CN112570998B - Manufacturing process method of air cooling pipeline of thermal generator set - Google Patents
Manufacturing process method of air cooling pipeline of thermal generator set Download PDFInfo
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- CN112570998B CN112570998B CN202011468630.3A CN202011468630A CN112570998B CN 112570998 B CN112570998 B CN 112570998B CN 202011468630 A CN202011468630 A CN 202011468630A CN 112570998 B CN112570998 B CN 112570998B
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- 238000000034 method Methods 0.000 title claims abstract description 72
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 47
- 238000001816 cooling Methods 0.000 title claims abstract description 20
- 238000003466 welding Methods 0.000 claims abstract description 66
- 238000005096 rolling process Methods 0.000 claims abstract description 41
- 238000007689 inspection Methods 0.000 claims abstract description 40
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 25
- 239000010959 steel Substances 0.000 claims abstract description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000010276 construction Methods 0.000 claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims abstract description 12
- 229910052751 metal Inorganic materials 0.000 claims abstract description 12
- 229910052742 iron Inorganic materials 0.000 claims abstract description 11
- 238000005520 cutting process Methods 0.000 claims abstract description 9
- 238000001514 detection method Methods 0.000 claims abstract description 7
- 238000005498 polishing Methods 0.000 claims abstract description 5
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- 230000008569 process Effects 0.000 claims description 40
- 238000012937 correction Methods 0.000 claims description 23
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- 238000005516 engineering process Methods 0.000 description 3
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- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
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- 238000012423 maintenance Methods 0.000 description 2
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- 238000005070 sampling Methods 0.000 description 2
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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Abstract
The invention discloses a manufacturing process method of an air cooling pipeline of a thermal generator set, which comprises the following steps: according to the construction drawing, compiling an operation instruction book; performing plate rechecking, sequentially performing steel plate sand blasting, template manufacturing and template checking, and sequentially performing sheet metal unfolding, allowance control and typesetting programming; splicing plates, carrying out numerical control blanking and manual blanking, and carrying out net size blanking and barren material remaining blanking; rolling and forming, wherein a straight pipe is formed at one time and subjected to iron sheet template inspection, cone section is formed in a region-by-region mode and subjected to three-dimensional template inspection and chord length real-time monitoring, and a guide plate is rolled and subjected to iron sheet template inspection; performing curvature inspection, secondary material marking, perimeter inspection, leading head cutting and ellipticity inspection; the integral assembly is carried out, including elbow assembly, three-way assembly and four-way assembly; performing size rechecking; welding and flaw detection are carried out; polishing and mating; the effect is as follows: the manufacturing quality of the air cooling pipeline is ensured.
Description
Technical Field
The invention relates to the technical field of pipeline manufacturing, in particular to a manufacturing process method of an air cooling pipeline of a thermal generator set.
Background
The air cooling pipeline of the thermal generator set has a complex structure, a plurality of special-shaped parts, such as an elbow and a tee joint, are difficult to loft and shape, and especially the manufacturing process of the semi-closed steam distribution pipeline is more difficult to manufacture. For this reason, for such engineering practice, a fabrication process for this engineering was developed. The effect of the technology is obvious in the manufacture of an air-cooled pipeline of a certain project, the technology is successful, and the technology adopts feasible technical measures and strict control means in the construction process to achieve the expected effect.
Disclosure of Invention
Therefore, the invention provides a manufacturing process method of an air cooling pipeline of a thermal generator set, which aims to solve the problems in the prior art.
In order to achieve the above object, the present invention provides the following technical solutions:
according to a first aspect of the invention, a manufacturing process method of an air cooling pipeline of a thermal generator set comprises the following steps: step S100, compiling an operation instruction book according to the construction drawing; step 200, performing plate rechecking, sequentially performing steel plate sand blasting, template manufacturing and template checking, and sequentially performing sheet metal unfolding, allowance control and typesetting programming; step S300, splicing plates, carrying out numerical control blanking and manual blanking, and carrying out net size blanking and barren material remaining blanking; step S400, rolling and forming, wherein a straight pipe is formed at one time and subjected to iron sheet template inspection, cone section is formed in a regional mode and subjected to three-dimensional template inspection and chord length real-time monitoring, and a guide plate is rolled and subjected to iron sheet template inspection; s500, performing curvature inspection, secondary material marking, perimeter inspection, leading head cutting and ellipticity inspection; step S600, performing integral assembly, including elbow assembly, three-way assembly and four-way assembly; step S700, performing size rechecking; step S800, welding and flaw detection are carried out; and step S900, polishing and delivering work.
