A calibration conduit and calibration device for venturi flow calibration

Abstract

The present application relates to flow metering technical field, especially a kind of venturi flow calibration's calibration pipeline and calibration device, including pipe body and temperature detection mechanism, the temperature detection mechanism includes base, fastener, adjusting body and temperature detection unit, the protruding portion is provided on the peripheral wall of the pipe body, the distal end of fastener is connected with protruding portion by base, and the proximal end of fastener is connected with adjusting body.The present application can be along the axial adjustment channel and adjust the position of temperature detection unit in adjustment channel, make the detection position of temperature detection unit correspond with the standard venturi in opening state, accurately detect the temperature data of standard venturi, reduce detection error, realize the flexible adjustment of temperature detection position;Air is prevented from flowing out from adjustment channel simultaneously, improve the structural stability of temperature detection unit after position locking, avoid stress concentration, protect the structural safety of temperature detection unit, improve the use convenience of device.

Description

Technical Field

[0001] This invention relates to the field of flow measurement technology, and in particular to a calibration pipe and calibration device for venturi flow calibration. Background Technology

[0002] A high-pressure venturi tube refers to a high-flow-rate venturi tube commonly used in dynamic model testing, with a flow rate range of 0.5 kg / s to 5.5 kg / s and an operating pressure range of 0.5 MPa to 6 MPa. High-pressure venturi tubes must be calibrated before use to accurately measure gas flow. However, in the process of developing this invention, the applicant discovered that existing calibration devices capable of calibrating high-flow-rate venturi tubes exhibit relatively low calibration uncertainty during calibration testing. Summary of the Invention

[0003] The purpose of this invention is to provide a calibration pipe and calibration device for Venturi flow calibration, in order to solve the above-mentioned technical problems existing in the prior art, mainly including the following two aspects:

[0004] The first aspect of this invention provides a calibration pipe for Venturi flow calibration, comprising a pipe body and a temperature detection mechanism. The temperature detection mechanism includes a base, a fastening body, an adjusting body, and a temperature detection unit. A protrusion is provided on the peripheral wall of the pipe body. The distal end of the fastening body is connected to the protrusion via the base, and the proximal end of the fastening body is connected to the adjusting body. A first channel is provided on the adjusting body, and a second channel is provided on the fastening body. The inner diameter of the second channel matches the temperature detection unit. A third channel is provided on the base, and a fourth channel is provided on the protrusion. The fourth channel penetrates the pipe body radially. A first channel, a second channel, a third channel, and a fourth channel constitute an adjustment channel for housing a temperature detection unit. An adjustment cavity is provided between the fastener and the adjustment body. The adjustment cavity contains a fastening tube and at least two mating parts. The mating parts surround the temperature detection unit and have wedge-shaped surfaces that engage with the distal end of the fastening tube. The fastener and the adjustment body have a movable stroke along the axial direction of the adjustment channel to adjust the clamping force of the mating parts on the temperature detection unit. The proximal end of the fastening tube is connected to the adjustment body, and a gap is provided between the distal end of the fastening tube and the fastener.

[0005] Furthermore, a heat insulation cavity is provided on the distal inner wall of the third channel.

[0006] Furthermore, a first boss is provided on one of the distal end of the base and the proximal end of the protrusion, and a first groove matching the first boss is provided on the other of the distal end of the base and the proximal end of the protrusion, and the adjustment channel passes through the first boss.

[0007] Furthermore, a first annular sealing groove is provided on the far end face of the base, the first annular sealing groove surrounds the third channel, and the first annular sealing groove is used to place the first sealing ring.

[0008] And / or, a second annular sealing groove is provided on the near end face of the base, the second annular sealing groove surrounds the third channel, and the second annular sealing groove is used to place the second sealing ring.

[0009] Furthermore, a second boss is provided on one of the proximal end of the base and the distal end of the fastener, and a second groove matching the second boss is provided on the other of the proximal end of the base and the distal end of the fastener. An annular seal is provided between the inner walls of the second boss and the second groove along the axial direction of the adjustment channel.

[0010] Furthermore, an adjustment groove is provided at the distal end of the first channel, and a connecting part is provided at the proximal end of the fastener. The distal end of the adjustment groove and the connecting part are threaded together to realize the adjustment of the axial distance between the fastener and the adjustment body along the adjustment channel. The adjustment groove and the connecting part cooperate to form an adjustment cavity.

[0011] Furthermore, the adjusting body is provided with an operating part, which is used to adjust the distance between the fastening body and the adjusting body;

[0012] And / or, the inner wall of the second channel is provided with a sealing surface, which is used to seal against the peripheral wall of the temperature detection unit.

[0013] Furthermore, the protrusion is provided with a mounting hole, and the calibration pipe also includes a sealing cap. The mounting hole is used to cooperate with a fastener to achieve a fixed connection between the sealing cap and the protrusion, or a fixed connection between the base and the protrusion.

[0014] A second aspect of the present invention provides a calibration device for calibrating venturi flow rates, comprising a test pipe and a calibration pipe, wherein the test pipe and the calibration pipe are coaxially arranged sequentially along the airflow direction, a first mounting base is provided inside the test pipe, and a first fixing channel is provided on the first mounting base for mounting and fixing the venturi tube to be tested, the first fixing channel being used to install and fix the venturi tube to be tested, a second mounting base is provided inside the calibration pipe, and a plurality of second fixing channels are provided on the second mounting base for mounting and fixing a standard venturi tube, a sealing end cap is provided on the backflow side of the second mounting base, the sealing end cap being provided in a one-to-one correspondence with the second fixing channel, the sealing end cap being detachably connected to the second mounting base or the standard venturi tube, and the sealing end cap being used to block the second fixing channels.

[0015] Furthermore, the diameter of the calibration pipe is larger than the diameter of the pipe to be tested. The pipe to be tested is connected to the calibration pipe through a transition pipe. A first rectifier and a first mounting base are sequentially arranged in the pipe to be tested along the air flow direction. A second rectifier and a second mounting base are sequentially arranged in the calibration pipe along the air flow direction. Multiple temperature detection mechanisms are arranged between the second rectifier and the second mounting base.

[0016] Compared with the prior art, the present invention has at least the following technical effects:

[0017] This invention allows for axial adjustment of the temperature detection unit within the adjustment channel, aligning its detection position with that of a standard venturi tube in its open state. This enables accurate detection of the standard venturi tube's temperature data, avoiding errors caused by positional deviations in existing technologies and allowing for flexible adjustment of the temperature detection position. Furthermore, the temperature detection unit, locked in place by the adjusting body and the fastening solid, can withstand internal and external pressure differences without slipping, ensuring stable detection at the target position. Additionally, the sealed fit between the second channel on the fastening solid and the temperature detection unit not only prevents air leakage from the adjustment channel but also prevents accidental slippage of the temperature detection unit during position adjustment. This improves the structural stability of the temperature detection unit after locking, avoids stress concentration, protects the structural safety of the temperature detection unit, and enhances the ease of use of the device. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the calibration pipeline of the present invention;

[0020] Figure 2 This is a schematic diagram of the temperature detection mechanism of the present invention;

[0021] Figure 3 This is a schematic diagram of the internal structure of the temperature detection mechanism of the present invention;

[0022] Figure 4 This is a schematic diagram of the internal structure of the temperature detection mechanism of the present invention;

[0023] Figure 5 This is a schematic diagram of the connection structure between the temperature detection mechanism and the protrusion of the present invention;

[0024] Figure 6This is a schematic diagram of the calibration pipeline of the present invention from another perspective;

[0025] Figure 7 This is a schematic diagram of the calibration device of the present invention;

[0026] Figure 8 yes Figure 7 Sectional view along line AA;

[0027] In the picture:

