Flaring conduit pipeline installation method

Abstract

The invention discloses a flaring conduit pipeline installation method which comprises the following steps: in a free ground state, smearing lubricating grease at an assembly position of a pipeline, tightening a flaring conduit, loosening and analyzing the form of a conduit sealing ring; according to the shape of the sealing ring, the installation angle and tightening torque between the flaring guide pipe and the flat pipe nozzle in the pipeline are adjusted till the shape of the sealing ring meets the requirement, and the assembly position between the flaring guide pipe and the flat pipe nozzle is marked on the flaring guide pipe and the flat pipe nozzle; and the flaring guide pipe is laid to the actual installation position, lubricating grease is smeared, and installation is conducted. On the basis of analysis of a torsion-tension relation of connection of the flaring conduit, measures of adding lubrication and pre-assembling on the ground are adopted, so that the influence of manufacturing errors of all parts of the flaring pipeline on the sealing performance after installation is eliminated, and the situation that the flaring conduit needs to be repeatedly disassembled and assembled and subjected to sealing performance detection after installation due to the fact that the sealing performance does not reach the standard is avoided; the sealing performance of the flaring guide pipe after installation is effectively improved, and the installation efficiency and quality of the flaring guide pipe of a pipeline system are guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of catheter assembly technology, specifically relating to a method for installing flared catheters. Background Technology

[0002] Flared connections in mechanical equipment pipelines are one of the most widely used connection methods in pipeline systems, serving the functions of air and liquid passage. Flared connection pipelines are rigid pipeline connections consisting of four parts: pipe fitting, outer nut, flat nozzle, and flared conduit. When connecting the flared conduit, the outer nut is pressed tightly against the threaded connection on the pipe fitting. The inner conical surface of the flared end of the conduit fits tightly against the outer conical surface of the pipe fitting, forming a sealing ring.

[0003] When installing flared conduits in a piping system, it is essential to ensure that the mating condition (including coaxiality, axial deviation, and radial deviation) between the flared conduit and the pipe fitting meets the requirements; otherwise, its sealing performance will be affected. For flared connection pipelines within mechanical equipment, their sealing performance is also affected by the manufacturing dimensional deviations, surface roughness, lubrication methods during assembly, and installation techniques of the various components of the flared connection pipeline. Therefore, due to the numerous factors affecting the sealing performance of flared conduits and the lack of systematic installation guidance, operators often need to spend considerable time repeatedly disassembling, replacing, and adjusting the flared conduits to ensure their sealing performance. Summary of the Invention

[0004] The purpose of this invention is to provide a method for installing flared conduit pipes, so as to solve the problem that repeated disassembly and assembly are required during the assembly of flared conduits, making it difficult to ensure assembly quality.

[0005] This invention is achieved through the following technical solution: A method for installing a flared conduit, the conduit comprising a flared conduit, a flat nozzle, an outer nut, and a pipe fitting, wherein the flat nozzle is fitted onto the flared conduit, and the pipe fitting and flat nozzle are connected respectively by the outer nut, pressing the flared end of the flared conduit against the conical interface of the pipe fitting, forming a sealing ring between the inner conical surface of the flared end of the flared conduit and the outer conical surface of the conical connector; including the following steps: With the pipe in a free state on the ground, apply grease to the assembly position of the pipeline, tighten the flared conduit, then loosen it and analyze the shape of the conduit sealing ring. Adjust the installation angle and tightening torque between the flared conduit and the flat nozzle in the pipeline according to the shape of the sealing ring until the shape of the sealing ring meets the requirements, and mark the assembly position between the two on the flared conduit and the flat nozzle. Lay the flared conduit to the actual installation location, apply lubricant, and then install it.

[0006] In some embodiments of the present invention, the sealing ring shape is used to determine whether the sealing ring shape meets the requirements. When the sealing ring shape does not meet the requirements, the flared guide tube is rotated and the installation angle between the flared guide tube and the flat nozzle is adjusted until the sealing ring shape meets the requirements.

[0007] In some embodiments of the present invention, when the sealing ring is continuous, has a uniform width, and the width of the sealing ring meets the requirements, the shape of the sealing ring is determined to meet the requirements.

[0008] In some embodiments of the present invention, when the sealing ring has a uniform width but multiple breaks, the flat nozzle is rotated to avoid the break points and the tightening torque is increased; the flared guide tube is tightened repeatedly and the shape of the sealing ring is checked until the shape of the sealing ring meets the requirements.

[0009] In some embodiments of the present invention, when the sealing ring has a uniform width but one break point, the flat nozzle is rotated to avoid the break point and the tightening torque is increased; the tightening operation of the flared guide tube is repeated, and the shape of the sealing ring is checked until the shape of the sealing ring meets the requirements.

[0010] In some embodiments of the present invention, when the sealing ring has a uniform width but two breaks, the flat nozzle is rotated 90° and the tightening torque is increased; the tightening operation of the flared guide tube is repeated, and the shape of the sealing ring is checked until the shape of the sealing ring meets the requirements.

[0011] In some embodiments of the present invention, when the sealing ring is continuous but the width is uneven, the position corresponding to the minimum width of the sealing ring is marked on the flared guide tube and the flat nozzle, the flat nozzle is rotated 180°, and the tightening torque is adjusted according to the minimum width of the sealing ring; the flared guide tube is tightened repeatedly, and the shape of the sealing ring is checked until the shape of the sealing ring meets the requirements.

[0012] In some embodiments of the present invention, when the pipeline is pre-installed for the first time, the flat nozzle is rotated around the central axis of the flared conduit to check whether there are any tight points between the flared conduit and the flat nozzle, and the position of the tight point is assembled; when tightening the assembly on the ground, the installation angle between the flat nozzle and the flared conduit is adjusted to offset the position of the tight point.

[0013] In some embodiments of the present invention, the torsional relationship of the flared conduit is analyzed to establish the relationship between the axial preload and the tightening torque during assembly. The tightening torque is the sum of the frictional torques of the first contact pair, the second contact pair, the third contact pair, the fourth contact pair, the fifth contact pair, and the sixth contact pair; the first contact pair is the helical pair between the outer nut and the pipe fitting; the second contact pair is the contact pair formed by the inner conical surface of the flared conduit and the corresponding conical surface of the pipe fitting; the third contact pair is the contact pair formed by the outer conical surface of the flared conduit and the inner conical surface of the flat nozzle head; the fourth contact pair is the contact pair formed by the flat nozzle and the side annular surface of the outer nut; the fifth contact pair is the contact pair formed by the inner surface of the circular hole at the tail end of the outer nut and the outer cylindrical surface of the flat nozzle; the sixth contact pair is the contact pair formed by the straight section of the flared conduit and the inner cylindrical surface of the flat nozzle.

[0014] In some embodiments of the present invention, the relationship between the axial preload and the tightening torque is expressed as follows: T = T1 + T2 + T3 + T4 + T5 + T6; Where T1, T2, T3, T4, T5, and T6 are the frictional torques of the first contact pair, the second contact pair, the third contact pair, the fourth contact pair, the fifth contact pair, and the sixth contact pair, respectively; and T2=0, T5=0, and T6=0. get: ; Among them, F a α is the axial preload, T is the tightening torque, P is the thread pitch, µ1 is the friction coefficient of the first contact pair, r1 is the equivalent radius of the first contact pair, β is half of the thread profile angle of the helical pair, µ3 is the friction coefficient of the third contact pair, r3 is the equivalent radius of the third contact pair, α3 is half of the outer cone angle of the flared guide tube, µ4 is the friction coefficient of the fourth contact pair, and r4 is the equivalent radius of the fourth contact pair.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: Based on the analysis of the torsion relationship of flared conduit connections, this invention adopts measures such as increased lubrication and ground pre-assembly to eliminate the impact of manufacturing errors of various components of the flared pipeline on its sealing performance after installation. This avoids the need for repeated disassembly and reassembly and sealing tests after the flared conduit is installed due to substandard sealing performance, effectively improving the sealing performance of the flared conduit after installation and ensuring the efficiency and quality of flared conduit installation in the pipeline system. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart illustrating the installation process of the flared catheter in an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the flared pipe assembly structure in an embodiment of the present invention.

[0019] Figure 3 for Figure 2 Sectional view along line AA.

[0020] Figure 4 This is a flowchart of the ground pre-assembly steps in an embodiment of the present invention.

[0021] Figure 5 These are schematic diagrams illustrating different forms of the pre-assembled sealing ring on the ground according to embodiments of the present invention; wherein, The width of the sealing ring, Minimum width of the sealing ring, This represents the maximum width of the sealing ring.

[0022] Figure 6 This is a schematic diagram illustrating the rotation of the flat nozzle and the marking on the flat nozzle and the flared guide tube according to an embodiment of the present invention.

[0023] in: 1. Flared tube, 2. Flat nozzle, 3. Outer nut, 4. Pipe fitting. Detailed Implementation

[0024] 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 some embodiments of the present invention, but not all embodiments.

[0025] This invention analyzes the torsion relationship during the connection of flared conduits and forms a set of scientific and standardized installation process methods. By adopting measures such as increased lubrication and ground pre-assembly, the influence of manufacturing errors of various pipeline components on their sealing performance after installation is eliminated, effectively improving the sealing performance of flared conduits after installation and ensuring the efficiency and quality of flared conduit installation in pipeline systems.

[0026] In some embodiments of the present invention, the method for installing a flared conduit includes the following steps: S100. Pre-installation inspection: Remove the sealing and wrapping materials from each connection of the pipeline and inspect the appearance of each connection. S200, flared catheter flushing: The inner wall of the catheter is flushed with clean gas at a certain pressure; S300, Ground Pre-assembly: In the free state on the ground, apply grease to the assembly position of the pipeline, tighten the flared conduit, then loosen it and analyze the shape of the conduit sealing ring, and judge whether it meets the requirements based on the shape of the sealing ring. S400, Laying and Connection: Lay the flared conduit in the specified position, apply grease, and initially connect the flared conduit and its fixing points; S500, Tightening and Fixing: Check and adjust the assembly status of the flared guide tube, maintain the pre-assembled position of the flat nozzle, and perform the final tightening and fixing operation on the flared guide tube. S600, Safety Locking: Implement safety locking measures at the connection of the flared tube according to the specifications, and wipe the markings made on the flared tube and flat nozzle. S700 Assembly Status Inspection: Inspect the condition of the flared conduit after assembly, including the correctness of the connection, the clearance with the surroundings, the standardization of the safety device, and the surface quality of the flared conduit and accessories. S800, Sealing Inspection: Verify the sealing of the pipeline, and detect and eliminate any leaks at the connection of the flared conduit.

[0027] The flared conduit in this invention is a flared connection conduit for mechanical equipment piping systems. Its structure and manufacturing conform to standard specifications, such as the HB4-1 series, see reference. Figure 2 and Figure 3 The piping system includes a flared conduit 1, a flat nozzle 2, an outer nut 3, and a pipe fitting 4. The flat nozzle is fitted onto the flared conduit, and the pipe fitting and flat nozzle are connected by the outer nut, pressing the flared end of the flared conduit onto the conical interface of the pipe fitting. A sealing ring is formed between the inner conical surface of the flared end of the flared conduit and the outer conical surface of the conical connector.

[0028] Based on the analysis of the torque-tension relationship of the flared conduit connection, during the tightening process, the tightening torque needs to overcome the frictional torque of each contact pair, and finally form the axial preload force for the flared conduit to play a sealing role.

[0029] Therefore, the tightening torque is expressed as: T = T1 + T2 + T3 + T4 + T5 + T6; Wherein, T1, T2, T3, T4, T5, and T6 are the frictional torques of the first contact pair, the second contact pair, the third contact pair, the fourth contact pair, the fifth contact pair, and the sixth contact pair, respectively; The first contact pair is the helical pair between the outer nut 3 and the pipe fitting 4; the second contact pair is the contact pair formed by the inner conical surface of the flared conduit 1 and the corresponding conical surface of the pipe fitting 4; the third contact pair is the contact pair formed by the outer conical surface of the flared conduit 1 and the inner conical surface of the head of the flat nozzle 2; the fourth contact pair is the contact pair formed by the side annular surface of the flat nozzle 2 and the outer nut 3; the fifth contact pair is the contact pair formed by the inner surface of the circular hole at the tail end of the outer nut 3 and the outer cylindrical surface of the flat nozzle 2; the sixth contact pair is the contact pair formed by the straight part of the flared conduit 1 and the inner cylindrical surface of the flat nozzle 2.

[0030] Because of the relative sliding between the outer nut 3 and the flat nozzle 2, the round hole at the tail end of the outer nut 3 is generally larger than the outer diameter of the flat nozzle 2. There is no positive pressure between the straight part of the flared guide tube 1 and the cylindrical inner surface of the flat nozzle 2. The contact point between the flared guide tube 1 and the pipe joint 4 is static friction. Therefore, T2=0, T5=0, and T6=0.

[0031] The frictional torques of the other contact pairs are as follows: ; ; ; ; Among them, F a , where T is the axial preload, P is the tightening torque, and P is the thread pitch. Let λ be the helix angle of the helical pair, and λ be the equivalent friction angle of the helical pair. µ1 is the friction coefficient of the first contact pair, r1 is the equivalent radius of the first contact pair, β is half of the thread profile angle of the helical pair, µ2 is the friction coefficient of the second contact pair, r2 is the equivalent radius of the second contact pair, α2 is half of the inner cone angle of the flared guide tube, µ3 is the friction coefficient of the third contact pair, r3 is the equivalent radius of the third contact pair, α3 is half of the outer cone angle of the flared guide tube, µ4 is the friction coefficient of the fourth contact pair, and r4 is the equivalent radius of the fourth contact pair.

[0032] Therefore, the axial preload F can be obtained. a The relationship between the tightening torque T and the torque T is expressed as follows: ; Theoretically, the contact point between the flared conduit 1 and the flat nozzle 2 is static friction, and T3=0. However, due to the influence of manufacturing dimensional deviations and surface roughness of various components in the flared connection pipeline, the flat nozzle 2 may rotate. Therefore, T3 cannot be directly ignored, and T4 is affected by the friction coefficient between the contact pairs.

[0033] Based on the formula for tightening torque T, and considering the actual assembly situation, we can first reduce the friction coefficient at the contact points of the inner and outer surfaces of the flat nozzle 2 by increasing lubrication, thereby reducing the conversion of tightening torque T into axial preload F. a The loss; then, during the installation of the flared conduit, ground pre-assembly measures are added. Under the condition that there is no assembly deviation on the ground, the manufacturing error is analyzed by the shape of the sealing ring after installation. Then, the flat pipe nozzle 2 is rotated to adjust the contact position, redistribute the contact stress evenly, and eliminate the influence of the manufacturing error of each component of the flared connection pipeline on its sealing performance after installation.

[0034] In step S100, the visual inspection generally includes the surface quality inspection of the conduit body, flat nozzle, outer nut, and pipe joint. There should be no burrs, dents, scratches, cracks, rust, or other mechanical damage at each contact sealing surface.

[0035] In step S200, a clean degreased cotton ball is placed outside the open end of the pipe connector to be cleaned, and the other end of the pipe connector is connected to the air blower connector. The pipe connector is cleaned by blowing air for 8-10 seconds. If no metal shavings, adhesive particles and other contaminants appear on the degreased cotton ball, the pipe connector is considered to be cleaned. Otherwise, it should be cleaned again.

[0036] In step S300, the ground pre-assembly specifically includes the following steps: S310 Ground Connection Tightening: With the ground free, apply grease and use tools to tighten the flared guide tube; S320. Loosening Inspection: Loosen the connection and check the shape of the sealing ring between the flared conical surface of the tubing and the fitting, such as the width and continuity of the sealing ring. S330. Adjust according to the condition of the sealing ring: Determine whether the shape of the sealing ring meets the requirements. If it does, proceed to the next step. If it does not, rotate and adjust the position of the flat nozzle and optimize the tightening torque, then repeat steps S310 to S330. S340. After pre-assembly, wipe the marks made on the flared guide tube 1 and the flat nozzle 2, and mark the new alignment position, marking the assembly position between the flared guide tube and the flat nozzle.

[0037] In step S310, during the initial pre-installation of the pipeline (this step can be skipped during subsequent pre-installation tightening and leak detection), first rotate the flat pipe nozzle 2 360° around the central axis of the flared conduit 1 for inspection. If... Figure 6 As shown in Figure a; check for any tightness between the flared tube 1 and the flat nozzle 2. If necessary, proceed as follows: Figure 6 As indicated by mark b, tightness marks are made on the end of the flat nozzle 2 and the surface of the flared guide tube 1. During pre-assembly and tightening, the flat nozzle 2 must first be rotated around the central axis of the flared guide tube 1 and stopped in the non-tightness mark area, as shown in the mark b. Figure 6As shown in c.

[0038] Apply an appropriate amount of lubricating grease (such as 7903) to the threaded connection and the inner and outer surfaces of the flat tube nozzle 2. Be careful not to let any grease or oil enter the inside of the conduit.

[0039] In step S330, the shape of the sealing ring is analyzed to see if it meets the requirements. Figure 5 As shown in Figure a, if the sealing ring is continuous and has a uniform width, the width of the sealing ring... If the requirements are met, the sealing ring shape is deemed to meet the requirements. When the diameter of the flared conduit 1 is ≥ At 12mm, it is generally necessary to ensure ≥0.5mm, when the diameter of the flared catheter 1 is < At 12mm, it is generally necessary to ensure ≥1mm.

[0040] If the shape of the sealing ring does not meet the requirements, the position of the flat nozzle 2 needs to be rotated and adjusted, and the tightening torque optimized. Then, the tightening and sealing ring inspection operations are repeated until the requirements are met.

[0041] like Figure 5 Tables b, 5c, 5d, and 5e show several main types of non-compliant sealing ring shapes. The assembly adjustment and handling methods corresponding to different sealing ring shapes are as follows:

[0042] 1) such as Figure 5 b. The sealing ring has a uniform width but multiple breaks;

[0043] Reference Figure 6 b. At the marked break points on the flared guide tube 1 and the flat nozzle 2, avoid the break points and gradually rotate the flat nozzle 2 at a certain angle (the rotation angle is determined according to the distance between the break points, and gradually increases by a certain angle, such as 30°, 60°, 90°. After each rotation adjustment, it is necessary to retighten and check until it meets the requirements) and increase the tightening torque. Then perform steps S310 to S330 (the rotation check in step S310 is not required).

[0044] 2) such as Figure 5 c. The sealing ring has a uniform width but has one break point;

[0045] Reference Figure 6 b. At the marked break point on the flared tube 1 and flat nozzle 2, avoid the break point and gradually rotate and adjust the position of flat nozzle 2 at a certain angle and increase the tightening torque. Then perform steps S310 to S330 (no need to perform the rotation check in step S310 again).

[0046] 3) such as Figure 5 d, The sealing ring has a uniform width but two breakpoints;

[0047] Reference Figure 6 b. At the marked break point on the flared tube 1 and flat nozzle 2, avoid the break point, rotate the flat nozzle 2 at a 90° angle to adjust its position and increase the tightening torque, and then perform steps S310 to S330 (the rotation check in step S310 is not required).

[0048] 4) such as Figure 5 e. The sealing ring is continuous but its width is uneven;

[0049] Reference Figure 6 b. Mark the minimum width of the sealing ring on the flared guide tube 1 and the flat nozzle 2. At the corresponding position, rotate and adjust the flat nozzle 2 position by 180° (so that the minimum width and maximum width positions are interchanged), and increase the tightening torque as needed (e.g., If the requirements are met, there is no need to increase the tightening torque, such as If it does not meet the requirements, the tightening torque needs to be increased, and then proceed with steps S310 to S330 (no need to perform the rotation check in step S310 again).

[0050] In step S400, the pipeline laying sequence follows the principle of large to small, inside to outside, and bottom to top; apply an appropriate amount of lubricant (such as 7903) to the threaded connection and the inner and outer surfaces of the flat pipe nozzle 2, and be careful not to let any grease or oil enter the inside of the conduit;

[0051] The preliminary connection of pipelines and their fixing points refers to the preliminary connection and fixing of the connectors to be installed, but not the complete tightening of pipelines and fixing points such as clamps.

[0052] In step S500, when tightening, avoid forcibly assembling under stress, apply force smoothly, and the fixing points of pipe clamps and clamps should not be located in the R zone of the pipe connector to avoid damaging the pipe connector.

[0053] The installation should be coordinated according to the concept of a piping system (a piping system is a collection of pipes consisting of fixed assembly reference points and connecting conduits, fixing points, and conduit connections; assembly reference points can be fixed finished products, joints, structures, etc.). During coordination, minor adjustments can be made to the assembly state of the conduits, including reasonably distributing the connection stress at each connection end, adjusting the gap between the pipe connectors and the surrounding structure, and finally tightening the fixing screws and bolts at the conduit connections and fixing points. It should be noted that fixing points generally serve to limit and support the conduits; therefore, the final tightening of the conduit connections and the final tightening of the fixing point clamps and bolts must be coordinated and performed alternately.

[0054] The method for installing the flared conduit of the present invention will be further described below with reference to specific embodiments.

[0055] Example 1

[0056] A certain HB4-1 series flared connection pipe includes a flared conduit 1, a flat nozzle 2, an outer nut 3, and a pipe fitting 4, with a pipe diameter of [missing information]. 8mm. The specific steps for installing flared conduit pipes include:

[0057] S100. Pre-installation inspection: Remove the sealing and wrapping materials and inspect the appearance of the conduit. There should be no burrs, dents, scratches, cracks, rust and other mechanical damage at each contact sealing surface.

[0058] S200. Flushing the conduit: The inner wall of the conduit is flushed with clean nitrogen. Place clean degreased cotton on the open end of the conduit to be flushed, and connect the other end of the conduit to the air blowing connector. Flushing for 8-10 seconds. If no metal shavings, adhesive particles and other contaminants appear on the degreased cotton ball, the conduit is considered to be clean. Otherwise, it should be flushed again.

[0059] S300, Ground Pre-assembly: In a free state on the ground, tighten the conduit, then loosen it and analyze the shape of the conduit sealing ring to determine if it meets the requirements; this step specifically includes:

[0060] S310, Ground Connection Tightening: In the free state on the ground, first rotate the flat nozzle 2 360° around the central axis of the flared guide tube 1 to check for a tight spot between the flared guide tube 1 and the flat nozzle 2. When pre-assembling and tightening, first rotate the flat nozzle 2 around the central axis of the flared guide tube 1 and stop in the non-tight spot area. Apply an appropriate amount of lubricant 7903 to the threaded connection of the guide tube and the inner and outer surfaces of the flat nozzle 2, and then use tools to tighten the guide tube.

[0061] S320. Loosening Inspection: Loosen the pipe connection and check the shape of the sealing ring, such as its width and continuity.

[0062] S330, Analysis of sealing ring condition: The sealing ring width is uniform and ≈2mm (pipe diameter < 12mm, must be guaranteed ≥1mm), but there is one breakpoint, indicating that the first pre-assembly does not meet the requirements. It is necessary to rotate and adjust the position of the flat tube nozzle 2 and optimize the tightening torque; mark the breakpoint position, rotate the flat tube nozzle 2 counterclockwise by 30° (avoiding the breakpoint position) and increase the tightening torque, then repeat steps S310~S330, loosen and check again to find that the sealing ring shape meets the requirements.

[0063] S340, Pre-assembly complete. Wipe the old markings on the flared tube 1 and flat nozzle 2, and make new alignment markings.

[0064] S400, Laying and Connection: Lay the conduit to the specified position, apply an appropriate amount of lubricating grease 7903 to the threaded connection of the conduit and the inner and outer surfaces of the flat nozzle 2, and initially connect the conduit and its fixing points;

[0065] S500, Tightening and Fixing: Coordinate the installation according to the piping system concept, check and adjust the assembly status of the conduit, maintain the pre-assembled position of the flat nozzle 2, and perform the final tightening and fixing operation on the conduit.

