Welding method and welding device for long-distance pipeline, processor and storage medium

Abstract

The embodiment of the present invention provides a welding method and welding device, processor and storage medium for long-distance pipelines, which belongs to the technical field of pipeline welding. The welding method for long-distance pipelines includes: obtaining a preset delivery volume of the long-distance pipeline; determining the outer diameter of the long-distance pipeline according to the preset delivery volume; determining the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the outer diameter of the pipe and the preset delivery volume, wherein the curved pipe wall thickness is greater than the straight pipe wall thickness; correcting the straight pipe wall thickness to obtain a corrected straight pipe wall thickness, wherein the corrected straight pipe wall thickness is equal to the curved pipe wall thickness; selecting a straight pipe and a curved pipe according to the corrected straight pipe wall thickness and the outer diameter of the pipeline, the curved pipe wall thickness and the outer diameter of the pipeline; welding the selected straight pipe and curved pipe. The technical solution of the embodiment of the present invention can reduce the hidden dangers of weld failure.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline welding, and in particular to a welding method and welding device, a processor and a storage medium for long-distance pipelines. Background Art

[0002] In the prior art, when straight pipes and curved pipes in long-distance pipelines are butt-welded, the root weld often forms a misaligned edge inside the pipeline. The existence of the misaligned edge easily causes stress concentration in the weld, that is, uneven stress distribution, which may lead to the hidden danger of weld failure during subsequent use. Therefore, the existing welding methods for long-distance pipelines have the hidden danger of weld failure. Summary of the invention

[0003] The purpose of the embodiments of the present invention is to provide a welding method for a long-distance pipeline, a welding device for a long-distance pipeline, a processor, a long-distance pipeline and a storage medium to solve the problem of weld failure hidden danger in the prior art.

[0004] In order to achieve the above-mentioned object, a first aspect of an embodiment of the present invention provides a welding method for a long-distance pipeline, wherein the long-distance pipeline includes a straight pipe and a curved pipe, and the welding method includes:

[0005] Obtain the preset delivery volume of long-distance pipelines;

[0006] Determine the outer diameter of the long-distance pipeline according to the preset delivery volume;

[0007] Determine the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the outer diameter of the pipeline and the preset conveying volume, wherein the curved pipe wall thickness is greater than the straight pipe wall thickness;

[0008] Correcting the wall thickness of the straight pipe to obtain a corrected wall thickness of the straight pipe, wherein the corrected wall thickness of the straight pipe is equal to the wall thickness of the bent pipe;

[0009] Select straight pipes and bent pipes according to the corrected straight pipe wall thickness and pipe outer diameter, bent pipe wall thickness and pipe outer diameter respectively;

[0010] The selected straight pipes and bent pipes are welded.

[0011] In an embodiment of the present invention, determining the outer diameter of the long-distance pipeline according to a preset delivery volume includes: determining the outer diameter of the long-distance pipeline according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the outer diameter of the pipeline.

[0012] In an embodiment of the present invention, the straight pipe wall thickness of a straight pipe and the curved pipe wall thickness of a curved pipe are determined according to the outer diameter of the pipeline and a preset delivery volume, including: obtaining the regional level of the area where the long-distance pipeline is located, wherein the regional level is obtained according to the population density; determining the straight pipe strength coefficient corresponding to the regional level according to the regional level; determining the straight pipe pressure of the straight pipe according to the preset delivery volume; determining the minimum yield strength of the straight pipe and the curvature radius of the curved pipe according to the outer diameter of the pipeline; determining the straight pipe wall thickness according to the straight pipe pressure, the outer diameter of the pipeline, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe; determining the curved pipe wall thickness according to the straight pipe wall thickness, the curvature radius and the outer diameter of the pipeline.

[0013] In the embodiment of the present invention, the preset parameters of the straight pipe include the weld coefficient of the straight pipe and the temperature reduction coefficient of the straight pipe; the wall thickness of the straight pipe is determined according to the straight pipe pressure, the outer diameter of the pipe, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe, including determining the wall thickness of the straight pipe according to formula (1):

[0014]

[0015] Among them, δ is the wall thickness of the straight pipe, P is the straight pipe pressure, D is the outer diameter of the pipe, σ S is the minimum yield strength, is the weld coefficient, F is the straight pipe strength coefficient, and t is the temperature reduction coefficient.

[0016] In an embodiment of the present invention, the wall thickness of the bent pipe is determined according to the wall thickness of the straight pipe, the radius of curvature and the outer diameter of the pipe, including determining the wall thickness of the bent pipe according to formula (2):

[0017] δ b =δ×m=δ×[(4R-d) / (4R-2d)] Formula (2)

[0018] Among them, δ b is the wall thickness of the bent pipe, δ is the wall thickness of the straight pipe, m is the wall thickness increase coefficient of the bent pipe, R is the radius of curvature, and d is the outer diameter of the pipe.

[0019] In an embodiment of the present invention, determining the straight pipe strength coefficient corresponding to the regional level according to the regional level includes: determining the straight pipe strength coefficient corresponding to the regional level according to the regional level based on a pre-stored correspondence between the regional level and the straight pipe strength coefficient.

[0020] In an embodiment of the present invention, determining the straight pipe pressure of the straight pipe according to a preset delivery volume includes: determining the straight pipe pressure of the straight pipe according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the pressure.

[0021] In an embodiment of the present invention, the minimum yield strength of a straight pipe and the curvature radius of a bent pipe are determined according to the outer diameter of the pipe, including: determining the minimum yield strength of the straight pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the minimum yield strength; determining the curvature radius of the bent pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the curvature radius.

[0022] In an embodiment of the present invention, the selected straight pipe and the bent pipe are welded, including: welding the selected straight pipe and the bent pipe by root welding, filling welding and cap welding in sequence.

[0023] In the embodiment of the present invention, the single filling thickness corresponding to the filling welding does not exceed 2.5 mm.

[0024] In the embodiment of the present invention, the selected straight pipe and bent pipe are welded using a double V-shaped composite groove.

[0025] In the embodiment of the present invention, the straight tube strength coefficient ranges from 0.4 to 0.8.

[0026] A second aspect of an embodiment of the present invention provides a processor configured to execute the above-mentioned welding method for a long-distance pipeline.

[0027] A third aspect of an embodiment of the present invention provides a welding device for a long-distance pipeline, comprising: a processor according to the above.

[0028] A fourth aspect of an embodiment of the present invention provides a long-distance pipeline, which includes a straight pipe and a curved pipe. The long-distance pipeline is welded according to the above-mentioned welding method for the long-distance pipeline.

[0029] A fifth aspect of an embodiment of the present invention provides a machine-readable storage medium, on which instructions are stored. When the instructions are executed by a processor, the processor executes the above-mentioned welding method for long-distance pipelines.

[0030] The above technical solution obtains the preset delivery volume of the long-distance pipeline, determines the outer diameter of the long-distance pipeline according to the preset delivery volume, and then determines the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the outer diameter and the preset delivery volume, thereby correcting the straight pipe wall thickness to obtain the corrected straight pipe wall thickness, and the corrected straight pipe wall thickness is equal to the curved pipe wall thickness, and then selects the straight pipe and the curved pipe respectively according to the corrected straight pipe wall thickness and the outer diameter of the pipeline, the curved pipe wall thickness and the outer diameter of the pipeline, and welds the selected straight pipe and curved pipe. The above solution increases the wall thickness of the straight pipe to the same wall thickness as the curved pipe, which can avoid the problem of weld stress concentration caused by misalignment of the butt welds of unequal wall thicknesses inside the pipeline in the long-distance pipeline, improves the stability of the pipeline welding quality, greatly reduces the hidden dangers of weld failure, and ensures the safety of the long-distance pipeline.

[0031] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0033] Figure 1 The schematic diagram shows a flow chart of a welding method for a long-distance pipeline in one embodiment of the present invention;

[0034] FIG2( a ) schematically shows a schematic structural diagram of a straight pipe and a curved pipe in the prior art in one embodiment of the present invention;

[0035] FIG. 2( b ) schematically shows a schematic diagram of the butt welding of the straight pipe and the bent pipe in FIG. 2( a ) in one embodiment of the present invention;

[0036] FIG3( a ) schematically shows a schematic diagram of the structure of a straight pipe and a curved pipe in one embodiment of the present invention;

[0037] FIG. 3( b ) schematically shows a schematic diagram of the butt welding of the straight pipe and the bent pipe in FIG. 3( a ) in one embodiment of the present invention.

[0038] Description of Reference Numerals

[0039] 1 Straight pipe 2 Bend pipe

[0040] 3 Welding seams DETAILED DESCRIPTION

[0041] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0042] Figure 1 The schematic diagram of the process flow of the welding method for long-distance pipeline in one embodiment of the present invention is shown schematically. Figure 1 As shown, in an embodiment of the present invention, a welding method for a long-distance pipeline is provided. The long-distance pipeline includes a straight pipe and a curved pipe. The welding method is applied to a processor as an example for description. Specifically, the following steps may be included:

[0043] Step S102, obtaining a preset transport volume of the long-distance pipeline.

[0044] Step S104, determining the outer diameter of the long-distance pipeline according to the preset delivery volume.

[0045] Step S106, determining the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the outer diameter of the pipeline and the preset conveying volume, wherein the curved pipe wall thickness is greater than the straight pipe wall thickness.

[0046] Step S108, correcting the straight pipe wall thickness to obtain a corrected straight pipe wall thickness, wherein the corrected straight pipe wall thickness is equal to the bent pipe wall thickness.

[0047] Step S110, selecting a straight pipe and a curved pipe according to the corrected straight pipe wall thickness and pipe outer diameter, curved pipe wall thickness and pipe outer diameter.

[0048] Step S112, welding the selected straight pipe and bent pipe.

[0049] It can be understood that the long-distance pipeline can be used to transport natural gas, oil and other media, and the preset delivery volume is the medium delivery volume of the pre-set long-distance pipeline within a preset time range (for example, one year), such as the gas delivery volume.

[0050] Specifically, the processor can obtain the preset delivery volume of the long-distance pipeline input by the user or pre-set and stored, and determine the outer diameter of the pipeline of the long-distance pipeline according to the preset delivery volume. For example, the outer diameter of the pipeline of the long-distance pipeline can be determined according to the preset delivery volume based on the corresponding relationship between the delivery volume and the outer diameter of the pipeline, or the preset delivery volume can be used as an input based on a pre-stored algorithm that characterizes the relationship between the delivery volume and the outer diameter of the pipeline to obtain an output result, that is, the outer diameter of the pipeline of the long-distance pipeline. Further, the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe are determined according to the outer diameter of the pipeline and the preset delivery volume. For example, the straight pipe wall thickness of the straight pipe can be determined according to the corresponding relationship among the outer diameter of the pipeline, the preset delivery volume and the straight pipe wall thickness, and the curved pipe wall thickness of the curved pipe can be determined according to the corresponding relationship among the outer diameter of the pipeline, the preset delivery volume and the curved pipe wall thickness. The straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe can also be determined according to the corresponding relationship among the outer diameter of the pipeline, the preset delivery volume, the straight pipe wall thickness and the curved pipe wall thickness, wherein the curved pipe wall thickness is greater than the straight pipe wall thickness. At this time, the processor can correct the wall thickness of the straight pipe, that is, increase the wall thickness of the straight pipe so that the corrected wall thickness of the straight pipe is equal to the wall thickness of the bent pipe. Thus, the processor can select the type of straight pipe according to the corrected wall thickness of the straight pipe and the outer diameter of the pipe, and select the type of bent pipe according to the wall thickness of the bent pipe and the outer diameter of the pipe, and then the processor can control a specific actuator (such as a welding machine or a welding robot) to weld the selected straight pipe and bent pipe to obtain a long-distance pipeline.

[0051] The above-mentioned welding method for long-distance pipelines obtains the preset delivery volume of the long-distance pipeline, and determines the outer diameter of the long-distance pipeline according to the preset delivery volume, and then determines the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the outer diameter of the pipe and the preset delivery volume, thereby correcting the straight pipe wall thickness to obtain the corrected straight pipe wall thickness, and the corrected straight pipe wall thickness is equal to the curved pipe wall thickness, and then selects the straight pipe and the curved pipe respectively according to the corrected straight pipe wall thickness and the outer diameter of the pipeline, the curved pipe wall thickness and the outer diameter of the pipeline, and welds the selected straight pipe and curved pipe. The above-mentioned scheme increases the wall thickness of the straight pipe to the same wall thickness as the curved pipe, which can avoid the problem of weld stress concentration caused by misalignment of the butt welds of unequal wall thicknesses inside the pipeline in the long-distance pipeline, improves the stability of the pipeline welding quality, greatly reduces the hidden dangers of weld failure, and ensures the safety of the long-distance pipeline.

[0052] In one embodiment, determining the outer diameter of the long-distance pipeline according to a preset delivery volume includes: determining the outer diameter of the long-distance pipeline according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the outer diameter of the pipeline.

[0053] It can be understood that the processor can pre-store the corresponding relationship between the pipeline delivery volume and the pipeline outer diameter, so as to determine the pipeline outer diameter of the long-distance pipeline according to the preset delivery volume.

[0054] In one embodiment, the straight pipe wall thickness of a straight pipe and the curved pipe wall thickness of a curved pipe are determined according to the outer diameter of the pipeline and a preset delivery volume, including: obtaining the regional level of the area where the long-distance pipeline is located, wherein the regional level is obtained according to the population density; determining the straight pipe strength coefficient corresponding to the regional level according to the regional level; determining the straight pipe pressure of the straight pipe according to the preset delivery volume; determining the minimum yield strength of the straight pipe and the curvature radius of the curved pipe according to the outer diameter of the pipeline; determining the straight pipe wall thickness according to the straight pipe pressure, the outer diameter of the pipeline, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe; determining the curved pipe wall thickness according to the straight pipe wall thickness, the curvature radius and the outer diameter of the pipeline.

[0055] It can be understood that a plurality of different regional levels can be obtained according to the size of population density, and the straight pipe strength coefficient is the strength coefficient of the straight pipe, which is related to the regional level. The preset parameters of the straight pipe are the parameters of the straight pipe set in advance, such as the temperature reduction coefficient of the straight pipe.

[0056] Specifically, the processor can obtain the regional level of the region where the long-distance pipeline is located, which is input by the user, so as to determine the straight pipe strength coefficient corresponding to the regional level according to the regional level, and determine the straight pipe pressure of the straight pipe according to the preset delivery volume. For example, according to the algorithm pre-stored to characterize the relationship between the regional level and the straight pipe strength coefficient, the regional level can be used as an input to obtain the output result, i.e., the straight pipe strength coefficient. According to the algorithm pre-stored to characterize the relationship between the delivery volume and the pressure, the preset delivery volume can be used as an input to obtain the output result, i.e., the straight pipe pressure of the straight pipe. Then, the processor can determine the minimum yield strength of the straight pipe and the curvature radius of the bend according to the outer diameter of the pipeline. For example, according to the corresponding relationship between the outer diameter of the pipeline and the steel grade, the steel grade corresponding to the outer diameter of the pipeline can be determined, and then the minimum yield strength of the straight pipe can be determined according to the steel grade, or, based on the algorithm pre-stored to characterize the outer diameter of the pipeline and the curvature radius, the curvature radius of the bend can be determined according to the outer diameter of the pipeline. Thus, the wall thickness of the straight pipe is determined according to the straight pipe pressure, the outer diameter of the pipe, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe. For example, the wall thickness of the straight pipe can be determined by a pre-trained algorithm, which may include parameters such as the straight pipe pressure, the outer diameter of the pipe, the minimum yield strength, the straight pipe strength coefficient, the preset parameters of the straight pipe and the straight pipe wall thickness. Then, the wall thickness of the bent pipe is determined according to the straight pipe wall thickness, the radius of curvature and the outer diameter of the pipe. For example, the wall thickness of the bent pipe can be determined by a pre-determined algorithm including the straight pipe wall thickness, the radius of curvature, the outer diameter of the pipe and the wall thickness of the bent pipe.

[0057] In one embodiment, the preset parameters of the straight pipe may include the weld coefficient of the straight pipe and the temperature reduction coefficient of the straight pipe; determining the wall thickness of the straight pipe according to the straight pipe pressure, the outer diameter of the pipe, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe may include determining the wall thickness of the straight pipe according to formula (1):

[0058]

[0059] Among them, δ is the wall thickness of the straight pipe, P is the straight pipe pressure, D is the outer diameter of the pipe, σ S is the minimum yield strength, is the weld coefficient, F is the straight pipe strength coefficient, and t is the temperature reduction coefficient.

[0060] In the embodiment of the present invention, the above formula (1) takes into account multiple parameters of the straight pipe. By determining the wall thickness of the straight pipe using the above formula (1), the accuracy of the wall thickness of the straight pipe can be improved.

[0061] In one embodiment, determining the wall thickness of the curved pipe according to the wall thickness of the straight pipe, the radius of curvature, and the outer diameter of the pipe may include determining the wall thickness of the curved pipe according to formula (2):

[0062] δ b =δ×m=δ×[(4R-d) / (4R-2d)] Formula (2)

[0063] Among them, δ b is the wall thickness of the bent pipe, δ is the wall thickness of the straight pipe, m is the wall thickness increase coefficient of the bent pipe, R is the radius of curvature, and d is the outer diameter of the pipe.

[0064] In the embodiment of the present invention, the wall thickness of the bent pipe is determined by the above formula (2), so that the accuracy of the wall thickness of the bent pipe can be improved.

[0065] In one embodiment, determining the straight pipe strength coefficient corresponding to the regional level according to the regional level includes: determining the straight pipe strength coefficient corresponding to the regional level according to the regional level based on a pre-stored correspondence between the regional level and the straight pipe strength coefficient.

[0066] In one embodiment, determining the straight pipe pressure of the straight pipe according to a preset delivery volume includes: determining the straight pipe pressure of the straight pipe according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the pressure.

[0067] In one embodiment, the minimum yield strength of a straight pipe and the curvature radius of a bent pipe are determined according to the outer diameter of the pipe, including: determining the minimum yield strength of the straight pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the minimum yield strength; determining the curvature radius of the bent pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the curvature radius.

[0068] In one embodiment, welding the selected straight pipe and the bent pipe includes: welding the selected straight pipe and the bent pipe in sequence by means of root welding, filling welding and cap welding.

[0069] It can be understood that the welding process of the bent pipe and the straight pipe may include root welding, filling welding and cap welding, and the root welding, filling welding and cap welding are performed in sequence.

[0070] In one embodiment, the single filling thickness corresponding to the filling weld does not exceed 2.5 mm.

[0071] It is understood that the single filling thickness during filling welding does not exceed 2.5mm. Root welding (including hot welding) completes the welding of the blunt edge, and then filling welding is performed, and the thickness of each filling does not exceed 2.5mm, and finally cap welding is performed.

[0072] In one embodiment, the selected straight pipe and bent pipe are welded using a double V-shaped composite groove.

[0073] In one embodiment, the straight tube strength coefficient ranges from 0.4 to 0.8.

[0074] It can be understood that the straight pipe strength coefficient in this range can improve the transportation safety of long-distance pipelines.

[0075] It can be understood that the range of the straight pipe strength coefficient may include 0.4 to 0.8, and the regional level may include Class I, Class II, Class II, Class III or Class IV according to population density. Among them, the design coefficient of Class I area may be 0.8, the design coefficient of Class I area may be 0.72, the design coefficient of Class II area may be 0.6, the design coefficient of Class III area may be 0.5, and the design coefficient of Class IV area may be 0.4.

[0076] In one embodiment, the long-distance pipeline may be the entire mountain long-distance pipeline or a local area of ​​the mountain long-distance pipeline, and the length is usually not more than 50 km. The welding method for the long-distance pipeline can be applied to mountainous areas with complex terrain (generally the slope is usually above 15°), 3 to 5 ditches / km, and 3 to 5 rural roads / km.

[0077] In an embodiment of the present invention, the welding method for long-distance pipelines can be used for pipeline welding construction in mountainous areas with large terrain undulations, more than 60% of the area with a slope of more than 15°, and complex construction conditions (for example, 3 to 5 ditches / km, 3 to 5 rural roads / km).

[0078] In the prior art, as shown in FIG. 2(a) and FIG. 2(b), the straight pipe and the curved pipe have the same outer diameter and different wall thickness. In an embodiment of the present invention, as shown in FIG. 3(a) and FIG. 3(b), the straight pipe and the curved pipe have the same outer diameter and wall thickness. The wall thickness of the straight pipe (e.g., straight steel pipe) and the curved pipe (e.g., hot-bent curved pipe) constituting the long-distance pipeline can be determined first. As shown in FIG. 2(a) and FIG. 2(b), under the same design coefficient (i.e., the straight pipe strength coefficient), the wall thickness of the curved pipe 2 is greater than the wall thickness of the straight pipe 1 and the inner diameter of the curved pipe 2 is smaller than the inner diameter of the straight pipe 1, resulting in problems such as misalignment and stress concentration inside the pipeline after the curved pipe 2 is welded to the straight pipe 1. The misalignment is mainly formed near the weld 3. As shown in FIG. 3(a) and FIG. 3(b), the wall thickness of the straight pipe 1 is increased to the same as that of the curved pipe 2, the outer diameter remains unchanged, and the curved pipe 2 and the straight pipe 1 are welded, which can reduce or even avoid the formation of misalignment and reduce the probability of weld failure.

[0079] In this exemplary embodiment, the welding method for long-distance pipelines can achieve a one-time pass rate of more than 95%, and the misalignment of the welding is within 2 mm.

[0080] The welding method for a long-distance pipeline provided by an embodiment of the present invention is described below in conjunction with another specific embodiment.

[0081] Under the same design coefficient (i.e. straight pipe strength coefficient), the design principle is to increase the wall thickness of general line pipes to the same level as the wall thickness of the hot-bent mother pipe under the design coefficient.

[0082] Take a long-distance pipeline project as an example. The total length of the project is 43.6 km. The design delivery pressure of the project is 10.0 MPa. The design outer diameter of the straight pipe section and the hot-bending pipe section is 1016 mm. The straight pipe section is made of X70 steel. The calculated wall thickness of the pipe for the general section of the line is 17.46 mm, and the rounded wall thickness is 17.5 mm. The thinning rate of the hot-bending pipe is 0.91. The calculated wall thickness of the hot-bending pipe is 19.18 mm, and the rounded wall thickness of the hot-bending pipe is 19.2 mm. The equal wall thickness design principle is adopted to increase the wall thickness of the pipe for the general section of the line from 43.6 mm in the whole line to 19.2 mm, the same as the wall thickness of the hot-bending pipe.

[0083] According to the long-distance pipeline design principles, the corresponding straight pipe strength coefficient is determined to be 0.6 when the regional grade is level 2, and the wall thickness and inner diameter of the straight steel pipe section and the hot-bent pipe section of the project are calculated respectively. It can be understood that the long-distance pipeline design principles are the pre-set long-distance pipeline design principles, and the long-distance pipeline design principles can be the corresponding national standards, specifically, for example, the gas pipeline engineering design specification (GB 50251-2015), etc.

[0084] Among them, the wall thickness of the straight steel pipe is related to the design pressure, the outer diameter of the straight steel pipe, the strength grade of the straight steel pipe, the strength design coefficient and the temperature reduction coefficient. The wall thickness of the straight steel pipe can be calculated by formula (1):

[0085]

[0086] Where, δ is the calculated wall thickness of the straight steel pipe, mm; P is the design pressure, which can be 10.0MPa; D is the outer diameter of the straight steel pipe, which can be 1016mm; σ S is the minimum yield strength of the straight steel pipe, which can be taken as 485MPa; is the straight steel pipe weld coefficient, which can be selected as 1.0; F is the strength design coefficient (i.e. the straight pipe strength coefficient), which can be selected as 0.6; t is the temperature reduction coefficient, which can be selected as 1.0. According to formula (1), the calculated wall thickness δ of the straight steel pipe is 17.46 mm, which is rounded to 17.5 mm, and the inner diameter is 981 mm.

[0087] Among them, the wall thickness of the hot-bent pipe can be calculated by formula (2):

[0088] δ b =δ×m=δ×[(4R-d) / (4R-2d)] Formula (2)

[0089] In the formula, δ bis the calculated wall thickness of the hot-bent pipe, mm; δ is the calculated wall thickness of the straight steel pipe section connected by the hot-bent pipe, which can be 1016mm; m is the wall thickness increase coefficient of the hot-bent pipe; R is the curvature radius of the hot-bent pipe, which can be 6D, D is the outer diameter of the straight steel pipe; d is the outer diameter of the hot-bent pipe, which can be 1016mm. The wall thickness of the hot-bent pipe is 19.18mm, rounded to 19.2mm, and the inner diameter is 979.3mm.

[0090] In order to avoid misalignment at the root of the connecting weld between the straight steel pipe section and the hot-bent pipe section due to unequal inner diameters, this project adopts the segmented equal wall thickness design principle under the same design coefficient, and increases the wall thickness of the general line pipe to the same design principle as the wall thickness of the hot-bent pipe mother pipe under the design coefficient. The equal wall thickness design principle can avoid the existence of unequal wall thickness welds in long-distance pipelines. By increasing the wall thickness of the straight steel pipe section from 17.5mm to 19.2mm, the problem of internal misalignment of the pipeline can be avoided after welding, which greatly reduces the number of 800 welding joints (about 400 elbows) of unequal wall thickness between the straight steel pipe section and the hot-bent pipe section, greatly reduces the welding problems such as misalignment and stress concentration caused by wall thickness difference during welding, and greatly ensures the inherent safety of the pipeline.

[0091] An embodiment of the present invention provides a processor configured to execute the welding method for a long-distance pipeline according to the above embodiment.

[0092] An embodiment of the present invention provides a welding device for a long-distance pipeline, comprising: a processor according to the above embodiment.

[0093] An embodiment of the present invention provides a long-distance pipeline, which includes a straight pipe and a curved pipe. The long-distance pipeline is welded according to the welding method for the long-distance pipeline in the above embodiment.

[0094] An embodiment of the present invention provides a machine-readable storage medium, on which instructions are stored. When the instructions are executed by a processor, the processor executes the welding method for a long-distance pipeline according to the above-mentioned embodiment.

[0095] In summary, the beneficial effects of the embodiments of the present invention may include:

[0096] (1) The equal wall thickness design principle mentioned in the welding method for long-distance pipelines provided in the embodiment of the present invention can avoid problems such as misalignment and stress concentration at the weld root of unequal wall thickness welds in long-distance pipelines, which may cause unstable pipeline welding quality and reduce the hidden danger of weld failure.

[0097] (2) The technical solution of the embodiment of the present invention can reduce about 400 heat treatments, i.e., 800 root weld misalignment problems of unequal wall thickness butt welds, thereby avoiding the misalignment and stress concentration problems of unequal wall thickness butt welds, and greatly ensuring the inherent safety of the pipeline.

[0098] Although the present invention has been described above by combining with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope defined in the claims.

Claims

1. A welding method for long-distance pipelines, characterized in that: The long-distance pipeline includes a straight pipe and a curved pipe, and the welding method includes: Obtain the preset delivery volume of long-distance pipelines; Determining the outer diameter of the long-distance pipeline according to the preset delivery volume; Determine the straight pipe wall thickness of the straight pipe and the bent pipe wall thickness of the bent pipe according to the outer diameter of the pipeline and the preset delivery volume, wherein the bent pipe wall thickness is greater than the straight pipe wall thickness; Correcting the straight pipe wall thickness to obtain a corrected straight pipe wall thickness, wherein the corrected straight pipe wall thickness is equal to the curved pipe wall thickness; Select the straight pipe and the bent pipe respectively according to the corrected straight pipe wall thickness and the pipe outer diameter, the bent pipe wall thickness and the pipe outer diameter; Welding the selected straight pipe and the bent pipe; Wherein, determining the outer diameter of the long-distance pipeline according to the preset delivery volume comprises: determining the outer diameter of the long-distance pipeline according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the outer diameter of the pipeline; The step of determining the straight pipe wall thickness of the straight pipe and the curved pipe wall thickness of the curved pipe according to the pipeline outer diameter and the preset delivery volume comprises: Obtaining a regional level of the region where the long-distance pipeline is located, wherein the regional level is obtained based on population density; Determine the straight pipe strength coefficient corresponding to the regional level according to the regional level; Determining the straight pipe pressure of the straight pipe according to the preset delivery volume; Determining the minimum yield strength of the straight pipe and the curvature radius of the curved pipe according to the outer diameter of the pipe; Determining the straight pipe wall thickness according to the straight pipe pressure, the pipe outer diameter, the minimum yield strength, the straight pipe strength coefficient and preset parameters of the straight pipe; Determining the wall thickness of the curved pipe according to the wall thickness of the straight pipe, the radius of curvature and the outer diameter of the pipe; The determining, according to the regional level, the straight pipe strength coefficient corresponding to the regional level comprises: determining, according to the regional level, the straight pipe strength coefficient corresponding to the regional level based on a pre-stored correspondence between the regional level and the straight pipe strength coefficient; Determining the straight pipe pressure of the straight pipe according to the preset delivery volume comprises: determining the straight pipe pressure of the straight pipe according to the preset delivery volume based on a pre-stored correspondence between the delivery volume and the pressure; Determining the minimum yield strength of the straight pipe and the curvature radius of the curved pipe according to the outer diameter of the pipe comprises: determining the minimum yield strength of the straight pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the minimum yield strength; determining the curvature radius of the curved pipe according to the outer diameter of the pipe based on a pre-stored correspondence between the outer diameter of the pipe and the curvature radius; The preset parameters of the straight pipe include the weld coefficient of the straight pipe and the temperature reduction coefficient of the straight pipe; the straight pipe wall thickness is determined according to the straight pipe pressure, the pipe outer diameter, the minimum yield strength, the straight pipe strength coefficient and the preset parameters of the straight pipe, including determining the straight pipe wall thickness according to formula (1): Wherein, δ is the wall thickness of the straight pipe, P is the straight pipe pressure, D is the outer diameter of the pipe, σ S is the minimum yield strength, is the weld coefficient, F is the straight pipe strength coefficient, and t is the temperature reduction coefficient; Determining the wall thickness of the curved pipe according to the wall thickness of the straight pipe, the radius of curvature and the outer diameter of the pipe includes determining the wall thickness of the curved pipe according to formula (2): δ b =δ×m=δ×[(4R-d) / (4R-2d)] Formula (2) Among them, δ b is the wall thickness of the bent pipe, δ is the wall thickness of the straight pipe, m is the wall thickness increase coefficient of the bent pipe, R is the radius of curvature, and d is the outer diameter of the pipe.

2. The welding method according to claim 1, characterized in that: The step of welding the selected straight pipe and the bent pipe comprises: The selected straight pipe and the bent pipe are welded in sequence by means of root welding, filling welding and cap welding.

3. The welding method according to claim 2, characterized in that: The single filling thickness corresponding to the filling welding does not exceed 2.5 mm.

4. The welding method according to claim 1, characterized in that: The selected straight pipe and the bent pipe are welded using a double V-shaped composite groove.

5. The welding method according to claim 1, characterized in that: The straight tube strength coefficient ranges from 0.4 to 0.

8.

6. A processor, characterized in that: The device is configured to perform the welding method for a long-distance pipeline according to any one of claims 1 to 5.

7. A welding device for long-distance pipelines, characterized in that: include: A processor according to claim 6.

8. A long-distance pipeline, characterized in that: The long-distance pipeline comprises a straight pipe and a curved pipe, and the long-distance pipeline is welded according to the welding method for long-distance pipeline according to any one of claims 1 to 5.

9. A machine-readable storage medium having instructions stored thereon, characterized in that: When the instruction is executed by a processor, the processor executes the welding method for a long-distance pipeline according to any one of claims 1 to 5.

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