Further, in the sheet metal expansion process of step S200, the expansion of the straight section cylinder section is performed according to the pitch diameter expansion, and manual lofting is adopted, so that welding shrinkage allowance and field installation allowance are reserved; the method comprises the steps of adjusting the track of actual cutting in the metal plate expansion of an elbow, namely, intermittently taking points and lofting the elbow according to the principle that the difference value of the arc length and the chord length is less than or equal to 5mm, wherein the actual point taking interval is 50-100mm, lofting the section of a shovel groove by taking the pitch diameter as a reference, and expanding the section of a non-shovel groove by taking an actual contact surface; the unfolding of all the components is marked with graduation lines of 90 degrees, 180 degrees, 270 degrees and 360 degrees; the rolled components are ensured to be consistent and meet the drawing requirements; the inclination deviation of the end face is not more than 1% of the outer diameter and is less than or equal to 3mm; when the allowable deviation of the circumference of the elbow is that the nominal diameter is larger than 1000mm, the allowable deviation is +/-6 mm; when the nominal diameter is less than or equal to 1000mm, the allowable deviation is +/-4 mm; the three-way expansion meets the drawing requirements and is divided into a large opening, a small opening, an embedded section, a diversion bend and a straight section at the lower part, wherein the straight section cylinder section is manufactured firstly, and secondary material marking is performed after molding.
Further, in the rolling and forming process of step S400, for the rolling of the straight section, only the iron sheet template is used for correction, and graduation lines of 90 °, 180 °, 270 ° and 360 ° are marked, and for the continuous change of the curvature of each point of the large and small openings in the cone section and the arc length direction, two three-dimensional templates are adopted to ensure the accuracy of the taper; when pre-bending, a leading plate is arranged; when centering, a normal line is formed on the cylinder body at intervals of 100mm by taking a small opening as a reference, and when rolling, the normal line is always positioned on a plane perpendicular to the side roller with the upper roller line of the four-roller machine, and the rolling direction is always rolled according to the normal line by taking the middle of the adjacent three normal lines as a reference; in the rolling process, each rolling area is respectively compared with a template and the chord length is measured, wherein the chord length measuring method is to measure the chord length between the end head and the normal line of the center of the rolled area; the butt joint longitudinal seam is not more than 10% of the wall thickness and not more than 3mm; the butt joint longitudinal seam 200mm away from the pipe end is not more than 2mm; other parts must not be larger than 1mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 1% of the outer diameter of the coiled pipe and not more than 3mm, and the flatness deviation of the straight pipe per meter is not more than 2mm; when in correction, after each section of cylinder is pressed by the tire film for the first time, checking the molding error amount by using a three-dimensional template, and adding a correction lath according to the molding error amount to give correction; if the strip is added, the barrel body is changed regularly, the rebound quantity of each time is inspected, the strip can be directly corrected, if the irregular change exists in the part of the barrel body, the strip is additionally added to correct the part of the barrel body, meanwhile, a forming contour line is drawn on the barrel body by using a three-dimensional template, a size check point is determined, and the local forming check is directly carried out by using the size.
Further, before the overall assembly in step S600, the requirements to be satisfied are: the circumference and drawing error of the joint of the field splice is not more than 2mm, and the ellipse is not more than 5mm; at the joint of the in-field splicing, the error of two adjacent ends is not more than 2mm, and the ellipse is not more than 5mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 2mm, and the flatness deviation of the straight pipe per meter is not more than 2mm; after each section of cylinder is qualified in treatment, preassembly can be carried out, the whole assembly must be carried out on solid ground, and an assembly operation platform should be laid before the assembly, and the assembly operation platform is carried out from bottom to top in a sectional manner.
Further, in step S600, assembling and welding the semi-closed pipeline, manufacturing a mold before rolling, wherein the main beam of the mold should be i-steel and calibrated to be within ±2mm, and adopting a reverse deformation measure in the assembling process, and checking the accuracy of the dimension at any time in the mold welding process; after welding, the mould is leveled and firmly fixed to prevent displacement.
Further, in step S600, during the assembling process of the side plate and the cylinder, the welding correction and the size inspection of the cylinder are performed before the assembling process, and the inner slope of the cylinder is inspected, trimmed and polished; converting the assembly size of the side plate and the cylinder into a measurable size and marking the measurable size on a workshop manufacturing drawing; the side plates and the assembly mould are firmly fixed, positioning points are drawn on the side plates, assembly lines are drawn along the length direction, and temporary supports are welded; and (3) hanging the side plate on the cylinder, aligning the center and the positioning size, checking the welding gap between the side plate and the cylinder, and spot-welding the cylinder and the side plate.
Further, after the whole assembly in step S600 is completed, assembly inspection is performed: the upper opening of the steel plate of the cylinder body should be horizontal, the height difference is less than or equal to 4mm, and the vertical height difference of the cylinder body is checked to +/-5 mm.
Further, after the integral assembling in step S600 is completed, performing assembling inspection further includes: the deviation between the radius of the steel plate ring of the shell and the design value is +/-5 mm.
Further, after the integral assembling in step S600 is completed, performing assembling inspection further includes: checking site pairing interface ovality, wherein the maximum and minimum diameter difference is not more than 2D/1000, and D is the designed diameter.
Further, after the integral assembling in step S600 is completed, performing assembling inspection further includes: the technical requirements of the butt joint misalignment amount and the gap at the end of the groove in the assembly should meet the requirements of electric welding, and the transverse seam is less than or equal to 3mm; the vertical seam is less than or equal to 3mm; the limit deviation of the end part of the groove is +/-3 mm.
