CN210638329U - Injection system, oil return system of water chilling unit and water chilling unit - Google Patents
Injection system, oil return system of water chilling unit and water chilling unit Download PDFInfo
- Publication number
- CN210638329U CN210638329U CN201921185166.XU CN201921185166U CN210638329U CN 210638329 U CN210638329 U CN 210638329U CN 201921185166 U CN201921185166 U CN 201921185166U CN 210638329 U CN210638329 U CN 210638329U
- Authority
- CN
- China
- Prior art keywords
- oil
- compressor
- ejector
- branch
- outlet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The utility model provides an draw oil return system, cooling water set of penetrating system and cooling water set relates to oil return control technical field. Wherein draw and penetrate the system and include: the first ejector is provided with a first high-pressure inlet, a first mixing inlet and a first outlet, the first high-pressure inlet is used for introducing high-pressure gaseous refrigerants, and the first mixing inlet is used for introducing mixed liquid of oil and liquid refrigerants; the first outlet is communicated with the oil tank through a first branch, and a first electromagnetic valve is arranged on the first branch; the first outlet is communicated with an air suction port of the compressor through a second branch, and a second electromagnetic valve is arranged on the second branch. When the guide vane aperture is big, the impeller air-breathing capacity is strong, open through controlling first solenoid valve and make first branch road intercommunication, control the second solenoid valve and close and make the disconnection of second branch road for the oil that draws through first ejector directly gets into the oil tank, can not be taken away by the air current at the induction port of compressor, avoids the oil tank to lack oily phenomenon.
Description
Technical Field
The utility model discloses oil return control technical field particularly, relates to an injection system and cooling water set's oil return system, cooling water set.
Background
Chiller (or air conditioning) is a common refrigeration device that typically includes a centrifugal compressor. In the running process of the water chilling unit, because the rotating speed of the compressor is high, the exhaust gas volume is large, and the oil discharge volume is also large, a special oil return path is generally required to be arranged to recover the oil discharged by the compressor.
In the prior art, oil return is generally carried out through primary injection and secondary injection, the primary injection oil return is that high-pressure gaseous refrigerant is led out from a condenser and enters an injector, mixed liquid containing lubricating oil and liquid refrigerant is sucked out from an evaporator and mixed to enter a gas suction port of a compressor, and refrigerant gas at the gas suction port is compressed by the compressor. The oil at the air suction port is further recovered by secondary injection, and the lubricating oil deposited at the air suction port of the compressor is sucked out by the high-pressure gaseous refrigerant of the condenser through secondary injection by the secondary injection and mixed to enter the oil tank.
The centrifugal compressor often appears the low unusual problem of low oil level after sale at present, and one of its most important reason is because when the stator aperture is big, when the impeller suction capacity is strong, the one-level draws and penetrates the unable persistence of oil by the purification at the induction port, directly is taken away by the air current, can lead to the oil tank to lack the oil phenomenon for a long time.
SUMMERY OF THE UTILITY MODEL
For solving the technical problem that the one-level injection oil can't persist at the compressor induction port among the prior art, the utility model aims to provide an injection system and cooling water set's oil return system, cooling water set.
In a first aspect, the embodiment of the present invention provides an injection system, including: the first ejector is provided with a first high-pressure inlet, a first mixing inlet and a first outlet, the first high-pressure inlet is used for introducing high-pressure gaseous refrigerants, and the first mixing inlet is used for introducing mixed liquid of oil and liquid refrigerants; the first outlet is communicated with the oil tank through a first branch, and a first electromagnetic valve is arranged on the first branch; the first outlet is communicated with an air suction port of the compressor through a second branch, and a second electromagnetic valve is arranged on the second branch.
Further, in a preferred embodiment of the present invention, the method further includes: the second ejector is provided with a second high-pressure inlet, an oil suction port and a second outlet;
the second high-pressure inlet is communicated with a first exhaust port of the compressor, the oil suction port is communicated with an air suction port of the compressor, the second outlet is communicated with the oil tank through a pipeline, and a third electromagnetic valve is arranged on the pipeline.
