Pipe-in-pipe joint

Abstract

The technical scheme belongs to the technical field of pipeline connection, and particularly relates to a pipe-in-pipe joint, which is used for connecting a pipe-in-pipe with a pipe-in-pipe outer pipe and a pipe-in-pipe inner pipe, and comprises a joint outer pipe which is at least provided with an outer pipe mounting part and is used for connecting the pipe-in-pipe outer pipe; the joint inner pipe is arranged in the joint outer pipe through a connecting part, a first channel is formed between the joint inner pipe and the joint outer pipe, and the joint inner pipe is provided with an inner pipe mounting part corresponding to the outer pipe mounting part and a second channel formed in the joint inner pipe; the connector is made of a high-temperature-resistant material, is mounted on the inner pipe mounting part and is used for connecting an inner pipe of the pipe-in-pipe; the connector is made of high-temperature-resistant materials, connection between the connector inner pipe and the pipe-in-pipe inner pipe is achieved through the connector, deformation of the connector inner pipe due to long-time heating in the hot melting operation process is prevented, and therefore it is guaranteed that connection between the connector inner pipe and the pipe-in-pipe inner pipe is stable and good in sealing performance; the stability of the whole pipeline system is improved.

Description

TECHNICAL FIELD

[0001] The technical scheme relates to the technical field of pipeline connection, and particularly relates to a pipe-in-pipe joint. BACKGROUND

[0002] At present, the pipe-in-pipe pipeline comprises a pipe-in-pipe and a pipe-in-pipe joint, the pipe-in-pipe is composed of a pipe-in-pipe inner pipe and a pipe-in-pipe outer pipe, and the pipe-in-pipe joint is composed of a joint outer pipe and a joint inner pipe.

[0003] For example, a pipe-in-pipe joint for controlling a single channel is disclosed in Chinese Patent CN201922498058.4, which comprises a joint outer pipe and a joint inner pipe, the end of the joint outer pipe is connected to the end of the pipe-in-pipe outer pipe, and the end of the joint inner pipe is connected to the end of the pipe-in-pipe inner pipe, so as to realize the communication of the inner channel and the outer channel of the two, respectively.

[0004] However, the existing pipe-in-pipe connection still has some deficiencies.

[0005] When performing hot melt connection of the pipe-in-pipe pipe fitting (including a pipeline, a joint and a device mounting end), due to the operation errors of workers, such as lack of experience, inattention or failure to strictly follow the operation procedures, the hot melt time is too long, and such excessive heating will cause the joint inner pipe plastic to be exposed to high temperature for a long time, which will cause material deformation, and then affect the dimensional accuracy, installation adaptability and sealing performance of the pipeline. SUMMARY

[0006] The technical scheme aims to provide a pipe-in-pipe joint, which is made of high-temperature-resistant material through a connecting head, so as to improve the problem of deformation of the joint inner pipe caused by long-time high-temperature hot melt.

[0007] The technical scheme is achieved in the following manner:

[0008] A pipe-in-pipe joint is used for connecting a pipe-in-pipe having a pipe-in-pipe outer pipe and a pipe-in-pipe inner pipe, and comprises:

[0009] a joint outer pipe having at least one outer pipe mounting portion for connecting the pipe-in-pipe outer pipe;

[0010] a joint inner pipe arranged in the joint outer pipe through a connecting portion and forming a first channel with the joint outer pipe, and having an inner pipe mounting portion corresponding to the outer pipe mounting portion and a second channel formed in the joint inner pipe; and

[0011] a connecting head made of high-temperature-resistant material and mounted on the inner pipe mounting portion for connecting the pipe-in-pipe inner pipe.

[0012] Preferably, the connecting head is made of metal or high-temperature-resistant plastic.

[0013] Preferably, the high-temperature-resistant plastic is PPS or PEEK or PPA plastic or PSF or PSU.

[0014] Preferably, the connector comprises:

[0015] a fitting portion mounted on the inner wall of the inner tube mounting portion; and

[0016] a plug-in portion formed on the fitting portion for connecting a pipe-in-pipe inner tube;

[0017] wherein the plug-in portion has a positioning segment and a fastening segment, and the diameter of the positioning segment is smaller than that of the fastening segment.

[0018] Preferably, the plug-in portion has a slope on the outer side wall, the positioning segment and the fastening segment are connected through the slope, and the slope makes the diameter of the plug-in portion increase stepwise in the direction close to the fitting portion.

[0019] Preferably, the outer side wall of the fitting portion is provided with an anti-disengagement portion, which is a barb or a protrusion or a bump or a protruding strip.

[0020] Preferably, the connector is a metal sleeve sleeved outside the end of the inner tube mounting portion for preventing high-temperature deformation of the inner tube mounting portion.

[0021] Preferably, a sealing ring is sleeved on the inner tube mounting portion or the connector.

[0022] When the inner tube mounting portion or the connector is connected with the pipe-in-pipe inner tube, the sealing ring abuts against the end of the pipe-in-pipe inner tube.

[0023] Preferably, the connector and the inner tube mounting portion are press-fitted through interference fit or integrally injection molded.

[0024] Preferably, the connector outer tube, the connector inner tube and the connecting portion are injection molded by PP-R pipe or PE material or PVC material or PS material.

[0025] The technical scheme has the following prominent and beneficial technical effects compared with the prior art:

[0026] 1. The connector designed in the technical scheme is made of high-temperature-resistant material, and the connection between the connector inner tube and the pipe-in-pipe inner tube is realized through the connector, which prevents the connector inner tube from deforming due to long-time heating during hot melting operation, thereby ensuring that the connection between the connector inner tube and the pipe-in-pipe inner tube is stable and has good sealing performance, and improving the stability of the entire pipeline system.

[0027] 2、The technical scheme designs the assembly part of the connecting head to be connected with the inner pipe mounting part, the assembly part improves the connection stability between the assembly part and the inner pipe mounting part through the anti-dropping part, avoids the connecting head from loosening or falling off from the inner pipe of the joint, and ensures the stable connection.

[0028] 3、The technical scheme designs the plug-in part to include a positioning section, a slope and a fastening section, the diameter of the positioning section is smaller than that of the fastening section, the positioning section is used for facilitating the pipe-in-pipe inner pipe sleeve to be sleeved on the positioning section, and the slope is used for the connection transition between the positioning section and the fastening section, so that the fastening section can effectively abut against the inner wall of the pipe-in-pipe inner pipe and realize the tight connection, and the convenience of installation and the stability of the connection are improved.

[0029] 4、The technical scheme tightly fits the sealing ring on the connection between the pipe-in-pipe inner pipe and the inner pipe mounting part, avoids the leakage of liquid from the connection, and thus ensures the sealing property of the whole inner pipe system and the efficient operation of the inner pipe system. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a structure schematic view of the pipe-in-pipe joint of the technical scheme.

[0031] Figure 2 It is a structure schematic view of the second pipe-in-pipe joint of the technical scheme.

[0032] Figure 3 It is Figure 2 a sectional view at A-A.

[0033] Figure 4 It is a structure schematic view of the connecting head of the technical scheme.

[0034] Figure 5 It is a structure schematic view of the second pipe-in-pipe joint and the pipe-in-pipe connection of the technical scheme.

[0035] Figure 6 It is a structure schematic view of the third pipe-in-pipe joint of the technical scheme.

[0036] Figure 7 It is a structure schematic view of the fourth pipe-in-pipe joint of the technical scheme.

[0037] Figure 8 It is a structure schematic view of the fifth pipe-in-pipe joint of the technical scheme.

[0038] Reference signs: 1, joint outer pipe; 11, outer pipe mounting part; 12, first channel; 13, connecting end; 14, connecting piece; 15, threaded part;

[0039] 2, joint inner pipe; 21, inner pipe mounting part; 22, second channel; 23, connecting part;

[0040] 3, connector; 31, assembly part; 32, anti-dropping part; 33, plug-in part; 34, positioning section; 35, slope; 36, fastening section; 37, third passage; 38, limiting platform;

[0041] 4, metal sleeve; 5, sealing ring; 6, outer pipe of pipe-in-pipe; 7, inner pipe of pipe-in-pipe. DETAILED DESCRIPTION

[0042] The specific embodiments of the technical solution will be further described in detail below with reference to the accompanying drawings.

[0043] Example 1

[0044] In combination with Figure 1 , Figure 2 , Figure 3 and Figure 5 , a pipe-in-pipe connector is used to connect a pipe-in-pipe, which includes an outer pipe 6 of pipe-in-pipe, an inner pipe 7 of pipe-in-pipe, and a connecting strip connecting the two.

[0045] The pipe-in-pipe connector includes:

[0046] an outer pipe 1 of connector, which has at least one outer pipe mounting part 11 for connecting the outer pipe 6 of pipe-in-pipe;

[0047] an inner pipe 2 of connector, which is arranged in the outer pipe 1 of connector through a connecting part 23 and forms a first passage 12 with the outer pipe 1 of connector, and the inner pipe 2 of connector has an inner pipe mounting part 21 corresponding to the outer pipe mounting part 11 and a second passage 22 formed in the inner pipe 2 of connector; and

[0048] a connector 3 made of high-temperature-resistant material and mounted on the inner pipe mounting part 21, which is used to connect the inner pipe 7 of pipe-in-pipe, and the connector 3 has a third passage 37 communicating with the second passage 22 inside;

[0049] The connector 3 is made of high-temperature-resistant material, which ensures that when the pipe-in-pipe connector is connected to the pipe-in-pipe through hot melting, even if the duration of the hot melting process is long, the inner pipe 2 of connector can be effectively prevented from deforming due to high temperature for a long time, thereby ensuring the stability and sealing performance of the connected pipeline.

[0050] When the outer pipe 1 of connector has at least one outer pipe mounting part 11, the inner pipe 2 of connector also has at least one inner pipe mounting part 21, and the connector 3 is mounted on the at least one inner pipe mounting part 21, and the end of the outer pipe 1 of connector without the outer pipe mounting part 11 can be directly mounted on other pipe-in-pipe equipment;

[0051] When the outer pipe 1 of connector has two or more outer pipe mounting parts 11, the inner pipe 2 of connector has at least one inner pipe mounting part 21, and the connector 3 is mounted on the inner pipe mounting part 21.

[0052] The connecting head 3 is made of metal or high-temperature-resistant plastic, such as stainless steel, copper, titanium alloy, PPS (polyphenylene sulfide), PEEK (polyether ether ketone), high-temperature-resistant nylon (PPA plastic), or polysulfone (PSF or PSU).

[0053] The high-temperature-resistant plastic is preferably PPS (polyphenylene sulfide), or alternatively PEEK (polyether ether ketone), high-temperature-resistant nylon (PPA plastic), or polysulfone (PSF or PSU).

[0054] As shown in Figure 4 The connecting head 3 comprises:

[0055] a fitting portion 31 mounted on the inner wall of the inner pipe mounting portion 21; and

[0056] a plug-in portion 33 formed on the fitting portion 31 for connecting the pipe-in-pipe inner pipe 7;

[0057] The plug-in portion 33 has a positioning section 34 and a fastening section 36, and the diameter of the positioning section 34 is smaller than that of the fastening section 36.

[0058] During the insertion of the plug-in portion 33 into the pipe-in-pipe inner pipe 7, the smaller diameter of the positioning section 34 allows easier insertion into the pipe-in-pipe inner pipe 7, thereby facilitating the positioning of the worker, while the larger diameter of the fastening section 36 allows abutment with the inner wall of the pipe-in-pipe inner pipe 7, thereby firmly securing the pipe-in-pipe inner pipe 7.

[0059] The outer side wall of the plug-in portion 33 has a slope 35 for the diameter of the plug-in portion 33 to increase in steps in the direction close to the fitting portion 31, i.e., the diameter of the side of the plug-in portion 33 close to the fitting portion 31 is larger than that of the side of the plug-in portion 33 away from the fitting portion 31, and the size of the plug-in portion 33 increases in steps, which can effectively connect the plug-in portion 33 with the pipe-in-pipe inner pipe 7.

[0060] The positioning section 34 and the fastening section 36 are connected and transitioned through the slope 35, and the slope 35 plays a guiding role, which can guide the end of the pipe-in-pipe inner pipe 7 from the positioning section 34 to the fastening section 36.

[0061] The diameter of the fitting portion 31 is larger than that of the plug-in portion 33, and a limiting table 38 is formed on the fitting portion 31, which abuts against the end of the pipe-in-pipe inner pipe 7 when the plug-in portion 33 is connected with the pipe-in-pipe inner pipe 7, thereby limiting the movement of the pipe-in-pipe inner pipe 7 on the connecting head 3, and when the limiting table 38 abuts against the end of the pipe-in-pipe inner pipe 7, i.e., the pipe-in-pipe inner pipe 7 is installed in place with the connecting head 3.

[0062] The outer side wall of the fitting portion 31 is provided with an anti-disengagement portion 32, which can be firmly fixed on the inner pipe 2.

[0063] The anti-disengagement part 32 is a barb or a protrusion or a bump or a protrusion strip. In the design scheme, the anti-disengagement part 32 is a barb, which is a protruding ring arranged at the side end of the assembly part 31. The side of the protruding ring close to the plug-in part 33 is provided with an anti-disengagement surface, which is arranged perpendicularly to the axis of the connector 3 or is arranged obliquely towards the plug-in part 33. The side of the protruding ring away from the plug-in part 33 is provided with a guide surface, which is arranged obliquely towards the plug-in part 33, and is used to assist the assembly part 31 to be inserted into the inner pipe mounting part 21.

[0064] The connector 3 and the inner pipe mounting part 21 are connected by interference fit or integrally formed by injection molding.

[0065] The connector outer pipe 1, the connector inner pipe 2 and the connecting part 23 are preferably PP-R plastic injection molded, that is, PP-R pipe, or can be injection molded by PE material (polyethylene) or PVC material (polyvinyl chloride) or PS material (polystyrene).

[0066] Embodiment two:

[0067] The design scheme of the embodiment is basically the same as that of embodiment one, and the difference lies in that:

[0068] As shown in Figure 6 , the end of the connector outer pipe 1 without the outer pipe mounting part 11 is a connecting end 13, and the connecting end 13 is internally provided with a threaded part 15. The connecting end 13 can be directly connected with other pipe-in-pipe equipment, and the pipe-in-pipe equipment can be a control valve, a faucet, a shower, a radiator or a circulating pump, etc.

[0069] Specifically, the connecting end 13 of the connector outer pipe 1 is provided with a connecting piece 14, and the connecting piece 14 is internally provided with a threaded part 15. The threaded part 15 is threadedly connected with other pipe-in-pipe equipment.

[0070] Embodiment three:

[0071] The design scheme of the embodiment is basically the same as that of embodiment one, and the difference lies in that:

[0072] As shown in Figure 7 , the connector 3 is a metal sleeve 4 which is sleeved outside the end of the inner pipe mounting part 21, and is used to prevent the inner pipe mounting part 21 from being deformed at high temperature.

[0073] The end of the inner pipe mounting part 21 forms a fixing part which can be used for the pipe-in-pipe inner pipe 7 to be sleeved. The outer side wall of the end of the inner pipe mounting part 21 is concave to form a mounting groove. The connector 3 (i.e. the metal sleeve 4) is directly sleeved at the end of the inner pipe mounting part 21 and is placed in the mounting groove.

[0074] The metal sleeve 4 and the inner pipe mounting part 21 are connected by secondary injection molding or are connected by interference fit.

[0075] Further solutions, such as Figure 8 The length of the metal sleeve 4 is longer, so that the metal sleeve 4 can wrap more of the outer side wall of the inner tube mounting portion 21 (i.e. the outer side wall of the fixed portion), at which time the metal sleeve 4 can be connected with the inner wall of the pipe-in-pipe inner tube 7, and the outer side wall of the inner tube mounting portion 21 (i.e. the outer side wall of the fixed portion) is no longer connected with the inner wall of the pipe-in-pipe inner tube 7.

[0076] Embodiment four:

[0077] The design scheme of the present embodiment is basically the same as that of embodiment three, and the difference lies in that:

[0078] As shown in Figure 7 The sealing ring 5 is sleeved on the inner tube mounting portion 21, and the sealing ring 5 is a rubber gasket or a silica gel ring or sealing glue.

[0079] When the inner tube mounting portion 21 is connected with the pipe-in-pipe inner tube 7, the sealing ring 5 abuts against the end of the pipe-in-pipe inner tube 7, so that the sealing ring 5 seals the connection gap between the inner tube mounting portion 21 and the pipe-in-pipe inner tube 7, avoiding the problem of water leakage.

[0080] Embodiment five:

[0081] The design scheme of the present embodiment is basically the same as that of embodiment one, and the difference lies in that:

[0082] The sealing ring 5 is sleeved on the connecting head 3, and the sealing ring 5 is located at the bottom of the plug-in portion 33, and the sealing ring 5 is a rubber gasket or a silica gel ring or sealing glue.

[0083] When the connecting head 3 is connected with the pipe-in-pipe inner tube 7, the end of the pipe-in-pipe inner tube 7 abuts against the sealing ring 5 and abuts the sealing ring 5 on the limiting table 38, and the sealing ring 5 seals the connection gap between the connecting head 3 and the pipe-in-pipe inner tube 7, avoiding the problem of water leakage.

