Steel pipeline assembly of variable-frequency centrifugal air-cooled heat pump unit
By adopting standard seamless steel pipe elbows and straight/reducible steel pipe design, the steel pipeline components of variable frequency centrifugal air-cooled heat pump units have been solved, and the problems of complex assembly and high cost in the existing technology have been achieved, and low-cost, efficient assembly and stable operation have been achieved.
Patent Information
- Application Number
- CN202422448539.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-10
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2034-10-10
AI Technical Summary
In the prior art, the steel pipeline components of the variable frequency centrifugal air-cooled heat pump unit need to be bent and molded, resulting in increased initial investment and material costs, and complex assembly.
Standard seamless steel pipe elbows and straight/reduced steel pipes are adopted, and a reasonable steel pipe assembly structure is designed without initial investment in bending equipment, simplifying the assembly process, and reasonably matching unit components.
It achieves low cost of steel pipeline components, simple and efficient assembly, and stable overall unit operation, reducing initial investment and material costs.
Smart Images
Figure CN223191870U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of central air-conditioning systems, in particular to a steel pipeline component of a variable frequency centrifugal air-cooled heat pump unit. Background Art
[0002] For large central air-conditioning systems, some main circulation loops use seamless steel pipes due to the large refrigerant circulation volume and require various control valves to ensure efficient and stable operation of the unit.
[0003] Compared with general TP2-M2 seamless copper tubes, seamless steel tubes have poorer ductility and are not easy to bend or form into one piece. For centrifugal air-cooled heat pump units, there are more steel pipe components and many control valves. If one-piece bent steel tubes are used for piping, part of the pipes need to be cut to facilitate assembly with control valves, etc. under the conditions of meeting process production. Although this can reduce the piping time of the unit, the overall initial investment cost and material cost of the unit will be greatly increased. Utility Model Content
[0004] In view of this, the utility model aims to propose a variable frequency centrifugal air-cooled heat pump unit steel pipe assembly, which adopts standard seamless steel pipe elbows and straight pipes / reducing diameter steel pipes, without the need for initial investment in bending equipment, making the assembly of system control valves and pipelines simple and convenient, and the overall unit steel pipe assembly has low cost, orderly assembly, simplicity and efficiency.
[0005] In order to achieve the above-mentioned purpose, the technical solution of the utility model is achieved as follows:
[0006] The utility model provides a variable frequency centrifugal air-cooled heat pump unit steel pipeline assembly, comprising a compressor, a four-way valve, a gas-liquid separator, an air-cooled heat exchanger and a water-cooled heat exchanger arranged on the bottom frame of the unit;
[0007] The exhaust port of the compressor is connected to the D port of the four-way valve through an exhaust steel pipeline assembly. A hot gas bypass steel pipeline assembly is led out of the exhaust steel pipeline assembly near the air outlet and is connected to the gas-liquid separator. The air intake of the compressor is connected to the gas-liquid separator through an air intake steel pipeline assembly. The shutdown bypass steel pipeline assembly is led out from the air inlet of the exhaust steel pipeline assembly and leads to the air outlet of the air intake steel pipeline assembly.
[0008] The C port of the four-way valve is connected to a plurality of the air-cooled heat exchangers through a centralized steel pipeline assembly, and the plurality of the air-cooled heat exchangers are connected to the water-cooled heat exchanger after being centralized. The water-cooled heat exchanger is respectively connected to the intake steel pipeline assembly and the E port of the four-way valve through an intake bypass steel pipeline assembly;
[0009] The S port of the four-way valve is connected to the inlet of the gas-liquid separator through a low-pressure steel pipeline component.
[0010] Furthermore, the exhaust steel pipe assembly is composed of a first pipe, a second pipe, a first tee, a third pipe, a first valve, a fourth pipe, a second valve, a fifth pipe, a first elbow, a sixth pipe, a second tee, a seventh pipe, a second elbow, an eighth pipe and a third elbow, which are sequentially spliced together. The first pipe is connected to the exhaust port of the compressor, and the third elbow is connected to the D port of the four-way valve.
[0011] The first three-way piece is provided with a first tapered joint, and the third pipeline is provided with a third valve and a second tapered joint.