[0028] 10. Pipe body; 110. Protrusion; 111. Fourth channel; 120. Base; 121. Third channel; 122. Insulation cavity; 123. First boss; 124. First annular sealing groove; 125. Second boss; 126. Second annular sealing groove; 130. Fastening body; 131. Second channel; 132. Connecting part; 140. Adjusting body; 141. First channel; 142. Adjusting cavity; 143. Fastening tube; 144. Components: 145. Operating unit; 150. Temperature detection unit; 160. Sealing cap; 170. Fixing component; 180. Annular seal; 20. Pipe to be tested; 210. Venturi tube to be tested; 220. First rectifier; 230. Second rectifier; 240. Second mounting base; 241. Second fixing channel; 242. Sealing end cap; 250. Standard venturi tube; 30. Transition pipe; 40. Outlet pipe; 50. Sliding guide rail. Detailed Implementation

[0029] The following description provides many different embodiments or examples for implementing various features of the invention. The elements and arrangements described in the specific examples below are only for concise expression of the invention and are merely examples, not intended to limit the invention.

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0031] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Furthermore, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0032] In this invention, unless otherwise expressly specified and limited, "above or below" a first feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on" the first feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the first feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] High-pressure venturi tubes refer to the high-flow-rate venturi tubes commonly used in dynamic model testing, with a flow rate range of 0.5 kg / s to 5.5 kg / s and an operating pressure range of 0.5 MPa to 6 MPa. High-pressure venturi tubes must be calibrated before use to accurately measure gas flow. Current technology for calibrating high-flow-rate venturi tubes typically uses fixed temperature acquisition points, failing to measure the temperature distribution across the entire flow channel. Furthermore, the temperature distribution within the flow channel is complex during venturi tube calibration. Even with a uniform airflow rectification design, it's impossible to achieve completely uniform temperature throughout the flow channel. This is especially true for calibration devices for high-flow-rate venturi tubes, where the flow channel cross-section temperature requires flexible, multi-point measurements to accurately characterize the gas temperature. During testing, the calibration device operates on high-pressure gas. Repeated disassembly and reassembly of components (temperature sensors) makes it difficult to ensure a tight seal. Moreover, the lack of holes or protrusions for connection or installation in the solid components, similar to temperature sensors, makes it difficult to guarantee secure installation and prevent ejection under high pressure. Therefore, this application provides a calibration pipe and calibration device for Venturi flow calibration that can flexibly adjust the detection position of the temperature sensor according to the measurement position requirements, and can also be well sealed and fastened, and can increase the calibration accuracy by improving the accuracy of temperature measurement, as described in the following embodiments.

[0034] Example 1:

[0035] This application provides a calibration pipe for Venturi flow calibration, such as... Figure 1 and Figure 6 As shown, it includes a tube body 10 and a temperature detection mechanism, such as Figures 2-5 As shown, the temperature detection mechanism includes a base 120, a fastener 130, an adjusting body 140, and a temperature detection unit 150. A protrusion 110 is provided on the peripheral wall of the tube 10. The distal end of the fastener 130 is connected to the protrusion 110 via the base 120, and the proximal end of the fastener 130 is connected to the adjusting body 140. A first channel 141 is provided on the adjusting body 140, and a second channel 131 is provided on the fastener 130. The inner diameter of the second channel 131 matches that of the temperature detection unit 150. A third channel 121 is provided on the base 120, and a fourth channel 111 is provided on the protrusion 110. The fourth channel 111 penetrates the tube 10 radially. The first channel 141, the second channel 131, and the third channel 150 are connected to the tube 10. The channel 121 and the fourth channel 111 form an adjustment channel for housing the temperature detection unit 150. An adjustment cavity 142 is provided between the fastening solid 130 and the adjustment body 140. The adjustment cavity 142 is provided with a fastening tube 143 and at least two mating parts 144. The mating parts 144 are arranged around the temperature detection unit 150 and have a wedge-shaped surface. The wedge-shaped surface is used to mate with the distal end of the fastening tube 143. The fastening solid 130 and the adjustment body 140 have a movable stroke along the axial direction of the adjustment channel to adjust the clamping force of the mating parts 144 on the temperature detection unit 150. The proximal end of the fastening tube 143 is close to the adjustment body 140, and there is a gap between the distal end of the fastening tube 143 and the fastening solid 130.

[0036] When calibrating and testing a venturi tube, such as Figure 7As shown, the Venturi tube 210 to be tested is installed inside the pipe 20 to be tested. Based on the calibration flow requirements, the number of standard Venturi tubes 250 that need to be in the open state is determined. Based on the required open standard Venturi tubes 250, the regulating body 140 is controlled so that the mating part 144 does not directly clamp the temperature detection unit 150. At this time, the operator can adjust the position of the temperature detection unit 150 within the regulating channel along its axial direction, causing the detection point at the distal end of the temperature detection unit 150 to shift radially along the pipe body 10. This adjusts the temperature detection position within the pipe body 10, ensuring that the detection position of the temperature detection unit 150 corresponds to the open standard Venturi tube 250, thus achieving... It can accurately detect the temperature data of the standard Venturi tube 250, avoiding the problem of temperature detection errors caused by deviations in the temperature detection position in existing technologies, which in turn affects the calibration accuracy. This allows for flexible adjustment of the temperature detection position. Furthermore, after adjusting the position of the temperature detection unit 150, the adjusting body 140 is controlled again to change the distance between the adjusting body 140 and the fastening solid 130. During the adjustment process, as the distance between the adjusting body 140 and the fastening solid 130 decreases, the adjusting body 140 forces the fastening tube 143 to move towards the fastening solid 130. Based on the engagement between the distal end of the fastening tube 143 and the wedge-shaped surface on the mating part 144, the mating part 144 is forced towards the adjustment channel. As the axis moves, multiple mating parts 144 work together. With the distance between the adjusting body 140 and the fastening solid 130 decreasing, they gradually tighten around the temperature detection unit 150 in the adjusting channel, locking its position. This ensures that, under high pressure, the position-adjustable temperature detection unit 150, locked in place by the adjusting body 140 and the fastening solid 130, can withstand the internal and external pressure difference without slipping, guaranteeing stable detection at the target position. Simultaneously, the sealed fit between the second channel 131 on the fastening solid 130 and the temperature detection unit 150 not only prevents air from escaping from the adjusting channel but also allows the temperature detection unit 150 to maintain its position. The stress area is not limited to the mating part 144, but also includes the interaction force between the inner wall of the second channel 131 and the peripheral wall of the temperature detection unit 150. The second channel 131 increases the frictional resistance of the temperature detection unit 150 moving axially along the adjustment channel. This can prevent the temperature detection unit 150 from accidentally slipping when adjusting its position, improve the structural stability of the temperature detection unit 150 after locking its position, and disperse the stress on the temperature detection unit 150 caused by the internal and external pressure difference by the inner wall of the second channel 131. This avoids stress concentration at the location corresponding to the mating part 144, protects the structural safety of the temperature detection unit 150, and improves the ease of use of the device.

[0037] In addition, by providing a protrusion 110 on the tube body 10, the structural strength of the tube body 10 can be enhanced, offsetting the negative structural strength effect caused by opening the fourth channel 111, allowing the calibration pipeline to withstand the high-pressure calibration environment without damage, and improving the safety and stability of the device.

[0038] It should be noted that the temperature detection unit 150 is existing technology. Specifically, the temperature detection unit 150 can be a cylindrical structure. The sensor used to realize temperature detection is located at the far end of the cylinder, inside the tube 10, and the signal connector used to realize the transmission of detection data is located at the near end of the cylinder, outside the tube 10. The cylinder is preferably made of metal, specifically steel.

[0039] To improve temperature detection accuracy, such as Figures 2-5 As shown, a heat insulation cavity 122 can be provided on the inner wall of the far end of the third channel 121. In order to achieve a stable connection between the temperature detection mechanism and the tube body 10, the base 120 is generally made of metal. Since metal has good thermal conductivity, and the base 120 is close to the sensor at the far end of the temperature detection unit 150, in order to avoid the external ambient temperature being conducted to the temperature detection unit 150 through the base 120 and affecting the detection accuracy of the temperature detection unit 150, a heat insulation cavity 122 is provided on the inner wall of the far end of the third channel 121. The heat insulation cavity 122 reduces the heat transfer between the base 120 and the temperature detection unit 150, thereby reducing the impact of the external environment on the detection accuracy of the temperature detection unit 150, improving the accuracy of temperature detection, and achieving precise calibration.

[0040] The insulation cavity 122 can be directly filled with insulation material to reduce heat transfer, or it can be insulated with air; no specific limitation is made here.

[0041] In some embodiments, the solid 130 and / or the regulating body 140 may be made of heat-insulating material to reduce the impact of the external environment on the detection accuracy of the temperature detection unit 150.

[0042] To improve installation convenience, a first protrusion 123 can be provided on the far end of the base 120, and a first groove matching the first protrusion 123 can be provided on the near end of the protrusion 110. The adjustment channel passes through the first protrusion 123. When installing the temperature detection mechanism onto the pipe body 10, the base 120 can be placed on the protrusion 110 first, and the first protrusion 123 can be inserted into the first groove. Through the cooperation of the first protrusion 123 and the first groove, the base 120 and the pipe body 10 are pre-fixed. Then, the base 120 can be fixed onto the pipe body 10 with bolts. At the same time, since the adjustment channel passes through the first protrusion 123, the corresponding heat insulation cavity 122 extends through the first protrusion 123, increasing the effective heat insulation area of ​​the temperature detection unit 150 and further reducing the influence of the external environment on the detection accuracy of the temperature detection unit 150.

[0043] To improve installation convenience, a first boss 123 can be provided at the proximal end of the protrusion 110, and a first groove matching the first boss 123 can be provided at the distal end of the base 120. The adjustment channel passes through the first boss 123. Through the cooperation of the first boss 123 and the first groove, the base 120 and the tube 10 are pre-fixed, thereby improving the installation convenience of the device.

[0044] To improve the sealing performance of the temperature detection mechanism, a first annular sealing groove 124 can be provided on the far end face of the base 120. The first annular sealing groove 124 surrounds the third channel 121 and is used to place the first sealing ring. Through sealing fit, the connection sealing performance between the base 120 and the protrusion 110 is enhanced, preventing air from flowing out from the gap between the base 120 and the protrusion 110, thereby improving the sealing performance of the device.

[0045] To improve the sealing performance of the temperature detection mechanism, a second annular sealing groove 126 can be provided on the near end face of the base 120. The second annular sealing groove 126 surrounds the third channel 121 and is used to place the second sealing ring. Through sealing fit, the connection sealing performance between the base 120 and the fastener 130 is enhanced, preventing air from flowing out from the gap between the base 120 and the fastener 130, thereby improving the sealing performance of the device.

[0046] To improve installation convenience, a second boss 125 can be provided on the near end of the base 120, and a second groove matching the second boss 125 can be provided on the far end of the fastener 130. The second boss 125 and the second groove are used to achieve pre-fixation, which facilitates the fixed connection between the fastener 130 and the base 120. At the same time, along the axial direction of the adjustment channel, an annular seal 180 is provided between the inner walls of the second boss 125 and the second groove to achieve a sealing fit between the base 120 and the fastener 130, further preventing air from flowing out from the gap between the base 120 and the fastener 130. In addition, it is preferable that the annular seal 180 is sleeved on the temperature detection unit 150. The annular seal 180 and the temperature detection unit 150 are sealed together to prevent air from entering the second channel 131 from the heat insulation cavity 122, preventing air from flowing out from the adjustment channel and ensuring the sealing performance of the tube body 10.

[0047] To improve installation convenience, a second boss 125 can be provided at the far end of the fastener 130, and a second groove matching the second boss 125 can be provided at the near end of the base 120. The second boss 125 and the second groove are used to achieve pre-fixation, which facilitates the fixed connection of the fastener 130 and the base 120. Along the axial direction of the adjustment channel, an annular seal 180 is provided between the inner walls of the second boss 125 and the second groove to enhance the sealing performance, prevent air from entering the second channel 131 from the heat insulation cavity 122, prevent air from flowing out from the adjustment channel, and ensure the sealing performance of the tube body 10.

[0048] To achieve the locking state adjustment of the temperature detection unit 150, an adjustment groove can be provided at the distal end of the first channel 141, and a connecting part 132 is provided at the proximal end of the fastening body 130. The distal end of the adjustment groove and the connecting part 132 are threadedly connected to achieve the adjustment of the axial distance between the fastening body 130 and the adjusting body 140 along the adjustment channel. The inner wall of the adjustment groove and the connecting part 132 cooperate to form the adjustment cavity 142. By rotating the adjusting body 140, the distance between the fastening body 130 and the adjusting body 140 is changed. When the distance between the fastening body 130 and the adjusting body 140 is reduced, the fastening force of the fastening tube 143 on the temperature detection unit 150 through the mating part 144 increases. When the distance between the fastening body 130 and the adjusting body 140 is increased, the fastening force of the fastening tube 143 on the temperature detection unit 150 through the mating part 144 decreases.

[0049] To adjust the distance between the fastener 130 and the adjusting body 140, an operating part 145 can be provided on the adjusting body 140. By cooperating with the operating part 145 using a wrench with a force detection function, the interaction force between the adjusting body 140 and the wrench can be detected during the rotation of the adjusting body 140. Accordingly, it can be determined whether the clamping force of the mating part 144 on the temperature detection unit 150 has reached the preset value. This prevents the temperature detection unit 150 from being damaged due to excessive clamping force when the temperature detection unit 150 is stably locked, thereby improving the safety and convenience of the device.

[0050] Specifically, the inner wall of the second channel 131 is provided with a sealing surface, which is used to seal with the peripheral wall of the temperature detection unit 150 to prevent air from entering the first channel 141 from the heat insulation cavity 122, and to prevent gas exchange between the external environment and the inside of the tube 10 through the adjustment channel.

[0051] To achieve a fixed connection between the base 120 and the protrusion 110, the protrusion 110 is provided with a mounting hole for engaging with a fastener 170. The fastener 170 passes through the base 120 and connects with the mounting hole, thus achieving a fixed connection between the base 120 and the protrusion 110. When a temperature detection mechanism is not required on the protrusion 110, the fastener 170 can pass through a sealing cap 160 and connect with the mounting hole. The sealing cap 160 can then be used to seal the fourth channel 111, preventing air from leaking out of the tube 10 from the fourth channel 111 while ensuring a fixed connection between the sealing cap 160 and the protrusion 110. Preferably, the fastener 170 is a bolt or screw.

[0052] Example 2:

[0053] This application provides a calibration device, such as... Figure 7 and Figure 8 As shown, a method for calibrating venturi flow includes a test pipe 20 and a calibration pipe as described in Example 1. The test pipe 20 and the calibration pipe are coaxially arranged sequentially along the airflow direction. A first mounting base is provided inside the test pipe 20, and a first fixing channel is provided on the first mounting base. The first fixing channel is used to install and fix the venturi tube 210 under test. A second mounting base 240 is provided inside the calibration pipe, and a plurality of second fixing channels 241 are provided on the second mounting base 240. The second fixing channels 241 are used to install and fix a standard venturi tube 250. A sealing end cap 242 is provided on the backflow side of the second mounting base 240. The sealing end cap 242 is provided in a one-to-one correspondence with the second fixing channels 241. The sealing end cap 242 is detachably connected to the second mounting base 240 or the standard venturi tube 250 and is used to block the second fixing channels 241.

[0054] When calibrating and testing a venturi tube, the venturi tube 210 to be tested is installed on the first fixed channel. Based on the calibration flow requirements, the number of standard venturi tubes 250 that need to be in the open state is determined, and the sealing end cap 242 is removed and installed. The number of standard venturi tubes 250 in the open state that meet the calibration flow requirements is left, so that the calibration flow can be flexibly adjusted. For the blocked standard venturi tubes 250, since the end face is directly blocked, the high pressure difference can ensure the efficient sealing of the standard venturi tubes 250, avoiding the problem of poor sealing effect of valves in the existing technology under high pressure. Moreover, the sealing end cap 242 is located on the back flow surface of the second mounting base 240, so it will not affect the gas flow of other standard venturi tubes 250. Then, a stable airflow is introduced into the input end of the pipe 20 to be tested, and temperature and pressure data inside the pipe 20 are collected. The temperature and pressure data inside the pipe are calibrated, as well as the venturi temperature data of the venturi tube 210 to be tested and the standard venturi tube 250. By processing and analyzing the collected data, the calibration analysis results can be obtained, and the accurate calibration of the venturi tube to be tested can be achieved.

[0055] Specifically, the diameter of the tube body 10 in the calibration pipeline is larger than the diameter of the test pipeline 20. The test pipeline 20 is connected to the calibration pipeline through a transition pipeline 30. A first rectifier 220 and a first mounting base are sequentially arranged in the test pipeline 20 along the air flow direction. At least one temperature detection mechanism is arranged between the first rectifier 220 and the first mounting base. A second rectifier 230 and a second mounting base 240 are sequentially arranged in the calibration pipeline along the air flow direction. Multiple temperature detection mechanisms are arranged between the second rectifier 230 and the second mounting base 240.

[0056] Since all standard Venturi tubes 250 are installed in a single pipe, the piping structure of the calibration device is simplified. Only one pipe needs to be opened to operate all the standard Venturi tubes 250, facilitating their management and maintenance. Furthermore, because all the standard Venturi tubes 250 are in the same airflow environment, the increased pipe diameter of the calibration pipe allows for a smaller proportion of the temperature detection unit 150 in the gas flow cross-section when it is installed in the airflow environment for testing. Compared to the existing technology where one branch corresponds to one standard Venturi tube 250, the temperature detection unit 150 provides better control over airflow. With almost no impact, the temperature detection unit 150 can be placed close to the standard venturi tube 250 to achieve accurate detection of the ambient temperature of the standard venturi tube 250. Moreover, the calibration channel can provide more installation positions for detection units in the circumferential and axial directions. Multiple protrusions 110 for installing temperature detection mechanisms can be set on the circumferential wall of the calibration pipe along the axial direction, or multiple protrusions 110 for installing temperature detection mechanisms can be set on the circumferential wall of the calibration pipe on the same circumference, so as to achieve multi-point detection, reduce the detection error of key calibration parameters such as temperature and pressure, and thus improve the detection accuracy.

[0057] In some embodiments, the calibration device further includes an outlet pipe 40 and a sliding guide rail 50. The input end of the outlet pipe 40 is detachably connected to the output end of the calibration pipe. The output end of the outlet pipe 40 is used to connect to an exhaust port. The diameter of the outlet pipe 40 gradually decreases along the airflow direction. The outlet pipe 40 and the calibration pipe are slidably connected to the sliding guide rail 50 to facilitate quick assembly and disassembly of the outlet pipe 40 and the standard safety pipe, and quick installation and removal of the sealing end cap 242. At the same time, by designing the outlet pipe 40 with a variable diameter, on the one hand, the mass and volume of the outlet pipe 40 are reduced, thereby reducing the resistance to pushing the outlet pipe 40 to slide. On the other hand, it can be adapted to the exhaust port for easy connection with the exhaust port.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A calibration pipe for Venturi flow calibration, characterized in that, The device includes a tube body and a temperature detection mechanism. The temperature detection mechanism includes a base, a fastening body, an adjusting body, and a temperature detection unit. A protrusion is provided on the peripheral wall of the tube body. The distal end of the fastening body is connected to the protrusion via the base, and the proximal end of the fastening body is connected to the adjusting body. A first channel is provided on the adjusting body, a second channel is provided on the fastening body, the inner diameter of the second channel matching the temperature detection unit, a third channel is provided on the base, and a fourth channel is provided on the protrusion. The fourth channel penetrates the tube body radially. The first, second, and third channels... The first channel and the fourth channel form an adjustment channel for housing the temperature detection unit. An adjustment cavity is provided between the fastener and the adjustment body. The adjustment cavity contains a fastening tube and at least two mating parts. The mating parts surround the temperature detection unit and have wedge-shaped surfaces that engage with the distal end of the fastening tube. The fastener and the adjustment body have a movable stroke along the axial direction of the adjustment channel to adjust the clamping force of the mating parts on the temperature detection unit. The proximal end of the fastening tube is connected to the adjustment body, and a gap is provided between the distal end of the fastening tube and the fastener.

2. The calibration pipeline as described in claim 1, characterized in that, A heat insulation cavity is provided on the inner wall of the distal end of the third channel.

3. The calibration pipeline as described in claim 2, characterized in that, A first boss is provided on one of the distal end of the base and the proximal end of the protrusion, and a first groove matching the first boss is provided on the other of the distal end of the base and the proximal end of the protrusion, and the adjustment channel passes through the first boss.

4. The calibration pipeline as described in claim 2, characterized in that, A first annular sealing groove is provided on the far end face of the base. The first annular sealing groove surrounds the third channel and is used to place the first sealing ring. And / or, a second annular sealing groove is provided on the near end face of the base, the second annular sealing groove surrounds the third channel, and the second annular sealing groove is used to place the second sealing ring.

5. The calibration pipeline as described in claim 2, characterized in that, A second boss is provided on one of the proximal end of the base and the distal end of the fastener, and a second groove matching the second boss is provided on the other of the proximal end of the base and the distal end of the fastener. An annular seal is provided between the inner walls of the second boss and the second groove along the axial direction of the adjustment channel.

6. The calibration pipeline as described in any one of claims 1 to 5, characterized in that, An adjustment groove is provided at the distal end of the first channel, and a connecting part is provided at the proximal end of the fastener. The distal end of the adjustment groove and the connecting part are threaded together to realize the adjustment of the axial distance between the fastener and the adjustment body along the adjustment channel. The adjustment groove and the connecting part cooperate to form an adjustment cavity.

7. The calibration pipeline as described in claim 6, characterized in that, The adjusting body is provided with an operating part, which is used to adjust the distance between the fastening body and the adjusting body; And / or, the inner wall of the second channel is provided with a sealing surface, which is used to seal against the peripheral wall of the temperature detection unit.

8. The calibration pipeline as described in any one of claims 1 to 5, characterized in that, The protrusion is provided with a mounting hole, and the calibration pipe also includes a sealing cap. The mounting hole is used to cooperate with a fastener to achieve a fixed connection between the sealing cap and the protrusion, or a fixed connection between the base and the protrusion.

9. A calibration device for venturi flow calibration, characterized in that, The device includes a test pipe and a calibration pipe as described in any one of claims 1 to 8. The test pipe and the calibration pipe are coaxially arranged sequentially along the airflow direction. A first mounting base is provided inside the test pipe, and a first fixing channel is provided on the first mounting base. The first fixing channel is used to install and fix the venturi tube under test. A second mounting base is provided inside the calibration pipe, and a plurality of second fixing channels are provided on the second mounting base. The second fixing channels are used to install and fix a standard venturi tube. A sealing end cap is provided on the backflow side of the second mounting base. The sealing end cap is provided in a one-to-one correspondence with the second fixing channel. The sealing end cap is detachably connected to the second mounting base or the standard venturi tube and is used to block the second fixing channels.

10. The calibration apparatus as described in claim 9, characterized in that, The diameter of the calibration pipe is larger than that of the pipe to be tested. The pipe to be tested is connected to the calibration pipe through a transition pipe. A first rectifier and a first mounting base are arranged sequentially in the air flow direction inside the pipe to be tested. A second rectifier and a second mounting base are arranged sequentially in the air flow direction inside the calibration pipe. Multiple temperature detection mechanisms are arranged between the second rectifier and the second mounting base.

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