CN111174454A - Ultra-low temperature water source overlapping large refrigeration equipment - Google Patents
Ultra-low temperature water source overlapping large refrigeration equipment Download PDFInfo
- Publication number
- CN111174454A CN111174454A CN201910846371.4A CN201910846371A CN111174454A CN 111174454 A CN111174454 A CN 111174454A CN 201910846371 A CN201910846371 A CN 201910846371A CN 111174454 A CN111174454 A CN 111174454A
- Authority
- CN
- China
- Prior art keywords
- temperature
- low
- pipeline
- input end
- screw compressor
- 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.)
- Pending
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B7/00—Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/40—Fluid line arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
- F25B43/003—Filters
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
Abstract
The invention discloses an ultra-low temperature water source overlapping large-scale refrigeration device, which comprises a high-temperature unit, a low-temperature unit and a cooling tower 3, wherein the high-temperature unit comprises a high-temperature screw compressor 1, a high-temperature oil separator 2, a water-cooled condenser 4, a high-temperature liquid storage tank 5, an economizer 6, a condensing evaporator 7 and the like, the low-temperature unit comprises a low-temperature screw compressor 33, a water-cooled cooler 35, a low-temperature oil separator 36, a low-temperature evaporator 7, a low-temperature heat regenerator 34, a low-temperature stage expansion container 37 and the like, and the low-temperature unit is remotely controlled by a. The invention provides an ultralow temperature working condition environment (-45-55 ℃) for inspecting the performance of produced mechanical and electrical products and equipment, and realizes the places of ultralow temperature working conditions which are difficult to reach by common refrigeration equipment.
Description
Technical Field
The invention relates to the field of cascade refrigeration equipment, in particular to ultra-low temperature water source cascade large refrigeration equipment.
Background
At present, mechanical or electronic products need to be operated and tested under an ultralow temperature working condition (-45 ℃ to-55 ℃) to test the performance and reliability of the mechanical or electronic products, so that refrigeration equipment is needed to prepare the ultralow temperature working condition (-45 ℃ to-55 ℃), and the ordinary air-conditioning refrigeration equipment is difficult to meet the requirement of the ultralow temperature refrigeration environment.
The invention aims to provide an ultra-low temperature water source overlapping large refrigeration device which can provide a large-range ultra-low temperature working condition environment under a normal temperature environment so as to solve the problem that the common air-conditioning refrigeration device in the prior art is difficult to realize ultra-low temperature refrigeration.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the utility model provides an ultra-low temperature water source overlapping large-scale refrigeration plant which characterized in that: including high temperature unit, cryogenic unit, cooling tower, wherein: the high-temperature unit comprises a high-temperature screw compressor 1, a high-temperature oil separator 2, a water-cooled condenser 4, a high-temperature liquid storage tank 5, an economizer 6 and a condensing evaporator 7, wherein the output end of the high-temperature screw compressor is connected with the input end of the high-temperature oil separator through a pipeline, the output end of the high-temperature oil separator 2 is connected with the input end of a high-temperature area in the water-cooled condenser 4 through a pipeline, the oil return end of the high-temperature oil separator 2 is connected with the oil return input end of the high-temperature screw compressor 1 through a pipeline, the output end of the high-temperature area in the water-cooled condenser 4 is connected with the input end of the high-temperature liquid storage tank 5 through a pipeline with a filter, the cooling tower 3 is respectively connected with the input end and the output end of a low-temperature area in the, the output end of a liquid phase region in the economizer 6 is connected with the input end of a high-temperature region in the condensation evaporator 7 through a pipeline with a liquid path electromagnetic valve 20 and an electronic expansion valve 32, a bypass pipeline with an enthalpy-increasing electromagnetic valve 25 and an enthalpy-increasing expansion valve 26 is communicated to the input end of the liquid phase region in the economizer 6 between the filter 22 and the economizer, the output end of the liquid phase region in the economizer 6 is connected with the enthalpy-increasing input end of the high-temperature screw compressor 1 through a pipeline, and the output end of the high-temperature region in the condensation evaporator 7 is connected with the return air input end of the high-temperature screw compressor 1 through a pipeline;
the low-temperature unit comprises a low-temperature screw compressor 33, a water-cooled cooler 35, a low-temperature oil separator 36, a low-temperature condenser 7, a low-temperature heat regenerator 34, evaporation fans 64/67, two groups of low-temperature evaporators 62/65, a low-temperature stage expansion container 37, an exhaust pressure controller 60, suction pressure controllers 57 and 59 and system pressure controllers 56 and 58, wherein the output end of the low-temperature screw compressor 33 is connected with the input end of a high-temperature area in the water-cooled cooler 35 through a pipeline, the output end of the high-temperature area in the water-cooled cooler 35 is connected with the input end of the low-temperature oil separator 36 through a pipeline, the cooling tower 3 is respectively connected with the input end and the output end of the low-temperature area in the water-cooled cooler 35 through a pipeline to form a cold water circulation loop, the oil return end of the low-temperature oil separator 36 is connected with the oil return input end of the low-, the transmission end of the three-way valve 44 is divided into two paths, one path of the transmission end of the three-way valve 44 is connected with the input end of the low temperature area in the condensing evaporator 7, the other path of the transmission end of the