The invention has the following advantages: the convenient installation and use are taken as basic starting points, and are assisted by practical technical measures, so that the manufacturing quality of the air cooling pipeline is ensured.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those of ordinary skill in the art that the drawings in the following description are exemplary only and that other implementations can be obtained from the extensions of the drawings provided without inventive effort.
The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the invention, which is defined by the claims, so that any structural modifications, changes in proportions, or adjustments of sizes, which do not affect the efficacy or the achievement of the present invention, should fall within the ambit of the technical disclosure.
Fig. 1 is a flowchart of a manufacturing process method of an air cooling pipeline of a thermal generator set according to some embodiments of the present invention.
Fig. 2 is a cutting and lofting diagram of a flow guiding component of a manufacturing process method of an air cooling pipeline of a thermal generator set according to some embodiments of the present invention.
Fig. 3 is a flow-guiding three-way assembly and a blanking diagram of a manufacturing process method of an air cooling pipeline of a thermal generator set according to some embodiments of the present invention.
Fig. 4 is a normal line diagram of a middle-size air cooling pipeline manufacturing process method for a thermal generator set according to some embodiments of the present invention.
Fig. 5 is a winding pattern of a manufacturing process method of an air cooling pipeline of a thermal generator set according to some embodiments of the present invention.
Fig. 6 is a schematic diagram illustrating a calibration method for manufacturing an air cooling pipeline of a thermal generator set according to some embodiments of the present invention.
Fig. 7 is a flow chart illustrating the assembly of an elbow in a process for manufacturing an air cooling pipeline of a thermal power generating unit according to some embodiments of the present invention.
Detailed Description
Other advantages and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, by way of illustration, is to be read in connection with certain specific embodiments, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 to 7, a manufacturing process method of an air cooling pipeline of a thermal generator set in this embodiment includes the following steps: step S100, compiling an operation instruction book according to the construction drawing; step 200, performing plate rechecking, sequentially performing steel plate sand blasting, template manufacturing and template checking, and sequentially performing sheet metal unfolding, allowance control and typesetting programming; step S300, splicing plates, carrying out numerical control blanking and manual blanking, and carrying out net size blanking and barren material remaining blanking; step S400, rolling and forming, wherein a straight pipe is formed at one time and subjected to iron sheet template inspection, cone section is formed in a regional mode and subjected to three-dimensional template inspection and chord length real-time monitoring, and a guide plate is rolled and subjected to iron sheet template inspection; s500, performing curvature inspection, secondary material marking, perimeter inspection, leading head cutting and ellipticity inspection; step S600, performing integral assembly, including elbow assembly, three-way assembly and four-way assembly; step S700, performing size rechecking; step S800, welding and flaw detection are carried out; and step S900, polishing and delivering work.
Aiming at the characteristics and difficulties of the construction, the whole construction process is subdivided and optimized, and the process flow for manufacturing the air cooling pipeline is obtained by combining the requirement of field installation, wherein the process flow is shown in the figure 1.
Throughout the whole process, we can find that the sheet metal is unfolded and the semi-closed pipeline is rolled and formed in the pipeline manufacturing process, and the assembly of the elbow and the tee joint is the three most important stages in the construction process: firstly, the sheet metal unfolding is a precondition point of the whole engineering, and the precision of the sheet metal unfolding not only meets the design requirement, but also has to meet the precision requirement of convenient coiling and convenient assembly; secondly, the forming and correction of the pipeline plays a role in the whole construction process after the front opening, and is a central link of the construction; finally, the assembly of the semi-closed pipeline, the elbow and the tee joint is the last inspection of construction quality; by preassembling, all previously unrepresented problems are reflected at this point.
Aiming at the problems which possibly occur and already occur in the construction process, the technical points of the air cooling pipeline construction are summarized as follows.
As shown in fig. 2, the sheet metal expansion of the elbow is the basis of the project, and the precondition for the expansion is to know the actual lengths of all the lines making up the expansion diagram; considering that in the actual blanking assembly process, all solid line lengths are not possible or necessary to be solved, the actual cutting track is adjusted, namely, the intermittent sampling and lofting are carried out on the elbow according to the principle that the difference value between the arc length and the chord length is less than or equal to 5mm, and the actual sampling interval is 50-100mm; firstly, because the section of the elbow is a curve, the section of the shoveling groove is lofted by taking the pitch diameter as a reference, and the section of the shoveling groove is not spread by taking the actual contact surface (the high end of the inclined tube is lofted according to the lining Pi Fangyang, and the low end of the inclined tube is lofted according to the crust); secondly, in order to control the error of the pairing, all the components are unfolded and marked with index lines of 90 degrees, 180 degrees, 270 degrees and 360 degrees (2 mm notches are embedded in the numerical control cutting process); thirdly, considering the situation that cross welding seams occur in the assembling process and the mechanical property is balanced, the same elbow is unfolded in different modes (the butt joint position is formed by 90 degrees 180 degrees 270 degrees 360 degrees, but not only), and the rolled and formed components are ensured to be consistent and meet the drawing requirements; fourth, the inclination deviation of the end surface is not more than 1% of the outer diameter and is less than or equal to 3mm; fifth, the allowable deviation of the circumference of the elbow is in accordance with: when the nominal diameter is larger than 1000mm, the allowable deviation is +/-6 mm; when the nominal diameter is less than or equal to 1000mm, the allowable deviation is +/-4 mm.
Because the tee joint is complicated in molding, various tee joints are split and adjusted differently to ensure the assembly accuracy; no matter how the splitting and the adjustment are made, the drawing requirements are met, the rolling assembly is convenient, and the structure is effectively and reasonably differentiated; tee joint: the device comprises a large opening, a small opening, an embedded section, a diversion bend and a straight section at the lower part (a straight section cylinder section is manufactured firstly, and secondary material marking is performed after molding); fig. 3 shows, from top to bottom, a flow-guiding bend, an embedded section and a large and small orifice relief, respectively.
Therefore, for the structural complex component, the principle of manufacturing is to divide the structural complex component into simple and reliable single structural bodies, and then splice and assemble the structural complex component again by an effective process method; the method is difficult to split, the construction process is simplified and controllable, the equipment meets the requirements of the components, and more importantly, the construction requirements are met, the blanking precision of the components is improved, and the later rolling and assembling links are more convenient.
And (5) coiling and forming: the forming and correction of each cylinder section of the pipeline plays a role in the whole construction process after the front opening, and different rolling methods are adopted for different structural members; for the inclined cone frustum, the diversion bend and the embedded section, which belong to the straight section without taper, the rolling of the straight section is only corrected by an iron sheet sample plate, and an index line (90 degrees 180 degrees 270 degrees 360 degrees) is marked; however, for the big and small openings which belong to the cone section and the curvature of each point in the arc length direction is continuously changed, two (big and small) three-dimensional templates are needed to ensure the accuracy of the taper; the cone section is more complex than the straight section, and the manufacturing difficulty is higher; therefore, to ensure the manufacturing quality of the cylindrical section, especially the conical section, the quality of each process must be ensured, and the guarantee of the process quality is a reasonable and practical manufacturing process; taking the rolling working performance of the four-roller plate rolling machine and the taper and radian of the rolled plate into consideration, firstly, using a waste steel plate as a test paper, and after the taper is reached, performing formal rolling of the cone; the adjusting points, particularly the supporting rollers, should not be randomly disturbed in the normal rolling process.
Pre-bending: because only the contact part of the steel plate and the upper roller can be bent, the two ends of the steel plate cannot be bent, and the length of the two ends of the steel plate becomes a residual straight edge; the method for arranging the leading edge plate is most practical and effective through comprehensive consideration of equipment capacity, resource saving, construction period shortening and the like; the process not only solves the problem of the residual straight edges at the two ends of the single Zhang Luke, but also avoids the problem of the upturned two ends, particularly the two ends of the small opening, and lays a foundation for the subsequent preassembly.
Centering: as shown in FIG. 4, because of the particularity of the cone section, the normal line of each section of the cylinder body is not a parallel straight line when the normal line is reflected on the flat plate, when the cone section is rolled, firstly, the normal line is formed every 100mm by taking a small opening as a reference on the cylinder body; as shown in fig. 5, the normal line and the upper roller line of the four-roller machine are always on the plane perpendicular to the side rollers during rolling; the middle of the adjacent three normals is taken as a reference (ABC area is taken as a reference, BCD area is taken as a reference, and the like) and the rolling direction in the area is always rolled according to the normals; in the rolling process, each rolling area is respectively compared with a template and the chord length is measured, wherein the chord length measuring method is to measure the chord length of the end head A and the normal line of the center of the rolled area; for example, the AB chord length is measured after the ABC area is rolled, the AC chord length is measured after the BCD area is rolled, the rolling of the next area is performed after the former area meets the requirements of the template and the chord length, and the like, the KLM area is finally rolled, so that the AL chord length meets the requirements, and the AL is automatically overlapped into one edge to form a complete joint.
The non-adhering gap between the sample plate and the inner wall of the pipe meets the following regulations: the butt joint longitudinal seam is not more than 10% of the wall thickness and not more than 3mm; the butt joint longitudinal seam 200mm away from the pipe end is not more than 2mm; other parts must not be larger than 1mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 1% of the outer diameter of the coiled pipe and not more than 3mm, and the flatness deviation of the straight pipe per meter is not more than 2mm; the method well ensures the rolling of the cone section, particularly avoids the problem of angle crossing of the cylinder body in the rolling process, and greatly reduces the correction amount; the method well ensures the rolling of the cone section, particularly avoids the problem of angle channeling of the cylinder body in the rolling process, and greatly reduces the correction amount.
And (3) correction: in the rolling process, the situation of over-bending or insufficient curvature is unavoidable, and the forming defects at each position of the cylinder body can be found through the inspection of the three-dimensional template; correction becomes an indispensable maintenance means; there are no non-two types of maintenance methods: hot pressing and cold pressing; the hot pressing is flame correction, the cylinder after hot pressing has good forming effect and very small rebound quantity, the cylinder after cold pressing has quite unsatisfactory forming effect, the rebound quantity is relatively large, sometimes rebound conditions are inconsistent and uneven, and the cylinder can not be formed by cold pressing at one time generally, and the cylinder can be finally formed by correcting through a flame correction method; however, most of the cylinders are fed with net size, flame correction inevitably generates a certain shrinkage, so that the assembled size is changed, and the annealing is equivalent to the primary annealing of the hot-press corrected part, so that specific technical indexes of base materials are changed, the instability of later use is increased, and the primary selection is made for ensuring the construction quality and cold press molding.
In the process of winding the cylinder body, a cold press molding process is required to be adopted; in order to control the cold press molding quality, the following method is adopted: after each section of cylinder is pressed by the tire membrane for the first time, checking the molding error by using a three-dimensional template; correction is given by adding correction slats according to the amount of molding error see fig. 6; (the width of the correction plate strip is 40mm, the thickness is determined by an error value, the number of the plate strips can be increased according to actual conditions, and the pressing sequence is that the height direction is corrected firstly, and then the upper opening and lower opening directions are corrected); if the barrel body is regularly changed after the battens are added, the resilience amount of each time is inspected, the battens can be directly corrected, and if the local part of the barrel body has irregular change, the battens are additionally added for correction; meanwhile, a forming contour line is drawn on the cylinder body by using a three-dimensional template, a size check point is determined, and local forming check is directly carried out by using the size; by implementing the process, the technical difficulty of cold pressing of the cone-section cylinder is well solved, and good conditions are provided for the assembly of the next stage.
Attention is also paid to the following problems: the steel plate enters a roller of the plate bending machine, and the end line of the steel plate is parallel to the roller; therefore, a theodolite can be erected at the edge of the plate bending machine to correct; the descending speed of the press roller of the veneer reeling machine is slow, and the crown block is used for cooperation in the reeling process, so that the steel plate is prevented from sagging due to dead weight, deformation and radian formation are prevented; in the rolling process, templates are continuously used for checking the radian of the steel plate, and after the templates are completely matched, angle steel can be used for supporting to protect the radian of the steel plate.
The following requirements must be met before splicing to enter the splicing stage: the circumference and drawing error of the joint of the field splice is not more than 2mm, and the ellipse is not more than 5mm; at the joint of the in-field splicing, the error of two adjacent ends is not more than 2mm, and the ellipse is not more than 5mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 2mm, and the flatness deviation of the straight pipe per meter is not more than 2mm; after each section of cylinder is qualified, preassembling can be performed; the whole assembly is carried out on solid ground, and an assembly operation platform is paved before the assembly, and the assembly is carried out from bottom to top in a sectional manner.
The assembly of the elbow is shown in fig. 7, the assembly of the diversion elbow, the assembly of the elbow and the assembly of the tee joint assembly.
Assembling and welding a semi-closed pipeline: the semi-closed pipeline has no actual acting point, so that the accurate closing of the pipeline is difficult to ensure in the rolling process, and a mould is manufactured before rolling so as to ensure the closing precision of the pipeline; in order to ensure the dimensional accuracy of the two side plates, the side plates and the cylinder body are correspondingly arranged on the clamping fixture; therefore, the precision of the mould is particularly important; in order to ensure rigidity, the main beam of the clamping fixture should be made of I-steel; and correcting the deformation to be within +/-2 mm, and adopting proper anti-deformation measures (the dimension of two ends of the mould is generally +3mm, and the dimension of the middle part is preferably-3 mm) in the assembly process; checking the accuracy of the dimension at any time in the welding process of the mould to prevent deformation; after welding is finished, leveling the clamping fixture, and firmly fixing to prevent displacement; the length of the mould should meet the requirement of manufacturing the longest section of cylinder.
And (5) shell ring rolling: a template with 1/4-1/6 circumference is needed before the coiled pipe to check the roundness of the coiled pipe; the sizing is needed to be mastered during pre-bending, a template card time reference is needed to be used, the bending angle is processed no matter the size, and the next working procedure can be carried out after the bending angle meets the requirements; when the round is rolled, the round is not required to be in place once, and the round is subjected to slight correction by a plurality of turns to release stress, and a template is used for reference from time to time; the arc plate is directly added at the joint to ensure the roundness of the joint of the longitudinal joint; before the pipe is rolled, the cut iron oxide is cleaned; the cylindrical shell sections with larger deformation can be subjected to rounding by using a rolling machine after longitudinal seam welding is finished, so that the whole roundness of the cylindrical shell sections, the misalignment variable of the ring and the longitudinal seam are ensured to be in a standard range; after the rolling, a multidirectional support (available waste) is arranged on each cylinder section at a distance of about 200mm from the pipe orifice so as to absolutely ensure that each section of cylinder section does not generate large elastic deformation and plastic deformation before and during the assembly.
And (3) barrel assembly: before assembly, the batching list is strictly checked to see whether longitudinal seams are staggered by more than 200mm and the positions of on-site perforating holes are staggered according to the design requirement or not in addition to correcting the deformation generated by welding and raw materials, and the circumferential seam distance of a steam pipe section is at least 500mm; during assembly, the fixture is used for fastening parts so as to control the assembly and welding gaps, and the method of positioning the spot welding fixture is not used; converting the drawing angle size into a measurable size during assembly; strictly checking and controlling the misalignment amount; the cylinder body formed by the cylinder sections is assembled on a special platform or mould, so that the circumferences of the two ends and the center line sample punching points are mutually aligned, the straight line of each cylinder section after the cylinder section is assembled is ensured, and an oblique pull support is arranged in the first cylinder section, so that the ovality of the pipe orifice is ensured.