In a second aspect, an embodiment of the present invention provides an oil return system for a water chiller, including: the injection system comprises a compressor, a condenser, an evaporator, an oil tank and any one of the injection systems;
the first ejector is communicated with the condenser through the first high-pressure inlet, the first ejector is communicated with the evaporator through the first mixing inlet, the first outlet of the first ejector is communicated with an air suction port of the compressor through the second branch, and the first outlet of the first ejector is communicated with the oil tank through the first branch.
Further, in a preferred embodiment of the present invention, the injection system further includes a second injector, and the second injector has a second high-pressure inlet, an oil suction port, and a second outlet; the second high pressure inlet is communicated with the first exhaust port of the compressor, and the oil suction port is communicated with the air suction port of the compressor.
Further, in a preferred embodiment of the present invention, a volute is disposed inside the compressor, and the first exhaust port is an exhaust port of the volute.
In a third aspect, an embodiment of the present invention provides a water chiller, including any one of the oil return systems of the water chiller.
Further, in a preferred embodiment of the present invention, the compressor has a second gas outlet, and the second gas outlet is communicated with the condenser.
Further, in a preferred embodiment of the present invention, the oil tank is communicated with the compressor through an oil pump.
The embodiment of the utility model provides a pair of draw oil return system, cooling water set of system and cooling water set draw, wherein draw and penetrate the system, the first outlet side of first ejector has set up two branches, and has all set up the solenoid valve on first branch road and the second branch road. When the stator aperture is big, the impeller air-breathing capacity is strong, can open to make first branch road intercommunication through controlling first solenoid valve to control the second solenoid valve and close and make the disconnection of second branch road, thereby make the oil that draws through first ejector directly get into the oil tank, do not pass through the induction port of compressor, just can not be taken away by the air current at the induction port of compressor yet, avoid the oil tank to lack oily phenomenon.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic view of an oil return system of a water chiller according to an embodiment of the present invention.
Reference numerals:
1. the compressor comprises a compressor 11, an air suction port 12, a first exhaust port 13, a second exhaust port 2, a condenser 3, an evaporator 4, an oil tank 5, a first ejector 51, a first high-pressure inlet 52, a first mixing inlet 53, a first outlet 6, a second ejector 61, a second high-pressure inlet 62, an oil suction port 63, a second outlet 7, a first electromagnetic valve 8, a second electromagnetic valve 9 and a third electromagnetic valve.
Detailed Description
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and that for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.
An embodiment of the utility model provides a cold water set, including compressor 1, condenser 2, evaporimeter 3, oil tank 4 and oil return system, 1 inside volutes and the stator of being provided with of compressor, compressor 1 has induction port 11, first exhaust port 12 and second gas vent 13, and wherein first exhaust port 12 indicates the gas vent of volute. A second exhaust port 13 of the compressor 1 is communicated with a refrigerant inlet of the condenser 2, and a refrigerant outlet of the condenser 2 is communicated with a refrigerant inlet of the evaporator 3; the oil tank 4 is communicated with the compressor 1 through an oil pump, the outlet of the oil tank 4 is communicated with the inlet of the oil pump, and the outlet of the oil pump is communicated with the oil inlet of the compressor 1; the oil pump pumps oil in the oil tank 4 into the compressor 1 for use by the compressor 1.
Wherein, the embodiment of the utility model provides an oil return system adopts and draws the system realization of penetrating.
As shown in fig. 1, an embodiment of the present invention provides an injection system, including: the first ejector 5 is provided with a first high-pressure inlet 51, a first mixing inlet 52 and a first outlet 53, wherein the first high-pressure inlet 51 is used for introducing high-pressure gaseous refrigerants, and the first mixing inlet 52 is used for introducing oil and liquid refrigerant mixed liquid; the first outlet 53 is communicated with the oil tank 4 through a first branch, and a first electromagnetic valve 7 is arranged on the first branch; the first outlet 53 is communicated with the suction port 11 of the compressor 1 through a second branch, and a second electromagnetic valve 8 is arranged on the second branch. Among the injection system, two branches are arranged on the first outlet 53 side of the first injector 5, and electromagnetic valves are arranged on the first branch and the second branch. When the stator aperture is big, the impeller air-breathing capacity is strong, can open to make first branch road intercommunication through controlling first solenoid valve 7 to control second solenoid valve 8 and close and make the disconnection of second branch road, thereby make the oil that draws through first ejector 5 directly get into oil tank 4, do not pass through air-suction port 11 of compressor 1, just can not be taken away by the air current at air-suction port 11 of compressor 1 yet, lead to the lack of oil phenomenon.