[0012] Furthermore, the hot gas bypass steel pipeline assembly is composed of the ninth pipeline, the fourth elbow, the tenth pipeline, the fourth valve, the eleventh pipeline, the fifth elbow, the twelfth pipeline, the sixth elbow, the thirteenth pipeline and the seventh elbow, which are spliced in sequence. The ninth pipeline is connected to the second tee piece, and the seventh elbow is connected to the gas-liquid separator.
[0013] Furthermore, the air intake steel pipeline assembly is composed of a fourteenth pipeline, a fifth valve, a fifteenth pipeline, an eighth elbow, a sixteenth pipeline, a seventeenth pipeline, a ninth elbow, a third tee, an eighteenth pipeline, a tenth elbow, and a nineteenth pipeline, which are sequentially spliced together. The fourteenth pipeline is connected to the air intake port of the compressor, and the nineteenth pipeline is connected to the gas-liquid separator.
[0014] The sixteenth pipeline is provided with a third tapered joint, a fourth tapered joint and a fifth tapered joint.
[0015] Furthermore, the intake bypass steel pipeline assembly is composed of the eleventh elbow, the twentieth pipeline, the twenty-first pipeline, the twelfth elbow, the fourth three-way piece, the twenty-second pipeline, the twenty-third pipeline, the thirteenth elbow, the sixth valve, and the twenty-fourth pipeline, which are spliced in sequence. The eleventh elbow is connected to the E port of the four-way valve, the twenty-second pipeline is connected to the water-cooled heat exchanger, and the twenty-fourth pipeline is connected to the third three-way piece.
[0016] Furthermore, the first pipeline, the third pipeline, the fourth pipeline, the fifth pipeline, the sixth pipeline, the seventh pipeline, the eighth pipeline, the ninth pipeline, the tenth pipeline, the eleventh pipeline, the twelfth pipeline, the thirteenth pipeline, the fourteenth pipeline, the fifteenth pipeline, the sixteenth pipeline, the seventeenth pipeline, the eighteenth pipeline, the nineteenth pipeline, the twentieth pipeline, the twenty-first pipeline, the twenty-second pipeline, the twenty-third pipeline, and the twenty-fourth pipeline are all straight steel pipes;
[0017] The second pipeline and the seventh pipeline are both seamless steel pipes with reducer joints, wherein the second pipeline is a DN40 specification converted to a DN50 specification, and the seventh pipeline is a DN50 specification converted to a DN65 specification.
[0018] Furthermore, the first elbow, the second elbow, the third elbow, the fourth elbow, the fifth elbow, the sixth elbow, the seventh elbow, the eighth elbow, the ninth elbow, the tenth elbow, the eleventh elbow, the twelfth elbow and the thirteenth elbow are all 90° seamless steel pipe long elbows, among which the first elbow is DN50, the second elbow and the third elbow are DN65, and the rest are DN80.
[0019] Furthermore, the first valve is a stop valve, the second valve and the fifth valve are manual shut-off valves, the third valve is a safety pressure relief valve, the fourth valve is an electric ball valve, and the sixth valve is an electric butterfly valve.
[0020] Furthermore, the first tee is a reducing steel pipe tee, with DN40 specifications at both ends changing to DN35 specifications at the middle outlet; the second, third and fourth tees are all equal-diameter steel pipe tees, among which the second tee is DN50 in specification, and the third and fourth tees are DN80 in specification.
[0021] Furthermore, the first tapered joint, the third tapered joint, and the fourth tapered joint are all NPT1 / 4 interfaces. The first tapered joint is used to install a high-pressure sensor, the third tapered joint is used to install a cooling low-pressure sensor, a heating low-pressure sensor, a cooling low-pressure switch, and a heating low-pressure switch, and the fourth tapered joint is used to install an intake temperature sensor;
[0022] The second tapered joint and the fifth tapered joint are RC3 / 8 interfaces, which are used to install the exhaust temperature sensor and the shutdown bypass steel pipe assembly respectively.
[0023] Compared with the prior art, the variable frequency centrifugal air-cooled heat pump unit steel pipe assembly described in the present invention has the following beneficial effects:
[0024] The utility model describes a variable frequency centrifugal air-cooled heat pump unit steel pipeline assembly using market standard seamless steel pipe elbows and straight pipes / reducing diameter steel pipes, which does not require initial investment in bending equipment, making the assembly of system control valves and pipelines simple and convenient; at the same time, the exhaust steel pipeline assembly, hot gas bypass steel pipeline assembly, collecting and distribution pipe steel pipeline assembly, shutdown bypass steel pipeline assembly, intake steel pipeline assembly, and intake bypass steel pipeline assembly are orderly combined and assembled, and reasonably matched with the unit compressor, air-cooled heat exchanger, four-way valve, gas-liquid separator, etc., and uniformly installed on the bottom frame of the unit, so that the steel pipeline assembly of the overall unit has low cost, orderly assembly, simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:
[0026] Figure 1 This is a general assembly diagram of the steel piping components of a variable frequency centrifugal air-cooled heat pump unit according to an embodiment of the present utility model;
[0027] Figure 2 This is a structural diagram of the exhaust steel pipeline assembly according to an embodiment of the present utility model;
[0028] Figure 3 This is a structural diagram of the hot gas bypass steel pipeline assembly according to an embodiment of the present utility model;
[0029] Figure 4 This is a structural diagram of the manifold steel pipeline assembly according to an embodiment of the present utility model;
[0030] Figure 5 This is a structural diagram of the steel pipeline assembly of the suction pipe according to an embodiment of the present utility model;
[0031] Figure 6 This is a structural diagram of the suction bypass steel pipeline assembly according to an embodiment of the present utility model;
[0032] Figure 7 This is a unit system diagram corresponding to the steel pipeline components of a variable frequency centrifugal air-cooled heat pump unit described in an embodiment of the present utility model.
[0033] Description of reference numerals:
[0034] 1. Compressor; 2. Exhaust steel pipe assembly; 2-1. First pipe; 2-2. Second pipe; 2-3. First tee; 2-4. Third pipe; 2-5. First valve; 2-6. Fourth pipe; 2-7. Second valve; 2-8. Fifth pipe; 2-9. First elbow; 2-10. Sixth pipe; 2-11. Second tee; 2-12. Seventh pipe; 2-13. Second elbow; 2-14. Eighth pipe; 2-15. Third elbow; 2-1 6. First taper joint; 2-17. Third valve; 2-18. Second taper joint; 3. Hot gas bypass steel pipe assembly; 3-1. Ninth pipe; 3-2. Fourth elbow; 3-3. Tenth pipe; 3-4. Fourth valve; 3-5. Eleventh pipe; 3-6. Fifth elbow; 3-7. Twelfth pipe; 3-8. Sixth elbow; 3-9. Thirteenth pipe; 3-10. Seventh elbow; 4. Four-way valve; 5. Manifold steel pipe assembly; 6. Shutdown bypass steel pipe 7. Suction steel pipe assembly; 7-1. Fourteenth pipe; 7-2. Fifth valve; 7-3. Fifteenth pipe; 7-4. Eighth elbow; 7-5. Sixteenth pipe; 7-6. Seventeenth pipe; 7-7. Ninth elbow; 7-8. Third tee; 7-9. Eighteenth pipe; 7-10. Tenth elbow; 7-11. Nineteenth pipe; 7-12. Third taper joint; 7-13. Fourth taper joint; 7-14. Fifth taper joint; 8. Suction Bypass steel pipeline assembly; 8-1, 11th elbow; 8-2, 20th pipeline; 8-3, 21st pipeline; 8-4, 12th elbow; 8-5, 4th three-way fitting; 8-6, 22nd pipeline; 8-7, 23rd pipeline; 8-8, 13th elbow; 8-9, 6th valve; 8-10, 24th pipeline; 9, low-pressure steel pipeline assembly; 10, gas-liquid separator; 11, air-cooled heat exchanger; 12, throttle valve; 13, water-cooled heat exchanger; 14, bottom frame. DETAILED DESCRIPTION
[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.
[0036] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.
[0037] See also Figure 1 and Figure 7 As shown, a variable frequency centrifugal air-cooled heat pump unit steel pipeline assembly includes a compressor 1, a four-way valve 4, a gas-liquid separator 10, an air-cooled heat exchanger 11 and a water-cooled heat exchanger 13 arranged on the bottom frame 14 of the unit;
[0038] The exhaust port of the compressor 1 is connected to the D port of the four-way valve 4 through the exhaust steel pipe assembly 2. The exhaust steel pipe assembly 2 leads to a hot gas bypass steel pipe assembly 3 near the outlet and is connected to the gas-liquid separator 10. The intake port of the compressor 1 is connected to the gas-liquid separator 10 through the intake steel pipe assembly 7. The shutdown bypass steel pipe assembly 6 is led out from the air inlet of the exhaust steel pipe assembly 2 and leads to the outlet of the intake steel pipe assembly 7.
[0039] The C port of the four-way valve 4 is connected to several air-cooled heat exchangers 11 through the steel pipe assembly 5. Figure 4 As shown, several air-cooled heat exchangers 11 are connected to the water-cooled heat exchanger 13 after being collected together. The water-cooled heat exchanger 13 is connected to the intake steel pipeline assembly 7 and the E port of the four-way valve 4 respectively through the intake bypass steel pipeline assembly 8;
[0040] The S port of the four-way valve 4 is connected to the inlet of the gas-liquid separator 10 through a low-pressure steel pipeline assembly 9 .
[0041] Specifically, in this embodiment, the component adopts market-standard seamless steel pipe elbows and straight pipes / reducing diameter steel pipes, and does not require initial investment in bending equipment, making the assembly of system control valves and pipelines simple and convenient; at the same time, the exhaust steel pipeline assembly 2, hot gas bypass steel pipeline assembly 3, collecting and distribution pipe steel pipeline assembly 5, shutdown bypass steel pipeline assembly 6, intake steel pipeline assembly 7, and intake bypass steel pipeline assembly 8 are orderly combined and assembled, and reasonably matched with the unit compressor 1, air-cooled heat exchanger 11, four-way valve 4, gas-liquid separator 10, etc., and uniformly installed on the bottom frame 14 of the unit, so that the steel pipeline assembly of the entire unit is low-cost, orderly assembled, simple and efficient.
[0042] It should be noted that the compressor 1 used in this embodiment is a variable frequency magnetic suspension / gas suspension / liquid suspension centrifugal two-stage compressor; the four-way valve 4 is an oil-free electric four-way valve with four ports C / D / E / S, of which the D port interface is a flange connection with a DN65 interface specification, and the C / E / S port interface is a flange connection with a DN80 interface specification; the air-cooled heat exchanger 11 is a flooded / dry shell and tube heat exchanger; the bottom frame 14 is a 10#~12# welded integrated channel steel structure.
[0043] In some embodiments, as Figure 2 As shown, the exhaust steel pipeline assembly 2 is composed of the first pipeline 2-1, the second pipeline 2-2, the first tee 2-3, the third pipeline 2-4, the first valve 2-5, the fourth pipeline 2-6, the second valve 2-7, the fifth pipeline 2-8, the first elbow 2-9, the sixth pipeline 2-10, the second tee 2-11, the seventh pipeline 2-12, the second elbow 2-13, the eighth pipeline 2-14 and the third elbow 2-15, which are sequentially spliced together. The first pipeline 2-1 is connected to the exhaust port of the compressor 1, and the third elbow 2-4 is connected to the D port of the four-way valve 4.
[0044] The first tee piece 2-3 is provided with a first tapered joint 2-16, and the third pipeline 2-4 is provided with a third valve 2-17 and a second tapered joint 2-18.
[0045] like Figure 3 As shown, the hot gas bypass steel pipeline assembly 3 is composed of the ninth pipeline 3-1, the fourth elbow 3-2, the tenth pipeline 3-3, the fourth valve 3-4, the eleventh pipeline 3-5, the fifth elbow 3-6, the twelfth pipeline 3-7, the sixth elbow 3-8, the thirteenth pipeline 3-9 and the seventh elbow 3-10, which are spliced in sequence. The ninth pipeline 3-1 is connected to the second three-way piece 2-11, and the seventh elbow 3-10 is connected to the gas-liquid separator 10.
[0046] like Figure 5 As shown, the air intake steel pipeline assembly 7 is composed of the fourteenth pipeline 7-1, the fifth valve 7-2, the fifteenth pipeline 7-3, the eighth elbow 7-4, the sixteenth pipeline 7-5, the seventeenth pipeline 7-6, the ninth elbow 7-7, the third three-way piece 7-8, the eighteenth pipeline 7-9, the tenth elbow 7-10, and the nineteenth pipeline 7-11, which are sequentially spliced together. The fourteenth pipeline 7-1 is connected to the air intake port of the compressor 1, and the nineteenth pipeline 7-11 is connected to the gas-liquid separator 10.
[0047] The sixteenth pipeline 7-5 is provided with a third tapered joint 7-12, a fourth tapered joint 7-13 and a fifth tapered joint 7-14, and the fifth tapered joint 7-14 is used to connect with the shutdown bypass steel pipeline assembly 6.
[0048] like Figure 6 As shown, the intake bypass steel pipeline assembly 8 is composed of the eleventh elbow 8-1, the twentieth pipeline 8-2, the twenty-first pipeline 8-3, the twelfth elbow 8-4, the fourth three-way piece 8-5, the twenty-second pipeline 8-6, the twenty-third pipeline 8-7, the thirteenth elbow 8-8, the sixth valve 8-9, and the twenty-fourth pipeline 8-10, which are spliced in sequence. The eleventh elbow 8-1 is connected to the E port of the four-way valve 4, the twenty-second pipeline 8-6 is connected to the water-cooled heat exchanger 13, and the twenty-fourth pipeline 8-10 is connected to the third three-way piece 7-8.
[0049] Preferably, the first pipeline 2-1, the third pipeline 2-4, the fourth pipeline 2-6, the fifth pipeline 2-8, the sixth pipeline 2-10, the seventh pipeline 2-12, the eighth pipeline 2-14, the ninth pipeline 3-1, the tenth pipeline 3-3, the eleventh pipeline 3-5, the twelfth pipeline 3-7, the thirteenth pipeline 3-9, the fourteenth pipeline 7-1, the fifteenth pipeline 7-3, the sixteenth pipeline 7-5, the seventeenth pipeline 7-6, the eighteenth pipeline 7-9, the nineteenth pipeline 7-10, the twentieth pipeline 8-2, the twenty-first pipeline 8-3, the twenty-second pipeline 8-6, the twenty-third pipeline 8-7, and the twenty-fourth pipeline 8-10 are all straight steel pipes;
[0050] Among them, the first pipeline 2-1 is of DN40 specification, the third pipeline 2-4, the fourth pipeline 2-6, the fifth pipeline 2-8, and the sixth pipeline 2-10 are of DN50 specification, the eighth pipeline 2-14 is of DN65 specification, the ninth pipeline 3-1, the tenth pipeline 3-3, the eleventh pipeline 3-5, the twelfth pipeline 3-7, the thirteenth pipeline 3-9, the fourteenth pipeline 7-1, the fifteenth pipeline 7-3, the sixteenth pipeline 7-5, the seventeenth pipeline 7-6, the eighteenth pipeline 7-9, the nineteenth pipeline 7-11, the twentieth pipeline 8-2, the twenty-first pipeline 8-3, the twenty-second pipeline 8-6, the twenty-third pipeline 8-7, and the twenty-fourth pipeline 8-10 are of DN80 specification. The specific lengths can be determined according to different models and are not specifically limited in this embodiment.
[0051] Preferably, the second pipeline 2-2 and the seventh pipeline 2-12 are both seamless steel pipes with reducers, wherein the second pipeline 2-2 is a DN40 pipe diameter converted to a DN50 pipe diameter, and the seventh pipeline 2-12 is a DN50 pipe diameter converted to a DN65 pipe diameter;
[0052] Preferably, the first elbow 2-9, the second elbow 2-13, the third elbow 2-15, the fourth elbow 3-2, the fifth elbow 3-6, the sixth elbow 3-8, the seventh elbow 3-10, the eighth elbow 7-4, the ninth elbow 7-7, the tenth elbow 7-10, the eleventh elbow 8-1, the twelfth elbow 8-4, and the thirteenth elbow 8-8 are all 90° standard seamless steel pipe long elbows, among which the first elbow 2-9 is DN50, the second elbow 2-13 and the third elbow 2-15 are DN65, and the rest are DN80.
[0053] Preferably, the first valve 2-5 is a stop valve to prevent the refrigerant from flowing back to the compressor exhaust port during shutdown;
[0054] The second valve 2-7 and the fifth valve 7-2 are manual shut-off valves used for unit maintenance; the third valve 2-17 is a safety pressure relief valve used to protect the exhaust pipe high pressure from exceeding the limit; the fourth valve 3-4 is an electric ball valve used to bypass the hot gas of the centrifugal unit compressor during takeoff, balancing the high and low pressure differences and preventing unit surge; the sixth valve 8-9 is an electric butterfly valve used to bypass the four-way valve and gas-liquid separator during cooling to increase the unit's evaporation temperature;
[0055] Preferably, the first tee 2-3 is a reducing steel pipe tee, with DN40 at both ends turning into DN35 at the middle outlet; the second tee 2-11, the third tee 7-8, and the fourth tee 8-5 are all equal-diameter steel pipe tees, of which the second tee 2-11 is DN50, and the third tee 7-8 and the fourth tee 8-5 are DN80;
[0056] Preferably, the first tapered joint 2-16, the third tapered joint 7-12, and the fourth tapered joint 7-13 are all NPT1 / 4 interfaces. The first tapered joint 2-16 is used to install the high-pressure sensor, the third tapered joint 7-12 is used to install the cooling low-pressure sensor, the heating low-pressure sensor, the cooling low-pressure switch, and the heating low-pressure switch. The fourth tapered joint 7-13 is used to install the suction temperature sensor;
[0057] The second tapered joint 2-18 and the fifth tapered joint 7-14 are RC3 / 8 interfaces, which are used to install the exhaust temperature sensor and the shutdown bypass steel pipe assembly respectively.
[0058] Based on this unit, the following specific embodiments can be executed:
[0059] In the cooling mode, the high-temperature, high-pressure, superheated gaseous refrigerant discharged from the compressor 1 first enters the exhaust steel pipe assembly 2 through the first pipe 2-1, and then is discharged from the third elbow 2-15 of the exhaust steel pipe assembly into the four-way valve 4 for diversion and outflow, and then enters the manifold steel pipe assembly 5 for uniform distribution and enters the air-cooled heat exchanger 11 for condensation and heat dissipation, and then becomes a supercooled liquid refrigerant, and then flows through the throttle valve 12 to become a low-temperature, low-pressure gas-liquid two-phase refrigerant, and then enters the water-cooled heat exchanger 13 for evaporation and absorption. The heat of water is used to produce cold water. The refrigerant evaporates and absorbs heat in the water-cooled heat exchanger 13 to become a low-temperature and low-pressure superheated gaseous refrigerant. In the refrigeration mode, the sixth valves 8 and 9 of the intake bypass steel pipe assembly 8 are energized and are in the open state. The refrigerant will enter the intake bypass steel pipe assembly 8 from the twenty-second pipe 8 and 6, and then flow out from the twenty-fourth pipe 8 and 10, enter the intake steel pipe assembly 7 through the third three-way valve 7 and 8, and then return to the intake port of the compressor 1 from the fourteenth pipe 7 and 1, completing the refrigerant circulation of the entire main circulation loop.
[0060] Similarly, in the heating mode, the high-temperature and high-pressure superheated gaseous refrigerant discharged by the compressor 1 first enters the exhaust steel pipe assembly 2 from the first pipeline 2, 1, and then is discharged from the third elbow 2, 15 of the exhaust steel pipe assembly into the four-way valve 4 for turning and flowing out, and enters the intake bypass steel pipe assembly 8. At this time, the sixth valve 8-9 must be in the closed state, and the refrigerant therefore enters the water-cooled heat exchanger 13 through the twenty-second pipeline 8-6 of the intake bypass steel pipe assembly 8 to release heat to the cooling water, thereby producing hot water. The refrigerant is condensed into a medium-temperature and high-pressure supercooled liquid refrigerant in the water-cooled heat exchanger 13, and then flows out into the throttle valve 12 for throttling to become a low-temperature and low-pressure two-phase refrigerant, and then flows out into the air-cooled heat exchanger 11 for evaporation and heat absorption to become a low-temperature and low-pressure gaseous superheated refrigerant, and then converges into the manifold steel pipeline assembly 5 and returns to the four-way valve 4 to be diverted and flow into the low-pressure pipeline 9, and returns to the other inlet of the gas-liquid separator 10. The outlet of the gas-liquid separator 10 is connected to the nineteenth pipeline 7-11 of the intake steel pipeline assembly 7, and then under the action of the pressure difference, the main refrigerant returns from the fourteenth pipeline 7-1 to the intake port of the compressor 1, completing the refrigerant cycle of the entire main circulation loop.
[0061] In cooling / heating mode, the hot gas bypass circuit specifically bypasses some of the high-temperature, high-pressure gaseous refrigerant from the second tee 2-11 of the exhaust steel pipe assembly 2 of the main circulation loop and discharges it to the gas-liquid separator 10 for pressure relief, thereby controlling surge in the centrifugal unit. The outlet of the gas-liquid separator 10 is connected to the nineteenth pipe 7-11 of the intake steel pipe assembly 7. Then, under the influence of the pressure differential, this bypassed gaseous refrigerant returns to the return air port of the compressor 1, completing the hot gas bypass cycle.
[0062] When the unit needs to shut down, the solenoid valve in the shutdown bypass steel pipe assembly 6 is first opened. At this time, the high-temperature and high-pressure gaseous refrigerant will be discharged from the first three-way piece 2-3 of the exhaust steel pipe assembly 2 into the shutdown bypass steel pipe assembly 6. Under the action of the high and low pressure difference, a large amount of gaseous refrigerant returns to the compressor suction port from the fifth tapered joint 7-14 of the intake steel pipe assembly 7 to complete the pressure relief.
[0063] Specifically, in the defrost mode, since the compressor speed of general variable frequency centrifugal air-cooled heat pump units is relatively high, usually reaching 25000rpm~100000rpm, it is impossible to directly switch the four-way valve to perform refrigeration mode defrosting like traditional scroll / screw compressors. It is necessary to shut down the unit first, and then start the four-way valve 4 without power. The unit performs a refrigeration cycle, and the high-temperature and high-pressure gaseous refrigerant flows through the exhaust steel pipe assembly 2, the four-way valve 4, and the manifold steel pipe assembly 5 in turn to enter the air-cooled heat exchanger 11 for defrosting. Unlike the refrigeration mode, in the defrost mode, the sixth valve 8-9 of the suction bypass steel pipe assembly 8 cannot be powered, because there will be a large amount of liquid refrigerant in the main circulation loop during defrosting. If the gas-liquid separator 10 is bypassed, the compressor 1 will inhale liquid and damage the compressor. In defrost mode, the refrigerant in the main circulation loop is discharged from the air pipe of water-cooled heat exchanger 13, flows through the suction bypass steel pipe assembly 8, four-way valve 4, low-pressure pipe 9, gas-liquid separator 10, and suction steel pipe assembly 7, and returns to the suction port of compressor 1, completing the entire defrost cycle. When the defrost is completed, compressor 1 is shut down again, and then the restart command is executed again. Four-way valve 4 is energized to switch to heating mode.
[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.
[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A steel piping assembly for a variable frequency centrifugal air-cooled heat pump unit, comprising a compressor, a four-way valve, a gas-liquid separator, an air-cooled heat exchanger, and a water-cooled heat exchanger, arranged on a bottom frame of the unit, characterized in that: The exhaust port of the compressor is connected to the D port of the four-way valve through an exhaust steel pipeline assembly. A hot gas bypass steel pipeline assembly is led out of the exhaust steel pipeline assembly near the air outlet and is connected to the gas-liquid separator. The air intake of the compressor is connected to the gas-liquid separator through an air intake steel pipeline assembly. The shutdown bypass steel pipeline assembly is led out from the air inlet of the exhaust steel pipeline assembly and leads to the air outlet of the air intake steel pipeline assembly. The C port of the four-way valve is connected to a plurality of the air-cooled heat exchangers through a centralized steel pipeline assembly, and the plurality of the air-cooled heat exchangers are connected to the water-cooled heat exchanger after being centralized. The water-cooled heat exchanger is respectively connected to the intake steel pipeline assembly and the E port of the four-way valve through an intake bypass steel pipeline assembly; The S port of the four-way valve is connected to the inlet of the gas-liquid separator through a low-pressure steel pipeline component.
2. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 1, characterized in that: The exhaust steel pipeline assembly is composed of a first pipeline, a second pipeline, a first tee, a third pipeline, a first valve, a fourth pipeline, a second valve, a fifth pipeline, a first elbow, a sixth pipeline, a second tee, a seventh pipeline, a second elbow, an eighth pipeline and a third elbow, which are sequentially spliced together. The first pipeline is connected to the exhaust port of the compressor, and the third elbow is connected to the D port of the four-way valve. The first three-way piece is provided with a first tapered joint, and the third pipeline is provided with a third valve and a second tapered joint.
3. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 2, characterized in that: The hot gas bypass steel pipeline assembly is composed of the ninth pipeline, the fourth elbow, the tenth pipeline, the fourth valve, the eleventh pipeline, the fifth elbow, the twelfth pipeline, the sixth elbow, the thirteenth pipeline and the seventh elbow, which are spliced in sequence. The ninth pipeline is connected to the second tee piece, and the seventh elbow is connected to the gas-liquid separator.
4. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 3, characterized in that: The air intake steel pipeline assembly is composed of a fourteenth pipeline, a fifth valve, a fifteenth pipeline, an eighth elbow, a sixteenth pipeline, a seventeenth pipeline, a ninth elbow, a third tee, an eighteenth pipeline, a tenth elbow, and a nineteenth pipeline, which are sequentially spliced together. The fourteenth pipeline is connected to the air intake port of the compressor, and the nineteenth pipeline is connected to the gas-liquid separator. The sixteenth pipeline is provided with a third tapered joint, a fourth tapered joint and a fifth tapered joint.
5. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 4, characterized in that: The intake bypass steel pipeline assembly is composed of the eleventh elbow, the twentieth pipeline, the twenty-first pipeline, the twelfth elbow, the fourth three-way piece, the twenty-second pipeline, the twenty-third pipeline, the thirteenth elbow, the sixth valve, and the twenty-fourth pipeline, which are spliced in sequence. The eleventh elbow is connected to the E port of the four-way valve, the twenty-second pipeline is connected to the water-cooled heat exchanger, and the twenty-fourth pipeline 8-10 is connected to the third three-way piece.
6. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 5, characterized in that: The first pipeline, the third pipeline, the fourth pipeline, the fifth pipeline, the sixth pipeline, the seventh pipeline, the eighth pipeline, the ninth pipeline, the tenth pipeline, the eleventh pipeline, the twelfth pipeline, the thirteenth pipeline, the fourteenth pipeline, the fifteenth pipeline, the sixteenth pipeline, the seventeenth pipeline, the eighteenth pipeline, the nineteenth pipeline, the twentieth pipeline, the twenty-first pipeline, the twenty-second pipeline, the twenty-third pipeline, and the twenty-fourth pipeline are all straight steel pipes; The second pipeline and the seventh pipeline are both seamless steel pipes with reducer joints, wherein the second pipeline is a DN40 specification converted to a DN50 specification, and the seventh pipeline is a DN50 specification converted to a DN65 specification.
7. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 5, characterized in that: The first elbow, the second elbow, the third elbow, the fourth elbow, the fifth elbow, the sixth elbow, the seventh elbow, the eighth elbow, the ninth elbow, the tenth elbow, the eleventh elbow, the twelfth elbow and the thirteenth elbow are all 90° seamless steel pipe long elbows, among which the first elbow is DN50, the second elbow and the third elbow are DN65, and the rest are DN80.
8. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 5, characterized in that: The first valve is a stop valve, the second valve and the fifth valve are manual shut-off valves, the third valve is a safety pressure relief valve, the fourth valve is an electric ball valve, and the sixth valve is an electric butterfly valve.
9. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 5, characterized in that: The first tee is a reducing steel pipe tee, with DN40 specifications at both ends changing to DN35 specifications at the middle outlet. The second, third and fourth tees are all equal-diameter steel pipe tees, among which the second tee is DN50 specifications, and the third and fourth tees are DN80 specifications.
10. The steel pipe assembly of a variable frequency centrifugal air-cooled heat pump unit according to claim 5, characterized in that: The first, third and fourth tapered joints are all NPT1 / 4 interfaces. The first tapered joint is used to install the high-pressure sensor, the third tapered joint is used to install the cooling low-pressure sensor, the heating low-pressure sensor, the cooling low-pressure switch, and the heating low-pressure switch, and the fourth tapered joint is used to install the suction temperature sensor; The second tapered joint and the fifth tapered joint are RC3 / 8 interfaces, which are used to install the exhaust temperature sensor and the shutdown bypass steel pipe assembly respectively.