three-way valve 44 is connected with the input end of the constant pressure regulating valve 60, the output end of the constant pressure regulating valve 60 is connected with the input end of the low temperature area in the condensing evaporator 7, the output end of the low temperature area in the low temperature heat regenerator 34 is connected with the input end of the three-way valve 47 through a pipeline with a liquid path electromagnetic valve 68, the output end of the three-way valve 47 is divided into two paths, one path is connected with the input ends of two groups of electronic expansion valves 63/66, the output ends of the two groups of electronic expansion valves 63/66 are connected with the input ends of two groups of low, the output ends of the two groups of low-temperature evaporators 62/65 are connected to the input end of a high-temperature area in the low-temperature heat regenerator 34 through a three-way pipe 49 in common, the output end of the high-temperature area in the low-temperature heat regenerator 34 is connected with the return air input end of the low-temperature screw compressor 33 through a pipeline, the output end of the low-temperature stage expansion container 37 is connected with the input ends of one air suction low-pressure controllers 56 and 58 through a pipeline, the output ends of the low-pressure controllers 56 and 58 are connected with the return air input end of the low-temperature screw compressor 33 through a pipeline, the input end of the low-temperature stage expansion container 37 is also connected with the output ends of one system high-pressure controllers 56 and 58 through a pipeline, and the input ends of the.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the high-temperature unit, the air return input end of the high-temperature screw compressor 1 is connected with the output end of the high-temperature screw compressor 1 through a pipeline with a ball valve 14, a balance electromagnetic valve 15 and a liquid viewing mirror 16.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the high-temperature unit, a bypass pipeline with a liquid spraying electromagnetic valve 18 and a liquid spraying flow limiting valve 19 is further communicated to the air return input end of the high-temperature screw compressor 1 between the economizer 6 and a liquid path electromagnetic valve 20.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the high-temperature unit, an oil pressure difference switch 8, a high-pressure meter 9 and a pressure difference switch 10 are communicated and installed on a pipeline between a high-temperature screw compressor 1 and a high-temperature oil separator 2, and a low-pressure meter 11 is installed on a pipeline between the high-temperature screw compressor 1 and a condensing evaporator 7.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the high-temperature unit, a stop valve 13 and a stop valve 12 are correspondingly communicated and connected in pipelines at the input end and the output end of the high-temperature screw compressor respectively, and a stop valve 24 is communicated and installed in a pipeline between the water-cooled condenser 4 and the high-temperature liquid storage tank 5.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the low-temperature unit, a pipeline with a liquid spraying electromagnetic valve 46 and a liquid spraying flow limiting valve 45 is also led out between the low-temperature area of the low-temperature heat regenerator 34 and a liquid path electromagnetic valve 68 in a bypass mode and communicated to the input end of a three-way valve 50, the other input end of the three-way valve 50 is connected with the output end of the high-temperature area in the low-temperature heat regenerator 34, and the output end of the three-way valve 50 is connected with the.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the low-temperature unit, the return air input end and the return air output end of a low-temperature screw compressor 33 are communicated through a pipeline with an electromagnetic valve 53, a stop valve 54 and a liquid viewing mirror 55, a pressure difference switch 40, a high pressure gauge 39 and an oil pressure difference switch 38 are communicated and installed on the pipeline between the low-temperature screw compressor and a water-cooling cooler, and a low pressure gauge 41 is communicated and installed on the pipeline of the return air input end of the low-temperature screw compressor 33.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: in the low-temperature unit, a stop valve 43 is communicated and installed in a return air input end pipeline of a low-temperature screw compressor 33, a stop valve 42 is communicated and installed in a pipeline between the low-temperature screw compressor and a water-cooled cooler, an electromagnetic valve 68 is communicated and installed in a pipeline between the water-cooled cooler and a low-temperature oil separator, and an input end and an output end of a high-temperature area of a low-temperature heat regenerator 34 are communicated through a pipeline with a flow limiting valve 45 and an electromagnetic valve 46.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: cooling tower 3 passes through circulating water pump 29 respectively with water cooled condenser 4, the regional input of low temperature in water cooled cooler 35, the output is connected, and the gate valve is installed in the intercommunication in the pipeline that the regional input of low temperature in water cooled condenser 4 and water cooled condenser 35 is connected, the filter, the gate valve is installed in the intercommunication in the pipeline that the regional output of low temperature in water cooled condenser 4 and water cooled condenser 35 is connected, flow switch, the gate valve is installed in the intercommunication in the pipeline that the regional input of low temperature in water cooled condenser 4 and water cooled condenser 35 is connected, the filter, the gate valve is installed in the intercommunication in the pipeline that the regional output of low temperature in water cooled cooler is connected, flow switch.
The ultra-low temperature water source overlapping large refrigeration equipment is characterized in that: the high-temperature screw compressor 1 and the low-temperature screw compressor 33 are both water source screw compressors, the refrigerant of the high-temperature screw compressor is R404A, and the refrigerant of the low-temperature screw compressor is R23.