In the prior art, if the two stages of injection are connected in series and bypass the inlet of the compressor 1, although the problem of oil shortage of the oil tank 4 can be solved, when a water chilling unit runs under the condition of low load oil temperature, excessive refrigerant can be directly injected into the oil tank 4, so that the oil supply temperature is low, and the reliability of the unit is influenced. Therefore, how to grasp the balance between the oil temperature and the return oil is also a problem. The utility model relates to an in the embodiment, draw and penetrate the system and still include: a second eductor 6, the second eductor 6 having a second high pressure inlet 61, an oil suction port 62 and a second outlet 63; the second high-pressure inlet 61 is communicated with the first exhaust port 12 of the compressor 1, the oil suction port 62 is communicated with the air suction port 11 of the compressor 1, the second outlet 63 is communicated with the oil tank 4 through a pipeline, and the pipeline is provided with a third electromagnetic valve 9. The one-stage injection is still kept to enter at the air suction port 11 of the compressor 1, when the water chilling unit is low in low-load oil temperature, the series connection of the one-stage injection and the two-stage injection is achieved by closing the first electromagnetic valve 7 and opening the second electromagnetic valve 8 and the third electromagnetic valve 9, oil obtained by injection of the first injector 5 is sucked into the second injector 6 under the action of high-pressure refrigerants and then is transmitted into the oil tank 4, the oil supply temperature is effectively stabilized, and the phenomenon that a large amount of refrigerants are directly injected into the oil tank 4 under the condition that the oil temperature is not high per se, and the oil supply temperature is too low is avoided. The technical effect of preventing oil from being taken away by airflow can be achieved by adjusting the opening and closing of the first electromagnetic valve 7, the second electromagnetic valve 8 and the third electromagnetic valve 9; or under the condition of low load and low oil temperature, the problem of low oil supply temperature is solved.
As shown in fig. 1, the utility model provides a water chilling unit's oil return system, first ejector 5 passes through first high-pressure inlet 51 with condenser 2 intercommunication, first ejector 5 passes through first mixing inlet 52 with evaporimeter 3 intercommunication, first ejector 5 first export 53 pass through the second branch road with compressor 1's induction port 11 intercommunication, first ejector 5 first export 53 pass through first branch road and oil tank 4 intercommunication. In this embodiment, the ejector system further includes a second ejector 6, and the second ejector 6 has a second high-pressure inlet 61, an oil suction port 62, and a second outlet 63; the second high pressure inlet 61 communicates with the first exhaust port 12 of the compressor 1, and the oil suction port 62 communicates with the suction port 11 of the compressor 1. The oil return pipeline of the first-stage injection and the oil return pipeline of the second-stage injection are connected in series, and the technical effect of preventing oil from being taken away by airflow can be achieved through the arranged electromagnetic valve, the second electromagnetic valve 8 and the third electromagnetic valve 9; or under the condition of low load and low oil temperature, the problem of low oil supply temperature is solved.
In the prior art, a power source for secondary injection is high-pressure gas in the condenser 2, but the pressure of the condenser 2 is relatively small under low pressure difference or low-temperature working conditions, and injection oil return power is insufficient. Through the analysis, condenser 2 draws under low pressure difference or low temperature operating mode and penetrates oil return power not enough, is because the spiral case exhausts the pressure loss to between the condenser 2, consequently the utility model discloses an in the oil return system that provides, 1 inside spiral case that is provided with of compressor, first exhaust port 12 does the gas vent of spiral case. The power source of the secondary injection oil return is changed from the condenser 2 to the outlet of the volute of the compressor 1, the pressure at the exhaust port of the volute is more sufficient, the injection capacity is enhanced, and the oil return power of the secondary injection can be met; meanwhile, the pipeline from the condenser 2 to the second ejector 6 is removed, the pipeline is effectively saved, the exhaust port of the volute is closer to the second ejector 6, the process difficulty is reduced, and the problem of stress vibration caused by overlong horizontal pipelines is also solved.