[0066] S600, Safety Locking: Implement safety locking measures at the catheter connection points according to specifications, and wipe the markings on the flared catheter 1 and the flat nozzle 2.

[0067] S700 Assembly Status Inspection: Inspect the condition of the conduit after assembly, including the correctness of the connection, the clearance with the surroundings, the standardization of the safety device, and the surface quality of the conduit and accessories.

[0068] S800, Sealing Inspection: Verify the sealing of the pipeline, and detect and eliminate any leaks at the pipe connections.

[0069] Example 2

[0070] A certain HB4-1 series flared connection pipe includes a flared conduit 1, a flat nozzle 2, an outer nut 3, and a pipe fitting 4, with a pipe diameter of [missing information]. The installation method for 16mm flared conduit includes the following steps:

[0071] S300, Ground Pre-assembly: In the free state on the ground, analyze the shape of the conduit sealing ring, determine whether it meets the requirements, and perform ground pre-assembly and tightening operation on the pipeline.

[0072] S320. Loosening Inspection: Loosen the pipe connection and check the shape of the sealing ring, such as its width and continuity.

[0073] S330. Analysis of sealing ring condition: The sealing ring has a continuous shape but uneven width; the sealing ring width... 0.5~2mm (pipe diameter ≥ 12mm, must be guaranteed (≥0.5mm), after adjusting the position of the flat nozzle and tightening torque, mark the minimum width of the sealing ring. Position: Rotate the flat nozzle 2 at a 180° angle to adjust its position. No need to increase the tightening torque. Then proceed with steps S310 to S330. Loosen it again and check to find that the sealing ring shape meets the requirements.

[0074] S340, Pre-assembly complete. Wipe the old markings on the flared tube 1 and flat nozzle 2, and make new alignment markings.

[0075] S400, Laying and Connection: Lay the conduit to the specified position, apply an appropriate amount of lubricating grease 7903 to the threaded connection of the conduit and the inner and outer surfaces of the flat nozzle 2 (note that no grease or oil should enter the conduit), and initially connect the conduit and its fixing points.

[0076] S500, Tightening and Fixing: Coordinate the installation according to the piping system concept, check and adjust the assembly status of the conduit, maintain the pre-assembled position of the flat nozzle 2, and perform the final tightening and fixing operation on the conduit.

[0077] S600, Safety Locking: Implement safety locking measures at the catheter connection points according to specifications, and wipe the markings on the flared catheter 1 and the flat nozzle 2.

[0078] S700 Assembly Status Inspection: Inspect the condition of the conduit after assembly, including the correctness of the connection, the clearance with the surroundings, the standardization of the safety device, and the surface quality of the conduit and accessories.

[0079] S800, Sealing Inspection: Verify the sealing of the pipeline, and detect and eliminate any leaks at the pipe connections.

[0080] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., used to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of this invention is usually placed in during use. They are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0081] Furthermore, the use of terms such as "horizontal" and "vertical" in the description of this invention does not imply that the components are required to be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0082] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention in light of the specific circumstances.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for installing a flared conduit pipe, the pipe comprising a flared conduit, a flat nozzle, a sleeve nut and a pipe joint, the flat nozzle being sleeved on the flared conduit, the pipe joint and the flat nozzle being connected by the sleeve nut, the flared end of the flared conduit being pressed on the tapered surface interface of the pipe joint, a sealing ring being formed between the inner tapered surface of the flared end of the flared conduit and the outer tapered surface of the tapered surface interface; characterized in that, The method comprises the following steps: In the free state on the ground, grease is applied at the assembly position of the pipeline, the flared conduit is tightened, then loosened and analyzed for the sealing ring shape, the installation angle between the flared conduit and the flat nozzle in the pipeline and the tightening torque are adjusted according to the sealing ring shape until the sealing ring shape meets the requirements, and the assembly position between the flared conduit and the flat nozzle is marked on the flared conduit and the flat nozzle; The flared conduit is laid to the actual installation position, grease is applied and installation is performed.

