Cooling water temperature adjusting system of water chilling unit

Abstract

The utility model discloses a cooling water temperature adjusting system of a water chilling unit, which relates to the technical field of refrigeration and comprises a cooling water supply pipeline, a cooling water return pipeline, a chilled water supply pipeline, a chilled water return pipeline, a variable frequency water pump, user side equipment and a cooling tower. The problem that the suction and exhaust pressure difference of the compressor is lower than a set value due to the fact that the temperature of the cooling water is too low in a transition season, and then the compressor is in an oil shortage state and stops is effectively solved, normal operation of the water chilling unit is guaranteed, and the service life of the water chilling unit is prolonged. The stability and reliability of the system are improved, accurate adjustment of the temperature of the cooling water is achieved by controlling the operation frequency of the variable frequency water pump, starting and stopping of the cooling tower fan and the opening degree of the electric adjusting valve, the water supply temperature of the cooling water entering the water chilling unit can be stabilized within the preset temperature range, and the operation working condition of the water chilling unit is optimized.

Description

TECHNICAL FIELD

[0001] The utility model relates to refrigeration technical field, especially a kind of cooling water temperature regulating system of water chiller unit. BACKGROUND

[0002] During the operation of water chiller unit, the heat of chilled water is absorbed by refrigerant in evaporator, and the low-temperature and low-pressure liquid is converted into low-temperature and low-pressure gas, and the gaseous refrigerant is compressed by compressor to become high-temperature and high-pressure gas into condenser to transfer heat to cooling water, and is converted into liquid refrigerant again, and the low-temperature and low-pressure liquid formed by throttling expansion device is sent into evaporator to form a cycle.

[0003] As an important component of water chiller unit, lubrication is indispensable, and in screw water chiller unit, differential pressure oil supply is used for compressor bearing oil supply, that is, the pressure difference between compressor refrigerant exhaust and suction is used as the driving force of lubricating oil. However, in the case of low ambient temperature in the transition season, when the unit starts, due to the low temperature of cooling water, the condensation temperature and exhaust pressure are also low, and then the suction and exhaust pressure difference is less than the set value, and the oil supply cannot be realized. At this time, the bearing of compressor is in the state of oil shortage, and if the suction and exhaust pressure difference does not reach the specified value within the set time, the compressor stops, which affects the normal operation of the refrigeration machine. UTILITY MODEL CONTENT

[0004] In view of the deficiencies of the prior art, the utility model provides a cooling water temperature regulating system of water chiller unit, which solves the technical problem that in the case of low ambient temperature in the transition season, when the unit starts, due to the low temperature of cooling water, the condensation temperature and exhaust pressure are also low, and then the suction and exhaust pressure difference is less than the set value, and the oil supply cannot be realized. At this time, the bearing of compressor is in the state of oil shortage, and if the suction and exhaust pressure difference does not reach the specified value within the set time, the compressor stops, which affects the normal operation of the refrigeration machine.

[0005] To achieve the above purpose, the utility model is realized by the following technical scheme:

[0006] A cooling water temperature regulating system of water chiller unit, comprising cooling water supply pipeline and return pipeline, chilled water supply pipeline and return pipeline, frequency conversion water pump, user side equipment and cooling tower;

[0007] One end of the cooling water supply pipeline is connected to the water outlet of the cooling tower and connected to the water supply end of the water chiller unit through the frequency conversion water pump, and the two ends of the cooling water return pipeline are connected to the water return end of the water chiller unit and the water inlet of the cooling tower respectively;

[0008] The two ends of the chilled water supply pipeline are connected to the water supply end of the water chiller unit and the user side equipment respectively, and one end of the chilled water return pipeline is connected to the user side equipment and connected to the water return end of the water chiller unit through the frequency conversion water pump.

[0009] The cooling water temperature adjusting system of the water chilling unit further comprises a cooling water shunt branch, a chilled water supply pipeline, a butterfly valve and a chilled water shunt branch, one end of the cooling water shunt branch is connected with the cooling water supply pipeline, and the cooling water shunt branch is connected with the cooling water return pipeline through the butterfly valve.

[0010] Preferably, the cooling tower is provided with a cooling fan.

[0011] Preferably, the system further comprises pressure sensors and temperature sensors for detecting the water pressure and water temperature in the cooling water supply pipeline, the cooling water return pipeline, the chilled water supply pipeline and the chilled water return pipeline.

[0012] Preferably, the system further comprises electromagnetic flowmeters for detecting the water flow in the cooling water return pipeline and the chilled water supply pipeline.

[0013] Preferably, the system further comprises electric regulating valves installed on the cooling water supply pipeline and the chilled water supply pipeline.

[0014] Preferably, one end of the chilled water shunt branch is connected with the chilled water supply pipeline, and the chilled water shunt branch is connected with the chilled water return pipeline through the butterfly valve.

[0015] Compared with the prior art, the water chilling unit has the following beneficial effects:

[0016] 1. The problem that the compressor is in an oil shortage state and thus stops running due to the low cooling water temperature and the low compression suction and discharge pressure difference in the transition season is effectively solved, the normal operation of the water chilling unit is ensured, the stability and reliability of the system are improved, the cooling water temperature is accurately adjusted through the control of the running frequency of the variable frequency water pump, the start and stop of the cooling tower fan and the opening degree of the electric regulating valve, the cooling water supply temperature entering the water chilling unit can be stabilized in the preset temperature range, and the operation condition of the water chilling unit is optimized.

[0017] 2. The cooling water shunt branch and the chilled water shunt branch are adopted, the shunt ratio is adjusted through the electric regulating valve, the water temperature can be flexibly adjusted, the adaptability and adjustment accuracy of the system are improved, the pressure sensors, the temperature sensors and the electromagnetic flowmeters are installed, the water pressure, the water temperature and the water flow in the pipeline can be monitored in real time, accurate data support is provided for the accurate control and fault diagnosis of the system, problems can be found and solved in time, the maintenance cost is reduced, the overall system structure is relatively simple, the control logic is clear, the system is easy to realize and operate, the installation and maintenance difficulty of the system is reduced, the practicability and operability of the system are improved, the operation efficiency of the water chilling unit under different seasons and operation conditions is improved, the energy consumption is reduced, the system has good energy-saving effect, and the operation cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0018] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, and can be implemented according to the content of the specification, the following is a preferred embodiment of the present application and the detailed description of the drawings as follows.

[0019] Figure 1 It is the overall structural diagram of the present application;

[0020] Figure 2 It is the use step schematic diagram of the present application.

[0021] Legend: 1, cooling water supply pipeline; 2, electric regulating valve; 3, cooling water shunt branch; 4, frequency conversion water pump; 5, cooling water return pipeline; 6, cooling tower; 7, user side equipment; 8, chilled water return pipeline; 9, electromagnetic flowmeter; 10, pressure sensor; 11, temperature sensor; 12, chilled water shunt branch; 13, butterfly valve; 14, chilled water supply pipeline. DETAILED DESCRIPTION

[0022] The embodiment of the present application provides a cooling water temperature adjusting system of water chiller, effectively solves the technical problem that in the case that the ambient temperature is low in the transition season, when the unit starts, the condensing temperature and the exhaust pressure are low due to the low cooling water temperature, and then the suction and exhaust pressure difference is less than the set value, and the oil supply is impossible, at this time, the bearing of the compressor is in the oil shortage state operation, if the suction and exhaust pressure difference does not reach the specified value within the set time, the compressor stops, and the normal operation of the refrigeration machine is affected.

[0023] As Figure 1As shown, the water temperature adjusting system of the water chilling unit comprises a cooling water supply pipeline 1 and a cooling water return pipeline 5, a chilled water supply pipeline 14 and a chilled water return pipeline 8, a variable frequency water pump 4 and a cooling tower 6. The cooling water supply pipeline 1 is used for supplying cooling water to the water chilling unit, the cooling water return pipeline 5 is used for supplying the cooling water, which has absorbed heat of refrigerant, back to the cooling tower 6, the chilled water supply pipeline 14 is used for supplying the cooling water, which has been cooled by the water chilling unit, to a user side equipment 7, the chilled water return pipeline 8 is used for returning the chilled water, which has been heat-exchanged with the user side equipment 7, to the water chilling unit to be frozen again, and the variable frequency water pump 4 is used for providing power to water flow. One end of the cooling water supply pipeline 1 is connected to a water outlet of the cooling tower 6 and connected to a water supply end of the water chilling unit through the variable frequency water pump 4, and two ends of the cooling water return pipeline 5 are connected to a water return end of the water chilling unit and a water inlet of the cooling tower 6 respectively. Two ends of the chilled water supply pipeline 14 are connected to the water supply end of the water chilling unit and the user side equipment 7 respectively, one end of the chilled water return pipeline 8 is connected to the user side equipment 7 and connected to the water return end of the water chilling unit through the variable frequency water pump 4. The water temperature adjusting system of the water chilling unit further comprises a cooling water shunt branch 3 and a chilled water shunt branch 12. The cooling water shunt branch 3 is used for reducing the flow to the water supply end of the water chilling unit, so as to increase the water temperature of the cooling water entering the water chilling unit, and the chilled water shunt branch 12 is used for increasing the flow to the chilled water return end of the water chilling unit, so as to increase the evaporation pressure and indirectly increase the water temperature of the cooling water entering the water chilling unit. One end of the cooling water shunt branch 3 is connected to the cooling water supply pipeline 1 and connected to the cooling water return pipeline 5 through a butterfly valve 13, and one end of the chilled water shunt branch 12 is connected to the chilled water supply pipeline 14 and connected to the chilled water return pipeline 8 through the butterfly valve 13.

[0024] In the embodiment, the cooling tower 6 is an induced-draft counterflow wet cooling tower, cooling water return enters water spraying filler from top to bottom, air goes up from bottom to top under the action of cooling fan, air and water directly contact to exchange heat, and the cooling efficiency is high and stable.

[0025] In the embodiment, the water temperature adjusting system of the water chilling unit further comprises a pressure sensor 10 and a temperature sensor 11 for detecting water pressure and water temperature in the cooling water supply pipeline 1 and the cooling water return pipeline 5, the chilled water supply pipeline 14 and the chilled water return pipeline 8.

[0026] In the embodiment, the water temperature adjusting system of the water chilling unit further comprises an electromagnetic flowmeter 9 for detecting water flow in the cooling water return pipeline 5 and the chilled water supply pipeline 14.

[0027] In the embodiment, the cooling water temperature adjusting system of the water chiller further comprises an electric regulating valve 2 installed on the cooling water supply pipeline 1 and the chilled water supply pipeline 14, which is used to adjust the shunt ratio between the cooling water supply pipeline 1 and the cooling water shunt branch 3 and between the chilled water return pipeline 8 and the chilled water shunt branch 12.

[0028] The control of the opening degree of the electric regulating valve 2 installed on the cooling water supply pipeline 1 and the chilled water supply pipeline 14 and the adjustment of the shunt ratio between the cooling water supply pipeline 1 and the cooling water shunt branch 3 and between the chilled water return pipeline 8 and the chilled water shunt branch 12 comprises:

[0029] The control of the electric regulating valve 2 installed on the cooling water supply pipeline 1 to reduce the opening degree and reduce the flow to the water chiller cooling water supply end; and the control of the electric regulating valve 2 installed on the chilled water supply pipeline 14 to increase the opening degree and increase the flow to the water chiller chilled water return end.

[0030] Figure 1 The four pipelines from left to right at the lowermost end of the adjusting system are: connected to the chilled water supply end of the water chiller, connected to the chilled water return end of the water chiller, connected to the cooling water supply end of the water chiller, and connected to the cooling water return end of the water chiller.

[0031] Working principle:

[0032] Step 1: system starts;

[0033] Step 2: the temperature sensor 11 obtains the cooling water temperature flowing to the water chiller supply end in the cooling water supply pipeline 1;

[0034] Step 3: when the supply water temperature is lower than the required preset cooling water temperature range, the frequency of the variable frequency water pump 4 on the cooling water supply pipeline 1 is reduced to reduce the flow, and if the supply water temperature is still lower than the required preset cooling water temperature range, Step 4 is performed, otherwise the process is ended;

[0035] Step 4: the cooling fan of the cooling tower 6 is controlled to stop running, and if the supply water temperature is still lower than the required preset cooling water temperature range, Step 5 is performed, otherwise the process is ended;

[0036] Step 5: the electric regulating valve 2 installed on the cooling water supply pipeline 1 and the chilled water supply pipeline 14 is controlled to adjust the opening degree and adjust the shunt ratio between the cooling water supply pipeline 1 and the cooling water shunt branch 3 and between the chilled water return pipeline 8 and the chilled water shunt branch 12.

[0037] Finally, it should be noted that: apparently, the above embodiments are merely examples for clearly illustrating the utility model, and are not limited to the implementation. For ordinary skilled in the art, on the basis of the above description, other different forms of changes or variations can be made. Here, it is not necessary and impossible to exhaust all the implementation. The obvious changes or variations derived from it are still within the protection scope of the utility model.

Claims

1. A chilled water chiller water temperature regulating system, comprising: The cooling water temperature adjusting system of the water chilling unit comprises a cooling water supply pipeline (1) and a cooling water return pipeline (5), a chilled water supply pipeline (14) and a chilled water return pipeline (8), a variable frequency water pump (4), a user-side device (7) and a cooling tower (6); One end of the cooling water supply pipeline (1) is connected to the water outlet of the cooling tower (6) and connected to the water supply end of the water chilling unit through the variable frequency water pump (4), and two ends of the cooling water return pipeline (5) are respectively connected to the water return end of the water chilling unit and the water inlet of the cooling tower (6); Two ends of the chilled water supply pipeline (14) are respectively connected to the water supply end of the water chilling unit and the user-side device (7), and one end of the chilled water return pipeline (8) is connected to the user-side device (7) and connected to the water return end of the water chilling unit through the variable frequency water pump (4); The cooling water temperature adjusting system of the water chilling unit further comprises a cooling water shunt branch (3), a chilled water supply pipeline (14), a butterfly valve (13) and a chilled water shunt branch (12), one end of the cooling water shunt branch (3) is connected to the cooling water supply pipeline (1) and connected to the cooling water return pipeline (5) through the butterfly valve (13).

2. A chilled water chiller water temperature regulating system as defined in claim 1 wherein: The cooling tower (6) has a cooling fan.

3. A chilled water chiller water temperature regulating system as recited in claim 2 wherein: It further comprises a pressure sensor (10) and a temperature sensor (11) for detecting the water pressure and water temperature in the cooling water supply pipeline (1), the cooling water return pipeline (5), the chilled water supply pipeline (14) and the chilled water return pipeline (8).

4. A chilled water chiller water temperature regulating system as recited in claim 3 wherein: It further comprises an electromagnetic flowmeter (9) for detecting the water flow in the cooling water return pipeline (5) and the chilled water supply pipeline (14).

5. A chilled water chiller water temperature regulating system as recited in claim 4, wherein: It further comprises an electric regulating valve (2) installed on the cooling water supply pipeline (1) and the chilled water supply pipeline (14).

6. A chilled water chiller water temperature regulating system as recited in claim 5, wherein: One end of the chilled water shunt branch (12) is connected to the chilled water supply pipeline (14) and connected to the chilled water return pipeline (8) through the butterfly valve (13).

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