Combine above-mentioned first ejector 5, second ejector 6, the second grade to draw the change of penetrating the power supply and the setting of above-mentioned three solenoid valve, the embodiment of the utility model provides a still provides a cooling water set's oil return system's control method, including following step:
for the frequency conversion centrifugal machine, the guide vanes are opened firstly when the frequency conversion centrifugal machine is loaded, and when the opening degree of the guide vanes reaches the maximum value, namely 100%, the frequency is increased; therefore, assuming that the guide vane opening degree is fully opened, a first frequency threshold value is set; the frequency of the frequency converter set has larger influence on the air suction capacity relative to the opening degree of the guide vane, and the first frequency threshold value is about 70% of the maximum frequency value;
detecting the actual frequency of the compressor 1;
when the actual opening value is fully opened, namely the opening of the guide vane is 100%, and the actual frequency is greater than or equal to the first frequency threshold value, the air suction capacity of the unit is strong, the rotating speed is high, and the heat generated by the bearing is transferred to lubricating oil, so that the oil temperature is high;
control first solenoid valve 7 and open, second solenoid valve 8 and third solenoid valve 9 are closed to make through the first mixed liquid of the drawing of first ejector 5 flows into oil tank 4, specific: the mixture of the liquid refrigerant and the oil in the evaporator 3 is ejected by the high-pressure gaseous refrigerant in the condenser 2, enters the first ejector 5, becomes a first mixed liquid, flows out, passes through the first electromagnetic valve 7 and is introduced into the oil tank 4; the oil is prevented from being taken away when the air suction capacity of the compressor 1 is strong, and the problem of high oil temperature under the condition of high load can be effectively solved.
Further, the method also comprises the following steps:
when the guide vanes of the variable frequency centrifuge are fully opened and the actual frequency is less than the first frequency threshold value, the air suction capacity of the compressor 1 is small, the rotating speed is low, and the heat quantity of lubricating oil supplied by relative heat exchange is small;
controlling the first electromagnetic valve 7 to be closed, and controlling the second electromagnetic valve 8 and the third electromagnetic valve 9 to be opened;
so that the first mixed liquid injected by the first injector 5 enters the air suction port 11 of the compressor 1 through the second electromagnetic valve 8; oil in the first mixed liquid enters the second ejector 6 through the oil suction port 62, the high-pressure gaseous refrigerant at the first exhaust port 12 of the compressor 1 enters the second ejector 6 through the second high-pressure inlet 61, and the second mixed liquid passing through the second ejector 6 enters the oil tank 4 through the third electromagnetic valve 9, specifically:
the liquid refrigerant and oil mixture in the evaporator 3 is ejected by the high-pressure gaseous refrigerant in the condenser 2, enters the first ejector 5 and then becomes a first mixed liquid to flow out, the first mixed liquid enters the air suction port 11 of the compressor 1 through the second electromagnetic valve 8, and at the moment, the refrigerant in the second mixed liquid is sucked into the compressor 1 to be compressed; the oil in the second mixed liquid is deposited at the inlet of the compressor 1, is sucked out by the high-pressure gaseous refrigerant from the first exhaust port 12 (the volute exhaust port) and flows out in the form of the second mixed liquid through the second ejector 6, and the second mixed liquid enters the oil tank 4 through the third electromagnetic valve 9; under the condition, the oil at the inlet of the compressor 1 can not be sucked away when the air suction capacity is weak, and the refrigerant entering the oil tank 4 is greatly reduced by injection, so that the oil supply temperature is kept stable under the condition that the low-load low-frequency original oil temperature cannot be very high, and the reliability of the unit is improved.
In the method, the first exhaust port 12 is an exhaust port of the volute, so that the original power source for secondary injection is changed from the condenser 2 to the volute exhaust part of the compressor 1, the pressure of the second injector 6 is enhanced, the pressure loss from the volute exhaust part of the compressor 1 to the condenser 2 through the exhaust pipe is reduced, compared with a pipeline for introducing the second injector 6 from the condenser 2, the pipeline is much shorter, and the process difficulty and the stress problem are reduced.
