CN207471844U - A kind of oil return apparatus of refrigeration system - Google Patents
A kind of oil return apparatus of refrigeration system Download PDFInfo
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- CN207471844U CN207471844U CN201721350119.7U CN201721350119U CN207471844U CN 207471844 U CN207471844 U CN 207471844U CN 201721350119 U CN201721350119 U CN 201721350119U CN 207471844 U CN207471844 U CN 207471844U
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- oil return
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- pressure transmitter
- trapped fuel
- refrigeration system
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Abstract
The utility model discloses a kind of oil return apparatus of refrigeration system, and including sequentially connected evaporator, trapped fuel is curved, rises standpipe, horizontal transverse-pipe and gas-liquid separator.Secondary oil return mechanism is further included, which includes first pressure transmitter, second pressure transmitter, hot gas jet pipe, solenoid valve and electric control unit；The first pressure transmitter is arranged on the pipeline that gas-liquid separator is connect with compressor, the second pressure transmitter is arranged on evaporator and the pipeline of the curved connection of trapped fuel, one end of the hot gas jet pipe is connected with compressor high-pressure exhaust, its other end is connected with the curved close standpipe side that rises of trapped fuel, which is arranged on hot gas jet pipe；The electric control unit is used to be opened and closed according to the monitoring duty control solenoid valve of first pressure transmitter and second pressure transmitter.The utility model fundamentally solves refrigeration system problem of oil return, simple in structure, safe and reliable, high degree of automation caused by lubricating oil obstruction under limit cold operation operating mode.
Description
Technical field
The utility model is related to technical field of refrigerating devices, more particularly to a kind of oil return apparatus of refrigeration system.
Background technology
Vacuum freeze drier is also referred to as freeze dryer, commonly used in the drying of sterile preparation similar drug or biological agent.Medicine
The freezing dry process of product is commonly referred to as lyophilized, and the drying stage in freeze-drying process usually contains the liter carried out under vacuum conditions
Magnificent drying and desorbing and drying remove the moisture or organic solvent in drug by lyophilization and desorbing and drying, and by moisture or
Organic solvent freezes or is condensate on the coil pipe inside the cold-trap of freeze dryer, and the coil pipe is exactly the refrigeration system of freeze dryer cold-trap
The evaporator of system.The water vapour or organic solvent steam that drying process generates freeze on coil pipe or condense and discharge heat, institute
Release heat is absorbed and is taken away by the refrigeration working medium inside coil pipe.
The refrigeration system generally use of freeze dryer is using freon as the steam compression type refrigeration circulatory system of refrigeration working medium, institute
The cycle that the refrigeration working medium in system is carried out continuously compression, condensation, throttling, evaporation under the promotion of compressor is stated, it is cold so as to make
The coil temperature of trap is reduced to the required degree of freeze-drying process, meanwhile, the compressor for also having certain content in the system moistens
Lubricating oil fusion participates in cycle in refrigeration working medium.With the reduction of coil temperature, the evaporation capacity and flow velocity of refrigeration working medium in coil pipe
Also it is reducing, merging the lubricating oil in refrigeration working medium will detach, and with liquid aggregation in coils.If in coil pipe
Liquid lubricant cannot return to compressor in time, then compressor can break down when lacking lubricating oil, so, actually make
With the engineering field of freeze dryer, for the timely oil return of compressor and operational safety, with reference to shown in attached drawing 1, usually it is in refrigeration
It is provided with that interconnected trapped fuel is curved 2, rises standpipe 3, horizontal transverse-pipe 4 and gas-liquid separation between the evaporator 1 and compressor of system
Device 5.The evaporator 1 is just mounted in the coil pipe in cold-trap 101, and the liquid lubricant in the evaporator 1 flows under the effect of gravity
To trapped fuel curved 2, when trapped fuel curved 2 is blocked by lubricating oil, lubricating oil is forced past rising standpipe under the action of front and rear pressure difference
3 enter horizontal transverse-pipe 5 and flow to compressor, so as to complete the oil return of compressor.