2. The flared conduit run installation method of claim 1, wherein, The sealing ring shape is judged to determine whether the sealing ring shape meets the requirements, when the sealing ring shape does not meet the requirements, the flared conduit is rotated to adjust the installation angle between the flared conduit and the flat nozzle until the sealing ring shape meets the requirements.

3. The flared conduit run installation method of claim 2, wherein, When the sealing ring is continuous, the width is uniform and the sealing ring width meets the requirements, it is determined that the sealing ring shape meets the requirements.

4. The flared conduit run installation method of claim 3, wherein, When the sealing ring width is uniform but has multiple breakpoints, the flat nozzle is rotated to avoid the breakpoint position and the tightening torque is increased; the flared conduit is repeatedly tightened and the sealing ring shape is checked until the sealing ring shape meets the requirements.

5. The flared conduit run installation method of claim 3, wherein, When the sealing ring width is uniform but has one breakpoint, the flat nozzle is rotated to avoid the breakpoint position and the tightening torque is increased; the flared conduit is repeatedly tightened and the sealing ring shape is checked until the sealing ring shape meets the requirements.

6. The flared conduit run installation method of claim 3, wherein, When the sealing ring width is uniform but has two breakpoints, the flat nozzle is rotated by 90° and the tightening torque is increased; the flared conduit is repeatedly tightened and the sealing ring shape is checked until the sealing ring shape meets the requirements.

7. The flared conduit run installation method of claim 3, wherein, When the sealing ring is continuous but the width is not uniform, the position corresponding to the minimum width of the sealing ring is marked on the flared conduit and the flat nozzle, the flat nozzle is rotated by 180° and the tightening torque is adjusted according to the minimum width of the sealing ring; the flared conduit is repeatedly tightened and the sealing ring shape is checked until the sealing ring shape meets the requirements.

8. The flared conduit run installation method according to claim 1, wherein, When the pipeline is pre-assembled for the first time, the flat nozzle is rotated around the center axis of the flared conduit to check whether there is a tight point between the flared conduit and the flat nozzle, and the position of the tight point is assembled; when the pipeline is assembled and tightened on the ground, the installation angle between the flat nozzle and the flared conduit is adjusted to stagger the position of the tight point.

9. The flared conduit run installation method according to any of claims 1-7, wherein, The relationship between the assembly axial pretightening force and the tightening torque is analyzed and established; The tightening torque is the sum of the friction torques of the first contact pair, the second contact pair, the third contact pair, the fourth contact pair, the fifth contact pair and the sixth contact pair; the first contact pair is the contact pair of the screw pair between the sleeve nut and the pipe joint; the second contact pair is the contact pair formed by the inner taper surface of the flared conduit and the corresponding taper surface of the pipe joint; the third contact pair is the contact pair formed by the outer taper surface of the flared conduit and the inner taper surface of the head of the flat nozzle; the fourth contact pair is the contact pair formed by the side circular surface of the flat nozzle and the sleeve nut, the fifth contact pair is the contact pair formed by the circular hole inner surface at the tail end of the sleeve nut and the cylindrical outer surface of the flat nozzle; and the sixth contact pair is the contact pair formed by the straight pipe portion of the flared conduit and the cylindrical inner surface of the flat nozzle.

10. The flared conduit run installation method of claim 9, wherein, The relationship between the assembly axial pretightening force and the tightening torque is represented as: T=T1+T2+T3+T4+T5+T6; Wherein, T1, T2, T3, T4, T5, T6 are friction torque of the first contact pair, the second contact pair, the third contact pair, the fourth contact pair, the fifth contact pair, the sixth contact pair respectively; and T2=0, T5=0, T6=0; Get: ； where F a is the axial pretension, T is the tightening torque, P is the thread pitch, m1 is the friction coefficient of the first contact pair, r1 is the equivalent radius of the first contact pair, b is the 1 / 2 of the thread angle of the screw pair, m3 is the friction coefficient of the third contact pair, r3 is the equivalent radius of the third contact pair, a3 is the 1 / 2 of the outer cone angle of the flared conduit, m4 is the friction coefficient of the fourth contact pair, and r4 is the equivalent radius of the fourth contact pair.

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