embodiment. It is explanatory drawing of the washing | cleaning method in the heat exchanger tube of the heat exchanger which concerns on embodiment. It is the III-III sectional view taken on the line of FIG. FIG. 4 is a partially enlarged view of FIG. 3. It is the VV sectional view taken on the line of FIG.

  Hereinafter, embodiments will be described with reference to FIGS.

  As shown in FIG. 1, a tube plate 2 is provided in a heat exchanger 1, and one end of a large number of heat transfer tubes 3 is fixed to the tube plate 2 by welding. As shown in FIG. 3, the heat transfer tube 3 passes through the tube plate 2, and an opening on one end side thereof opens toward the water chamber 4 of the heat exchanger 1. As shown in FIG. 5, the heat transfer tubes 3 are arranged in a staggered arrangement in this embodiment.

  When the inside of the heat transfer tube 3 is washed with high-pressure water, the guide member 10 is disposed so as to face the heat transfer tube 3 (3A) to be cleaned as shown in FIGS. The nozzle 5 is inserted into the heat transfer tube 3 </ b> A from the guide member 10, and the high-pressure water supplied through the flexible hose 6 is ejected from the ejection hole 5 a of the nozzle 5.

  The guide member 10 includes a substantially cylindrical main body portion 11 having a nozzle insertion hole 11a, a block portion 12 provided on the front end side of the main body portion 11, and a plurality of (this) In the embodiment, two anchor pins 13 are provided. The front end surface of the block unit 12 is flush with the front end surface of the main body unit 11. The anchor pin 13 protrudes forward from the block portion 12. The anchor pin 13 has an outer diameter that is slightly smaller than the inner diameter of the heat transfer tube 3. The tip side of the anchor pin 13 has a hemispherical shape to facilitate insertion into the heat transfer tube 3.

  The distal end side of the guide tube 14 is connected to the rear end side of the main body 11. The rear end side of the guide tube 14 is connected to a machine frame 21 of the flexible hose driving device 20 as shown in FIG.

  The flexible hose driving device 20 includes a pair of rollers 22 that sandwich the flexible hose 6 and is configured to advance and retract the flexible hose 6 by driving the rollers 22 with a motor. In this embodiment, a flexible hose is sandwiched between a lower roller and an upper roller, and insertion / extraction is performed by an air motor (not shown) connected to the lower roller. By operating an air cylinder (not shown) connected to the upper roller, the upper roller is pressed against the lower roller, and the flexible hose is sandwiched.

  The flexible hose driving device 20 is provided with a chuck 23 (which is composed of an air hand in this embodiment) that can hold the flexible hose 6 and keep the flexible hose 6 in a stopped state. This is to prevent the flexible hose from moving when the flexible hose is not inserted or withdrawn, and also to prevent the flexible hose from running on its own. Marks (not shown) such as tapes of different colors are attached to the flexible hose 6 by winding them around a predetermined position, and the flexible hose driving device 20 detects this mark and determines the position of the nozzle 5 from the feed amount of the flexible hose 6. A color sensor 24 is provided for detecting the above.

  Each flexible hose 6 extends long through each flexible hose driving device 20, and its end is connected to the outflow port of the three-way valve 31 of the high-pressure three-way valve unit 30. A main pipe 33 of high pressure water is connected to the inflow port of the three-way valve 31. A pressure regulating valve 34 is connected to the third port of the three-way valve 31. Thereby, even if the supply of the high-pressure water to one flexible hose 6 is stopped, the fluctuation of the high-pressure water pressure of the other flexible hose 6 is prevented. By providing the pressure regulating valve 34 with the same differential pressure as that of the nozzle, it is possible to prevent a pressure drop in the high pressure system.

  In this embodiment, the drive system is air and the control system / operation system / sensing is electrically performed in the apparatus, and the control panel 40 is installed to perform these controls.

  As shown in FIG. 2, an air switch 41 and a pendant switch 42 in the water chamber 4 and a remote emergency stop switch 43 are connected to the control panel 40. The flexible hose driving device 20 and the high-pressure three-way valve unit 30 are operated by signals from the control panel 40. The pendant switch is for an operator to manually operate the device, and has an emergency stop button.

  The air switch 41 is disposed in the vicinity of the guide member 10. By operating the air switch 41, the apparatus can be operated, and a series of operations of inserting / extracting the flex and supplying / stopping the high-pressure water can be executed.

  When cleaning the heat transfer tube 3, the nozzle 5 is disposed in the guide member 10 as shown in FIGS. An operator who has entered the water chamber 4 brings the guide member 10 close to the heat transfer tube 3A to be cleaned, and inserts the anchor pin 13 into the adjacent heat transfer tube 3B, while the tip of the main body 11 of the guide member 10 is moved to the heat transfer tube 3A to be cleaned. Abut. As a result, the nozzle insertion hole 11a of the main body 11 and the inner hole of the heat transfer tube 3A are in a fixed installation state in which the guide member is arranged coaxially.

  In this state, high-pressure water is supplied to the nozzle 5, high-pressure water is ejected from the ejection holes 5 a of the nozzle 5, and the flexible hose 6 is sent out by the flexible hose driving device 20. As a result, the nozzle 5 moves from the guide member 10 into the cleaning target heat transfer tube 3A while jetting high-pressure water, and further advances in the heat transfer tube 3A. When it is detected that the flexible hose 6 has been sent out by a predetermined length, the flexible hose driving device 20 moves the flexible hose 6 backward. Thereby, the nozzle 5 moves backward in the heat transfer tube 3A while jetting high-pressure water. If the nozzle 5 is retracted into the guide member 10, the flexible hose 6 is stopped and the ejection of high-pressure water is stopped.

  Since the cleaning of the first heat transfer tube 3 is completed by the above procedure, the guide member 10 is transferred to the heat transfer tube 3 adjacent to the heat transfer tube 3 that has been cleaned, and the heat transfer tube 3 is cleaned in the same manner. This process is performed one after another, and all the heat transfer tubes 3 are cleaned.

  According to this embodiment, since the nozzle 5 is advanced in a fixed installation state in which the main body portion 11 of the guide member 10 is in contact with the cleaning target heat transfer tube 3A coaxially, high pressure water is ejected from the nozzle 5. Even in the state, the nozzle 5 can be smoothly inserted into the heat transfer tube 3A. For this reason, the cleaning work efficiency of the heat transfer tube is improved. Moreover, expensive robot equipment is not required and the cleaning cost is low. By making the speed of the nozzle 5 constant, the cleaning state is uniform and uniform.

  In this embodiment, the nozzle 5 ejecting high-pressure water is moved from the guide member 10 into the heat transfer tube 3A, and the nozzle 5 ejecting high-pressure water is pulled out from the heat transfer tube 3A into the guide member 10. Thus, the end portion of the heat transfer tube 3A is also sufficiently cleaned. Further, even if high pressure water is ejected from the nozzle 5 in the guide member 10, this water does not scatter around. Therefore, the working environment in the water chamber 4 is also good.

  In this embodiment, since the two anchor pins 13 are provided in the guide member 10, the fixed installation state of the guide member 10 becomes stable.

According to the cleaning method inside the heat transfer tube of this heat exchanger,
(1) Accidents due to mishandling of the flexible hose can be prevented.
(2) The load of the flexible hose pull-out operation can be greatly reduced, and heavy labor in a poor environment can be reduced.
(3) Insertion and extraction are performed at a constant speed with a motor, and the cleaning state can be made uniform and of good quality.
Various excellent effects such as these are exhibited.

  In this embodiment, as shown in FIG. 4, the ejection hole 5a of the nozzle 5 is provided so as to be directed rearward with respect to the forward direction. For this reason, when high-pressure water is ejected from the ejection holes 5a, a propulsive force is applied to the nozzle 5. Therefore, when the nozzle 5 moves forward, the nozzle 5 may be moved forward only by releasing the chuck 23 of the flexible hose driving device 20.

  In this embodiment, two flexible hoses 6 are connected to the high-pressure three-way valve unit 30 so that the two heat transfer tubes 3 can be simultaneously cleaned by the two guide members 10 in the water chamber 4. The number of lines of 6 may be 1 or 3 or more.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Tube plate 3 Heat transfer tube 4 Water chamber 5 Nozzle 6 Flexible hose 10 Guide member 13 Anchor pin 20 Flexible hose drive device

Claims (6)

A nozzle is inserted into the heat transfer tube from the opening of the heat transfer tube exposed to the tube plate, and the washing water supplied from the flexible hose connected to the rear end of the nozzle is ejected from the nozzle toward the inner surface of the heat transfer tube, and the flexible hose A method of cleaning the inner surface of the heat transfer tube by moving the nozzle back and forth by moving back and forth.
When inserting the nozzle into the heat transfer tube to be cleaned, the guide member is arranged facing the opening of the heat transfer tube to be cleaned,
In the cleaning method in the heat transfer tube of the heat exchanger in which the nozzle is inserted into the cleaning target heat transfer tube from the guide member,
An anchor pin is provided on the guide member,
A method for cleaning an inside of a heat exchanger tube of a heat exchanger, wherein the guide member is arranged by inserting the anchor pin into an opening of a heat exchanger tube in the vicinity of a heat transfer tube to be cleaned in the tube plate.   2. The method of cleaning a heat exchanger tube of a heat exchanger according to claim 1, wherein the guide member is provided with a plurality of anchor pins, and each anchor pin is inserted into a separate heat exchanger tube opening. In claim 1 or 2, the flexible hose is sandwiched between a pair of rollers provided in the flexible hose advancement and retraction device, and the flexible hose is advanced and retracted by the roller.
A method for cleaning a heat exchanger tube of a heat exchanger, wherein a mark is provided on the flexible hose, and the mark is detected by a sensor to control the advance and retreat of the flexible hose. In claim 3, the flexible hose advancement and retraction device is provided with a chuck capable of gripping the flexible hose,
A method for cleaning a heat exchanger tube of a heat exchanger, wherein the flexible hose is held and fixed by the chuck during standby for cleaning. In any one of Claims 1 thru | or 4,
Placing the nozzle in the guide member;
The guide member is placed facing the opening of the heat transfer tube to be cleaned,
A method of cleaning a heat transfer tube of a heat exchanger, wherein high pressure water is ejected from the nozzle and the nozzle is started to advance, and the nozzle from which high pressure water is ejected is inserted into the heat transfer tube. In any one of Claims 1 thru | or 5,
A method for cleaning an inside of a heat exchanger tube of a heat exchanger, characterized in that after the nozzle ejecting high pressure water is pulled out of the heat transfer tube to be cleaned, the injection of high pressure water from the nozzle is stopped.

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