The invention adopts Siemens PLC-300 for control, a Siemens touch screen is operated by man-machine, parameters such as temperature and pressure of a unit are monitored through remote communication of a 485 interface, and start-stop operation of the unit is carried out, when the unit works, a high-temperature screw compressor (R404A) is started firstly, a low-temperature screw compressor (R23) is started through a water-cooled condenser in the high-temperature unit when the temperature of a condensation evaporator reaches a certain value (-20 ℃), air is cooled through two groups of low-temperature evaporators to reach a required ultra-low temperature set value (-55 ℃), and the like
The high-temperature unit and the low-temperature unit are superposed and compositely refrigerated, the PLC-300 is adopted for control, an ALCO expansion valve driver is used for controlling an electronic expansion valve, the pressure and the temperature of the unit are detected, and the start, the stop, the unloading and the loading of a screw machine, a fan and a water pump are controlled according to a low ultralow temperature set value.
The invention uses special refrigerants R404A and R23, the high-temperature unit adopts a water-cooled condenser 4, heat is radiated through a cooling tower 3, an evaporator of the high-temperature unit and a condenser 7 of the low-temperature unit are overlapped and efficiently exchange heat, the high-temperature unit condenses R404A through the water-cooled evaporator 4, and the refrigerant R23 in the condenser 7 of the low-temperature unit is evaporated in the evaporator 7 and used for cooling, so that the refrigerant R23 is changed from a gas state to a liquid state at the temperature of minus 20 ℃. Because the low-temperature screw compressor adopts R23 refrigerant, the saturation pressure is higher at normal temperature, in order to ensure that the system pressure is in a safe range, the system pressure at normal temperature is reduced, and the refrigeration effect under the low-temperature working condition is ensured, the low-temperature screw compressor system is additionally provided with an expansion container, and the low-pressure air supplement, high-pressure exhaust and expansion container constant-pressure technology is adopted during low-temperature work so as to ensure the normal operation of the screw compressor system under the low-temperature working condition. The high-temperature screw compressor 1(R404A) works at normal temperature, the water-cooled condenser 4 is cooled by a cooling water tower, the cooler part of the low-temperature unit is cooled by the evaporator 7 part of the high-temperature unit through the overlapped plate-type condensation evaporator 7, when the cooling temperature of the evaporator of the high-temperature unit reaches a certain value (-20 ℃), the low-temperature screw compressor 33 of the low-temperature unit is started, because R23 is low-temperature refrigerant, the saturation pressure is very high at normal temperature, the low-temperature screw compressor is filled with a certain amount of refrigerant (unsaturated), the pressure devices 56 and 56 of the system of the low-temperature unit are controlled in a safe range at normal temperature, when the low-temperature screw compressor 33 of the low-temperature unit is started, the suction pressure is lower than the lower limit value of the temperature saturation pressure range corresponding to R23, the low-pressure control electromagnetic valve 59 of the low-temperature stage expansion, when the suction pressure reaches the upper limit value of the temperature saturation pressure range corresponding to the R23, the electromagnetic valve 59 is closed; when the pressure corresponding to the exhaust temperature is higher than the upper limit value of the safety range of the exhaust pressure corresponding to R23, the high-pressure control electromagnetic valve 60 of the low-temperature stage expansion container is opened, the system injects the refrigerant into the low-temperature stage expansion container, and when the pressure corresponding to the exhaust temperature is lower than the lower limit value of the safety range of the pressure corresponding to the exhaust temperature corresponding to R23, the high-pressure control electromagnetic valve 60 is closed. The system pressure value of the low-temperature screw compressor is kept in a safe range at normal temperature, the low-temperature screw compressor can normally work at low temperature (-55 ℃), a Siemens PLC-300 controller and a touch screen are adopted for unit control, a Schneider air switch and an alternating current contactor are adopted, an indoor circulating centrifugal fan adopts variable frequency speed regulation, the compressor is 4-stage adjustable load, cooling tower fan heat dissipation, an efficient condensation circulating water pump and high-voltage protection, low-voltage protection, differential pressure protection, overload protection, power protection and various system protections are adopted, and the low-temperature screw compressor is provided with a 485 interface and can be subjected to modular control and remote monitoring.
The invention has the beneficial effects that: the invention provides an ultralow temperature working condition environment (-45-55 ℃) for inspecting the performance of mechanical and electrical products and equipment produced by people, and realizes places with ultralow temperature working conditions which are difficult to reach by common refrigeration equipment.
Drawings
Fig. 1 is an overall structural view of the present invention.
FIG. 2 is a schematic diagram of a portion of the high temperature assembly of the present invention.