Welding sequence: single pass weld welding sequence: the inner side adopts submerged arc automatic welding and manual arc welding (when the assembly clearance cannot meet the requirement of the submerged arc automatic welding, the outer side adopts manual arc welding to weld a temporary bottom sealing weld joint), the back side is back-gouged, and the outer side adopts submerged arc automatic welding and manual arc welding; welding sequence of the cylinder: single section longitudinal seam, circular seam between sections; each section of pipeline is provided with 2 lifting lugs, the lifting lugs are arranged at positions to ensure that the lifted pipeline is horizontal and stressed uniformly, the size and thickness of a backing plate of each lifting lug are calculated, the welding angle of each lifting lug is required to meet the requirement and the coloring flaw detection is required to be carried out when the welding is carried out by staggering the circumferential seam and the longitudinal seam by more than 200 mm; the pipeline numbers are written according to the component numbers of the layout, and the numbers are sprayed at the position 100mm away from the pipe port by using a marker pen or paint; the assembly of the eccentric big and small head should be strictly checked and controlled and the preassembly confirmation should be carried out after the manufacture is completed.
The side plate is assembled with the cylinder body: before assembling, performing barrel welding correction, size inspection, inner slope inspection, trimming, polishing and the like on the barrel; converting the assembly size of the side plate and the cylinder into a measurable size and marking the measurable size on a workshop manufacturing drawing; special attention is paid to the fitting dimensions at the big and small heads; the side plates and the assembly mould are firmly fixed, positioning points are drawn on the side plates, assembly lines are drawn along the length direction, and temporary supports are welded; the length of the side plates should be ensured to avoid affecting the assembly of the sealing plate; grinding the butt welding seam on the inner side of the side plate; hanging the side plate on the cylinder, aligning the center and the positioning size, checking the welding gap between the side plate and the cylinder, and spot-welding the cylinder and the side plate; and (5) assembling and aligning the cylinder body and the side plates.
The inner support and the outer reinforcing ring/adjusting ring are assembled (the welding of the outer reinforcing ring/adjusting ring and the side plates is carried out after the side plates are straightened); an internal support is additionally arranged at the open end of the cylinder body to prevent the open deformation; the side plates and the reinforcing rings/adjusting rings should be tightly jointed when in combination, so that the excessive gap between the side plates and the reinforcing rings/adjusting rings is avoided, and larger deformation is caused during welding; the welding holes of the outer reinforcing ring, the inner support and the side plates are large enough (R is larger than 25mm or the position is welded for a certain period) to ensure the continuity and the penetration of the welding lines of the side plates; the consistency/straightness of the drawing position and the bolt hole position of the outer reinforcing ring is ensured; the inspection tolerance of the distance between the two reinforcing rings and the distance between the reinforcing rings and the pipe end is 2 per mill, and the distance must not be skewed so as to ensure the smooth installation of other accessories on site; assembling a support; the position of the support (especially the fixed support) and the bolt holes on the support should be strictly controlled; welding deformation adjustment of the support base plate; the adjusting ring reduces splicing as much as possible, and the adjusting ring is welded with the cylinder body after double-groove ground assembly welding and magnetic powder detection is qualified; a single-sided groove is formed at the joint of the adjusting ring and the side plate; the adjusting ring is arranged on one side of the reducing part and the inner diameter of the adjusting ring is not larger than the design size in order to facilitate field installation and better control the roundness of the reducing part; the sealing plate is assembled, the groove is formed in the cylinder body, the size of the sealing plate and the drain hole are confirmed, and the position and the levelness/verticality of the sealing plate are ensured during assembly; welding lines with the side plates (the outer side is easy to leak welding or can not be welded well because the support blocks the space, a method for properly trimming the side plates or a front-back welding sequence of the support and the sealing plate can be coordinated) can be adopted, and the side plates are welded after being straightened; since the sealing plate is positioned inside the steam pipeline, the sealing plate is difficult to check and repair once leakage occurs in the field, and therefore, the welding seam is required to be subjected to magnetic powder detection to ensure the welding quality.
The welding sequence is as follows: the welding of the side plate and the cylinder body in a pairing manner, the welding of the inner support, the welding of the adjusting ring/reinforcing ring/support/sealing plate, the inner welding line (important inspection and control) of the side plate and the cylinder body, the outer welding line of the side plate and the cylinder body, and the welding of the side plate and the adjusting ring/reinforcing ring/sealing plate; assembling accessories, wherein the wind wall connecting plates are on the same straight line and inclined at an angle; and the height of the welding seam should be enough; manhole assembly, attention to the arrangement direction of the flange holes, and the welding seams of the reinforcing plates cannot coincide with the welding seams of the cylinder body, and the welding seams are staggered by 100mm; adjusting the tire removal, leveling the width direction of the side plates, adjusting the straightness (1/1000 and maximum 10 mm) of the length direction, and adjusting the size of the upper opening and the lower opening (the checking key points are the joint of the upper opening and the lower opening and the tube bundle), wherein the checking of the whole size of the cylinder meets the standard requirement; finishing welding seams of the side plates, the adjusting rings, the reinforcing rings and the sealing plates after the side plates and the adjusting rings are qualified; leakage inspection of welding seams of the side plates and the cylinder; the supports on the cylinder sections at the two ends of each section of cylinder prevent large deformation.
And performing trial assembly on the adjacent barrel ports on the same platform, and performing trial assembly on at least the first row of the barrel ports so as to find deviation and correct in time.
After sectional assembly, the total height and the angle among the cylinder hole, the supporting seat and the turning point are required to be ensured to meet the design requirements, and the subsequent process can be carried out; the permissible deviation of each part is as follows: the deviation value of the center of the steel plate ring of the cylinder body to the checking center on the assembly platform is less than or equal to 1/1000H and less than or equal to 10mm; the upper opening of the steel plate of the cylinder body is horizontal, and the height difference is less than or equal to 4mm; checking the vertical height difference of the cylinder body to +/-5 mm; the deviation between the radius R of the steel plate ring of the shell and the design value is +/-5 mm; checking site pairing interface ovality, wherein the maximum and minimum diameter difference is not more than 2D/1000 (D is the designed diameter); the technical requirements of the butt joint misalignment amount and the gap between the end parts of the grooves in the assembly should meet the requirements of electric welding: the transverse seam is less than or equal to 1/10t (t is the thickness of the steel plate) and is not more than 3mm; the vertical seam is less than or equal to 3mm; the limit deviation of the end part of the groove is +/-3 mm.
After the cylinder is preassembled and adjusted, sample punching marks are punched at the assembling positions of two sections of cylinder sections of the field assembly interface for delivery.
While the invention has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.
The terms such as "upper", "lower", "left", "right", "middle" and the like are also used in the present specification for convenience of description, but are not intended to limit the scope of the present invention, and the changes or modifications of the relative relationship thereof are considered to be within the scope of the present invention without substantial modification of the technical content.
Claims (9)
1. The manufacturing process method of the air cooling pipeline of the thermal generator set is characterized by comprising the following steps of:
step S100, manufacturing an operation instruction book according to the construction drawing;
step 200, performing plate rechecking, sequentially performing steel plate sand blasting, template manufacturing and template checking, and sequentially performing sheet metal unfolding, allowance control and typesetting programming;
step S300, splicing plates, carrying out numerical control blanking and manual blanking, and carrying out net size blanking and barren material remaining blanking;
step S400, rolling and forming, wherein a straight pipe is formed at one time and subjected to iron sheet template inspection, cone section is formed in a regional mode and subjected to three-dimensional template inspection and chord length real-time monitoring, and a guide plate is rolled and subjected to iron sheet template inspection;
s500, performing curvature inspection, secondary material marking, perimeter inspection, leading head cutting and ellipticity inspection;
step S600, performing integral assembly, including elbow assembly, three-way assembly and four-way assembly;
step S700, performing size rechecking;
step S800, welding and flaw detection are carried out;
step S900, polishing and delivering work;
in the sheet metal expansion process of the step S200, the expansion of the straight section cylinder section is performed according to the intermediate diameter expansion, and manual lofting is adopted, so that welding shrinkage allowance and field installation allowance are reserved;
the method comprises the steps of adjusting the track of actual cutting in the metal plate expansion of an elbow, namely, intermittently taking points and lofting the elbow according to the principle that the difference value of the arc length and the chord length is less than or equal to 5mm, wherein the actual point taking interval is 50-100mm, lofting the section of a shovel groove by taking the pitch diameter as a reference, and expanding the section of a non-shovel groove by taking an actual contact surface; the unfolding of all the components is marked with graduation lines of 90 degrees, 180 degrees, 270 degrees and 360 degrees; the rolled components are ensured to be consistent and meet the drawing requirements; the inclination deviation of the end face is not more than 1% of the outer diameter and is less than or equal to 3mm; when the allowable deviation of the circumference of the elbow is that the nominal diameter is larger than 1000mm, the allowable deviation is +/-6 mm; when the nominal diameter is less than or equal to 1000mm, the allowable deviation is +/-4 mm;
the three-way expansion meets the drawing requirements and is divided into a large opening, a small opening, an embedded section, a diversion bend and a straight section at the lower part, wherein the straight section cylinder section is manufactured firstly, and secondary material marking is performed after molding.
2. The manufacturing process of air-cooled pipeline of thermal generator set according to claim 1, wherein in the rolling and shaping process of step S400, only iron sheet templates are used for correcting the straight section rolling, graduation lines of 90 °, 180 °, 270 ° and 360 ° are marked, and for the continuous change of curvature of each point of the big and small openings belonging to the cone section and the arc length direction, two three-dimensional templates are used for ensuring the accuracy of taper;
when pre-bending, a leading plate is arranged;
when centering, a normal line is formed on the cylinder body at intervals of 100mm by taking a small opening as a reference, and when rolling, the normal line is always positioned on a plane perpendicular to the side roller with the upper roller line of the four-roller machine, and the rolling direction is always rolled according to the normal line by taking the middle of the adjacent three normal lines as a reference; in the rolling process, each rolling area is respectively compared with a template and the chord length is measured, wherein the chord length measuring method is to measure the chord length between the end head and the normal line of the center of the rolled area; the butt joint longitudinal seam is not more than 10% of the wall thickness and not more than 3mm; the butt joint longitudinal seam 200mm away from the pipe end is not more than 2mm; other parts must not be larger than 1mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 1% of the outer diameter of the coiled pipe and not more than 3mm, and the flatness deviation of the straight pipe per meter is not more than 2mm;
when in correction, after each section of cylinder is pressed by the tire film for the first time, checking the molding error amount by using a three-dimensional template, and adding a correction lath according to the molding error amount to give correction; if the strip is added, the barrel body is changed regularly, the rebound quantity of each time is inspected, the strip can be directly corrected, if the irregular change exists in the part of the barrel body, the strip is additionally added to correct the part of the barrel body, meanwhile, a forming contour line is drawn on the barrel body by using a three-dimensional template, a size check point is determined, and the local forming check is directly carried out by using the size.
3. The process for manufacturing the air-cooled pipeline of the thermal generator set according to claim 1, wherein before the integral assembly in the step S600, the requirements to be met are as follows: the circumference and drawing error of the joint of the field splice is not more than 2mm, and the ellipse is not more than 5mm; at the joint of the in-field splicing, the error of two adjacent ends is not more than 2mm, and the ellipse is not more than 5mm; the vertical allowable deviation between the end face of the coiled pipe and the central line is not more than 2mm, and the flatness deviation of the straight pipe per meter is not more than 2mm; after each section of cylinder is qualified in treatment, preassembly can be carried out, the whole assembly must be carried out on solid ground, and an assembly operation platform should be laid before the assembly, and the assembly operation platform is carried out from bottom to top in a sectional manner.
4. The manufacturing process of air-cooled pipelines of thermal generator sets according to claim 3, wherein in step S600, semi-closed pipelines are assembled and welded, a mould is manufactured before coiling, the main beam of the mould is made of I-steel and calibrated to be within +/-2 mm, an anti-deformation measure is adopted in the assembling process, and the accuracy of the dimension is checked at any time in the welding process of the mould; after welding, the mould is leveled and firmly fixed to prevent displacement.
5. The method for manufacturing an air-cooled pipeline of a thermal generator set according to claim 4, wherein in the step S600, in the process of assembling the side plates and the cylinder, the cylinder is welded, corrected and checked in size before assembling, and the inner slope of the cylinder is checked, trimmed and polished; converting the assembly size of the side plate and the cylinder into a measurable size and marking the measurable size on a workshop manufacturing drawing; the side plates and the assembly mould are firmly fixed, positioning points are drawn on the side plates, assembly lines are drawn along the length direction, and temporary supports are welded; and (3) hanging the side plate on the cylinder, aligning the center and the positioning size, checking the welding gap between the side plate and the cylinder, and spot-welding the cylinder and the side plate.
6. The process for manufacturing the air-cooled pipeline of the thermal generator set according to claim 1, wherein after the integral assembly in the step S600 is completed, assembly inspection is performed: the upper opening of the steel plate of the cylinder body should be horizontal, the height difference is less than or equal to 4mm, and the vertical height difference of the cylinder body is checked to +/-5 mm.
7. The process for manufacturing an air-cooled pipeline of a thermal generator set according to claim 6, wherein after the integral assembling in step S600 is completed, performing assembling inspection further comprises: the deviation between the radius of the steel plate ring of the shell and the design value is +/-5 mm.
8. The process for manufacturing an air-cooled pipeline of a thermal generator set according to claim 7, wherein after the integral assembling in the step S600 is completed, performing assembling inspection further comprises: checking site pairing interface ovality, wherein the maximum and minimum diameter difference is not more than 2D/1000, and D is the designed diameter.
9. The process for manufacturing an air-cooled pipeline of a thermal generator set according to claim 8, wherein after the integral assembling in step S600 is completed, performing assembling inspection further comprises: the technical requirements of the butt joint misalignment amount and the gap at the end of the groove in the assembly should meet the requirements of electric welding, and the transverse seam is less than or equal to 3mm; the vertical seam is less than or equal to 3mm; the limit deviation of the end part of the groove is +/-3 mm.
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| CN113305513A (en) * | 2021-06-09 | 2021-08-27 | 中国电建集团四川工程有限公司 | On-site factory manufacturing construction method for circulating water pipeline |
| CN113351686B (en) * | 2021-06-21 | 2022-12-27 | 中国船舶重工集团柴油机有限公司 | Method for correcting low-pressure outer cylinder combined front guide plate of gas turbine |
| CN114406623B (en) * | 2022-02-28 | 2023-09-22 | 凯奇集团有限公司 | Forming method of stainless steel sliding tube elbow |
| CN115302118A (en) * | 2022-08-12 | 2022-11-08 | 哈尔滨锅炉厂有限责任公司 | Forming method of circular arc tube panel |
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