But in the parsing-desiccation stage of drug freeze-drying process, with the reduction of drug moisture, the freezing of coil pipe is born
Lotus is also constantly being reduced, and coil temperature is also constantly dropping to subzero 60 DEG C hereinafter, simultaneously gradually to subzero less than 75 DEG C of the limit
Low temperature approaches, and lower temperature makes oil body increase and flow resistance becomes larger, when trapped fuel is curved to be blocked by lubricating oil, by
It is very low in the evaporating pressure of refrigeration working medium in coil pipe, it will usually to reach 0.2bar hereinafter, the front and rear pressure difference of lubricating oil is insufficient at this time
So that lubricating oil crosses rising standpipe, and it is curved with rising the phenomenon that standpipe is blocked by lubricating oil so as to which trapped fuel have occurred, at this point, refrigeration
The vaporization cycle of working medium is also ended, and the surface temperature of coil pipe significantly increases immediately.Only when coil temperature makes inside coil pipe
When pressure rise is to the flow resistance for overcoming lubricating oil enough, lubricating oil can just cross rising standpipe, and refrigeration working medium could restore
Vaporization cycle.But coil temperature is reduced near limit low temperature by refrigeration cycle again quickly, trapped fuel is curved with rising standpipe again again
It is secondary to be blocked, the lasting fluctuation increased with reducing occurs, and maximum fluctuation amplitude can reach 15 DEG C of left sides so as to cause coil temperature
It is right.
Coil temperature increases the fluctuation with reducing, and not only influences the fortune of safe and healthy and equipment of the drug in freeze-drying process
Row safety, moreover, having an effect on the test and judgement for the vacuum system leak rate that freeze dryer carries out in the unloaded state.First, coil pipe
The environmental pressure that temperature fluctuation can cause drug to be dried fluctuates therewith, particularly the later stage in the parsing-desiccation stage, due to drug
Environment vacuum degree it is higher, the pressure oscillation under high vacuum state can increase gaseous molecular inside cold-trap inversely into being used as medicine
The probability of product, so as to increase the contaminated risk of drug.Second, coil temperature fluctuation is curved with rising in standpipe derived from trapped fuel
Lubricating oil blocks, and the vaporization cycle that the obstruction also results in refrigeration working medium is ended, so as to cause unevaporated liquid system
Cold working medium is largely accumulated inside coil pipe, and when the pipeline dredging of obstruction, a large amount of liquid refrigeration working medium can moment with lubricating oil
It crosses and rises standpipe and flow to compressor；Although the refrigeration system of freeze dryer is generally configured with preventing the gas-liquid separator of liquid hammer,
But due to limited volume of the gas-liquid separator on engineer application, liquid hammer hidden danger still cannot be eliminated, it is even more impossible to avoid compressor
The longtime running under Wet Compression and destroy refrigeration system.Third, the airtight performance of freeze dryer vacuum system directly determine
Drug whether there is pollution risk, judge whether airtight performance is qualified, generally use coil pipe is examined under limit cold operation operating mode
The method for surveying freeze dryer vacuum system leak rate, fluctuation of the coil temperature under limit cold operation operating mode can cause vacuum system
Pressure oscillation, thus influence vacuum system leak rate test number authenticity, this normally results in freeze dryer because that can not judge
Whether airtight performance is qualified and cannot be used for pharmaceutical production.
At present, freeze dryer manufacturer there is no effective solution for temperature fluctuation of the coil pipe under limit cold operation operating mode
Certainly method.In order to avoid the harmful effect that coil temperature fluctuation generates, the method that freeze dryer manufacturer generally uses now has
Two, first, the refrigerating medium of silicone oil is used to freeze for coil pipe, second is that limitation rises the length dimension of standpipe, it is high with oil return is reduced
It spends to reduce the return pressure inside coil pipe, so as to reduce the fluctuating range of coil temperature.First method, in increasing
Between exchange heat link, the ability of coil pipe limit low temperature and fast cooling has apparent deficiency, meanwhile, the hot standby increase of intermediate heat transfer
Freeze dryer price is caused to increase considerably, thus use scope is limited.Second method, although disclosure satisfy that a part of pharmaceutical factory
The demand of quotient still, is restricted due to rising riser length, thus cannot meet manufacturer of drugs and dynamic in production environment is set
The standby demand that multi-zone supervision is carried out with static equipment；Meanwhile also without eliminating, trapped fuel is curved to be lubricated second method with rising in standpipe
The phenomenon that oil obstruction, coil temperature still fluctuates, and only fluctuating range reduces, and drug is safe and healthy hidden with equipment operational safety
Trouble still has, thus can not meet the requirements at the higher level that manufacturer of drugs proposes limitation coil temperature fluctuation.
It can be seen that the oil return apparatus of above-mentioned existing refrigeration system is upper with using in structure, method, it is clear that there are still have
Inconvenient and defect, and be urgently further improved.A kind of oil return apparatus of new refrigeration system how is founded, makes its solution
The refrigeration system reflux problem that lubricating oil blocks under limit worst cold case, becoming current industry pole needs improved target.
Utility model content
The technical problem to be solved by the present invention is to provide a kind of oil return apparatus of refrigeration system, it is made to solve refrigeration system
The system reflux problem that lubricating oil blocks under limit worst cold case, so as to overcome the shortcomings of existing refrigeration system oil return apparatus.
In order to solve the above technical problems, the utility model provides a kind of oil return apparatus of refrigeration system, the oil return apparatus
Including sequentially connected evaporator, trapped fuel is curved, rises standpipe, horizontal transverse-pipe and gas-liquid separator, and the entrance of the evaporator is used
It is connected in the throttling set outlet with the refrigeration system, the exhaust outlet of the gas-liquid separator is used for and the refrigeration system
Compressor low pressure air suction mouth be connected, the oil return apparatus further includes secondary oil return mechanism, and the pair oil return mechanism includes the first pressure
Power transmitter, second pressure transmitter, hot gas jet pipe, solenoid valve and electric control unit；
The first pressure transmitter is arranged on the pipeline that the gas-liquid separator is connect with compressor, second pressure
Power transmitter is arranged on the evaporator and the pipeline of the curved connection of trapped fuel, one end and the compressor of the hot gas jet pipe
High-pressure exhaust is connected, and the other end of the hot gas jet pipe is connected with the curved close rising standpipe side of the trapped fuel, the electricity
Magnet valve is arranged on the hot gas jet pipe；
The electric control unit is connected with the first pressure transmitter, second pressure transmitter and solenoid valve, is used for
The keying of the solenoid valve is controlled according to the monitor value of the first pressure transmitter and second pressure transmitter.
As a kind of improvement of the utility model, port direction and institute with the hot gas jet pipe of the curved connection of the trapped fuel
It is identical to state flowing to for the curved middle refrigeration working medium of trapped fuel.
It is further improved, the trapped fuel is curved to use U-shaped structure.
It is further improved, is inserted into the port of the hot gas jet pipe of the curved connection of the trapped fuel from the curved bottom of the trapped fuel,
And the hot gas spout port is higher than the peak of cross section where the U-shaped structure minimum point.
It is further improved, the evaporator uses shell-and-tube, brazing-sheet type or spiral plate type structure.
After such design, the utility model has at least the following advantages：
The utility model sets secondary reflux mechanism, makes it in the reflux by being improved to existing reflux
Reflux problem caused by lubricating oil obstruction is solved during in limit cold operation, and pass through setting electric control unit, it is right in real time
First pressure transmitter and the pressure monitoring value of second pressure transmitter are analyzed, and realize that automatic decision trapped fuel is curved and it is vertical to rise
Whether pipe is blocked, and solenoid valve is automatically turned on or closed with this, realizes the elimination of lubricating oil obstruction.The utility model flows back
Device is suitable for producing freeze dryer used in drug and biological agent and the deep cooling unit to cool down to refrigerating medium.
The utility model fundamentally solves the refrigeration system of freeze dryer and the deep cooling unit that cools down to refrigerating medium is in pole
Limit the problem of oil return under cold operation operating mode, have the characteristics that simple in structure, method reliably, it is high degree of automation, safe to use,
Requirements at the higher level of the manufacturer of drugs to technological equipment can not only be met, but also manufacturer of drugs can be met to still in the jelly of military service
The requirement that dry machine and deep cooling unit undergo technological transformation.
Description of the drawings
Above-mentioned is only the general introduction of technical solutions of the utility model, in order to better understand the technology hand of the utility model
Section, below in conjunction with attached drawing, the utility model is described in further detail with specific embodiment.
Fig. 1 is the oil return apparatus schematic diagram of refrigeration system in the prior art；
Fig. 2 is the oil return apparatus structure diagram of the utility model refrigeration system；
Wherein：1- evaporators, 2- trapped fuel is curved, and 3- rises standpipe, 4- horizontal transverse-pipes, 5- gas-liquid separators, 6- first pressures
Transmitter, 7- second pressure transmitters, 8- hot gas jet pipes, 9- solenoid valves, the cold-trap of 101- freeze dryers, 201- connection refrigeration systems
The outlet of throttling set, the low pressure air suction mouth of 202- connection refrigeration system compressors, the compressor of 203- connection refrigeration systems
High-pressure exhaust.
Specific embodiment
The utility model is described further in the following with reference to the drawings and specific embodiments, however the embodiment described is not
It should be construed in a limiting sense.
For the ease of understanding vapour compression refrigeration system existing problem of oil return, the present embodiment in limit cold operation
By taking the refrigeration system of vacuum freeze drier as an example, it is specifically described technical solutions of the utility model.
With reference to shown in attached drawing 2, the oil return apparatus of the present embodiment refrigeration system is curved including sequentially connected evaporator 1, trapped fuel
2nd, rise standpipe 3, horizontal transverse-pipe 4 and gas-liquid separator 5, the entrance of the evaporator 1 is for the throttling set with the refrigeration system
Outlet 201 is connected, and the exhaust outlet of the gas-liquid separator 5 is used to be connected with the compressor low pressure air suction mouth 202 of the refrigeration system.
In normal conditions, internal refrigeration working medium is carried out continuously compression, condensation, section to the oil return apparatus under the promotion of compressor
Stream, evaporation, reflux, form circulating for refrigeration working medium.
The reflux problem occurred under limit worst cold case to solve refrigeration system, the oil return apparatus further include secondary oil return machine
Structure, the pair oil return mechanism include first pressure transmitter 6, second pressure transmitter 7, hot gas jet pipe 8, solenoid valve 9 and electric-controlled
Unit processed.
The first pressure transmitter 6 is arranged on the pipeline that the gas-liquid separator 5 is connect with compressor, for monitoring in real time
And acquire the pressure value of the gas-liquid separator 5 and compressor connecting line.
The second pressure transmitter 7 is arranged on the pipeline that the evaporator 1 is connect with trapped fuel curved 2, for monitoring in real time simultaneously
Acquire the pressure value of the evaporator 1 and curved 2 connecting line of trapped fuel.
One end of the hot gas jet pipe 8 is connected with the high-pressure exhaust 203 of the compressor, the other end of the hot gas jet pipe 8 with
The trapped fuel curved 2 is connected close to 3 side of rising standpipe.It is more excellent to be set as：The port of the hot gas jet pipe 8 being connect with the trapped fuel curved 2
Towards in the trapped fuel curved 2 refrigeration working medium flow to it is identical.It is convenient for freezing from the high temperature that compressor is discharged and high-pressure gaseous in this way
Working medium avoids refrigeration working medium reflux along the trapped fuel curved 2 and the sequential flowing of rising standpipe 3.
Shell-and-tube, brazing-sheet type or spiral plate type structure can be used in the evaporator 1 in the present embodiment, and the trapped fuel curved 2 uses U
Type structure, the entrance of the U-shaped structure are connected with 1 bottom end outlet of evaporator.The hot gas jet pipe 8 being connect with the trapped fuel curved 2
Port is inserted into from curved 2 bottom of the trapped fuel, and 8 port of hot gas jet pipe is higher than the highest of cross section where the U-shaped structure minimum point
Point.More ensure that the port of the hot gas jet pipe 8 towards flowing to identical with refrigeration working medium in the trapped fuel curved 2, further avoids in this way
Refrigeration working medium reflux.
The solenoid valve 9 is arranged on the hot gas jet pipe 8, for the high temperature of compressor to be controlled to be passed through with high-pressure gaseous refrigeration working medium
It overheats gas blowout pipe 8 and enters trapped fuel curved 2, obstruction lubricating oil is heated and pressurizeed in realizing curved 2 to trapped fuel.
The electric control unit is connected with the first pressure transmitter 6, second pressure transmitter 7 and solenoid valve 9, for connecing
The pressure monitoring value that the first pressure transmitter 6 and second pressure transmitter 7 acquire is received, and passes through the analysis and Control solenoid valve 9
Keying.
The secondary oil return mechanism of above-mentioned refrigeration system is the supplement to existing refrigeration system reflux, for solving existing system
Cooling system reflux problem, specific oil return side of the pair oil return mechanism caused by existing lubricating oil obstruction in limit cold operation
Method is：
The electric control unit real-time reception is acquired and is sent by the first pressure transmitter 6 and second pressure transmitter 7
Pressure monitoring value, and the pressure monitoring value is analyzed.It is analyzed as follows：
If the pressure monitoring value of the first pressure transmitter 6 be less than the first preset value, such as 0.1bar, meanwhile, this second pressure
The pressure monitoring value of power transmitter 7 and the difference of the pressure monitoring value of the first pressure transmitter 6 are more than the second preset value, such as
0.1bar shows the trapped fuel curved 2 and rises standpipe 3 clogged conditions occur, and the electric control unit controls the solenoid valve 9 to open at this time
It opening, then the high temperature of the compressor enters the trapped fuel curved 2 by the hot gas jet pipe 8 with high-pressure gaseous refrigeration working medium and rises standpipe 3,
Obstruction lubricating oil is heated and pressurizeed in realizing curved 2 to trapped fuel, reduces lubricating oil viscosity and obtain to cross to rise the dynamic of standpipe 3
Power and return to compressor, achieve the purpose that restore in time refrigeration system oil return cycle.