FIG. 3 is a schematic diagram of a portion of the cryogenic unit of the present invention.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
As shown in fig. 1, an ultra-low temperature water source overlapping large-scale refrigeration equipment comprises a high temperature unit, a low temperature unit and a cooling tower 3, wherein: the high-temperature unit comprises a high-temperature screw compressor 1, a high-temperature oil separator 2, a water-cooled condenser 4, a high-temperature liquid storage tank 5, an economizer 6 and a condensing evaporator 7, wherein the output end of the high-temperature screw compressor 1 is connected with the input end of the high-temperature oil separator 2 through a pipeline, the output end of the high-temperature oil separator 2 is connected with the input end of a high-temperature area in the water-cooled condenser 4 through a pipeline, the oil return end of the high-temperature oil separator 2 is connected with the oil return input end of the high-temperature screw compressor 1 through a pipeline, the output end of the high-temperature area in the water-cooled condenser 4 is connected with the input end of the high-temperature liquid storage tank 5 through a pipeline with a filter 22, the cooling tower 3 is respectively connected with the input end and the output end of a low-temperature area in the, the output end of a liquid phase region in the economizer 6 is connected with the input end of a high-temperature region in the condensation evaporator 7 through a pipeline with a liquid path electromagnetic valve 20 and an electronic expansion valve 32, a bypass pipeline with an enthalpy-increasing electromagnetic valve 25 and an enthalpy-increasing expansion valve 26 is also communicated between the filter 22 and the economizer 6 to the input end of the liquid phase region in the economizer 6, the output end of the liquid phase region in the economizer 6 is connected with the enthalpy-increasing input end of the high-temperature screw compressor 1 through a pipeline, and the output end of the high-temperature region in the condensation evaporator 7 is connected with the air return input end of the high-temperature screw compressor 1 through a pipeline;
the low-temperature unit comprises a low-temperature screw compressor 33, a water-cooled cooler 35, a low-temperature oil separator 36, a low-temperature heat regenerator 34, two groups of low-temperature evaporators 62 and 65 and a low-temperature stage expansion container 37, wherein the output end of the low-temperature screw compressor 33 is connected with the input end of a high-temperature region in the water-cooled cooler 35 through a pipeline, the output end of the high-temperature region in the water-cooled cooler 35 is connected with the input end of the low-temperature oil separator 36 through a pipeline, the cooling tower 3 is respectively connected with the input end and the output end of the low-temperature region in the water-cooled cooler 35 through pipelines to form a cold water circulation loop, the oil return end of the low-temperature oil separator 36 is connected with the oil return input end of the low-temperature screw compressor 33 through a pipeline, the output end of the low-temperature oil separator 36 is connected with the input end of the low-temperature region in the condensing evaporator, the output end of the low temperature region in the condensing evaporator 7 is connected with the input end of the low temperature region in the low temperature heat regenerator 34 through a pipeline, the output end of the low temperature region in the low temperature heat regenerator 34 is divided into two paths through a pipeline with a liquid path solenoid valve 68 and is respectively connected with the input ends of two groups of low temperature evaporators 62 and 65 through being respectively communicated and provided with an electronic expansion valve 63 and an electronic expansion valve 66, the two groups of low temperature evaporators 62 and 65 are respectively and correspondingly provided with a fan 64 and a fan 67, the output ends of the two groups of low temperature evaporators 62 and 65 are commonly connected to the input end of the high temperature region in the low temperature heat regenerator 34 through pipelines, the output end of the high temperature region in the low temperature heat regenerator 34 is connected with the return air input end of the low temperature screw compressor 33 through a pipeline, the output end of the low temperature stage expansion container 37 is connected with the input end 59 of a low, the input of the low temperature stage expansion vessel 37 is also connected by a line to the output 58 of a high pressure controller, the input 56 of which is connected by a line to the output of the low temperature screw compressor 33.
In the high-temperature unit, the air return input end of the high-temperature screw compressor 1 is connected with the output end of the high-temperature screw compressor 1 through a pipeline with a ball valve 14, a balance electromagnetic valve 15 and a liquid viewing mirror 16.
In the high-temperature unit, a bypass pipeline with a liquid spraying electromagnetic valve 19 and a liquid spraying flow limiting valve 18 is communicated to the air return input end of the high-temperature screw compressor 1 between the economizer 6 and the liquid path electromagnetic valve.
In the high-temperature unit, an oil pressure difference switch 8, a high-pressure meter 9 and a pressure difference switch 10 are communicated and installed on a pipeline between a high-temperature screw compressor 1 and a high-temperature oil separator 2, and a low-pressure meter 11 is installed on a pipeline between the high-temperature screw compressor 1 and a condensing evaporator 7.
In the high-temperature unit, a stop valve 13 and a stop valve 12 are correspondingly communicated and connected in pipelines at the input end and the output end of a high-temperature screw compressor 1 respectively, a stop valve 23 is communicated and installed in a pipeline between a high-temperature oil separator 2 and a water-cooled condenser 4, and a stop valve 24 is communicated and installed in a pipeline between the water-cooled condenser 4 and a high-temperature liquid storage tank 5.
In the low-temperature unit, a pipeline which is led out by a bypass and provided with a liquid spraying electromagnetic valve 46 and a liquid spraying flow limiting valve 45 is also communicated to the output end of a high-temperature area in the low-temperature heat regenerator 34 between the low-temperature area of the low-temperature heat regenerator 34 and a liquid path electromagnetic valve 68.
In the low-temperature unit, the return air input end and the return air output end of a low-temperature screw compressor 33 are communicated through a pipeline with an electromagnetic valve 44, a pressure difference switch 40, a high-pressure meter 39 and an oil pressure difference switch 38 are communicated and installed on the pipeline between the low-temperature screw compressor 33 and a water-cooling cooler 35, and a low-pressure meter 41 is communicated and installed on the return air input end pipeline of the low-temperature screw compressor 33.
