JP2008190788A - Maintenance device of heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a maintenance device capable of measuring the level of contamination inside of a heat exchanger with high accuracy and cleaning the inside of the heat exchanger according to necessity. <P>SOLUTION: This maintenance device 2 of the heat exchanger 11 exchanging heat between heat source water and heat-exchanged fluid, has a tank 51 for storing the water or cleaning fluid, an upstream-side pipe 55 connected to a going-side pipe 15 for supplying the heat source water to the heat exchanger 11, a downstream-side pipe 56 connected to a returning-side pipe 18 for discharging the heat source water from the heat exchanger 11, a pump 60 for circulating the water or cleaning fluid to the heat exchanger 11 through the upstream-side pipe 55 and the downstream-side pipe 56, a flow rate adjustment valve 65 for adjusting a flow rate of the water or cleaning fluid circulated to the heat exchanger 11, a flowmeter 67 for measuring the flow rate of the water or cleaning fluid circulated in the heat exchanger 11, and a differential-pressure meter 75 for measuring differential pressure between the heat source water and the water or cleaning fluid between the upstream and downstream of the heat exchanger 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a maintenance device capable of inspecting the degree of dirt inside a heat exchanger and cleaning the inside of the heat exchanger as necessary.

  For example, heat exchangers are often used in building facilities and production facilities. There are various types of heat exchangers. Among them, brazing plate type heat exchangers that can perform compact and highly efficient heat exchange have been widely used in recent years.

  However, since the brazing plate heat exchanger has a narrow flow path width of, for example, 2 to 3 mm, when the water of the open cooling tower or the groundwater with high hardness is circulated as the heat source water, dirt adheres to the inside and circulates. Problems such as a decrease in the flow rate and heat exchange amount and an increase in circulation pump power are likely to occur. Therefore, for brazing plate heat exchangers, it is common to install pressure gauges and water thermometers on the upstream and downstream sides of the heat exchanger, and periodically check these values to investigate the degree of internal contamination. ing.

  Moreover, when investigating the degree of internal contamination, it is necessary to measure the flow rate of the heat source water. However, since flow meters are expensive, for example, when many brazing plate heat exchangers are installed in building equipment, production equipment, etc., one flow meter should not be installed in each heat exchanger. Instead, it is common to mount a clamp-on type ultrasonic flowmeter on the pipe only when necessary, and measure from the outside.

In addition, as a heat exchanger of a system other than the brazing plate heat exchanger, for example, a multi-tube heat exchanger, etc., high pressure washing water is sprayed from the nozzle to the peripheral surface of the heat transfer tube to remove the adhesion scale and the like. (For example, Patent Document 1). However, in the brazing plate type heat exchanger, the flow path of the heat source water is not exposed to the outside and the structure cannot be disassembled and washed, so the high pressure washing water is jetted from the nozzle to wash the inside. It is impossible. For this reason, in the brazing plate heat exchanger, as described above, pressure gauges and water temperature gauges are installed upstream and downstream of the heat exchanger to investigate the degree of internal contamination. Such cleaning liquid is circulated inside the heat exchanger for cleaning.
Utility Model Registration No. 2533754

However, the conventional method has the following problems.
(1) Poor measurement accuracy of heat exchanger pressure loss When pressure gauges are installed upstream and downstream of the heat exchanger, and the pressure loss between the upstream and downstream of the heat exchanger is measured by comparing the measured values of the two pressure gauges. When the pressure loss due to the heat exchanger is small relative to the measurement range of the pressure gauge, the pressure loss value of the heat exchanger obtained from the difference between the measurement values of the two pressure gauges becomes low accuracy. For example, the accuracy of a Bourdon tube type pressure gauge (range 100 [kPa]) generally used is ± 1.5 to 3 [kPa], and an error when trying to measure a pressure loss of 10 [kPa] is as follows: 15 to 30% or more. In order to measure the pressure loss in the heat exchanger with high accuracy, it is necessary to install a micro differential pressure gauge. However, since the micro differential pressure gauge is more expensive than a Bourdon tube pressure gauge, there is a slight difference for each heat exchanger. It is economically difficult to install one pressure gauge at a time.

(2) Poor accuracy of heat exchanger circulating flow rate When measuring the heat exchanger circulating flow rate with a clamp-on type ultrasonic flow meter, it becomes impossible to measure depending on the piping material, or the inner diameter of the tube is reduced due to rust. May cause errors. In order to measure the flow rate with high accuracy, it is reliable to install an electromagnetic flow meter in the middle of the pipe. However, since it cannot be removed, it is necessary to install one unit for each heat exchanger. Difficult to install.

(3) Unclearness of cleaning effect of heat exchanger As described in (1) and (2), it is difficult to measure the pressure loss and circulation flow rate of the heat exchanger economically and with high accuracy. Even if the exchanger is cleaned, it is difficult to quantitatively grasp the effect. Therefore, there is a possibility that the amount of chemicals used for cleaning and the cleaning time may be excessive or insufficient.

  Accordingly, an object of the present invention is to provide a maintenance device that can accurately measure the degree of dirt inside the heat exchanger and can also clean the inside of the heat exchanger as necessary. .

  According to the present invention, a heat exchanger maintenance device for exchanging heat between heat source water and a heat exchange fluid includes a tank for storing water or cleaning liquid, and a forward side pipe for supplying heat source water to the heat exchanger. Circulating water or cleaning liquid to the heat exchanger through the upstream pipe connected, the downstream pipe connected to the return pipe discharging the heat source water from the heat exchanger, and the upstream pipe and the downstream pipe A flow control valve for adjusting the flow rate of water or cleaning liquid to be circulated to the heat exchanger, a flow meter for measuring the flow rate of water or cleaning liquid to be circulated to the heat exchanger, and the heat exchanger There is provided a maintenance device comprising a heat source water between upstream and downstream and a differential pressure gauge for measuring a differential pressure of water or cleaning liquid.

  According to the present invention, there is also provided a heat exchanger maintenance device for exchanging heat between the heat source water and the heat exchange fluid, a tank for storing water or a cleaning liquid, and a forward side for supplying the heat source water to the heat exchanger. An upstream pipe connected to the pipe, a downstream pipe connected to a return pipe that discharges heat source water from the heat exchanger, and water or cleaning liquid to the heat exchanger through the upstream pipe and the downstream pipe A flow rate variable pump that circulates the heat exchanger, a flow meter that measures the flow rate of water or cleaning liquid circulated to the heat exchanger, and a difference that measures the differential pressure of the heat source water and water or cleaning liquid between the upstream and downstream of the heat exchanger A maintenance device is provided, comprising a pressure gauge.

  In the present invention, the heat exchanger is, for example, a brazing plate heat exchanger. As the differential pressure gauge, a fine differential pressure gauge capable of low pressure measurement can be used.

  According to the present invention, the pressure loss can be measured with high accuracy by measuring the pressure loss of the heat source water and water or the cleaning liquid in the heat exchanger as the differential pressure between the upstream and downstream of the heat exchanger. In addition, by measuring the flow rate of water or cleaning liquid circulated through the heat exchanger, it becomes possible to grasp the contamination of the heat exchanger with high accuracy and economically. Thereby, the cleaning operation of the heat exchanger can be efficiently performed without excess or deficiency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Drawing 1 is an explanatory view of air-conditioning system 1 in the state where maintenance device 2 concerning an embodiment of the invention was attached. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The illustrated air conditioning system 1 includes a building multi-type air conditioning facility 10 that performs a cooling operation of a building, a heat exchanger 11 that processes a cooling load of the air conditioning facility 10, and cooling the heat exchanger 11 as heat source water. A heat source facility 12 for circulating and supplying water is provided. As the heat exchanger 11, a brazing plate heat exchanger in which metal plates having excellent heat conductivity are integrated by brazing is used. In FIG. 1, only one heat exchanger 11 is shown, but the air conditioning system 1 is provided with a plurality of heat exchangers 11. For each of the plurality of heat exchangers 11, Cooling water is circulated and supplied from the heat source facility 12.

  In the heat source facility 12, cooling water as heat source water cooled by a refrigerator or the like (not shown) is supplied into the heat exchanger 11 from the forward side pipe 15 through the heat source water inlet side flow path 16, and in the heat exchanger 11. The cooling water after the heat exchange is returned from the heat source water outlet side flow path 17 to the refrigerator or the like through the return side pipe 18. The forward side pipe 15 is provided with an on-off valve 20 for controlling the supply of cooling water to the heat exchanger 11, a strainer 21 for removing foreign substances in the cooling water, and a water temperature meter 22 for measuring the forward side temperature of the cooling water. It has been. The return side pipe 18 is provided with a water temperature gauge 25 for measuring the return side temperature of the cooling water, and an on-off valve 26 for controlling the discharge (flow rate) of the cooling water to the refrigerator or the like.

  The air conditioning equipment 10 includes an indoor unit 30 and an outdoor unit 31. The air conditioning system 1 is provided with a plurality of indoor units 30 and outdoor units 31. The indoor unit 30 includes a coil 35, a fan 36, and an expansion valve 41. A heat transfer fluid as a heat exchange fluid cooled by cooling water in the heat exchanger 11 is supplied to the coil 35 via the liquid pipe 40 and the expansion valve 41 in the indoor unit 30. Air to be conditioned is blown into the indoor unit 30 by a fan 36, and the air to be conditioned is brought into thermal contact with the coil 35 to be cooled. The air-conditioning target air thus cooled is supplied to an air-conditioning area formed inside a building or the like.

  In addition, the heat medium gas as the heat exchange fluid that has been heated up relatively by cooling the air to be air-conditioned and is vaporized is supplied to the outdoor unit 31 through the gas pipe 42. The outdoor unit 31 includes a compressor 44 and a cooling coil 45, and the heat medium gas boosted by the compressor 44 is condensed and liquefied by cooling it with outside air in the cooling coil 45. Thus, the heat transfer fluid as the heat exchange fluid liquefied in the outdoor unit 31 is returned to the heat exchanger 11 again through the liquid pipe 46.

  The maintenance device 2 has a configuration in which a tank 51 for storing water (fresh water) or cleaning liquid is mounted on a movable carriage 50. The cleaning liquid is, for example, a chemical liquid. As will be described later, water is used for measuring the degree of contamination inside the heat exchanger 11 provided in the air conditioning system 1 and rinsing the cleaning liquid, and the cleaning liquid is used for cleaning the inside of the heat exchanger 11.

  The maintenance device 2 is connected to an upstream pipe 55 connected to an outgoing pipe 15 that supplies cooling water as heat source water to the heat exchanger 11, and to a return pipe 18 that returns the cooling water from the heat exchanger 11. A downstream pipe 56 is provided. For the upstream side pipe 55 and the downstream side pipe 56, for example, a hose made of a material excellent in flexibility and chemical resistance, for example, heat-resistant PVC is used. By configuring the upstream pipe 55 and the downstream pipe 56 with such hoses, the pipes can be folded compactly when not in use. The maintenance device 2 can be attached to the air conditioning system 1 by moving the maintenance device 2 to the vicinity of the air conditioning system 1 and connecting the upstream side piping 55 and the downstream side piping 56 to the outgoing side piping 15 and the return side piping 18. .

  When the maintenance device 2 is attached to the air conditioning system 1, one end of the upstream pipe 55 is connected to the forward pipe 15 between the on-off valve 20 and the heat exchanger 11, and one end of the downstream pipe 56 is connected to the on-off valve. 26 and the heat exchanger 11 are connected to the return side pipe 18.

  The other end of the upstream pipe 55 is attached with a pump 60 for sending water or cleaning liquid in the tank 51 to the heat exchanger 11 via the upstream pipe 55. The upstream pipe 55 is provided with an open / close valve 61 disposed at a position close to the forward pipe 15 and an open / close valve 62 disposed at a position close to the tank 51 (pump 60). Further, between the on-off valve 62 and the pump 60, the liquid is sent to the heat exchanger 11 via a three-way valve 65 as a flow control valve, a strainer 66 for removing foreign substances in water or cleaning liquid, and an upstream pipe 55. An electromagnetic flow meter 67 is provided for measuring the flow rate of the water or cleaning liquid. A bypass circuit 68 is connected to the three-way valve 65, and excess water or cleaning liquid generated when the flow rate is adjusted by the three-way valve 65 passes through the other end of the downstream pipe 56 described below from the bypass circuit 68. It is returned to the tank 51. The on-off valves 61 and 62 and the three-way valve 65 can be made of, for example, engineering plastics having excellent chemical resistance and heat resistance.

  The other end of the downstream pipe 56 is disposed above the tank 51. Further, a filter 70 is disposed below the other end of the downstream pipe 56, and water or cleaning liquid discharged from the other end of the downstream pipe 56 returns to the tank 51 through the filter 70 as will be described later. It is supposed to be. Note that excess water or cleaning liquid generated when the flow rate is adjusted by the three-way valve 65 described above is also returned from the bypass circuit 68 to the tank 51 through the other end of the downstream pipe 56. The downstream side pipe 56 is provided with an on-off valve 71 disposed at a position close to the return side pipe 18 and an on-off valve 72 disposed at a position close to the tank 51. The on-off valves 71 and 72 can be made of, for example, engineering plastics having excellent chemical resistance and heat resistance.

  The maintenance device 2 includes a differential pressure gauge 75 that measures a differential pressure between water or cleaning liquid in the upstream pipe 55 and water or cleaning liquid in the downstream pipe 56. The differential pressure gauge 75 includes the pressure of water or cleaning liquid in the upstream pipe 55 between the on-off valve 61 and the on-off valve 62, and the pressure of water or cleaning liquid in the downstream pipe 56 between the on-off valve 71 and the on-off valve 72. The difference (differential pressure) is measured. As the differential pressure gauge 75, for example, a fine differential pressure gauge capable of measuring a pressure loss of about 10 [kPa] is used.

  Next, a method for inspecting the degree of dirt inside the heat exchanger 11 of the air conditioning system 1 using the maintenance device 2 configured as described above and cleaning the inside of the heat exchanger 11 as necessary will be described. To do.

  During normal operation by the air conditioning system 1, the cooling water is circulated and supplied to the heat exchanger 11 through the outward piping 15 and the return piping 18 of the heat source facility 12. Further, in the air conditioning facility 10, the cooling operation of the air conditioning region is performed using the cooling water of the cooling water supplied to the heat exchanger 11 in this way. In this case, the open / close valve 20 of the forward side pipe 15 and the open / close valve 26 of the return side pipe 18 are opened.

  On the other hand, when inspecting the inside of the heat exchanger 11 of the air conditioning system 1, as shown in FIG. 1, the maintenance device 2 is moved to the vicinity of the air conditioning system 1 and one end of the upstream pipe 55 is opened and closed. By connecting to the return side pipe 15 between the valve 20 and the heat exchanger 11, and connecting one end of the downstream side pipe 56 to the return side pipe 18 between the on-off valve 26 and the heat exchanger 11, The maintenance device 2 is attached to the air conditioning system 1.

  First, the pressure loss V1 of the heat exchanger 11 is measured. In this case, water is put into the tank 51 of the maintenance device 2. Then, the on-off valve 20 of the outgoing side pipe 15 and the on-off valve 26 of the return side pipe 18 are closed, and the circulation supply of the cooling water to the heat exchanger 11 is stopped. Further, the on-off valves 61 and 62 of the upstream pipe 55 and the on-off valves 71 and 72 of the downstream pipe 56 are opened. Then, the pump 60 is operated to fill the water in the tank 51 into the inside of the upstream side pipe 55 connected to the outgoing side pipe 15 and the inside of the downstream side pipe 56 connected to the return side pipe 18.

  After filling the inside of the upstream pipe 55 and the inside of the downstream pipe 56 with water, the operation of the pump 60 is stopped, and the on-off valves 62 and 72 are closed. Then, as shown in FIG. 2, the on-off valve 20 of the upstream pipe 55 and the on-off valve 26 of the downstream pipe 56 are opened. Thereby, the cooling water of the heat source facility 12 is circulated and supplied to the heat exchanger 11 again through the outward piping 15 and the return piping 18. The on-off valves 61 and 71 remain open.

  In this state, the differential pressure between the water in the upstream pipe 55 and the water in the downstream pipe 56 is measured by the differential pressure gauge 75. Thereby, when the cooling water is circulated and supplied to the heat exchanger 11 by the heat source facility 12, the pressure loss (differential pressure) V1 generated between the upstream and downstream of the heat exchanger 11 is accurately detected by the differential pressure gauge 75. It becomes possible to measure.

  Next, the flow rate of the cooling water in the heat exchanger 11 is measured. In this case, as shown in FIG. 3, the on-off valve 20 of the outgoing side pipe 15 and the on-off valve 26 of the return side pipe 18 are closed, and the circulation of the cooling water from the heat source facility 12 to the heat exchanger 11 is stopped. Further, the on-off valves 61 and 62 of the upstream pipe 55 and the on-off valves 71 and 72 of the downstream pipe 56 are opened. Then, the pump 60 is operated to circulate and supply the water in the tank 51 to the heat exchanger 11 through the upstream pipe 55 and the downstream pipe 56.

  Next, the differential pressure V2 between the water in the upstream side pipe 55 and the water in the downstream side pipe 56 is measured by the differential pressure gauge 75, and the amount of circulating water is measured by the electromagnetic flow meter 67. The differential pressure measured here is the total value of the pressure loss in the heat exchanger 11 and the pressure loss in the upstream side pipe 55 and the downstream side pipe 56. When the latter is relatively larger than the former (for example, when the upstream pipe 55 and the downstream pipe 56 are long), the latter value is estimated from the amount of circulating water. It is generally known that the pipe pressure loss is approximately proportional to the square of the circulating water volume, and the proportionality factor is determined by the material and the inner diameter of the inner surface of the pipe. When the material of the pipe inner surfaces of the upstream pipe 55 and the downstream pipe 56 is PVC and the inner diameter (hose inner diameter) is 32 mm, the pipe pressure loss (pressure loss in the hose) and the amount of circulating water have a relationship as shown in FIG.

  The pressure loss in the upstream pipe 55 and the downstream pipe 56 is estimated from the circulating water amount and FIG. 4, and the circulating water amount is adjusted by the three-way valve 65 so that the value obtained by adding this value to the pressure loss V1 is equal to the pressure loss V2. Since the amount of circulating water slightly changes due to this adjustment, the pressure loss in the upstream pipe 55 and the downstream pipe 56 is estimated again from FIG. 4 and the three-way valve 65 is adjusted. This operation is repeated several times to make the adjustment of the three-way valve 65 unnecessary.

  Excess water generated when the flow rate is adjusted by the three-way valve 65 is returned from the bypass circuit 68 to the tank 51 through the other end of the downstream pipe 56. In this case, the water that is circulated and supplied to the heat exchanger 11 and discharged from the other end of the downstream pipe 56 and the water that is discharged from the bypass circuit 68 to the other end of the downstream pipe 56 both pass through the filter 70. After that, it is returned to the tank 51.

  In this manner, the flow rate of water to be circulated and supplied to the heat exchanger 11 can be inevitably set to the same flow rate as when cooling water of the heat source facility 12 is circulated and supplied to the heat exchanger 11. In this state, the flow rate of water sent to the heat exchanger 11 is measured by the electromagnetic flow meter 67. In this way, it is possible to indirectly measure the flow rate when circulating the cooling water of the heat source facility 12 to the heat exchanger 11.

  And the value which divided the square of the flow volume of the cooling water circulated and supplied from the heat source equipment 12 to the heat exchanger 11 by the differential pressure V1 is not substantially lowered from the value at the start of use of the heat exchanger 11 Determines that the inside of the heat exchanger 11 is not dirty.

  If it is determined that the inside of the heat exchanger 11 is not dirty, it is not necessary to clean the inside of the heat exchanger 11 yet, so the maintenance device 2 is removed from the air conditioning system 1 and the cooling operation of the air conditioning system 1 is continued. To do. In addition, when removing the maintenance apparatus 2 from the air conditioning system 1, the driving | operation of the pump 60 is stopped and the on-off valves 61 and 62 of the upstream piping 55 and the on-off valves 71 and 72 of the downstream piping 56 are closed. Then, the upstream side pipe 55 is removed from the forward side pipe 15, and the downstream side pipe 56 is removed from the return side pipe 18. Then, the on-off valve 20 of the outgoing side pipe 15 and the on-off valve 26 of the return side pipe 18 are opened, and the cooling water of the heat source equipment 12 is circulated and supplied to the heat exchanger 11.

  On the other hand, when the value obtained by dividing the square of the flow rate of the cooling water circulated and supplied from the heat source equipment 12 to the heat exchanger 11 by the differential pressure V1 is substantially reduced from the value at the start of use of the heat exchanger 11, It is determined that the inside of the heat exchanger 11 is dirty.

  When it is determined that the inside of the heat exchanger 11 is dirty, the inside of the heat exchanger 11 is washed. In this case, as shown in FIG. 5, the cleaning liquid is put into the tank 51 of the maintenance device 2. In addition, the on-off valve 20 of the return side pipe 15 and the on-off valve 26 of the return side pipe 18 are closed, and the circulation supply of the cooling water to the heat exchanger 11 is stopped. Further, the on-off valves 61 and 62 of the upstream pipe 55 and the on-off valves 71 and 72 of the downstream pipe 56 are opened. Then, the pump 60 is operated, and the cleaning liquid in the tank 51 is circulated and supplied to the heat exchanger 11 through the upstream pipe 55 and the downstream pipe 56.

  When the heat exchanger 11 is cleaned in this way, the three-way valve 65 is adjusted so that the flow rate of the cleaning liquid to be circulated and supplied to the heat exchanger 11 is maximized so that the cleaning effect is increased. In this case, since all of the cleaning liquid fed by the pump 60 is supplied from the upstream pipe 55 to the heat exchanger 11, no cleaning liquid is fed to the bypass circuit 68.

  Then, for example, the pH of the cleaning liquid is periodically checked with a pH meter or the like, and the pump 60 is operated until the cleaning effect of the cleaning liquid is lost, and the cleaning liquid is circulated and supplied to the heat exchanger 11. Thereafter, the cleaning liquid is added or replaced with a new cleaning liquid, and the process is repeated until the cleaning effect of the cleaning liquid does not change.

  Next, the amount of circulating water is measured by the electromagnetic flow meter 67 and circulated to the heat exchanger 11 so that the measured amount of circulating water is equal to the flow rate of the cooling water circulated and supplied from the heat source facility 12 to the heat exchanger 11. The flow rate of the cleaning liquid to be supplied is adjusted by the three-way valve 65. In this case, excess cleaning liquid generated when the flow rate is adjusted by the three-way valve 65 is returned from the bypass circuit 68 to the tank 51 through the other end of the downstream pipe 56.

  Thus, the flow rate of the cleaning liquid to be circulated and supplied from the tank 51 to the heat exchanger 11 is set to the same flow rate as when the cooling water of the heat source facility 12 is circulated and supplied to the heat exchanger 11. And the differential pressure V3 of the water in the upstream piping 55 and the water in the downstream piping 56 is measured by the differential pressure gauge 75. For example, if the value obtained by dividing the square of the circulating water amount by the differential pressure V3 does not substantially decrease from the value at the start of use of the heat exchanger 11, the inside of the heat exchanger 11 is not dirty. It can be determined that the state has been reached (cleaning has been completed).

  The value obtained by dividing the square of the circulating water amount by the differential pressure V3 is substantially lower than the value at the start of use of the heat exchanger 11, and the inside of the heat exchanger 11 is still dirty (washing is finished). If it is determined that the cleaning liquid in the tank 51 is not replaced, the cleaning liquid in the tank 51 is replaced with a new cleaning liquid, and the cleaning liquid is circulated and supplied into the heat exchanger 11 to continue cleaning.

  In this way, when it is determined that the inside of the heat exchanger 11 has been cleaned with the cleaning liquid and the inside of the heat exchanger 11 has become clean (cleaning is complete), the tank 51 is filled with neutralizing agent and water. It is inserted and circulated through the heat exchanger 11, the cleaning liquid inside the heat exchanger 11 is completely discharged, and the cleaning operation is completed.

  Thereafter, the maintenance device 2 is removed from the air conditioning system 1 and the cooling operation of the air conditioning system 1 is resumed. In addition, when removing the maintenance apparatus 2 from the air conditioning system 1, the driving | operation of the pump 60 is stopped and the on-off valves 61 and 62 of the upstream piping 55 and the on-off valves 71 and 72 of the downstream piping 56 are closed. Then, the upstream side pipe 55 is removed from the forward side pipe 15, and the downstream side pipe 56 is removed from the return side pipe 18. Then, the on-off valve 20 of the outgoing side pipe 15 and the on-off valve 26 of the return side pipe 18 are opened, and the cooling water of the heat source equipment 12 is circulated and supplied to the heat exchanger 11.

  According to the maintenance device 2, the differential pressure gauge 75 and the electromagnetic wave provided in the maintenance device 2 are not installed in the plurality of heat exchangers 11 provided in the air conditioning system 1, without separately installing flow meters and pressure gauges. Since the differential pressure and the circulation flow rate of each heat exchanger 11 are measured using the flow meter 67, in other words, the maintenance device 2 can be reused in a plurality of pipes and a plurality of buildings, so that it is economical. is there. Moreover, if the differential pressure gauge 75 or the electromagnetic flow meter 67 is used, the differential pressure and the circulating flow rate of the heat exchanger 11 can be measured with higher accuracy than a pressure gauge or a clamp-on type ultrasonic flow meter. For this reason, it is possible to accurately measure the degree of contamination inside the heat exchanger 11. In addition, if the water temperature in the upstream and downstream of the heat exchanger 11 is also measured together with the measurement of the circulation flow rate, the heat exchange amount of the heat exchanger 11 can also be measured. In this case, the maintenance device 2 can be used for trial operation and performance verification of building facilities and production facilities. Further, when the heat exchanger 11 is cleaned, the cleaning effect can be confirmed in the middle of the cleaning operation. Therefore, there is no waste of cleaning liquid and excessive or insufficient cleaning time, and an efficient cleaning operation can be performed.

  As mentioned above, although an example of preferable embodiment of this invention was demonstrated, this invention is not limited to the form of illustration. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the ideas described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs. 1 to 3 and 5 show a form in which a flow rate adjusting valve (three-way valve 65) is used to adjust the flow rate of water or cleaning liquid circulated in the heat exchanger 11. On the other hand, in the embodiment shown in FIG. 6, the flow rate adjustment valve is omitted, and instead, a variable flow rate pump 60 ′ is used as a pump for circulating water or cleaning liquid to the heat exchanger 11.

  In the form shown in FIG. 6, the flow rate of the water or the cleaning liquid circulated in the heat exchanger 11 can be adjusted by controlling the pump 60 ′, for example, with an inverter. In this way, the flow rate of water or cleaning liquid fed to the heat exchanger 11 by the electromagnetic flow meter 67 can be measured in the same manner.

  Moreover, although the case where the cooling water was circulated and supplied from the heat source facility 12 to the heat exchanger 11 to perform the cooling operation of the air conditioning facility 10 was described above as an example, the heat source facility 12 circulated and supplied to the heat exchanger 11. The heat source water is not limited to cooling water, and may be hot heat source water for performing a heating operation. Moreover, although the multi-type air conditioning equipment 10 for buildings has been described, the present invention can also be applied to maintenance of heat exchangers provided in other types of air conditioning equipment, production equipment other than air conditioning equipment, and the like. Further, the type of the heat exchanger is not limited to the brazing plate type heat exchanger, and the present invention can be applied to other types of heat exchangers.

  It can be applied to the maintenance of building equipment and production equipment with heat exchangers.

It is explanatory drawing of the air conditioning system of the state which attached the maintenance apparatus concerning embodiment of this invention. It is explanatory drawing of the maintenance apparatus in the case of measuring the pressure loss of a heat exchanger. It is explanatory drawing of the maintenance apparatus in the case of measuring the flow volume of the cooling water in a heat exchanger. It is a graph which shows the relationship between the pressure loss in an upstream piping and downstream piping (hose), and the amount of circulating water (flow volume). It is explanatory drawing of the maintenance apparatus in the case of wash | cleaning the inside of a heat exchanger. It is explanatory drawing of the air conditioning system of the state which attached the maintenance apparatus concerning another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air conditioning system 2 Maintenance apparatus 10 Air conditioning equipment 11 Heat exchanger 12 Heat source equipment 15 Outgoing side piping 18 Return side piping 20 On-off valve 26 On-off valve 50 Carriage 51 Tank 55 Upstream side piping 56 Downstream side piping 60 Pumps 61, 62 On-off valve 65 Three-way valve (flow control valve)
67 Electromagnetic flow meter 71, 71 On-off valve 75 Differential pressure gauge

Claims (3)

A heat exchanger maintenance device that exchanges heat between heat source water and a heat exchange fluid,
A tank for storing water or cleaning liquid;
An upstream pipe connected to an outgoing pipe for supplying heat source water to the heat exchanger;
A downstream pipe connected to a return pipe for discharging heat source water from the heat exchanger;
A pump for circulating water or cleaning liquid through the heat exchanger through the upstream pipe and the downstream pipe;
A flow control valve for adjusting the flow rate of water or cleaning liquid to be circulated in the heat exchanger;
A flow meter for measuring a flow rate of water or cleaning liquid to be circulated in the heat exchanger;
A maintenance apparatus comprising: a heat source water between the upstream and downstream of the heat exchanger and a differential pressure gauge for measuring a differential pressure of water or cleaning liquid. A heat exchanger maintenance device that exchanges heat between heat source water and a heat exchange fluid,
A tank for storing water or cleaning liquid;
An upstream pipe connected to an outgoing pipe for supplying heat source water to the heat exchanger;
A downstream pipe connected to a return pipe for discharging heat source water from the heat exchanger;
A variable flow rate pump that circulates water or cleaning liquid to the heat exchanger through the upstream pipe and the downstream pipe;
A flow meter for measuring a flow rate of water or cleaning liquid to be circulated in the heat exchanger;
A maintenance apparatus comprising: a heat source water between the upstream and downstream of the heat exchanger and a differential pressure gauge for measuring a differential pressure of water or cleaning liquid. The maintenance apparatus according to claim 1, wherein the heat exchanger is a brazing plate heat exchanger.

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