[0084] The basic principles and main features of the present technical solution and the advantages of the present technical solution are shown and described above. It should be understood by those skilled in the art that the present technical solution is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present technical solution. Without departing from the spirit and scope of the present technical solution, various changes and improvements can be made to the present technical solution, and these changes and improvements all fall within the scope of the claimed present technical solution. The scope of protection of the present technical solution is defined by the appended claims and their equivalents.

[0085] It is to be understood that the structures, proportions, sizes, etc. shown in the drawings of the present disclosure are merely intended to facilitate the understanding of the present disclosure and are not intended to limit the conditions under which the present technical solution can be implemented. Therefore, any modification of the structure, change of the proportion relationship or adjustment of the size, which does not affect the effects and purposes that can be achieved by the present technical solution, shall still fall within the scope of the technical content disclosed by the present technical solution.

[0086] In addition, the descriptions involving "first", "second", etc. in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but must be based on the realization of ordinary skilled in the art. When the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of such technical solutions does not exist and is not within the protection scope required by the present application.

Claims

1. A pipe-in-pipe joint for connecting a pipe-in-pipe having a pipe-in-pipe outer pipe (6) and a pipe-in-pipe inner pipe (7), characterized in that The utility model relates to a pipe-in-pipe joint, comprising: a joint outer pipe (1) having at least one outer pipe mounting portion (11) for connecting a pipe-in-pipe outer pipe (6); a joint inner pipe (2) arranged in the joint outer pipe (1) through a connecting portion (23) and forming a first channel (12) with the joint outer pipe (1), and the joint inner pipe (2) having an inner pipe mounting portion (21) corresponding to the outer pipe mounting portion (11) and a second channel (22) formed in the joint inner pipe (2); and a connecting head (3) made of high-temperature-resistant material and mounted on the inner pipe mounting portion (21) for connecting a pipe-in-pipe inner pipe (7).

2. The pipe-in-pipe joint according to claim 1, wherein: the connecting head (3) is made of metal or high-temperature-resistant plastic.

3. The pipe-in-pipe joint according to claim 2, wherein: the high-temperature-resistant plastic is PPS or PEEK or PPA plastic or PSF or PSU.

4. The pipe-in-pipe joint according to any one of claims 1-3, wherein: the connecting head (3) comprises: a fitting portion (31) mounted on the inner wall of the inner pipe mounting portion (21); and a plug-in portion (33) formed on the fitting portion (31) for connecting the pipe-in-pipe inner pipe (7); wherein the plug-in portion (33) has a positioning segment (34) and a fastening segment (36), and the diameter of the positioning segment (34) is smaller than that of the fastening segment (36).

5. The pipe-in-pipe joint according to claim 4, wherein: the plug-in portion (33) has a slope (35) on its outer side wall, the positioning segment (34) and the fastening segment (36) are connected through the slope (35), and the slope (35) makes the diameter of the plug-in portion (33) increase step by step in the direction close to the fitting portion (31).

6. The pipe-in-pipe joint according to claim 4, wherein: the outer side wall of the fitting portion (31) is provided with an anti-disengagement portion (32), and the anti-disengagement portion (32) is a barb, a protrusion, a bump or a protruding strip.

7. The pipe-in-pipe joint according to claim 2, wherein: the connecting head (3) is a metal sleeve (4) sleeved on the outer side of the end portion of the inner pipe mounting portion (21) for preventing the inner pipe mounting portion (21) from deforming at high temperature.

8. The pipe-in-pipe joint according to claim 1 or 2 or 3 or 7, wherein: a sealing ring (5) is sleeved on the inner pipe mounting portion (21) or the connecting head (3); when the inner pipe mounting portion (21) or the connecting head (3) is connected with the pipe-in-pipe inner pipe (7), the sealing ring (5) abuts against the end portion of the pipe-in-pipe inner pipe (7).

9. The pipe-in-pipe joint according to claim 1 or 2 or 3 or 7, wherein: the connecting head (3) and the inner pipe mounting portion (21) are press-fitted through interference fit or integrally injection molded.

10. The pipe-in-pipe joint according to claim 1, wherein: The joint outer tube (1), the joint inner tube (2) and the connecting part (23) are injection molded from PP-R pipe or PE material or PVC material or PS material.

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