In the low-temperature unit, a stop valve 43 is installed in a pipeline of a return air input end of a low-temperature screw compressor 33 in a communicating manner, a stop valve 42 is installed in a pipeline between the low-temperature screw compressor 33 and a water-cooling cooler 35 in a communicating manner, an electromagnetic valve 48 is installed in a pipeline between the water-cooling cooler 35 and a low-temperature oil separator 36 in a communicating manner, a ball valve 53, an electromagnetic valve 54 and a liquid viewing mirror 55 are installed in a pipeline between the low-temperature oil separator 36 and the low-temperature screw compressor 33 in a communicating manner, and an input end and an output end of a high-temperature area of a low.
The cooling tower 3 is connected with the input end and the output end of the low temperature area in the water-cooled condenser 4 and the water-cooled cooler 35 respectively through a circulating water pump 29.
The high-temperature screw compressor 1 and the low-temperature screw compressor 33 are both water source screw compressors, the refrigerant of the high-temperature screw compressor 1 is R404A, and the refrigerant of the low-temperature screw compressor 33 is R23.
The invention adopts Siemens PLC-300 to form an electric cabinet 61 which is used for receiving signals of a measuring instrument in a system and realizing the control of the system.
The specific working process of the invention is as follows:
when the equipment works, firstly, the temperature T1 (-20 ℃) of a condensation evaporator 7 of a high-temperature screw compressor 1 is set according to user requirements, meanwhile, the return air temperature T2 (-55 ℃) of an evaporator 62/65 of a low-temperature unit is set, various protection parameters such as pressure, current and exhaust temperature and working parameters of an electronic expansion valve are set, after the equipment is electrified, a circulating water pump 29 is started, time delay is carried out for 2-3 minutes sequentially, a cooling tower 3, low-temperature evaporation fans 64 and 67, system main solenoid valves 20 and 68 and a high-temperature screw compressor 1 start in a star triangle mode, the high-temperature screw compressor 1 starts to refrigerate, when the temperature of the evaporator is smaller than a set temperature T1 and is delayed for 3 minutes, the low-temperature screw compressor 33 starts in a star triangle mode, the working load of the low-temperature screw compressor 33 is gradually increased to 100% from 25%, when the return air temperature of low-temperature evaporators 62 and 65 is lower than a set temperature T2, the load of the low-temperature screw compressor 33 is gradually reduced, the low-temperature screw compressor 33 is 100% -75% -50% to shut down, when the return air temperature of the low-temperature evaporators 62 and 65 are lower than a set temperature is lower than a set temperature, the set temperature of the low-temperature evaporator 62 and 65, the high-temperature evaporator 33 is lower than a set temperature condenser, the high-temperature compressor 33, the high-temperature compressor is started, the high-temperature compressor is controlled by a high-temperature compression-pressure compressor 33, the high-pressure compressor, the high-pressure compressor, the high-temperature compression-pressure compressor is controlled by a low-pressure compressor, the high-pressure compressor 33, the high-pressure compressor is controlled by a low-pressure compressor, the high-pressure compressor, the high-pressure compressor is controlled by a high-pressure compressor 33-pressure compressor, the high-pressure compressor is controlled by a low-pressure compressor, the high-pressure compressor, the low-pressure compressor, the high-pressure compressor is controlled by a low-pressure compressor, the high-pressure compressor, the low-pressure.
In a normal state, after the unit is powered on, a starting instruction is given through a touch screen on the control box 61, the circulating water pump 29 is started, the cooling fan of the cooling tower 3 is started, the circulating fan motors 64 and 67 of the low-temperature evaporator are started, the high-temperature screw compressor 1 is started after 2-3 minutes, R404A refrigerant enters the oil separator 2 through the exhaust port of the high-temperature screw compressor 1 to be subjected to oil-gas separation and returns to the low-pressure oil return port of the high-temperature screw compressor 1, the gas enters the input port of the stop valve 23 through the exhaust port of the high-temperature oil separator 2 and is connected with the refrigerant input port of the water-cooled condenser 4 through the output port of the stop valve 23, the refrigerant output port of the water-cooled condenser 4 is connected with the input port of the stop valve 24, the, the first branch is connected with the input port of the economizer 6, the second branch is connected with the input port of the enthalpy-increasing solenoid valve 25, the output end of the enthalpy-increasing solenoid valve 25 is connected with the input end of the enthalpy-increasing expansion valve 26, the input end of the enthalpy-increasing expansion valve 26 is connected with the input end of the economizer 6, refrigerant R404A is evaporated in the economizer 6, gas of the refrigerant passes through the output end of the economizer 6 and is connected with the input end of the check valve 21, the output end of the check valve 21 is connected with a return port of the compressor 1, the liquid phase output end of the economizer 6 is connected with the input end of the tee 27, the first branch is connected with the main solenoid valve 20 and the electronic expansion valve 32, the output end of the refrigerant is connected with the gas phase input end of the condensation evaporator 7, the second. Refrigerant R404A evaporates in the condenser-evaporator 7, the gas is output from the other output end of the condenser-evaporator 7 and connected with the input of the stop valve 13, the output of the stop valve 13 is connected with the air return end of the high temperature screw compressor 1, the system is provided with an oil pressure differential controller 8 for preventing the oil filter from being blocked, a differential pressure switch 10 for preventing the high pressure of the compressor from being too high and the low pressure from being too low, a high pressure gauge 9 for displaying the high pressure of the system, and a low pressure gauge 11 for displaying the low pressure of the system.
When the temperature sensor 28 (PT-1000) of the evaporator evaporation part of the condensation evaporator 7 detects that the temperature of a refrigerant R404A is reduced to-20 ℃, the low-temperature screw compressor 33 is started to compress the refrigerant R23 and discharge high-temperature and high-pressure gas, the gas reaches the input end of the stop valve 42 through the output end of the gas, the output end of the stop valve 42 is connected with the other input end of the water-cooled cooler 35, the high-temperature gas is cooled in the water-cooled cooler 35 and then is connected with the input end of the electromagnetic valve 48 through the output end, the output end of the electromagnetic valve 48 is connected with the input end of the low-temperature oil separator 36, the output end of the low-temperature oil separator 36 is: one output end of the three-way pipe 44 is connected with the input end of a constant pressure controller 60, the output end of the constant pressure controller 60 is connected with the input end of the low-temperature stage expansion container 37, when the pressure P of the low-temperature stage expansion container 37 is less than or equal to 0.6MPa, the pressure controller 60 is switched ON (ON), and when the pressure P is greater than or equal to 0.85MPa, the pressure controller 60 is switched OFF (OFF), so that the pressure of the low-temperature stage expansion container 37 is kept within a certain safety range, and a branch circuit II: the other output end of the three-way pipe is connected with the input end of the condensation part of the condensation evaporator 7, the refrigerant R23 is condensed into liquid at the condensation part of the condensation evaporator 7 and then output, the output end of the condensation evaporator 7 is connected with the input end of the low-temperature heat regenerator 34, the liquid refrigerant R23 is connected with the input end of the three-way pipe 47 through the main output end of the liquid phase of the low-temperature heat regenerator 34 after the low-temperature heat regenerator 34 recovers the return air temperature heat, and the three-way pipe 47 is divided into two branch pipes, namely a first branch pipe: the output end of the three-way pipe 47 is connected with the input end of the electronic expansion valve 63, the output end of the electronic expansion valve 63 is connected with the input end of the low-temperature evaporator 62, the output end of the low-temperature evaporator 62 is connected with the input end of the three-way pipe 49, and the branch pipe II: the other output end of the three-way pipe 47 is connected with the input end of an electronic expansion valve 66, the output end of the electronic expansion valve 66 is connected with the input end of a low-temperature evaporator 65, the output end of the low-temperature evaporator 65 is connected with the other input end of the three-way pipe 49, the output end of the three-way pipe 49 is connected with the gas phase input end of the low-temperature heat regenerator 34, and the R23 refrigerant low-temperature gas is heated by the low-temperature heat regenerator 34 and then output and is connected with the gas. When the compressor 33 operates, the switch of the electromagnetic valve 59 is switched off, when the pressure P of the low-pressure controller 57 is less than or equal to 0.1MPa, the switch of the low-pressure controller 57 is switched on, the electromagnetic valve 59 is switched on, the low-temperature stage expansion container 37 replenishes gas to the low-pressure end of the compressor 33, the suction pressure is improved, the switch of the low-pressure controller 57 is switched off, and the electromagnetic valve 59 is switched off; when the exhaust pressure P of the compressor 33 is more than or equal to 1.6MPa, the switch of the high-pressure controller 56 is closed, the electromagnetic valve 58 is opened, the low-temperature stage expansion container 37 is inflated, the exhaust pressure P is less than or equal to 1.2MPa, the switch of the high-pressure controller 56 is opened, and the electromagnetic valve 58 is opened; when the low-temperature screw compressor 33 stops operating, the electromagnetic valve 54 is conducted, and the high-pressure and low-pressure pressures of the system are rapidly balanced. The low temperature system is provided with an oil pressure difference switch 38, a pressure difference switch 40 for high pressure protection and low pressure protection of the system, a high pressure meter 39 and a low pressure meter 41.
Generally speaking, the low-temperature environment temperature is fed back to the controller in real time through the temperature sensor of the low-temperature return air of the equipment, the low-temperature environment temperature is compared with a set value, when the temperature sensed by the temperature sensor is lower than the set value, the controller gives a signal, and the low-temperature screw compressor 33 and the high-temperature screw compressor 1 stop working; when the low-temperature environment temperature is higher than the set value plus the temperature difference, the controller gives a signal to start the low-temperature screw compressor 33 and the high-temperature screw compressor 1, so that the low-temperature environment temperature reaches the set value, and the corresponding compressor is stopped when the system is protected.
The above examples are merely illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention are intended to fall within the scope of the present invention defined by the claims.
Claims (10)
1. The utility model provides an ultra-low temperature water source overlapping large-scale refrigeration plant which characterized in that: including high temperature unit, cryogenic unit, cooling tower, wherein: the high-temperature unit comprises a high-temperature screw compressor 1, a high-temperature oil separator 2, a water-cooled condenser 4, a high-temperature liquid storage tank 5, an economizer 6 and a condensing evaporator 7, wherein the output end of the high-temperature screw compressor is connected with the input end of the high-temperature oil separator through a pipeline, the output end of the high-temperature oil separator 2 is connected with the input end of a high-temperature area in the water-cooled condenser 4 through a pipeline, the oil return end of the high-temperature oil separator 2 is connected with the oil return input end of the high-temperature screw compressor 1 through a pipeline, the output end of the high-temperature area in the water-cooled condenser 4 is connected with the input end of the high-temperature liquid storage tank 5 through a pipeline with a filter, the cooling tower 3 is respectively connected with the input end and the output end of a low-temperature area in the, the output end of a liquid phase region in the economizer 6 is connected with the input end of a high-temperature region in the condensation evaporator 7 through a pipeline with a liquid path electromagnetic valve 20 and an electronic expansion valve 32, a bypass pipeline with an enthalpy-increasing electromagnetic valve 25 and an enthalpy-increasing expansion valve 26 is communicated to the input end of the liquid phase region in the economizer 6 between the filter 22 and the economizer, the output end of the liquid phase region in the economizer 6 is connected with the enthalpy-increasing input end of the high-temperature screw compressor 1 through a pipeline, and the output end of the high-temperature region in the condensation evaporator 7 is connected with the return air input end of the high-temperature screw compressor 1 through a pipeline;
the low-temperature unit comprises a low-temperature screw compressor 33, a water-cooled cooler 35, a low-temperature oil separator 36, a low-temperature condenser 7, a low-temperature heat regenerator 34, evaporation fans 64/67, two groups of low-temperature evaporators 62/65, a low-temperature stage expansion container 37, an exhaust pressure controller 60, suction pressure controllers 57 and 59 and system pressure controllers 56 and 58, wherein the output end of the low-temperature screw compressor 33 is connected with the input end of a high-temperature area in the water-cooled cooler 35 through a pipeline, the output end of the high-temperature area in the water-cooled cooler 35 is connected with the input end of the low-temperature oil separator 36 through a pipeline, the cooling tower 3 is respectively connected with the input end and the output end of the low-temperature area in the water-cooled cooler 35 through a pipeline to form a cold water circulation loop, the oil return end of the low-temperature oil separator 36 is connected with the oil return input end of the low-, the transmission end of the three-way valve 44 is divided into two paths, one path of the transmission end of the three-way valve 44 is connected with the input end of the low temperature area in the condensing evaporator 7, the other path of the transmission end of the three-way valve 44 is connected with the input end of the constant pressure regulating valve 60, the output end of the constant pressure regulating valve 60 is connected with the input end of the low temperature area in the condensing evaporator 7, the output end of the low temperature area in the low temperature heat regenerator 34 is connected with the input end of the three-way valve 47 through a pipeline with a liquid path electromagnetic valve 68, the output end of the three-way valve 47 is divided into two paths, one path is connected with the input ends of two groups of electronic expansion valves 63/66, the output ends of the two groups of electronic expansion valves 63/66 are connected with the input ends of two groups of low, the output ends of the two groups of low-temperature evaporators 62/65 are connected to the input end of a high-temperature area in the low-temperature heat regenerator 34 through a three-way pipe 49 in common, the output end of the high-temperature area in the low-temperature heat regenerator 34 is connected with the return air input end of the low-temperature screw compressor 33 through a pipeline, the output end of the low-temperature stage expansion container 37 is connected with the input ends of one air suction low-pressure controllers 56 and 58 through a pipeline, the output ends of the low-pressure controllers 56 and 58 are connected with the return air input end of the low-temperature screw compressor 33 through a pipeline, the input end of the low-temperature stage expansion container 37 is also connected with the output ends of one system high-pressure controllers 56 and 58 through a pipeline, and the input ends of the.
2. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the high-temperature unit, the air return input end of the high-temperature screw compressor 1 is connected with the output end of the high-temperature screw compressor 1 through a pipeline with a ball valve 14, a balance electromagnetic valve 15 and a liquid viewing mirror 16.
3. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the high-temperature unit, a bypass pipeline with a liquid spraying electromagnetic valve 18 and a liquid spraying flow limiting valve 19 is further communicated to the air return input end of the high-temperature screw compressor 1 between the economizer 6 and a liquid path electromagnetic valve 20.
4. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the high-temperature unit, an oil pressure difference switch 8, a high-pressure meter 9 and a pressure difference switch 10 are communicated and installed on a pipeline between a high-temperature screw compressor 1 and a high-temperature oil separator 2, and a low-pressure meter 11 is installed on a pipeline between the high-temperature screw compressor 1 and a condensing evaporator 7.
5. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the high-temperature unit, a stop valve 13 and a stop valve 12 are correspondingly communicated and connected in pipelines at the input end and the output end of the high-temperature screw compressor respectively, and a stop valve 24 is communicated and installed in a pipeline between the water-cooled condenser 4 and the high-temperature liquid storage tank 5.
6. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the low-temperature unit, a pipeline with a liquid spraying electromagnetic valve 46 and a liquid spraying flow limiting valve 45 is also led out between the low-temperature area of the low-temperature heat regenerator 34 and a liquid path electromagnetic valve 68 in a bypass mode and communicated to the input end of a three-way valve 50, the other input end of the three-way valve 50 is connected with the output end of the high-temperature area in the low-temperature heat regenerator 34, and the output end of the three-way valve 50 is connected with the.
7. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the low-temperature unit, the return air input end and the return air output end of a low-temperature screw compressor 33 are communicated through a pipeline with an electromagnetic valve 53, a stop valve 54 and a liquid viewing mirror 55, a pressure difference switch 40, a high pressure gauge 39 and an oil pressure difference switch 38 are communicated and installed on the pipeline between the low-temperature screw compressor and a water-cooling cooler, and a low pressure gauge 41 is communicated and installed on the pipeline of the return air input end of the low-temperature screw compressor 33.
8. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: in the low-temperature unit, a stop valve 43 is communicated and installed in a return air input end pipeline of a low-temperature screw compressor 33, a stop valve 42 is communicated and installed in a pipeline between the low-temperature screw compressor and a water-cooled cooler, an electromagnetic valve 68 is communicated and installed in a pipeline between the water-cooled cooler and a low-temperature oil separator, and an input end and an output end of a high-temperature area of a low-temperature heat regenerator 34 are communicated through a pipeline with a flow limiting valve 45 and an electromagnetic valve 46.
9. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: cooling tower 3 is connected with water cooled condenser 4, the regional input of low temperature in water cooled cooler 35, output respectively through circulating water pump 29, and the gate valve is installed in the intercommunication in the pipeline that the regional input of low temperature in water cooled condenser 4, 35 is connected, the gate valve is installed in the intercommunication in the pipeline that the regional output of low temperature in water cooled condenser is connected, flow switch, the gate valve is installed in the intercommunication in the pipeline that the regional input of low temperature in water cooled cooler is connected, the filter, the gate valve is installed in the intercommunication in the pipeline that the regional output of low temperature in water cooled cooler is connected, flow switch.
10. The ultra-low temperature water source cascade large refrigerating equipment as claimed in claim 1, characterized in that: the high-temperature screw compressor 1 and the low-temperature screw compressor 33 are both water source screw compressors, the refrigerant of the high-temperature screw compressor is R404A, and the refrigerant of the low-temperature screw compressor is R23.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910846371.4A CN111174454A (en) | 2019-09-09 | 2019-09-09 | Ultra-low temperature water source overlapping large refrigeration equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910846371.4A CN111174454A (en) | 2019-09-09 | 2019-09-09 | Ultra-low temperature water source overlapping large refrigeration equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111174454A true CN111174454A (en) | 2020-05-19 |
Family
ID=70622399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910846371.4A Pending CN111174454A (en) | 2019-09-09 | 2019-09-09 | Ultra-low temperature water source overlapping large refrigeration equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111174454A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114087744A (en) * | 2020-07-29 | 2022-02-25 | 广东美的制冷设备有限公司 | Air conditioner, air conditioner control method and device and readable storage medium |
-
2019
- 2019-09-09 CN CN201910846371.4A patent/CN111174454A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114087744A (en) * | 2020-07-29 | 2022-02-25 | 广东美的制冷设备有限公司 | Air conditioner, air conditioner control method and device and readable storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3299747B1 (en) | Switchable two-stage cascade energy-saving ultralow-temperature refrigeration system for ships | |
| WO2017194035A1 (en) | Method for increasing refrigeration or heat pump system efficiency, and operating method | |
| CN112212532B (en) | Control method of variable-frequency refrigeration system | |
| CN103486754A (en) | Energy-saving middle temperature refrigerant/middle temperature refrigerant cascade refrigeration system | |
| CN111271888A (en) | Refrigeration equipment capable of automatically balancing refrigerant charging amount | |
| CN111156756B (en) | Self-adaptive charging amount adjusting system and control method in cooling process of ultralow temperature refrigerator | |
| US20220205692A1 (en) | Oil return control method of multi-functional multi-split system with double four-way valves | |
| CN105135731A (en) | Refrigerating system, refrigerating plant and temperature control method of refrigerating plant | |
| CN111174454A (en) | Ultra-low temperature water source overlapping large refrigeration equipment | |
| CN212109054U (en) | Ultra-low temperature water source overlapping large refrigeration equipment | |
| EP3390822A1 (en) | Helium compressor with dual after-coolers | |
| CN110001913B (en) | Full-automatic ship refrigerating device based on PLC control system | |
| CN111121352A (en) | Continuous defrosting refrigeration control system capable of reducing heat leakage | |
| CN215765835U (en) | Cooling system and refrigeration equipment | |
| CN113915876B (en) | Refrigerator and control method thereof | |
| CN212227442U (en) | Energy-saving explosion-proof one-driving-multiple refrigeration heating temperature control system | |
| CN114198872B (en) | Machine room air conditioner, operation control method and device of machine room air conditioner | |
| CN113513852A (en) | Cooling system, refrigeration equipment and cooling method | |
| CN207662004U (en) | Air-conditioning device and refrigeration storage system | |
| CN113776863B (en) | Comprehensive test device and method for remote refrigeration appliance | |
| CN113375354A (en) | Refrigeration system and control method thereof | |
| CN1272593C (en) | Lithium brominate absorptive-type refrigerator with cryogen steam regulation and antifreeze device | |
| CN217464989U (en) | Refrigeration control system of screw refrigerating unit | |
| CN212987690U (en) | Multi-connected cold storage air cooler and system thereof | |
| CN210089170U (en) | Cold source system based on magnetic suspension unit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |