Novel manifold and refrigeration apparatus

Abstract

The application provides a new type of manifold, which comprises a main pipe, a first branch pipe and a second branch pipe, the second branch pipe comprises an extrusion section and an extension section welded to the extrusion section, the extrusion section and the first branch pipe extend to two sides of the main pipe respectively, the extrusion section, the main pipe and the first branch pipe are integrally formed and are communicated with each other through a communication area; the number of circular bends on the first branch pipe and the second branch pipe is the same. Wherein, the axial lines of the first branch pipe and the extrusion section close to the communication area respectively intersect with the axial line of the main pipe close to the communication area at a reference point and respectively form two angles, the two angles constitute the bending angle of the first branch pipe and the extrusion section; the bending angle is 40°≤β≤160° and both of the two angles are greater than 10°, the vertical height difference ΔH between the end faces of the two branch pipes is less than or equal to 53mm; wherein the basic size B of the length of one branch pipe is related to the bending angle, the center distance of the two branch pipe ends and the outer diameter of the first branch pipe close to the communication area, and the basic size offset ΔB is less than or equal to 44.5mm.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of refrigeration system accessories, and particularly relates to a new type of branch pipe and a refrigeration equipment. BACKGROUND

[0002] Multi-connected air conditioning (heat pump) system is a direct evaporation air conditioning system composed of one or several outdoor units and several indoor units connected and installed on site with specified pipes. In the multi-connected air conditioning (heat pump) unit, a special branch pipe with the functions of splitting or combining is needed to connect the pipes to realize the distribution of refrigerant in the pipes. Although the branch pipe is similar to the tee but different from the tee pipe, first, the three connecting ends of the tee pipe are very short, and the ratio of the length of each connecting end to its own outer diameter is below 2 times, so it is easy to be extruded into shape, but the three connecting ends are very short, and if it is directly welded with the pipe of the multi-connected air conditioning (heat pump) system, the heat transfer will easily cause the secondary melting of the weld and result in leakage. In addition, since the port sizes of the three connecting ends of the tee pipe are fixed, it cannot be connected with the pipes of various sizes on the air conditioning system. As an important connecting part of the multi-connected air conditioning (heat pump) system, the three connecting ends of the branch pipe are not only long but also have several ports of different specifications to meet the connection needs of pipes of different specifications of air conditioners of different powers.

[0003] A traditional branch pipe structure is welded by a tee pipe and three extension pipes (as shown in Figure 1 ), so there are three welds 101, 102 and 103. The three extension pipes welded on the tee part make this type of branch pipe have problems of too many welds, high leakage risk, waste of copper material and high manufacturing cost. To reduce the welds on the branch pipe, someone proposes a branch pipe structure with two welds, in which an interface 102' is formed on the side wall of the manifold, one branch pipe is connected to the end 101' of the manifold, and the other branch pipe is connected to the interface 102' on the side wall of the manifold, as shown in Figure 2 . Compared with Figure 1 this structure, Figure 2 although the number of welds is reduced by one, the interface between the branch pipe and the side wall of the manifold in this structure is not only difficult to weld, easy to leak at the welded part, but also easy to fall off after welding.

[0004] To solve the problem of many complaints about leakage of the branch pipe with three welds mainly composed of a tee pipe on the market, the applicant proposes a branch pipe with an integrally formed pipe body after extrusion in the patent CN208282360U (as shown in Figure 3The branch pipes are integrated and have a length sufficient to meet the pipe connection requirements of the multi-connected air conditioner (heat pump) system, so that the product has less welds, simple structure and high safety. However, the branch pipe of this structure has problems of uneven refrigerant distribution and excessive pressure drop between the main pipe and the branch pipe in actual installation and use, which not only causes the indoor unit to have reduced refrigeration power but also affects the system energy efficiency ratio. Therefore, as a connecting pipe for realizing the distribution or combination of refrigerant in the pipe, the branch pipe not only needs to meet the system pressure requirement and be easy to install but also needs to have uniform distribution and small flow resistance. SUMMARY

[0005] In order to overcome the shortcomings of the prior art, the present application provides a novel branch pipe with two branch pipes having good distribution uniformity and small input and output pressure drop and a refrigeration equipment.

[0006] In order to achieve the above-mentioned purpose, the present application provides a novel branch pipe, which comprises a main pipe, a first branch pipe and a second branch pipe, the second branch pipe comprises an extruded section and an extended section welded to the extruded section, the extruded section and the first branch pipe extend to two sides of the main pipe respectively, the extruded section, the main pipe and the first branch pipe are integrally formed and are communicated with each other through a communication area; the length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the communication area, the length of at least one of the two branch pipes is greater than four times the outer diameter of the first branch pipe near the communication area, and the number of circular bends on the first branch pipe and the second branch pipe is the same.

[0007] The axis lines of the first branch pipe and the extruded section near the communication area intersect with the axis line of the main pipe near the communication area at a reference point and form two angles, and the two angles constitute the bending angle of the first branch pipe and the extruded section; the bending angle is 40°≤β≤160° and both of the two angles are greater than or equal to 10°, and the vertical height difference ΔH between the end faces of the two branch pipes is less than or equal to 53mm; the basic size B of the length of one of the branch pipes is related to the bending angle, the center distance between the ends of the two branch pipes and the outer diameter of the first branch pipe near the communication area, and the basic size offset ΔB is less than or equal to 44.5mm; the length of the main pipe refers to the vertical distance from the end face of the main pipe to the section where the reference point is located, and the length of the branch pipe refers to the vertical distance from the end face of the branch pipe to the section where the reference point is located.

[0008] According to an embodiment of the present application, the basic size B of the length of one of the branch pipes is negatively related to the bending angle and the center distance between the ends of the two branch pipes respectively and is positively related to the outer diameter of the first branch pipe near the communication area.

[0009] According to an embodiment of the present application, the basic size B of the length of one of the branch pipes and the outer diameter D of the first branch pipe near the communication area, the bending angle β and the center distance L between the ends of the two branch pipes satisfy the following relationship:

[0010]

[0011] wherein K is a pressure drop difference coefficient related to a critical value of drop ratio δV of flow rate of two branch pipes to flow rate of end of main pipe specified by air conditioner manufacturer; and g is gravity acceleration.

[0012] According to an embodiment of the present application, the pressure drop difference coefficient K satisfies: 1.2≤K≤1.55.

[0013] According to an embodiment of the present application, the basic size offset ΔB is positively related to the outer diameter of the first branch pipe at the proximity communication area and negatively related to the center distance of the two branch pipe ends.

[0014] According to an embodiment of the present application, the basic size offset ΔB satisfies the following relationship:

[0015]

[0016] wherein D is the outer diameter of the first branch pipe at the proximity communication area, and L is the center distance of the two branch pipe ends.

[0017] According to an embodiment of the present application, the maximum and minimum values of the bending angle β between the first branch pipe and the extrusion section are respectively related to the outer diameter D of the first branch pipe at the proximity communication area and the center distance L of the two branch pipe ends; wherein:

[0018]

[0019]

[0020] wherein β min is the lower limit threshold of the bending angle β, and β max is the upper limit threshold of the bending angle β, and g is gravity acceleration.

[0021] According to an embodiment of the present application, the vertical height difference ΔH between the two branch pipe end faces is related to the ratio between the outer diameter D of the first branch pipe at the proximity communication area and the center distance L of the two branch pipe ends, and the vertical height difference ΔH between the two branch pipe end faces satisfies:

[0022] ΔH=45+L / D.

[0023] According to an embodiment of the present application, the number of circular bends on the first branch pipe and the second branch pipe is one, and at least one of the axial center lines of the two branch pipe ends is parallel to the axial center line of the main pipe at the proximity communication area.

[0024] According to an embodiment of the present application, the main pipe, the first branch pipe and the second branch pipe are all copper pipes;

[0025] Or, the main pipe, the first branch pipe and the second branch pipe are all stainless steel pipes, and the extension section is a copper pipe; the novel branch pipe further comprises a main pipe connecting section made of copper and welded to the main pipe, and a first branch pipe connecting section made of copper and welded to the end of the first branch pipe;

[0026] Or, the main pipe, the first branch pipe and the second branch pipe are all stainless steel pipes, and the novel branch pipe further comprises a main pipe connecting section made of copper and welded to the main pipe, a first branch pipe connecting section made of copper and welded to the first branch pipe, and a second branch pipe connecting section made of copper and welded to the extension section of the second branch pipe.

[0027] According to an embodiment of the present application, the perpendicular distance between the axis of the end of the first branch pipe and the axis of the main pipe near the communication region is 1.3D≤L1≤4D, wherein D is the outer diameter of the first branch pipe near the communication region.

[0028] In another aspect, the present application also provides a novel branch pipe, which comprises a main pipe, a first branch pipe and a second branch pipe. The main pipe comprises a main pipe interface section and a main pipe body which are welded together. The first branch pipe is connected to the main pipe interface section and extends to one side of the main pipe interface section. The second branch pipe comprises an extrusion section and an extension section which is welded to the extrusion section, the extrusion section is connected to the main pipe interface section and extends to the other side of the main pipe interface section, and the extrusion section, the first branch pipe and the main pipe interface section are integrally formed and communicate with each other through a communication region. The length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the communication region, and the length of at least one of the two branch pipes is greater than four times the outer diameter of the first branch pipe near the communication region. The number of circular bends on the first branch pipe and the second branch pipe is the same. The axis of the first branch pipe near the communication region and the axis of the extrusion section near the communication region intersect at a reference point and form two angles, respectively, and the two angles constitute the bending angle of the first branch pipe and the extrusion section. The bending angle is 40°≤β≤160°, and both angles are greater than or equal to 10°. The vertical height difference between the end faces of the two branch pipes is ΔH≤53mm. The basic dimension B of the length of one of the branch pipes is related to the bending angle, the center distance between the ends of the two branch pipes and the outer diameter of the first branch pipe near the communication region, and the basic dimension offset ΔB≤44.5mm. The length of the main pipe refers to the vertical distance from the end face of the main pipe body to the section where the reference point is located, and the length of the branch pipe refers to the vertical distance from the end face of the branch pipe to the section where the reference point is located.

[0029] According to an embodiment of the present application, the basic dimension B of the length of one of the branch pipes is negatively related to the bending angle and the center distance between the ends of the two branch pipes, respectively, and is positively related to the outer diameter of the first branch pipe near the communication region. The basic dimension B satisfies:

[0030]

[0031] Wherein, D is the outer diameter of the first branch pipe near the communication zone; β is the bending angle; L is the center distance of the two branch pipe ends; K is the pressure drop difference coefficient related to the critical value of the drop ratio δV of the flow rate of the two branch pipes to the flow rate of the main pipe; g is the acceleration of gravity.

[0032] In another aspect, the present application also provides a new type of branch pipe, which comprises a main pipe, a first branch pipe and a second branch pipe, the second branch pipe comprising an extrusion section and an extension section welded to the extrusion section, the extrusion section and the first branch pipe extending to two sides of the main pipe respectively, the extrusion section, the main pipe and the first branch pipe being integrally formed and communicating with each other through a communication zone; the included angle between the axis of the end of the extension section and the axis of the main pipe near the communication zone is 80°≤θ≤100°; the length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the communication zone, and the length of the first branch pipe is greater than four times the outer diameter of the first branch pipe near the communication zone.

[0033] Wherein, the number of circular bends on the first branch pipe and the second branch pipe is the same, and the circular bends on the second branch pipe are located on the extension section, the axes of the first branch pipe and the extrusion section near the communication zone intersect with the axis of the main pipe near the communication zone at a reference point and form two angles respectively, and the two angles constitute the bending angle of the first branch pipe and the extrusion section; the bending angle is 40°≤β≤160°, and both angles are greater than or equal to 10°; the basic dimension B of the length of the first branch pipe is negatively related to the bending angle and the transverse distance between the axis of the first branch pipe and the extended end of the circular bend on the extension section, and is positively related to the outer diameter of the first branch pipe near the communication zone, and the offset amount ΔB of the basic dimension is ≤44.5mm; the length of the main pipe refers to the vertical distance from the end face of the main pipe to the section where the reference point is located, and the length of the first branch pipe refers to the vertical distance from the end face of the first branch pipe end to the section where the reference point is located.

[0034] In another aspect, the present application also provides a refrigeration equipment comprising the above-mentioned new type of branch pipe.

[0035] In summary, the new manifold provided by the application introduces the number of round bends, the angle of the angle, and the offset of the length of the branch pipe relative to the basic size of the length to control the difference of the local resistance loss between the two branch pipes based on the bending angle between the two branch pipes; at the same time, by controlling the vertical height difference between the end faces, the influence of the difference of the flow resistance between the two branch pipes is further reduced, and the control of the uniformity of the two branch pipes is realized. As for the pressure drop between the input and the output, the length of the branch pipe is accurately controlled based on the outer diameter of the first branch pipe close to the communication zone, the bending angle, and the center distance of the two branch pipe ends, so that the length of the two branch pipes meets the installation requirements, and the resistance loss of the whole product meets the requirements of the system pressure drop. The accurate setting of multiple parameters between the two branch pipes in the new manifold provided by the application not only has excellent uniformity of the two branch pipes, but also greatly reduces the pressure drop between the input and the output, so that the multi-connected air conditioner (heat pump) system has a higher energy efficiency ratio.

[0036] In order to make the above and other objects, features and advantages of the present application more apparent, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 、 Figure 2 and Figure 3 The structure schematic diagram of the existing manifold is shown.

[0038] Figure 4 The structure schematic diagram of the new manifold provided by the embodiment one of the present application is shown.

[0039] Figure 5 The structure schematic diagram of the main pipe, the first branch pipe and the extrusion section after integrated molding is shown. Figure 4

[0040] Figure 6 The structure schematic diagram of the new manifold provided by another embodiment of the present application is shown.

[0041] Figure 7 The structure schematic diagram of the basic size changing with the angle α1 is shown.

[0042] Figure 8 The structure schematic diagram of the heat preservation sleeve installation is shown.

[0043] Figure 9 and Figure 10 The structure schematic diagram of the new manifold provided by another embodiment of the present application is shown.

[0044] Figure 11 The structure schematic diagram of the new manifold provided by the embodiment two of the present application is shown.

[0045] Figure 12 ​The diagram shown is a structural schematic of the novel branch pipe provided in Embodiment 3 of the present invention. Detailed Implementation

[0046] To improve the uniformity of refrigerant flow between the two branch pipes in existing manifolds, current methods primarily focus on controlling the angle distribution between them. However, it has been proven that even symmetrically distributed branch pipes cannot achieve uniform flow. Furthermore, based on the energy efficiency ratio (EER) of multi-split air conditioning (heat pump) units, which limits energy loss in the piping, the manifold, as the main connecting pipe, needs to be designed to account for the total energy loss of refrigerant as it passes through. However, existing manifold designs do not consider the impact of this factor.

[0047] To balance the uniformity of refrigerant flow between the two branches of the manifold and the total energy loss of refrigerant flowing through the manifold, this embodiment provides a novel manifold. For example... Figure 4 As shown, the new type of branch pipe includes a main pipe 1, a first branch pipe 2, and a second branch pipe 3. The second branch pipe 3 includes an extruded section 31 and an extension section 32 welded to the extruded section 31. The extruded section 31 and the first branch pipe 2 extend to both sides of the main pipe 1, respectively. The extruded section 31, the main pipe 1, and the first branch pipe 2 are integrally formed and interconnected through a connecting area 100. The length Ha of the main pipe 1 is greater than or equal to twice the outer diameter D of the first branch pipe 2 near the connecting area. At least one of the two branch pipes has a length greater than four times the outer diameter D of the first branch pipe 2 near the connecting area. The number of round bends Re on the first branch pipe 2 and the second branch pipe 3 is the same.

[0048] In this embodiment, the centerlines of the first branch pipe 2 and the extrusion section 31 near the connecting area 100 intersect the centerline of the main pipe 1 near the connecting area 100 at reference point O, forming two bisector angles α1 and α2 respectively. The two bisector angles constitute the bending angle β of the first branch pipe 2 and the extrusion section 31. The bending angle is 40°≤β≤160° and both bisector angles are greater than or equal to 10°. The vertical height difference ΔH between the end faces of the two branch pipes is ≤53mm. The basic dimension B of the length of one branch pipe is related to the bending angle, the center distance between the ends of the two branch pipes, and the outer diameter of the first branch pipe near the connecting area, and the basic dimension offset ΔB≤44.5mm. In the novel branch pipe provided in this embodiment, the direction of refrigerant output from the two branch pipes is basically parallel to the direction of refrigerant entering the main pipe 1. The length Ha of the main pipe 1 refers to the vertical distance from the end face of the main pipe to the cross section where reference point O is located. The lengths Hb and Hc of the two branch pipes refer to the vertical distance from the end face of the branch pipe to the cross section where reference point O is located.

[0049] Specifically, in the present embodiment, when the basic dimension B of one of the two branch pipes (either the first branch pipe or the second branch pipe) is determined based on the outer diameter D of the first branch pipe near the communication zone, the bending angle β, and the center distance L between the two branch pipe ends, the length of the branch pipe can vary within the range of B~B+ΔB or B-ΔB~B; and the length range of the other branch pipe can be determined based on the vertical height difference ΔH between the two branch pipe end faces.

[0050] The flow distribution uniformity refers to the uniformity of the flow rates of the two branch pipes. In the case where the inner diameters of the two branch pipes are substantially the same, the flow uniformity between the two branch pipes is embodied in the form of the flow rates of the refrigerant, i.e., the relationship between the flow rate Vb of the first branch pipe 2 and the flow rate Vc of the second branch pipe 3, according to the relationship Q=V*S (Q is the flow rate, V is the flow rate of the refrigerant, and S is the flow passage cross-sectional area of the pipe). The change in the flow rate of the refrigerant during the delivery of the refrigerant is related to the pipe resistance, which includes the frictional resistance representing the resistance to flow within the fluid and the local resistance representing the turbulent disturbance. Therefore, to improve the flow distribution uniformity between the two branch pipes, the resistance losses on the two branch pipes need to be studied to make the two as close as possible. As for the total energy loss of the refrigerant during the flow process, the energy loss is also caused by the losses of the frictional resistance and the local resistance, which is manifested as the drop difference (also referred to as the pressure drop) between the flow rate Va at the end of the main pipe and the flow rates Vb and Vc of the two branch pipes.

[0051] As analyzed above, in the case where the flow rate Va at the end of the main pipe is determined, both the flow distribution uniformity between the two branch pipes and the total energy loss of the refrigerant flowing through the new diverging pipe can be embodied by the flow rates Vb and Vc of the two branch pipes; and the change in the flow rate of the refrigerant on each branch pipe is mainly affected by the local resistance loss and the frictional resistance loss on the branch pipe. Therefore, the structure of the new diverging pipe provided in the present example will be described in detail from the two aspects of the resistance losses.

[0052] For the local resistance loss, the bending angle β between the first branch pipe 2 and the extrusion section 31 extending to two sides of the main pipe 1 respectively will cause a local loss. In addition, the axis lines of the first branch pipe 2 and the second branch pipe 3 are parallel to the axis line of the main pipe 1 near the communication area 100, which will cause a circular bend Re on each of the two branch pipes. At the circular bend Re, the particles in the refrigerant will be affected by the centrifugal force to generate a vortex, thereby causing a local loss. When the number of circular bends on the two branch pipes is different, such as one of the branch pipes has one circular bend and the other branch pipe has more than two circular bends, the local disturbance between the circular bends will interfere with each other and cause greater resistance, which not only has poor uniformity of the flow distribution but also seriously affects the pressure drop difference of the branch pipe. Based on this preliminary analysis, in order to make the local resistance on the two branch pipes close and as far as possible to reduce the influence of the local resistance on the pressure drop difference, the number of circular bends Re on the two branch pipes is set to one. However, the present application does not make any limitation in this regard. In other embodiments, based on the installation requirements, when more than two circular bends are needed on one of the branch pipes, in order to match the uniformity of the flow distribution, the same number of circular bends is arranged on the other branch pipe and the adjacent circular bends are spaced apart by a certain distance to as far as possible to reduce the mutual disturbance between them.

[0053] Based on the number of circular bends Re, in order to find the relationship between the bending angle β between the two flow distribution branch pipes and the uniformity of the flow distribution, the inventors have done a lot of experiments to study the change of the flow rate of the two branch pipes when the bending angle β of each specification of the new branch pipe changes. For a certain bending angle β, although the two branch angles α1, α2 are not necessarily equal, under the same conditions, the two branch angles are equal, which has the optimal uniformity of the flow distribution (the research later also proves that the change of the two branch angles has a smaller influence on the uniformity of the flow distribution within the range of the upper and lower critical angles, but the uniformity of the flow distribution is still optimal when α1 = α2). Therefore, in order to simplify the research object, in Table 1, the length Hb of the first branch pipe 2 under the condition that the two branch angles are equal is defined as the basic size B to study the influence of the bending angle β on the uniformity of the flow distribution, which is represented by Hb(B) in Table 1. However, the present application does not limit the actual length of the first branch pipe to be necessarily the basic size; in fact, the actual length of the first branch pipe is based on the basic size and has a deviation ΔB. Alternatively, in other embodiments, the length of the second branch pipe can also be determined according to the basic size B and the deviation ΔB, and then the length of the first branch pipe is determined based on ΔH.

[0054] The experimental conditions are as follows: the test sample is horizontally placed in an indoor environment of 18 degrees Celsius, the working pressure is set to 2.2 Mpa, corresponding test measuring instruments are installed on the two branch pipes to measure the refrigerant flow rate; the refrigerant with a flow rate of Va=5.13036 m / s and a model of R410A is input from the end of the main pipe 1; after stable operation for 30 minutes, the refrigerant flow rates at the output ends of the two branch pipes are collected for four times at equal time intervals, and the arithmetic average of the four collected data is taken as the test measurement value of the working condition. Based on the recorded refrigerant flow rates Vb and Vc of the first branch pipe 2 and the second branch pipe 3, the flow rate difference rate ΔV=(Vb-Vc) / Vb between the two branch pipes and the flow rate drop ratio δV=max(Vb / Va, Vc / Va) of the two branch pipes relative to the end flow rate of the main pipe are calculated.

[0055] Selection of the test sample: six test groups are selected according to the outer diameter D of the first branch pipe 2 close to the communication area 100, and a plurality of sub-test groups are formed in each test group according to the center distance between the ends of the two branch pipes; and a plurality of test samples are further formed in each sub-test group according to the bending angle β between the two branch pipes.

[0056] In the first test group, the outer diameter D=9.52 mm; in the five sub-test groups contained therein, the center distance L=46 mm, 51 mm, 56 mm, 61 mm, and 66 mm; and in each sub-test group, 24 test groups are divided according to the bending angle β between the two branch pipes.

[0057] In the second test group, the outer diameter D=15.88 mm; in the five sub-test groups contained therein, the center distance L=52 mm, 57 mm, 62 mm, 67 mm, and 72 mm; and in each sub-test group, 24 test groups are divided according to the bending angle β between the two branch pipes.

[0058] In the third test group, the outer diameter D=25 mm; in the four sub-test groups contained therein, the center distance L=67 mm, 77 mm, 87 mm, and 97 mm; and in each sub-test group, 24 test groups are divided according to the bending angle β between the two branch pipes.

[0059] In the fourth test group, the outer diameter D=38 mm; in the four sub-test groups contained therein, the center distance L=85 mm, 95 mm, 105 mm, and 115 mm; and in each sub-test group, 24 test groups are divided according to the bending angle β between the two branch pipes.

[0060] In the fifth test group, the outer diameter D=44 mm; in the four sub-test groups contained therein, the center distance L=100 mm, 110 mm, 120 mm, 130 mm, and 140 mm; and in each sub-test group, 24 test groups are divided according to the bending angle β between the two branch pipes.

[0061] The sixth test group has an outer diameter D = 54 mm; the five sub-test groups contained therein have a center distance L = 150 mm, 165 mm, 180 mm, 195 mm, and 210 mm; and each sub-test group is divided into 24 test groups according to the bending angle β between the two branch pipes.

[0062] The above six test groups were tested and the relevant data were recorded to form Table 1. After analyzing the data in Table 1, it was found that when 40°≤β≤160° and the vertical height difference ΔH between the end faces of the two branch pipes is ≤52 mm, the flow rate difference rate AV between the two branch pipes performs excellently. The same condition test Figure 3 The uniformity of the existing bifurcated pipe shown in Table 5 can only reach 40%, i.e., when 40°≤β≤160° and the vertical height difference ΔH between the end faces of the two branch pipes is ≤52 mm, the flow distribution uniformity of the new bifurcated pipe provided in the embodiment is much better than that of the existing bifurcated pipe.

[0063] After further analyzing the data that meet the requirement of flow distribution uniformity, it was found that the size Hb (i.e., the basic size B) of the first branch pipe 2 is related to the drop ratio δV of the flow rate of the two branch pipes relative to the flow rate at the end of the main pipe. Specifically, when the drop ratio δV of the flow rate of the two branch pipes relative to the flow rate at the end of the main pipe meets the critical value (the critical value in Table 1 is δV = 80%), the basic size B (i.e., the maximum basic size that meets the drop ratio δV) decreases with the increase of the bending angle β and the center distance L of the two branch pipe ends and increases with the increase of the outer diameter D of the first branch pipe 2 near the communication zone 100; i.e., the basic size B of the length of one branch pipe is negatively related to the bending angle and the center distance of the two branch pipe ends and is positively related to the outer diameter of the first branch pipe near the communication zone.

[0064] Specifically, when the outer diameter D and the center distance L are determined, the increase of the bending angle β will reduce the basic size B that meets the critical value of the drop ratio δV. In other words, when the bending angle β is increased, the basic size B of the new type of branch pipe needs to be controlled to reduce the resistance loss along the way, so that the drop ratio δV of the flow rate of the two branch pipes relative to the flow rate of the main pipe end is within the critical value to meet the requirements. The critical value of the drop ratio δV of the flow rate of the two branch pipes relative to the flow rate of the main pipe end in the air conditioning system is usually specified by the air conditioning manufacturer; and the basic size B also needs to meet certain length requirements due to the limitation of the machining of the round bend on the branch pipe and the assembly of the branch pipe and the external pipeline. For example, if the air conditioning manufacturer requires that the drop ratio δV of the new type of branch pipe be less than 20% and the basic size B be greater than 120 mm, for this sub-experimental group (the first sub-experimental group in the first experimental group in Table 1) with D = 9.52 mm and L = 46 mm, although the flow uniformity of the two branch pipes is also excellent when β = 105° and 115°, the flow rate difference rate ΔV ≤ 15%, but at this time the maximum basic size Hb (B) of the two branch pipes cannot meet the requirements of the critical value of the drop ratio δV and the length requirement of 120 mm, so under this condition, the maximum value of β can only be selected as 100°. When β = 100°, the basic size that meets the critical value of the drop ratio δV is 123.8 mm, that is, when the basic size of the new type of branch pipe is between 120 mm and 123.8 mm, not only the flow uniformity is excellent, but also the basic size length and the drop ratio δV can meet the requirements of the air conditioning manufacturer.

[0065] When the outer diameter D and the bending angle β of the first branch pipe 2 near the communication area 100 are determined, the increase of the center distance L of the two branch pipe ends will increase the refrigerant flow distance from the round bend Re on the two branch pipes to the reference point; in order to compensate for the resistance loss caused by the increase of the distance, the basic size also needs to be controlled to meet the requirements of the drop ratio δV. As shown in the first sub-experimental group and the second sub-experimental group in the first experimental group in Table 1, when D = 9.52 mm and β = 45°, if the center distance L of the two branch pipe ends is increased from 46 mm to 51 mm, the basic size that meets the critical value of the drop ratio δV needs to be adjusted from 151.42 mm to 149.06 mm.

[0066] On the contrary, when the distance L and the bending angle β are fixed, the increase of the outer diameter D of the first branch pipe 2 near the communicating area 100 will reduce the flow resistance of the refrigerant, so that the overall resistance of the branch pipe will become smaller. Therefore, the basic size B satisfying the critical value of the drop ratio δV can become higher, i.e. the adjustment range of the basic size will be larger. As shown in the fourth and fifth sub-test groups in the first test group in Table 1, when L = 67 mm and β = 50°, if the outer diameter D of the first branch pipe 2 near the communicating area 100 increases from 15.88 mm to 25 mm, the basic size satisfying the critical value of the drop ratio δV can increase from 149.95 mm to 180.45 mm. If the air conditioner manufacturer requires that the basic size of the branch pipe is greater than 120 mm, at this time the basic size can be adjusted between 120 mm and 180.45 mm according to other requirements, including manufacturing process requirements and external pipe connection requirements, such as the length of the expansion / contraction section or the depth of the socket insertion.

[0067] The analysis of the above experimental data can only preliminarily give a certain variation rule among the basic size B, the outer diameter D of the first branch pipe 2 near the communicating area 100, the distance L between the ends of the two branch pipes, and the bending angle β between the two branch pipes, but cannot give a specific relationship to accurately guide the design of the new type of branch pipe. Therefore, the inventors further analyze and fit the test data of the test pieces (the data marked in gray in Table 1) in which 40°≤β≤160° and the flow rate difference ratio AV and the drop ratio δV both meet the set requirements, so as to obtain the relationship among the basic size B, the outer diameter D of the first branch pipe 2 near the communicating area, the distance L between the ends of the two branch pipes, and the bending angle β between the two branch pipes, which will satisfy the following formula:

[0068]

[0069] wherein K is a pressure drop difference coefficient related to the critical value of the drop ratio δV of the flow rate of the two branch pipes relative to the flow rate of the main pipe end defined by the air conditioner manufacturer, and the pressure drop difference coefficient K increases with the decrease of the critical value of the drop ratio δV. In this embodiment, the critical value of the drop ratio δV in Table 1 is 20%, and the K obtained by fitting is 1.36. If the critical value of the drop ratio δV is adjusted to 10%, K needs to be increased; on the contrary, if the critical value of the drop ratio δV is increased, K needs to be reduced. Preferably, 1.2≤K≤1.55 is set. For the determination of the drop ratio coefficient K, the designer only needs to test a small number of test pieces in advance to obtain the basic size of each test piece satisfying the critical value of δV and substitute it into the above formula to obtain the value of K; for the design of all subsequent new type of branch pipes satisfying the drop ratio δV, the value of K obtained by calculation can be directly referenced to determine the basic size. In Formula 1, g is the acceleration of gravity.

[0070] Further, the bending angle β of the test pieces in Table 1 that meet the flow rate difference rate ΔV and the drop ratio δV requirements is further analyzed, and it is found that the maximum and minimum values of the bending angle β are related to the outer diameter D of the first branch pipe 2 near the communication zone 100 and the center distance L of the two branch pipe ends. After analyzing and fitting the data, the following formula is obtained:

[0071]

[0072]

[0073] wherein β min is the lower threshold value of the bending angle β, β max is the upper threshold value of the bending angle β, and g is the acceleration of gravity. Formulas two and three show that when designing the new diverging pipe of the present embodiment, a more accurate angle range can be determined within 40°≤β≤160° based on the determined outer diameter D of the first branch pipe 2 near the communication zone and the center distance L of the two branch pipe ends.

[0074] Similarly, the vertical height difference ΔH between the two branch pipe end faces of the test pieces in Table 1 that meet the flow rate difference rate ΔV and the drop ratio δV requirements is analyzed, and it is also found that the vertical height difference ΔH between the two branch pipe end faces is related to the ratio between the outer diameter D of the first branch pipe near the communication zone and the center distance L of the two branch pipe ends. The vertical height difference ΔH between the two branch pipe end faces satisfies the following formula:

[0075] ΔH=45+L / D Formula four

[0076] Based on Formula four, when designing the new diverging pipe of the present embodiment, a more accurate vertical height difference range can be determined within ΔH≤53mm according to the ratio between the outer diameter D of the first branch pipe near the communication zone and the center distance L of the two branch pipe ends.

[0077] Table three is an error table between the theoretical basic size (theoretical value B) calculated by Formula one and the basic size test value B(Hb) obtained by testing. The test value B(Hb) is derived from the test data Hb(B) in Table one, and the theoretical value Hb is the basic size value calculated according to Formula one. By analyzing the data in Table three, it can be found that the theoretical value B is very close to the test value B(Hb), and the error between the two is within 1mm. At the same time, Formula four is verified. The test value ΔH is very close to the theoretical value ΔH calculated by Formula four, which is the average value of the test value ΔH of multiple samples in each sub-experiment group in Table one. The data in Table two shows that the fitted Formulas one and four are very accurate.

[0078] Table 1 is based on the condition that the two angles a1 and a2 formed by the axis of the first branch pipe 2 and the extrusion section 31 near the communication zone 100 and the axis of the main pipe 1 near the communication zone are equal (β = a1 + a2). However, in the actual manufacturing process, the two angles will inevitably differ due to process deviation or installation requirements of air conditioner manufacturers. Therefore, the proportion of the two angles of each sample is changed based on the above test to observe the influence of the angle change on the uniformity of the flow distribution and the pressure drop difference, and the relevant data are recorded to form Table 2. The test data in Table 2 show that when any one of the angles enters the lower limit critical angle a min , the flow rate of the branch pipe corresponding to the angle increases sharply, which seriously deteriorates the uniformity of the flow distribution between the two branch pipes. When any one of the angles enters the upper limit critical angle a max , the transition bend angle between the branch pipe corresponding to the angle and the main pipe has a large local loss due to the large angle and small radius of curvature; similarly, the circular bend on the branch pipe also sharply increases the local loss due to the increased angle and reduced radius of curvature. The two local resistances cause the flow rate in the branch pipe at the upper limit critical angle a max to decrease sharply, which not only seriously deteriorates the uniformity of the flow distribution between the two branch pipes, but also increases the pressure drop difference of the entire pipe fitting (i.e., the energy loss is severely increased). After analyzing the angle data of all samples, it is found that the lower limit critical angle a min of the angle is close to 10°, and the upper limit critical angle a max is close to 80°.

[0079] In the actual production process, it is difficult to directly measure the angle of the pipe fitting with a three-dimensional structure, and accurate measurement requires the use of other means such as projection or dissection; moreover, and more importantly, it is difficult to analyze the change of the angle to find the rules during data analysis. Therefore, it is desirable to convert the angle to distance during data analysis. In this embodiment, the length Hb of the first branch pipe 2 when a1 = a2 is defined as the basic size B in Table 1 for the convenience of research, and the change of the basic size B with the corresponding angle is studied.

[0080] Further analysis of the pipe fitting structure shown in FIG. Figure 4 shows that the change of the angle changes the projection distance of the circular bend Re on the first branch pipe 2 to the cross section where the reference point O is located, and the change of the projection distance is also reflected in the overall length of the basic size B. As shown in FIG. Figure 7 , when the angle is a1, the corresponding basic size is B1, and when the angle decreases from a1 to a11, the basic size B1 increases to B11. Based on this change rule, it can be obtained that when a1 gradually changes from the equal angle to the lower limit critical angle a min , the height of the basic size gradually increases and reaches the maximum value B min at the lower limit critical angle a max .When the α1 gradually changes from the uniform competition angle to the upper limit critical angle α max , the basic dimension height gradually decreases and reaches the minimum B max at the upper limit critical angle α min . The basic dimension B deviation ΔB = 1 / 2(B max -B min ). In the experiment, in order to make the angle reach 80°, the test pieces that meet the requirements of ΔV and δV are selected in the sub-test groups in Table 1 to study the change range of the basic dimension when the angle changes between the upper and lower limit critical angles, and the relevant data are recorded to form Table 2.

[0081] In Table 2, β is the bending angle between the two pipes, α1 is the angle of the first branch pipe, α2 is the angle of the second branch pipe, and B(Hb) is the basic dimension after the first branch pipe angle α1 changes. Taking the sub-experimental group of D = 9.52 mm and L = 46 mm as an example, B min is the basic dimension when α1 = 80°, that is, 124.8 mm, B max is the basic dimension when α1 = 10°, that is, 177.4 mm, so ΔB = 1 / 2(177.4-124.8) = 26.3 mm; the basic dimension deviation ΔB of each sub-test group can be calculated in turn.

[0082] After analyzing all the data in Table 2, it is found that the basic dimension B deviation ΔB is positively correlated with the outer diameter D of the first branch pipe 2 near the communication zone 100 and negatively correlated with the center distance L of the two branch pipe ends. After fitting calculation of all the data, it is found that the basic dimension deviation ΔB satisfies the following relationship:

[0083]

[0084] Where D is the outer diameter of the first branch pipe near the communication zone, and L is the center distance of the two branch pipe ends.

[0085] Table 4 is the error table between the basic dimension deviation theoretical value ΔB calculated by formula five and the test value ΔB obtained from Table 2. The test value ΔB comes from Table 2, and the theoretical value ΔB is calculated by formula five. Table 4 shows that the theoretical value ΔB and the test value ΔB of all sub-test groups are very close, the error between them is very small and is within 1 mm, which indicates that formula five has good accuracy.

[0086] In designing the manifold, the selection range of the bending angle β is determined according to the formulae two and three based on the outer diameter D of the first branch pipe 2 near the communication zone and the center distance L of the two branch pipes to meet the requirement of uniform distribution. After the specific bending angle β is determined within the selection range of the bending angle β, the basic size B of one of the branch pipes is determined according to the formula one and the pressure drop difference coefficient K related to the drop ratio δV of the flow rate of the two branch pipes to the flow rate of the main pipe end which is obtained by pre-calculation to meet the requirement of the drop ratio δV. After the basic size B is obtained, the actual length range of the branch pipe is determined based on the basic size offset ΔB obtained by the formula five; and then the actual length of the other branch pipe is determined according to the vertical height difference ΔH between the end faces of the two branch pipe ends. The control of the bending angle β, the basic size B, the basic size offset ΔB and the vertical height difference ΔH between the end faces of the two branch pipe ends makes the new type of manifold provided in the embodiment well balance the pressure drop difference while meeting the requirement of uniform distribution to reduce the total energy loss of the refrigerant in the flow process.

[0087] In the embodiment, the vertical distance between the axial center line of the first branch pipe 2 and the axial center line of the main pipe 1 near the communication zone satisfies 1.3D≤L1≤3.5D, where D is the outer diameter of the first branch pipe 2 near the communication zone 100. As shown in Figure 8 , the setting can make the first heat preservation sleeve 51 sleeved from the main pipe 1 well pass through the communication zone 100 and extend to the direction of the first branch pipe 2, and then approach the second heat preservation sleeve 52 sleeved from the first branch pipe 2, and the third heat preservation sleeve 53 is sleeved from the second branch pipe 3 and approaches the communication zone 100; as shown in Figure 8 .

[0088] In the embodiment, the axial center lines of the first branch pipe 2 and the second branch pipe 3 are both parallel to the axial center line of the main pipe 1 near the communication zone. However, the present application does not make any limitation on this. In other embodiments, only the axial center line of one of the two branch pipes can be parallel to the axial center line of the main pipe near the communication zone, and the axial center line of the other branch pipe intersects with the axial center line of the main pipe near the communication zone at a small acute angle. Alternatively, the axial center lines of the two branch pipes both intersect with the axial center line of the main pipe near the communication zone at a small acute angle.

[0089] In the embodiment, the outer diameter of the main pipe 1 near the communication zone 100 is basically equal to the outer diameter D of the first branch pipe 2 near the communication zone. However, the present application does not make any limitation on this. In other embodiments, as shown in Figure 6 , the outer diameter D1 of the main pipe 1 near the communication zone 100 can also be larger than the outer diameter D of the first branch pipe 2 near the communication zone through flaring process.

[0090] In the embodiment, the main pipe 1, the first branch pipe 2 and the second branch pipe 3 are all copper pipes. However, the present application does not make any limitation on this. In other embodiments, as shown inFigure 9 As shown in the figure, the main pipe 1, the first branch pipe 2 and the extrusion section 31 of the second branch pipe are stainless steel pipes, and the extension section 32 of the second branch pipe is a copper pipe. The new branch pipe further comprises a main pipe connecting section 41 welded to the main pipe 1 and made of copper material, and a first branch pipe connecting section 42 welded to the end of the first branch pipe 2 and made of copper material.

[0091] Alternatively, in other embodiments, as shown in the figure, the main pipe 1, the first branch pipe 2 and the second branch pipe 3 are all stainless steel pipes, and the new branch pipe further comprises a main pipe connecting section 41 welded to the main pipe 1 and made of copper material, a first branch pipe connecting section 42 welded to the end of the first branch pipe 2 and made of copper material, and a second branch pipe connecting section 43 welded to the extension section 32 of the second branch pipe and made of copper material. Figure 10

[0092] Correspondingly, the embodiment also provides a refrigeration equipment comprising the new branch pipe.

[0093] Embodiment Two

[0094] The embodiment is basically the same as Embodiment One and its variations, as shown in the figure, the difference is that the main pipe 1 comprises a main pipe interface section 11 and a main pipe body 12. Figure 11

[0095] Specifically, the new branch pipe comprises a main pipe 1, a first branch pipe 2 and a second branch pipe 3. The main pipe 1 comprises a main pipe interface section 11 and a main pipe body 12 which are welded together. The first branch pipe 2 is connected to the main pipe interface section 11 and extends to one side of the main pipe interface section 11. The second branch pipe 3 comprises an extrusion section 31 and an extension section 32 welded to the extrusion section 31. The extrusion section 31 is connected to the main pipe interface section 11 and extends to the other side of the main pipe interface section 11. The extrusion section 31, the first branch pipe 2 and the main pipe interface section 11 are integrally formed and are in communication with each other through a communication area 100. The length Ha of the main pipe 1 is greater than or equal to twice the outer diameter of the first branch pipe 2 near the communication area. The length of at least one of the two branch pipes is greater than four times the outer diameter D of the first branch pipe near the communication area. The number of circular bends on the first branch pipe 2 and the second branch pipe 3 is the same.

[0096] ​​Wherein, the first branch pipe 2 and the extruding section 31 intersect with the axial line of the main pipe interface section near the communication zone 100 at the reference point O and form two angles of bending respectively, and the two angles of bending constitute the bending angle of the first branch pipe and the extruding section; the bending angle 40°≤β≤160° and the two angles of bending are both greater than or equal to 10°, and the vertical height difference ΔH between the end faces of the two branch pipes is less than or equal to 53mm; the basic dimension B of the length of one of the branch pipes is related to the bending angle, the center distance between the two branch pipe ends and the outer diameter of the first branch pipe near the communication zone, and the basic dimension offset ΔB is less than or equal to 44.5mm; the length H of the main pipe refers to the vertical distance from the end face of the main pipe body to the section where the reference point O is located, and the length of the branch pipe refers to the vertical distance from the end face of the branch pipe end to the section where the reference point is located.

[0097] In this embodiment, the basic dimension B of the length of one of the branch pipes is negatively related to the bending angle and the center distance between the two branch pipe ends respectively and is positively related to the outer diameter of the first branch pipe near the communication zone; the basic dimension B satisfies:

[0098]

[0099] Wherein, D is the outer diameter of the first branch pipe near the communication zone; β is the bending angle; L is the center distance between the two branch pipe ends; K is the pressure drop difference coefficient related to the critical value of the drop ratio δV of the flow rate of the two branch pipes to the flow rate of the main pipe end as specified by the air conditioner manufacturer; and g is the acceleration of gravity.

[0100] In the new diverging pipe provided in this embodiment, the split connection of the main pipe body 12 and the main pipe interface section 11 can make the pipe diameter of the main pipe body 12 different from that of the main pipe interface section 11, for example, the main pipe body 12 with a larger pipe diameter is selected to make the new diverging pipe better connected with the external pipeline. However, the determination of the bending angle β, the range of the two angles of bending, the vertical height difference ΔH between the end faces of the two branch pipes, the basic dimension B and the basic dimension offset ΔB is the same as that in Embodiment One, which will not be repeated here.

[0101] Embodiment Three

[0102] This embodiment is basically the same as Embodiment One and its variations, as shown in Figure 12 The difference is that the included angle between the axial line of the end of the second branch pipe extension section 32 and the axial line of the main pipe 1 near the communication zone 100 is 80°≤θ≤100°; this setting makes the direction of the refrigerant output by the second branch pipe extension section 32 close to perpendicular to the direction of the refrigerant input by the main pipe end to realize the distribution of refrigerants in different directions.

[0103] Specifically, the new manifold includes a main pipe 1, a first branch pipe 2 and a second branch pipe 3, the second branch pipe 3 includes an extrusion section 31 and an extension section 32 welded to the extrusion section 31, the extrusion section 31 and the first branch pipe 2 extend to both sides of the main pipe respectively, the extrusion section 31, the main pipe 1 and the first branch pipe 2 are integrally formed and are in communication with each other through a communication area 100; the included angle between the axial center line of the end of the extension section 32 and the axial center line of the main pipe 1 at the communication area is 80°≤θ≤100°. The length of the main pipe 1 is greater than or equal to twice the outer diameter D of the first branch pipe 2 at the communication area, and the length of the first branch pipe 2 is greater than four times the outer diameter D of the first branch pipe at the communication area.

[0104] Wherein, the number of round bends Re on the first branch pipe 2 and the second branch pipe 3 is the same, and the round bends Re on the second branch pipe 3 are located on the extension section 32, the axial center lines of the first branch pipe 2 and the extrusion section 31 near the communication area respectively intersect with the axial center line of the main pipe 1 near the communication area at a reference point O and respectively form two angles, and the two angles constitute the bending angle β of the first branch pipe and the extrusion section; the bending angle is 40°≤β≤160°, and both angles are greater than or equal to 10°. The basic size B of the length of the first branch pipe 2 is negatively related to the bending angle and the transverse distance L' between the axial center line of the first branch pipe 2 and the extension end M of the round bend Re on the extension section 32, and is positively related to the outer diameter D of the first branch pipe 2 near the communication area, and the basic size offset ΔB≤44.5mm; the length Ha of the main pipe refers to the vertical distance from the end face of the main pipe 1 to the section where the reference point O is located, and the length Hb of the first branch pipe 2 refers to the vertical distance from the end face of the first branch pipe 2 to the section where the reference point O is located. The extension end M of the round bend Re on the extension section 32 refers to the end far away from the extrusion section 31.

[0105] The determination of the bending angle β, the range of the two angles, the vertical height difference ΔH between the end faces of the two branch pipes, the basic size B and the basic size offset ΔB is the same as that of Embodiment One, and the present application will not be repeated here.

[0106] In summary, the new manifold provided by the application introduces the number of round bends, the angle of division and the offset of the length of the branch pipe relative to the basic size of the length to control the difference in local resistance loss between the two branch pipes based on the bending angle between the two branch pipes; at the same time, the vertical height difference between the end faces is controlled to further reduce the influence of the difference in the flow resistance between the two branch pipes, thereby realizing the control of the uniformity of the two branch pipes. As for the pressure drop between the input and the output, the length of the branch pipe is accurately controlled based on the outer diameter of the first branch pipe near the communication area, the bending angle and the center distance of the two branch pipe ends, so that the two branch pipes meet the installation requirements while the overall resistance loss of the product meets the requirements of the system pressure drop. The accurate setting of multiple parameters between the two branch pipes in the new manifold provided by the application not only makes the product have excellent flow uniformity, but also greatly reduces the pressure drop between the input and the output, so that the multi-connected air conditioning (heat pump) system has a higher energy efficiency ratio.

[0107] Although the present application has been disclosed by the preferred embodiments as above, it is not intended to limit the present application, and any person skilled in the art can make some changes and modifications without departing from the spirit and scope of the present application, so the protection scope of the present application shall be subject to the scope claimed by the claims.

[0108] In the following table:

[0109] D is the outer diameter of the first branch pipe near the communication area, and the unit is mm;

[0110] L is the center distance of the two branch pipe ends, and the unit is mm;

[0111] β is the bending angle between the two branch pipes, and the unit is °;

[0112] Va is the refrigerant flow rate of the main pipe end, and the unit is m / s;

[0113] Vb is the refrigerant flow rate of the first branch pipe, and the unit is m / s;

[0114] Hb(B) is the length of the first branch pipe, and the unit is mm;

[0115] Vc is the refrigerant flow rate of the second branch pipe, and the unit is m / s;

[0116] Hc is the length of the second branch pipe, and the unit is mm;

[0117] △V is the flow rate difference rate of the refrigerant between the two branch pipes;

[0118] ΔH is the vertical height difference between the end faces of the two branch pipe ends, and the unit is mm;

[0119] δV is the flow rate drop ratio of the two branch pipes relative to the flow rate of the main pipe end;

[0120] AB is the basic dimensional offset, in mm;

[0121] The units of the test value B (Hb), the theoretical value B, the test value AH, the theoretical value AH, the test value AB, and the theoretical value AB are all mm.

[0122] Table I

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139] Table II

[0140]

[0141]

[0142]

[0143]

[0144] Table III

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155]

[0156]

[0157]

[0158]

[0159]

[0160]

[0161]

[0162] Table IV

[0163]

[0164]

[0165]

[0166]

[0167] Table V

[0168]

Claims

1. A novel branch pipe, characterized in that, include: The system comprises a main pipe, a first branch pipe, and a second branch pipe. The second branch pipe includes an extruded section and an extension section welded to the extruded section. The extruded section and the first branch pipe extend to both sides of the main pipe. The extruded section, the main pipe, and the first branch pipe are integrally formed and interconnected through a connecting area. The length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the connecting area. At least one of the two branch pipes has a length greater than four times the outer diameter of the first branch pipe near the connecting area. The number of round bends on the first branch pipe and the second branch pipe is the same. The centerlines of the first branch pipe and the extrusion section near the connecting area intersect the centerline of the main pipe near the connecting area at a reference point, forming two bisector angles. These two bisector angles constitute the bending angles of the first branch pipe and the extrusion section. The bending angles are 40°≤β≤160°, and both bisector angles are greater than or equal to 10°. The vertical height difference ΔH between the end faces of the two branch pipes is ≤53mm. The basic dimension B of the length of one branch pipe is related to the bending angle, the center distance between the ends of the two branch pipes, and the outer diameter of the first branch pipe near the connecting area, and the basic dimension offset is... △B≤44.5mm; The length of the main pipe refers to the vertical distance from the end face of the main pipe to the cross section where the reference point is located, and the length of the branch pipe refers to the vertical distance from the end face of the branch pipe to the cross section where the reference point is located. The basic dimension offset ΔB is positively correlated with the outer diameter of the first branch pipe near the connection zone and negatively correlated with the center distance between the ends of the two branch pipes. The basic dimension offset ΔB satisfies the following relationship: Where D is the outer diameter of the first branch pipe near the connecting area, in mm; L is the center distance between the ends of the two branch pipes, in mm.

2. The novel branch pipe according to claim 1, characterized in that, The basic dimension B of the length of one branch pipe is negatively correlated with the bending angle and the center distance between the ends of the two branch pipes, and positively correlated with the outer diameter of the first branch pipe near the connection zone.

3. The novel branch pipe according to claim 1, characterized in that, The basic dimension B of one branch pipe, the outer diameter D of the first branch pipe near the connection zone, the bending angle β, and the center distance L between the ends of the two branch pipes satisfy the following relationship: Wherein, K is the pressure drop coefficient related to the critical value of the decrease ratio δV of the flow velocity of the two branch pipes relative to the flow velocity of the main pipe as specified by the air conditioner manufacturer; g is the acceleration due to gravity; the unit of the basic dimension B is mm; the unit of the outer diameter D of the first branch pipe near the connection area is mm; and the unit of the center distance L between the ends of the two branch pipes is mm.

4. The novel branch pipe according to claim 3, characterized in that, The pressure drop coefficient K satisfies: 1.2≤K≤1.

55.

5. The novel branch pipe according to claim 1, characterized in that, The maximum and minimum values ​​of the bending angle β formed between the first branch pipe and the extrusion section are both related to the outer diameter D of the first branch pipe near the connection zone and the center distance L between the ends of the two branch pipes, respectively; where: Where, β min The lower threshold value of the bending angle β, β max The upper limit threshold of the bending angle β, g is the acceleration due to gravity, and the units of D and L are mm.

6. The novel branch pipe according to claim 1, characterized in that, The vertical height difference ΔH between the end faces of the two branch pipes is related to the ratio between the outer diameter D of the first branch pipe near the connection zone and the center distance L between the ends of the two branch pipes. The vertical height difference ΔH between the end faces of the two branch pipes satisfies: ΔH = 45 + L / D; The units for △H, D, and L are mm.

7. The novel branch pipe according to claim 1, characterized in that, The number of round bends on the first and second branch pipes is one, and at least one of the centerlines at the ends of the two branch pipes is parallel to the centerline of the main pipe near the connecting area.

8. The novel branch pipe according to claim 1, characterized in that, The main pipe, the first branch pipe, and the second branch pipe are all copper pipes; Alternatively, the main pipe, the first branch pipe, and the extruded section of the second branch pipe are all stainless steel pipes, and the extension section is a copper pipe; the new type of branch pipe also includes a main pipe connecting section welded to the main pipe and made of copper material and a first branch pipe connecting section welded to the end of the first branch pipe and made of copper material. Alternatively, the main pipe, the first branch pipe, and the second branch pipe are all stainless steel pipes. The novel branch pipe also includes a main pipe connecting section welded to the main pipe and made of copper, a first branch pipe connecting section welded to the first branch pipe and made of copper, and a second branch pipe connecting section welded to the extension of the second branch pipe and made of copper.

9. The novel branch pipe according to claim 1, characterized in that, The vertical distance between the centerline of the end of the first branch pipe and the centerline of the main pipe near the connecting area is 1.3D≤L1≤4D, where D is the outer diameter of the first branch pipe near the connecting area; and L1, D and L are in mm.

10. A novel branch pipe, characterized in that, include: The main body includes the welded main body interface segment and the main body itself; The first branch pipe is connected to the main pipe interface section and extends to one side of the main pipe interface section; The second branch pipe includes an extruded section and an extension section welded to the extruded section. The extruded section is connected to the main pipe interface section and extends to the other side of the main pipe interface section. The extruded section, the first branch pipe, and the main pipe interface section are integrally formed and interconnected through a connecting area. The length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the connecting area. At least one of the two branch pipes has a length greater than four times the outer diameter of the first branch pipe near the connecting area. The number of bends on the first and second branch pipes is the same. The centerlines of the first branch pipe and the extrusion section near the connecting area intersect the centerline of the main pipe interface section near the connecting area at a reference point and form two bisectors, which constitute the bending angle of the first branch pipe and the extrusion section. The bending angle is 40°≤β≤160° and both bisectors are greater than or equal to 10°. The vertical height difference ΔH between the end faces of the two branch pipes is ≤53mm. The basic dimension B of the length of one branch pipe is related to the bending angle, the center distance between the ends of the two branch pipes, and the outer diameter of the first branch pipe near the connecting area, and the basic dimension offset ΔB≤44.5mm. The length of the main pipe refers to the vertical distance from the end face of the main pipe body to the cross section where the reference point is located. The length of the branch pipe refers to the vertical distance from the end face of the branch pipe to the cross section where the reference point is located. The basic dimension offset ΔB is positively correlated with the outer diameter of the first branch pipe near the connection zone and negatively correlated with the center distance between the ends of the two branch pipes. The basic dimension offset ΔB satisfies the following relationship: Where D is the outer diameter of the first branch pipe near the connecting area, in mm; L is the center distance between the ends of the two branch pipes, in mm.

11. The novel branch pipe according to claim 10, characterized in that, The basic dimension B of the length of one branch pipe is negatively correlated with the bending angle and the center distance between the ends of the two branch pipes, and positively correlated with the outer diameter of the first branch pipe near the connection zone; the basic dimension B satisfies: Where D is the outer diameter of the first branch pipe near the connection zone, in mm; β is the bending angle; L is the center distance between the ends of the two branch pipes, in mm; K is the pressure drop coefficient related to the critical value of the decrease ratio δV of the flow velocity of the two branch pipes relative to the flow velocity of the main pipe as specified by the air conditioner manufacturer; and g is the acceleration due to gravity.

12. A novel branch pipe, characterized in that, include: The system comprises a main pipe, a first branch pipe, and a second branch pipe. The second branch pipe includes an extruded section and an extension section welded to the extruded section. The extruded section and the first branch pipe extend to both sides of the main pipe. The extruded section, the main pipe, and the first branch pipe are integrally formed and interconnected through a connecting area. The angle between the centerline of the end of the extension section and the centerline of the main pipe near the connecting area is 80°≤θ≤100°. The length of the main pipe is greater than or equal to twice the outer diameter of the first branch pipe near the connecting area, and the length of the first branch pipe is greater than four times the outer diameter of the first branch pipe near the connecting area. The first and second branch pipes have the same number of bends, with the bends on the second branch pipe located on the extension section. The centerlines of the first branch pipe and the extrusion section near the connecting area intersect the centerline of the main pipe near the connecting area at a reference point, forming two bisectors. These two bisectors constitute the bending angle of the first branch pipe and the extrusion section. The bending angle is 40°≤β≤160°, and both bisectors are greater than or equal to 10°. The basic dimension B of the first branch pipe length is negatively correlated with the bending angle and the lateral distance between the centerline of the first branch pipe and the extension end of the bend on the extension section, and positively correlated with the outer diameter of the first branch pipe near the connecting area. The basic dimension offset △B≤44.5mm. The length of the main pipe refers to the vertical distance from the end face of the main pipe to the cross section where the reference point is located, and the length of the first branch pipe refers to the vertical distance from the end face of the first branch pipe to the cross section where the reference point is located. The basic dimension offset ΔB is positively correlated with the outer diameter of the first branch pipe near the connection zone and negatively correlated with the center distance between the ends of the two branch pipes. The basic dimension offset ΔB satisfies the following relationship: Where D is the outer diameter of the first branch pipe near the connecting area, in mm; L is the center distance between the ends of the two branch pipes, in mm.

13. A refrigeration device, characterized in that, Including the novel branch pipe as described in any one of claims 1 to 12.

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