Building heating and ventilation pipeline closed connecting device
Through the combined structure of the inner insert and the outer joint, combined with the design of bolt pressurization, flexible interlayer and reinforcement block, the problem of easy leakage in HVAC pipe connection is solved, and the connection effect of efficient sealing and low energy consumption is achieved.
Patent Information
- Application Number
- CN202510821987.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-19
- Publication Date
- 2025-07-29
AI Technical Summary
The existing HVAC connection technology in the building is susceptible to the aging of elastic gaskets, chemical media erosion and thermal cycling vibration, resulting in a degradation of sealing performance, and high installation quality dependence, which makes it prone to leakage.
The combined structure of the inner insert and the outer joint is adopted, and the inner insert and the pipe are interspersed. The outer joint includes a locking part and a screw joint. It uses bolt pressing, flexible interlayer force conversion and reinforcement block filling gaps. Combined with thread rotation junction axial compression, an adaptive radial compression seal is formed, combined with the through hole and drainage groove design, and reduce heat loss.
It is achieved that it is not easy to leak under thermal cycling and vibration conditions, reduces energy loss, improves sealing and installation reliability, and reduces maintenance difficulty.
Smart Images
Figure CN120384998A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of pipeline connection, and in particular to a closed connection device for building HVAC pipelines. Background Art
[0002] In modern buildings, the HVAC system is the core facility to ensure the comfort of the indoor environment and the requirements of specific process environments. The HVAC pipeline system is the "blood circulation system" of the HVAC system. These pipelines are usually made of metal or non-metal and need to be connected to form a complex pipe network.
[0003] Pipeline connection points are numerous and extremely critical in the entire pipe network system. Pipeline connection points need to consider sealing to prevent medium leakage, avoid energy loss, system efficiency decline, condensation corrosion of building structures, environmental pollution or impact on indoor air quality.
[0004] Currently, the mainstream connection technology for building HVAC pipelines is flange connection. Through two flange plates with annular flanges, they are fixed at the pipe ends by welding or threading, and a gasket is sandwiched in the middle for sealing. When in use, align the flange plates at both pipe ends, place a gasket in the middle, insert bolts and tighten the nuts evenly and symmetrically. Use the bolt tension to compress the flange plates and squeeze the gasket to deform and fill the tiny gaps between the flange sealing surfaces, thereby achieving sealing.
[0005] However, flanges rely relatively heavily on elastic gaskets. Elastic gaskets such as rubber are prone to aging, compression permanent deformation, failure due to chemical medium erosion or high temperature effects, resulting in a decline in sealing performance and leakage. This is particularly obvious in hot and cold cycling and vibration environments. Moreover, the installation quality is highly dependent. The bolt tightening sequence and torque uniformity requirements for flange connection are high. Otherwise, it is easy to cause uneven stress on the gasket and leakage. Clamp connection has strict requirements for groove processing accuracy and sealing ring installation. Summary of the Invention
[0006] Aiming at the deficiencies of the prior art, one of the purposes of the present invention is to provide a closed connection device for building HVAC pipelines that is not prone to leakage, not prone to heat loss and is easy to maintain.
[0007] The above application purpose of the present invention is achieved through the following technical solutions:
[0008] A closed connection device for building HVAC pipelines, comprising:
[0009] An insert, both ends of which are respectively communicated with the pipeline, and the insert is in interference fit with the pipeline;
[0010] An outer fitting, which includes a locking part and a screwing part;
[0011] The locking part fits with one end of the insert, and the other end of the locking part forms an avoidance groove with the insert;
[0012] One end of the screwing part can be rotatably connected to the pipeline, and the other end of the screwing part is threadedly connected to the embedded part.
[0013] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, the locking part includes an inner layer, an interlayer and an outer layer arranged in sequence from inside to outside;
[0014] The inner layer is attached to the embedded part, the interlayer is located between the inner layer and the outer layer, and an avoidance groove is formed between the outer layer and the inner layer.
[0015] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, a plurality of threaded holes are opened in the outer layer opposite to the avoidance groove.
[0016] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, the interlayer is made of a flexible material.
[0017] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, the embedded part is provided with an external thread, the screwing part is provided with an internal thread matching the embedded part, and a plurality of protrusions are provided at the position where the embedded part is provided with the external thread.
[0018] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, the outer side wall of the screwing part is provided with anti-slip lines.
[0019] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, the embedded part includes a communicating pipe and an outer packaging layer;
[0020] The communicating pipe serves as a channel for fluid circulation, and both ends thereof are respectively communicated with the pipeline. The outer packaging layer is sleeved outside the communicating pipe, and the outer packaging layer serves as a reference member for connecting the outer fitting.
[0021] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, a plurality of through holes are opened in the communicating pipe.
[0022] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, a drainage groove is provided on the end face of the through hole.
[0023] As a further embodiment of a building HVAC pipeline closed connection device disclosed by the present invention, a reinforcing block is provided at the position of the outer packaging layer where the avoidance groove is located.
[0024] In summary, the present invention includes at least one of the following beneficial technical effects:
[0025] 1. The locking part of the present invention forms an adaptive radial compression seal on the outer wall of the pipeline through methods such as bolt pressurization, flexible interlayer force conversion, and filling gaps with reinforcement blocks. The screwing end of the screwing part axially presses the end face of the pipeline by screw thread engagement, and combines with the mechanical self-locking effect generated by the convex part embedded in the thread pair, reducing the seal failure caused by thread retraction and solving the leakage problem of traditional flange and clamp connections under thermal cycle vibration conditions;
[0026] 2. With the design of through holes and drainage grooves, the fluid is only exposed within the wall thickness range of the connecting pipe, reducing heat loss at the connection point, and reducing pumping energy consumption and temperature control compensation costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 is the overall structural schematic diagram of an embodiment of a closed connection device for building heating and ventilation pipelines disclosed by the present invention;
[0028] Figure 2 is the front view of an embodiment of a closed connection device for building heating and ventilation pipelines disclosed by the present invention;
[0029] Figure 3 is Figure 2 the cross-sectional view of part A-A in
[0030] In the figure,
[0031] 01, pipeline;
[0032] 1, insert; 11, connecting pipe; 111, through hole; 112, drainage groove; 12, outer layer; 121, reinforcement block; 122, external thread; 123, convex part;
[0033] 2, outer fitting; 21, locking part; 211, inner layer; 212, interlayer; 213, outer layer; 214, avoidance groove; 215, threaded hole; 22, screwing part; 221, internal thread; 222, anti-slip pattern. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0034] The following further describes the present invention in detail with reference to the accompanying drawings.
[0035] Referring to Figures 1-3 , a closed connection device for building heating and ventilation pipelines disclosed by the present invention includes an insert 1 and an outer fitting 2.
[0036] Both ends of the insert 1 are respectively used for sealing and connecting adjacent pipes of the HVAC system to ensure the continuity and tightness of the fluid passage. The insert 1 includes a connecting pipe 11 and an outer layer 12. The connecting pipe 11 serves as the core passage for fluid flow, and its two ends are respectively connected to the pipe 01. The connecting pipe 11 is cylindrical, and the end face diameter of the connecting pipe 11 is slightly larger than the inner diameter of the pipe. The connecting pipe 11 is in interference fit with the pipe, and the interference amount is usually in the range of 0.1 - 0.3 mm, and it is designed and processed according to the actual use and installation scenario. The end of the connecting pipe 11 can be designed as a flat mouth or with a small leading chamfer for easy assembly. A ring-shaped boss or a thickened area can be provided near the end of the connecting pipe 11 as a limit for the interference press-in depth and a stress dispersion structure.
[0037] The outer layer 12 is tightly sleeved and fixed on the outside of the connecting pipe 11. As the core reference component for the insert 1 to dock, position, and transmit the fastening force with the outer component 2, it is preferably made of an engineering material with a significantly higher hardness than the base material of the connecting pipe 11, such as 45 steel, after quenching and tempering treatment, high-strength engineering plastic POM, or glass fiber-reinforced nylon, etc., to improve its wear resistance, compressive deformation ability, and the bearing strength of the contact surface with the outer component 2. The outer layer 12 and the connecting pipe 11 can be tightly combined by interference hot fitting, bonding, or integral molding process, that is, the connecting pipe 11 and the outer layer 12 form a rigid-flexible transition layer, which not only ensures the connection stiffness but also can absorb part of the pipe vibration and thermal stress.
[0038] As a specific implementation mode of a building HVAC pipe closed connection device disclosed in the present invention, a plurality of regularly arranged through holes 111 are uniformly opened along the axial direction of the connecting pipe 11. The number and size of the through holes 111 are determined according to the actual use and installation scenario. For example, if it is designed to be not less than 80% of the nominal flow cross-sectional area of the pipe, the number and diameter of the through holes 111 are appropriately increased to ensure that the pressure loss during fluid passage is within an acceptable range. Although the through holes 111 will cause a certain pressure loss when the fluid passes through, when the fluid flowing in the pipe passes through the through holes 111, it is only exposed to a small gap area within the wall thickness range of the connecting pipe 11, significantly reducing the exposed surface area where the core flow of the fluid directly contacts the external environment and undergoes forced convection heat transfer. At the same time, the thermal inertia of the connecting pipe 11 wall itself and the existence of its outer layer 12 form an effective thermal resistance that does not exist in the fully permeable structure, thereby reducing the heat loss of the fluid at the connection position or the intrusion of environmental heat, achieving a local heat preservation effect, and thus reducing the temperature loss of the fluid at the connection position.
[0039] Furthermore, the connecting pipe 11 may be provided with a shallow V-shaped drainage groove 112 at the fluid inlet and / or outlet edge of each through hole 111. The drainage groove 112 can enable the smooth edge of the groove to guide the fluid to transition smoothly when the fluid flows through the through hole 111, avoid forming a sharp separation zone at the orifice edge, thereby effectively suppressing the generation of eddy currents, reducing the local turbulence intensity and frictional loss, and reducing the fluid energy loss and potential cavitation / vibration noise.
[0040] Regarding the external mating part 2, as the core external fastening component, it includes a locking part 21 and a screwing part 22. The locking part 21 and the screwing part 22 act on both sides of the device respectively to achieve reliable connection, effective sealing of the insert 1 and the two end pipes, and resistance to axial pull-off and radial vibration.
[0041] The inner side of one end of the locking part 21 is attached to the outer layer 12 of the insert 1, and the inner side surface of the other end of the locking part 21 forms an avoidance groove 214 with the insert 1. The avoidance groove 214 is used to place the pipe. The opening width of the avoidance groove 214 is slightly larger than the outer diameter of the pipe to be connected, actually forming an assembly gap of about 0.5 - 2 mm to facilitate the smooth insertion of the pipe.
[0042] Specific but non-limiting, the locking part 21 includes an inner layer 211, a sandwich layer 212, and an outer layer 213 arranged in sequence from the inside to the outside. Among them, the inner layer 211 is attached to the insert 1. The inner layer 211, as the core load-bearing component that directly contacts the insert 1 and applies a pressing force, can be selected from materials with relatively high hardness and compressive strength, such as carbon steel or alloy steel with a hardness of HRC 35 - 45. The inner surface of the inner layer 211 in contact with the pipe can be designed as a smooth surface or a micro-arc surface to increase the contact area and reduce stress concentration. The sandwich layer 212 is located between the inner layer 211 and the outer layer 213, and flexible engineering materials with a high elastic modulus and certain damping characteristics, such as nitrile rubber, polyurethane, or high-strength fluororubber, can be selected. The function of the sandwich layer 212 is to absorb and buffer the vibration transmission of the pipe, and at the same time, it can also compensate for the uneven contact caused by manufacturing tolerances and pipe ovality, making the pressing force distribution more uniform. An avoidance groove 214 is formed between the outer layer 213 and the inner layer 211. Threaded holes 215 are provided at the position of the outer layer 213 where the avoidance groove 214 is located. When the pipe is located in the avoidance groove 214, the pipe is locked by passing a bolt through. The outer layer 213, as the main structural member that bears the bolt pre-tightening force and resists external loads, can be selected from materials with relatively high stiffness and strength, such as Q345B structural steel or other materials with equivalent performance. In the embodiment shown in the attached drawing, 3 threaded holes 215 are processed on the side wall of the outer layer 213 facing the avoidance groove 214 and are evenly distributed along the circumference. The axes of these threaded holes 215 are perpendicular to the axis of the pipe and are used to screw in high-strength socket head cap screws or stud bolts.
[0043] To make the fixation more reliable, the outer layer 12 is provided with a plurality of independent or continuous strip-shaped reinforcement blocks 121 at the position of the avoidance groove 214. The reinforcement blocks 121 are fixed to the surface of the outer layer 12 facing the avoidance groove 214 by pre-burial or vulcanization bonding. The reinforcement blocks 121 are made of a flexible material such as polyurethane or thermoplastic elastomer with a higher hardness and a smaller compression set than the interlayer 212. When the pipeline is located in the avoidance groove 214, when the pipeline is placed into the avoidance groove 214 and pressed by the locking bolt, the reinforcement blocks 121 are preferentially compressed and deformed, filling the space between the outer wall of the pipeline and the outer layer 12, forming a local high-compression stress area. The reinforcement blocks 121 can significantly improve the anti-slip ability of the locking part 21 on the surface of the pipeline. It is similar to an interference fit. At the same time, under high-vibration or thermal cycle conditions, the reinforcement blocks 121 can also maintain a reliable residual pressing force to prevent seal failure caused by bolt loosening.
[0044] Regarding the screwing part 22, one end thereof can be rotatably connected to the pipeline, and the other end of the screwing part 22 is threadedly connected to the insert 1. Specifically, the end of the screwing part 22 facing the insert 1 is machined with an internal thread 221, and the outer layer 12 of the insert 1 and its extended part are machined with an external thread 122 matching the internal thread 221 at the corresponding position. By rotating the screwing part 22, the rotational motion is converted into an axial linear motion by the helix angle of the thread pair, so that the screwing part 22 axially presses the pipeline port at its connecting end, thereby realizing the reliable fixation and sealing of the pipeline on this side.
[0045] On the cylindrical section of the insert 1 provided with the external thread 122, a number of evenly distributed axial protrusions 123 are machined along the circumferential direction. This is a loosening prevention design, and the height of the protrusions 123 is slightly higher than the thread crest. When the screwing part 22 is screwed in, the teeth of its internal thread 221 interact with these tiny protrusions 123 to cause local micro-deformation and embedding, thereby significantly increasing the screwing friction resistance and providing a self-locking effect after initial pre-tightening. At the same time, when there is a slight relative rotation trend of the thread pair due to vibration or temperature change, the protrusion 123 structure can effectively block this movement and play a mechanical anti-loosening role.
[0046] Furthermore, on the entire circumferential surface or a local holding area of the outer side wall of the screwing part 22, continuous or discontinuous anti-slip lines 222 with appropriate depths are roll-pressed, milled or cast, such as knurled straight lines, reticulations, pit arrays or spiral grooves. The anti-slip lines 222 can significantly increase the friction coefficient between the operator's hand or the installation tool and the surface of the screwing part 22, prevent slipping when applying the tightening torque, ensure operation safety and torque transmission efficiency, and at the same time facilitate manual pre-tightening and subsequent disassembly and maintenance. The depth of the lines needs to ensure effective anti-slip while being easy to clean.
[0047] The implementation principle of this embodiment is as follows:
[0048] After the pipe is placed in the avoidance groove 214 of the locking part 21, radial pressure is applied through the bolts of the outer layer 213. The flexible interlayer 212 converts the axial tension of the bolts into a uniform radial pressing force, pushing the inner layer 211 to tightly wrap the pipe. The reinforcement block 121 is compressed to fill the gap to form a local interference fit, achieving anti-slip locking. Then, the screwing part 22 is screwed with the external thread 122 of the insert 1 through the internal thread 221, pushing the end face of the pipe to axially press against the end of the insert 1, and realizing fixation by end face sealing. The convex 123 structure is embedded in the thread pair to increase the frictional resistance and prevent back-off.
[0049] Through the dual fixing mechanism of the radial flexible clamping of the locking part 21 and the axial rigid pressing of the screwing part 22, combined with the restricted heat preservation design of the through hole 111 and the optimization of the drainage and anti-loosening microstructures, the connection points of the HVAC pipes are not prone to leakage, heat loss, and are easy to maintain.
[0050] The embodiments of this specific implementation manner are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be covered within the protection scope of the present invention.
Claims
1. A closed connection device for building heating, ventilation and air conditioning pipelines, characterized in that: including an insert (1) with both ends communicating with the pipeline respectively, and the insert (1) is in interference fit with the pipeline; a combined part (2) including a locking part (21) and a screwing part (22); the locking part (21) is attached to one end of the insert (1), and a relief groove (214) is formed between the other end of the locking part (21) and the insert (1); one end of the screwing part (22) can be rotatably connected to the pipeline, and the other end of the screwing part (22) is threadedly connected to the insert (1).
2. The closed connection device for building HVAC pipelines according to claim 1, characterized in that: the locking part (21) includes an inner layer (211), a sandwich layer (212) and an outer layer (213) arranged in sequence from inside to outside; the inner layer (211) is attached to the insert (1), the sandwich layer (212) is located between the inner layer (211) and the outer layer (213), and the relief groove (214) is formed between the outer layer (213) and the inner layer (211).
3. The closed connection device for building HVAC pipelines according to claim 2, wherein: a plurality of threaded holes (215) are formed in the outer layer (213) opposite to the relief groove (214).
4. The closed connection device for building HVAC pipelines according to claim 2, characterized in that: the sandwich layer (212) is made of a flexible material.
5. The closed connection device for building HVAC pipelines according to claim 1, characterized in that: the insert (1) is provided with an external thread (122), the screwing part (22) is provided with an internal thread (221) matching with the insert (1), and a plurality of protrusions (123) are arranged at the position where the insert (1) is provided with the external thread (122).
6. The closed connection device for building HVAC pipelines according to claim 5, characterized in that: the outer side wall of the screwing part (22) is provided with anti-slip lines (222).
7. A closed connection device for building heating and ventilation pipes according to claim 1, characterized in that: the insert (1) includes a connecting pipe (11) and an outer layer (12); the connecting pipe (11) serves as a fluid flow channel with both ends communicating with the pipeline respectively, the outer layer (12) is sleeved outside the connecting pipe (11), and the outer layer (12) serves as a reference member for connecting the outer combined part (2).
8. The closed connection device for building HVAC pipes according to claim 7, characterized in that: a plurality of through holes (111) are formed in the connecting pipe (11).
9. The closed connection device for building HVAC pipelines according to claim 8, characterized in that: a drainage groove (112) is arranged on the end face of the through hole (111).
10. A building HVAC pipe closed connection device according to claim 7, characterized in that: a reinforcement block (121) is arranged at the position of the outer layer (12) corresponding to the relief groove (214).