If the pressure monitoring value of the first pressure transmitter 6 is more than third preset value, such as 0.25bar shows the trapped fuel curved 2
It flows back normal with rising standpipe 3 or does not occur clogged conditions, the electric control unit controls the solenoid valve 9 to close at this time.
The oil return principle of the oil return apparatus of the utility model refrigeration system is：It is curved with rising standpipe in the trapped fuel of refrigeration system
When lubricating oil obstruction occurs, it is curved that trapped fuel is passed directly into using the gaseous refrigerant working medium of the high temperature and high pressure that generate compressor operating
With rising in standpipe, the lubricating oil blocked is heated and be pressurizeed, lubricating oil viscosity is made to reduce and be crossed
It rises the power of standpipe and returns to compressor, achieve the purpose that restore refrigeration system oil return cycle in time.
The above descriptions are merely preferred embodiments of the present invention, and not the utility model is made in any form
Limitation, those skilled in the art make a little simple modification, equivalent variations or modification using the technology contents of the disclosure above,
It falls within the protection scope of the present utility model.
Claims (5)
1. a kind of oil return apparatus of refrigeration system, the oil return apparatus is including sequentially connected evaporator, trapped fuel is curved, rising is vertical
Pipe, horizontal transverse-pipe and gas-liquid separator, the entrance of the evaporator is for the throttling set outlet phase with the refrigeration system
Even, the exhaust outlet of the gas-liquid separator is used to be connected with the compressor low pressure air suction mouth of the refrigeration system, which is characterized in that
The oil return apparatus further includes secondary oil return mechanism, the pair oil return mechanism include first pressure transmitter, second pressure transmitter,
Hot gas jet pipe, solenoid valve and electric control unit；
The first pressure transmitter is arranged on the pipeline that the gas-liquid separator is connect with compressor, and the second pressure becomes
Device is sent to be arranged on the evaporator and the pipeline of the curved connection of trapped fuel, one end of the hot gas jet pipe and the high pressure of the compressor
Exhaust outlet is connected, and the other end of the hot gas jet pipe is connected with the curved close rising standpipe side of the trapped fuel, the solenoid valve
It is arranged on the hot gas jet pipe；
The electric control unit is connected with the first pressure transmitter, second pressure transmitter and solenoid valve, for basis
The monitor value of the first pressure transmitter and second pressure transmitter controls the keying of the solenoid valve.
2. the oil return apparatus of refrigeration system according to claim 1, which is characterized in that described in the curved connection of the trapped fuel
The port direction of hot gas jet pipe is identical with flowing to for the curved middle refrigeration working medium of the trapped fuel.
3. the oil return apparatus of refrigeration system according to claim 1, which is characterized in that the trapped fuel is curved to use U-shaped structure.
4. the oil return apparatus of refrigeration system according to claim 3, which is characterized in that described in the curved connection of the trapped fuel
The port of hot gas jet pipe is inserted into from the curved bottom of the trapped fuel, and the hot gas spout port is higher than the U-shaped structure minimum point institute
Peak in cross section.
5. the oil return apparatus of refrigeration system according to claim 1, which is characterized in that the evaporator using shell-and-tube,
Brazing-sheet type or spiral plate type structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721350119.7U CN207471844U (en) | 2017-10-18 | 2017-10-18 | A kind of oil return apparatus of refrigeration system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721350119.7U CN207471844U (en) | 2017-10-18 | 2017-10-18 | A kind of oil return apparatus of refrigeration system |
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| Publication Number | Publication Date |
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| CN207471844U true CN207471844U (en) | 2018-06-08 |
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| CN201721350119.7U Active CN207471844U (en) | 2017-10-18 | 2017-10-18 | A kind of oil return apparatus of refrigeration system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107560238A (en) * | 2017-10-18 | 2018-01-09 | 伊马莱富（北京）制药系统有限公司 | The oil return apparatus and oil return method of a kind of refrigeration system |
-
2017
- 2017-10-18 CN CN201721350119.7U patent/CN207471844U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107560238A (en) * | 2017-10-18 | 2018-01-09 | 伊马莱富（北京）制药系统有限公司 | The oil return apparatus and oil return method of a kind of refrigeration system |
| CN107560238B (en) * | 2017-10-18 | 2023-07-04 | 伊马莱富（北京）制药系统有限公司 | Oil return device and oil return method of refrigeration system |
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