For a fixed frequency unit, the air suction capacity is adjusted only through the opening degree of the guide vane, meanwhile, when the opening degree of the guide vane is large, the air suction capacity is strong, meanwhile, high load does work, the exhaust temperature is high, the oil temperature is also high due to high current, namely, a guide vane opening threshold value is set, the guide vane is fully opened to be 100%, and the opening threshold value of the guide vane is about 45%.
When the actual guide vane aperture is greater than or equal to the aperture threshold value, adopt the series connection one second grade to draw and penetrate and bypass 1 mode of compressor and carry out the oil return: controlling the first electromagnetic valve 7 to be opened and the second electromagnetic valve 8 to be closed so as to enable the first mixed liquid injected by the first injector 5 to flow into the oil tank 4; specifically, a mixture of refrigerant and oil in the high-pressure gaseous refrigerant suction evaporator 3 led out from the condenser 2 is directly led to the oil tank through the first electromagnetic valve 7 (at the moment, the second electromagnetic valve 8 and the third electromagnetic valve 9 are closed) by the first mixed liquid led out from the first ejector 5, and secondary ejection is not needed.
When the actual guide vane opening is smaller than the opening threshold, a one-level two-level injection oil return mode is adopted: controlling the first electromagnetic valve 7 to be closed, the second electromagnetic valve 8 and the third electromagnetic valve 9 to be opened, leading out a mixture of refrigerant and oil in the high-pressure gaseous refrigerant suction evaporator 3 from the specific condenser 2, leading a first mixed solution which is injected by the first injector 5 to pass through the second electromagnetic valve 8 (at the moment, the first electromagnetic valve 7 is closed), and then leading the mixed solution to an air suction port 11 of the compressor 1 (a first-stage injection process); the liquid refrigerant at the air suction port 11 is flashed into a gas state and sucked by the compressor 1, the lubricating oil is left at the air suction port 11 of the compressor 1, the second ejector 6 ejects the high-pressure gas refrigerant from the first exhaust port 12 (volute exhaust port), sucks the lubricating oil left at the air suction port 11 of the compressor 1 (the lubricating oil enters the second ejector 6 through the oil suction port 62), and finally reaches the oil tank 4 through the third electromagnetic valve 9 (a secondary ejection process).
In the description of the present invention, it is to be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. This is merely for convenience in describing the invention and to simplify the description and is not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation and is therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. The utility model provides an draw and penetrate system which characterized in that includes: the first ejector (5), the first ejector (5) is provided with a first high-pressure inlet (51), a first mixing inlet (52) and a first outlet (53), the first high-pressure inlet (51) is used for introducing high-pressure gaseous refrigerant, and the first mixing inlet (52) is used for introducing a mixed liquid of oil and liquid refrigerant; the first outlet (53) is communicated with the oil tank (4) through a first branch, and a first electromagnetic valve (7) is arranged on the first branch; the first outlet (53) is communicated with a suction port (11) of the compressor (1) through a second branch, and a second electromagnetic valve (8) is arranged on the second branch.
2. The induction system of claim 1, further comprising: a second eductor (6), the second eductor (6) having a second high pressure inlet (61), an oil suction port (62) and a second outlet (63);
the second high-pressure inlet (61) is communicated with a first exhaust port (12) of the compressor (1), the oil suction port (62) is communicated with an air suction port (11) of the compressor (1), the second outlet (63) is communicated with the oil tank (4) through a pipeline, and a third electromagnetic valve (9) is arranged on the pipeline.
3. An oil return system of a water chilling unit, comprising: -a compressor (1), a condenser (2), an evaporator (3), an oil tank (4) and an ejector system according to any one of claims 1-2;
first ejector (5) through first high pressure entry (51) with condenser (2) intercommunication, first ejector (5) through first mixed entry (52) with evaporimeter (3) intercommunication, first ejector (5) first export (53) pass through the second branch road with induction port (11) intercommunication of compressor (1), first ejector (5) first export (53) pass through first branch road and oil tank (4) intercommunication.
4. The oil return system of the water chilling unit according to claim 3, wherein the ejector system further comprises a second ejector (6), the second ejector (6) having a second high pressure inlet (61), an oil suction port (62) and a second outlet (63); the second high pressure inlet (61) communicates with the first exhaust port (12) of the compressor (1), and the oil suction port (62) communicates with the suction port (11) of the compressor (1).
5. The oil return system of a water chilling unit according to claim 4, wherein a volute is arranged inside the compressor (1), and the first exhaust port (12) is an exhaust port of the volute.
6. A chiller including the oil return system of the chiller according to any one of claims 3 to 5.
7. Water chilling unit according to claim 6, characterized in that the compressor (1) has a second discharge (13), the second discharge (13) communicating with the condenser (2).
8. Water chilling unit according to claim 7, characterized in that the oil tank (4) communicates with the compressor (1) by means of an oil pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921185166.XU CN210638329U (en) | 2019-07-25 | 2019-07-25 | Injection system, oil return system of water chilling unit and water chilling unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921185166.XU CN210638329U (en) | 2019-07-25 | 2019-07-25 | Injection system, oil return system of water chilling unit and water chilling unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210638329U true CN210638329U (en) | 2020-05-29 |
Family
ID=70796029
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921185166.XU Active CN210638329U (en) | 2019-07-25 | 2019-07-25 | Injection system, oil return system of water chilling unit and water chilling unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210638329U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110530062A (en) * | 2019-07-25 | 2019-12-03 | 珠海格力电器股份有限公司 | Ejection system and the oil return system of water cooler, control method, water cooler |
-
2019
- 2019-07-25 CN CN201921185166.XU patent/CN210638329U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110530062A (en) * | 2019-07-25 | 2019-12-03 | 珠海格力电器股份有限公司 | Ejection system and the oil return system of water cooler, control method, water cooler |
| CN110530062B (en) * | 2019-07-25 | 2024-02-09 | 珠海格力电器股份有限公司 | Oil return system of injection system and water chilling unit, control method and water chilling unit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1676616B1 (en) | Method and device for introducing an air-entrained liquid flow to a centrifugal pump | |
| CN104296421B (en) | Air conditioner and oil return control method thereof | |
| CN109682106B (en) | Refrigerant circulation system for slowing down surge of compressor, control method thereof and air conditioner | |
| CN111623558B (en) | Air conditioning system | |
| CN111928507B (en) | Refrigerant circulation system, control method and air conditioning unit | |
| CN110530062B (en) | Oil return system of injection system and water chilling unit, control method and water chilling unit | |
| CN210638329U (en) | Injection system, oil return system of water chilling unit and water chilling unit | |
| CN212657900U (en) | Refrigerant circulation system and air conditioning unit | |
| CN209783030U (en) | Water-cooling flooded double-circulation parallel system | |
| CN109945540B (en) | Water-cooling full-liquid type double-circulation parallel system and oil return balancing method thereof | |
| CN204665752U (en) | Air-conditioning system | |
| CN214949922U (en) | Oil supply system of low-ring-temperature refrigerating unit | |
| CN217110102U (en) | Air-conditioning refrigeration system | |
| CN213578185U (en) | Refrigeration system and unit | |
| CN114198922B (en) | Liquid supply system of compressor | |
| CN105066533A (en) | Flash type oil purifying plant for centrifugal chiller | |
| CN115492787A (en) | Anti-surge control method of series centrifugal compressor unit and air conditioning equipment | |
| CN111928547A (en) | Oil separator, oil return system and air conditioning system | |
| CN113465231A (en) | Oil separator, oil return system and refrigerating system | |
| CN203298526U (en) | Oil returning and cooling dual-purpose device for refrigerating unit | |
| JP2014190627A (en) | Turbo refrigerator | |
| CN209744039U (en) | Compressor system for compressing nitrogen and oxygen | |
| CN111023608A (en) | Refrigerating unit with low energy consumption, high efficiency and stability and capable of preventing surge | |
| CN113091172A (en) | Non-condensable gas discharging device of air conditioning system and control method | |
| CN111928548A (en) | Gas-liquid separator, oil return system and air conditioning system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |