CN112815224A

CN112815224A - Construction method of water tank wet type vertical lifting gas holder and water tank wet type vertical lifting gas holder

Info

Publication number: CN112815224A
Application number: CN202110012569.XA
Authority: CN
Inventors: 赵鹏龙; 万莹; 代明
Original assignee: China Eleventh Chemical Construction Co Ltd
Current assignee: China Eleventh Chemical Construction Co Ltd
Priority date: 2021-01-06
Filing date: 2021-01-06
Publication date: 2021-05-18

Abstract

The application provides a construction method of a water tank wet-type vertical lift gas holder and the water tank wet-type vertical lift gas holder, which relate to the field of chemical equipment and comprise the following steps: prefabricating, namely preprocessing a sample plate and forming members for forming a bottom plate, a wall plate and a top plate, wherein the forming members for forming the bottom plate, the wall plate and the top plate comprise arc-shaped pieces to be detected; and aiming at least part of the arc-shaped structural part in the template, taking the first one of the curvature radius and the chord length of the part to be detected corresponding to the arc-shaped structural part as a constraint condition, and constraining the second one of the curvature radius and the chord length of the arc-shaped structural part. The application provides a basin wet-type helicopter gas holder construction method, the prefabrication processing step carries out reasonable prefabrication to the required part of follow-up step, has both planned suitable prefabricated allowance in order to reduce the loss and the assembly degree of difficulty of material, makes the quantity of part be unlikely to too much again, and then has improved the efficiency of follow-up step under the condition of guaranteeing that the gas holder satisfies the requirement.

Description

Construction method of water tank wet type vertical lifting gas holder and water tank wet type vertical lifting gas holder

Technical Field

The application relates to the field of chemical equipment, in particular to a construction method of a water tank wet type vertical lift gas holder and the water tank wet type vertical lift gas holder.

Background

In the prior art, a construction method for a steel water tank wet type helicopter gas holder, for example, a steel water tank wet type helicopter gas holder construction method, lacks a scientific and effective plan, which causes that a process is easy to leak or complicate in a construction process of the steel water tank wet type helicopter gas holder, and may affect the completion quality of the steel water tank wet type helicopter gas holder or consume too much construction time.

Disclosure of Invention

A first objective of the present application is to provide a construction method of a wet-type gas helicopter case, so as to ensure high efficiency and high quality during the construction process of the wet-type gas helicopter case.

A second object of the present application is to provide a water tank wet type helicopter head, which is obtained by the above construction method.

In a first aspect, the present application provides a method of constructing a wet-type helicopter gas holder, the method comprising:

prefabricating, namely preprocessing a sample plate and forming components for forming a bottom plate, a wall plate and a top plate, wherein the forming components for forming the bottom plate, the wall plate and the top plate comprise an arc-shaped piece to be detected;

and aiming at least part of the arc-shaped structural part in the sample plate, taking the first one of the curvature radius and the chord length of the part to be detected corresponding to the arc-shaped structural part as a constraint condition, and constraining the second one of the curvature radius and the chord length of the arc-shaped structural part.

Preferably, in the prefabricating and processing step, under the condition that the curvature radius of the to-be-detected part corresponding to the arc-shaped structural part is smaller than or equal to 12.5m, the chord length below the arc-shaped structural part is not smaller than 1.5 m;

the length of at least part of the linear structural members in the sample plate is not less than 1 m.

Preferably, the prefabrication process further comprises:

the bottom plate is prefabricated according to the designed diameter amplification of 0.1% -0.2%;

the bottom plate comprises an arched edge plate, and butt joints of the arched edge plate are arranged at unequal intervals.

Preferably, the difference of diagonal lines, the edge length and the length of the symmetrical line segment of the wall plate have predetermined deviations respectively;

the difference of the diagonal lines, the edge length and the length of the symmetrical line segment of the arched edge plate have preset deviations respectively.

Preferably, the prefabrication process further comprises:

the guide rail is prefabricated, and the bending radian allowable deviation of the guide rail is +/-5 mm in the radial direction and +/-3 mm in the lateral direction.

Preferably, the construction method of the water tank wet type helicopter gas holder further comprises the following steps:

an assembling step of assembling the bottom plate, the wall plate and the top plate, respectively;

a lifting step of lifting the wall plate for installation;

and an installation step, namely installing the wall plate, a tower section and a bell jar of the water tank wet type helicopter gas holder, welding parts at corresponding positions, and installing the guide rail and accessories of the water tank wet type helicopter gas holder.

Preferably, the guide rail includes an inner rail such that a deviation of perpendicularity after installation of the inner rail in the installing step is not more than 7mm, and a radial deviation is not more than 6mm, and a tangential deviation is not more than 7 mm.

Preferably, the mounting step further comprises:

the guide rail comprises an outer guide rail, the verticality deviation of the installed outer guide rail is not more than 15mm, the radial deviation is not more than 10mm, and the tangential deviation is not more than 15 mm;

the contact surface of the outer guide rail and the guide wheel is provided with a concave-convex part not larger than 2 mm.

a testing step comprising one or more of a vacuum leak test, a weld repair test, a flush test, and a lift test for the base plate.

In a second aspect, the present application provides a water tank wet-type helicopter gas holder obtained by the water tank wet-type helicopter gas holder construction method as described above.

The application provides a basin wet-type helicopter gas holder construction method, the prefabrication processing step carries out reasonable prefabrication to the required part of follow-up step, has both planned suitable prefabricated allowance in order to reduce the loss and the assembly degree of difficulty of material, makes the quantity of part be unlikely to too much again, and then has improved the efficiency of follow-up step under the condition of guaranteeing that the gas holder satisfies the requirement.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, and it is preferably understood that the following drawings only illustrate some embodiments of the present application and are therefore not to be considered limiting in scope, and that for those skilled in the art, other related drawings may be obtained from these drawings without inventive effort.

Figure 1 shows a schematic view of a butt joint of arcuate edge plates;

FIG. 2 shows a schematic view of an arcuate edge plate sizing location;

FIG. 3 shows a schematic view of a wall panel sizing section;

fig. 4 shows a schematic view of a lifting device;

figure 5 shows a schematic view of the positioning device installation.

Reference numerals:

1-chain inversion; 2-hoisting the upright post; 3-tank body; 4-strip plates to be assembled; 5-lifted wall plate; 6-a wall plate to be lifted; 7-positioning blocks.

Detailed Description

The technical solutions of the present application will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Throughout the description of the present application, it is to be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, as if they were fixed or removable or integrally connected, for example; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In addition, technical solutions between the various embodiments can be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, the technical solutions are preferably considered to be absent from the combination, and are not within the protection scope of the present application.

In the following, a detailed description will be given of a method for constructing a water tank type helicopter gas holder, which may be a steel water tank type helicopter gas holder in the embodiment, and will be described as an example below. The construction method of the water tank type vertical lift gas holder comprises the following steps according to the implementation sequence: the prefabrication process, the assembly process, the lifting process and the installation process, which will be described in turn.

In an embodiment, the prefabrication process includes lofting and blanking operations, as follows.

The template for prefabrication and installation inspection of a steel water tank type helicopter gas holder (hereinafter referred to as a gas holder) meets the following requirements:

for the arc-shaped template, when the curvature radius of the components (such as the bottom plate, the wall plate and the top plate of the gas cabinet) is less than or equal to 12.5m, the chord length of the arc-shaped template is not less than 1.5 m; aiming at an arc sample plate for measuring the edge angle of a welding seam, the chord length is not less than 1 m;

aiming at the linear sample plate, the length of the linear sample plate is not less than 1 m;

the sample plate can be made of an iron sheet with the thickness of 0.5-0.7 mm, and preferably, the periphery of the iron sheet is smooth and neat so as to reduce the processing difficulty.

It should be noted that the gas holder prefabrication method and prefabrication process are carried out in a manner that does not damage the base material and reduces the performance of the base material. In the present embodiment, the steel plate cutting and the weld groove machining may be performed by machining or flame cutting, and the obtained machined surface is configured to be a flat surface, that is, at least, there are no defects such as slag inclusion, delamination, and cracks, and the oxide layer on the surface of the groove is removed.

Further, the member is subjected to deformation prevention, damage prevention and corrosion prevention during storage, transportation and on-site stacking of the member, and for example, for the deformation prevention, a prefabricated shape of the member may be maintained by using a prefabricated mold.

In an embodiment, the prefabrication process may be performed in sequence according to an installation sequence given by the following installation steps to meet the requirement of performing the construction process in order. And in order to further ensure the orderliness requirement of the construction process, the prefabricated components are respectively marked (such as the types of the components, the curvature radius of the components and the like) so as to facilitate the subsequent installation construction. For this, the prefabrication manner of each member is given below in the order of installation in the installation steps described below.

In the embodiment, when the bottom plate is prefabricated, the diameter of the bottom plate is preferably enlarged by 0.1-0.2% according to the designed diameter so as to compensate the welding shrinkage. As shown in fig. 1, fig. 1 shows a schematic view of the butt joint of the arched edge plates, wherein the butt joint of the arched edge plates adopts unequal gaps, i.e. the outer gap e1 may be 6mm to 7mm, and the inner gap e2 may be 8mm to 12 mm.

With further reference to fig. 2, fig. 2 presents a schematic view of an arcuate edge panel, wherein the line segment EF can be understood as the line segment traversed by the axis of symmetry of the arcuate edge panel. Wherein, the allowable deviation for the length AB (i.e. the length of the line segment AB, the same below) and the length CD satisfies + -2 mm, the allowable deviation for the widths AC, BD, EF satisfies + -2 mm, and the allowable deviation | AD-BC | for the difference of the diagonals is ≦ 3 mm.

Furthermore, for the edge panel of the base panel, the minimum cathetus dimension of the edge panel is no less than 700 mm; the width of the middle web plate at the bottom of the tank is not less than 1000mm, and the length of the middle web plate is not less than 2000 mm; the distance between any adjacent welding seams of the bottom plate is not less than 300 mm.

In the embodiment, when the wall panels are prefabricated, longitudinal welding seams of all the circles of wall panels are preferably staggered from circle to circle in the same direction, and the distance between the longitudinal welding seams of adjacent circles of wall panels is preferably 1/3 of the length of the wall panels and is not less than 300 mm. The distance between the longitudinal welding seam of the bottom ring wall plate and the butt welding seam of the tank bottom edge plate is not less than 300 mm. The longitudinal welding seam of the band plate is not covered by the upright post and is not less than 50mm away from the edge of the upright post. The distance between the edge-wrapping angle steel butt joint and the longitudinal welding seam of the wall plate is not less than 300 mm.

With further reference to fig. 3, the allowable deviation in panel dimensions meets the following requirements. Wherein the line segment KL is likewise passed through by the axis of symmetry of the wall panel shown in fig. 3. The tolerance for the widths GI, HJ and KL is + -1 mm, the tolerance for the lengths GH and IJ is + -1.5 mm, and the difference | GJ-HI | ≦ 2mm for the diagonal. In addition, with respect to the straightness, the allowable deviation of the straightness of the line segments GI and HJ is 1mm, and the allowable deviation of the straightness of the line segments GH and IJ is 2 mm.

In an embodiment, the arc-shaped plate-shaped member with the wall thickness of more than or equal to 4mm is preferably rolled by a roller bed, the end part of the steel plate is pre-bent according to the radian requirement before rolling, an arc template with the chord length of not less than 1.5m is used for inspection after rolling, and the gap of the arc-shaped plate-shaped member is not more than 2 mm.

When the wall plate of the bell jar is prefabricated, in order to compensate the girth welding shrinkage connected with the bell jar wall plate and the water tank wall plate edge-wrapping angle steel or channel steel, the upper belt plate is preferably discharged according to a right circular cone table, namely the diameter of an upper opening of the upper belt plate can be increased by 1/1000mm compared with the original design diameter. (for convenience of description, the requirement of the bell jar top plate is mentioned here in a compliant way, namely, when the bell jar top plate is blanked, the circumferential lap joint width is not less than 35mm, the radial lap joint width is not less than 25mm, and the lap weld is preferably staggered with each beam of the framework by more than 50 mm).

When the water seal is prefabricated, the water seal can be prefabricated in a segmented mode, radian deviation of an annular plate is checked by a sample plate with the chord length not less than 2m, a gap is not less than 3mm, and an included angle of interfaces at two ends is further calibrated. The vertical plate interface and the annular connecting plate are preferably staggered by more than 300 mm. Further, the sum of the arc lengths of the water seal prefabricated sections is preferably larger than the designed total length of 150-200mm to reserve a sufficient margin.

After the water seal is prefabricated, assembled and positioned in a segmented mode and welded, the diameter of the upper opening of the water seal is 5-7mm larger than the designed diameter, and the water seal is supported by section steel in a spot welding mode. The annular plate is preferably flattened during welding to prevent welding distortion. 500-800mm of non-welding is left at the mounting interface for mounting.

When the accessory is prefabricated, the following manner can be adopted. When the inner structure and the vault of the bell jar are installed, the support prefabrication can be pressed on a special mould by a hydraulic jack to form a designed radian, and then the support prefabrication is formed by tailor-welding. And hot bending and cold bending processes are adopted, the radian is corrected by lofting on a platform according to the diameter of part of designed accessories, the horizontal warping degree is checked, the radial allowable difference is +/-3 mm, and the horizontal warping is not more than 5 mm.

The radian gaps and the warps between the rest arc-shaped steel and the platform real sample are not more than 4 mm. The preferred and wallboard, the beam-column tip connection welding seam of staggering more than 150mm of the interface of angle ring or channel-section steel circle, and the preferred design week of preferred the length of its prefabricated circle sum of arc is grown by 200 ~ 300 mm. The gas holder stand is preferably straightened before blanking. The section warpage of the prefabricated stand column is not more than 2mm, and the longitudinal bending total length is not more than 3 mm. The thickness of the accessory formed by hot-bending (only without overburning and deterioration) is reduced by no more than 1 mm. The radial main beams and the radial secondary beams of the bell jar arch-shaped framework have length deviation of not more than 5mm after prefabrication and total length warping of not more than 10 mm.

When the guide rail is prefabricated, the allowance deviation of the bending radian of the guide rail after machining is as follows: radial of + -5 mm and lateral of + -3mm, otherwise cold correction is preferred. The inner guide rail and the outer guide rail are preferably straightened before blanking, the longitudinal bending total length after the inner guide rail is prefabricated is not more than 3mm, and the longitudinal bending total length after the outer guide rail is prefabricated is not more than 5 mm. The arc degree of the guide rail after being processed preferably meets the requirements of design drawings, and the phenomena of overburning, cracks, sharp bends and distortion which does not meet the design requirements are not caused accurately, and the depth of a hammering scar on the surface of the guide rail is not more than 1.5 mm. The butt welding seam of the base plate at the lower part of the guide rail is preferably welded before the butt welding with the guide rail, no misalignment exists between two butt-jointed plates, and the protruding parts of two surfaces need to be ground flat after welding. The guide rail and the base plate are preferably fixed by adopting tack welding after being assembled, and the integral welding is preferably carried out after the guide rail is installed in place.

In addition, when other components are prefabricated, the ladder and the platform counterweight frame meet the regulations of GB50205-2001 steel structure engineering construction and acceptance regulations. Each manhole is processed respectively in the prefabrication stage, and is provided with bolts. The air duct conforms to the prefabricated length and rechecks the appearance of the weld.

On the basis of the technical features described above, the assembling steps will be described in detail below.

Wherein, the bottom plate equipment can satisfy following requirement: the bottom plate is laid and then the cross center line is marked on the foundation, the lower surface of the bottom plate is preferably subjected to corrosion prevention according to requirements, the corrosion-resistant coating is not brushed within the range of 50mm away from the plate edge, and the center of the bottom plate of the gas holder coincides with the center of the foundation. Furthermore, when the bottom plate is laid, the middle web plate is laid firstly, and then the edge plate is laid. The middle web is laid preferably by laying a central lath, and laying laths from the central lath to two sides sequentially. And lap welding seams are arranged between the middle webs. The bottom plates are spliced into a whole for spot welding and positioning, the spot welding length is 30-50mm, the interval is 300-500mm, and the spot welding sequence is the same as the welding sequence.

After the bottom plate is assembled, the bottom plate is welded. The welding sequence of the bottom plate is as follows: firstly welding short welding seams of the middle web, symmetrically distributing welders, carrying out gap skip welding, then welding long welding seams of the middle web, symmetrically distributing welders, carrying out sectional backing welding from the center to the outside, and then welding butt welding seams of the edge plates. Welders are symmetrically distributed and gap skip welding is carried out. And finally, after the assembly of the water tank wall is finished and the annular fillet weld of the bottom ring wall plate and the bottom side plate is welded, the lap weld of the middle web plate and the edge plate is welded (the part, away from the short seam of the edge plate, of the long seam is preferably left for more than 500mm during the welding of the middle web plate, and is not welded temporarily, and the welding is carried out after the long seam and the edge plate are fixed in a point mode).

On the basis, the wallboard assembly can meet the following requirements. The radian of the prefabricated plate is preferably checked before the wall plate is assembled, and the prefabricated plate is required to be corrected again when the prefabricated plate does not meet the prefabrication requirement. The horizontal deviation of the upper openings of the two adjacent wall plates is not more than 2 mm. The horizontal deviation of any two points on the whole circumference is not more than 6 mm. The longitudinal welding seams of the wall plates are staggered with the guide rails, the longitudinal welding seams of two adjacent circles of plates do not meet, and the staggered distance is not less than 50 mm. The vertical deviation of the assembly of the belt plates is not more than 2mm per belt, and the local concave-convex degree of the wall plate of the bell jar is not more than 30 mm.

In addition, the allowable deviation of the verticality of the welded water tank wall plate is not more than 7mm, and the allowable deviation of the diameters of the uppermost belt plate and the lowermost belt plate is +/-10 mm. After the bell jar wall plate is assembled, the integral structure preferably conforms to the bell jar straightness (stand column position) tolerance less than 8mm, and the bell jar wall radius deviation (stand column position) is +/-5 mm.

Further, the band plate is installed by adopting a flip-chip method, assembling and welding are carried out from top to bottom circle by circle, the middle section is installed by the gas holder from section to section and from outside to inside from the wall of the water tank, and finally the bell jar is assembled. The bow-shaped edge plate of bottom plate is to seam nondestructive test after qualified, makes level along for the level gauge of wallboard location line and makes the record, then in border board department, install 500mm high buttress additional in last band board below to in and out the business turn over of constructor can also regard as the escape way, and the basin a week evenly distributed is followed in setting up of buttress, and the welding is again on the edge plate. In addition, the inner diameter circle of the water tank is found on the buttress, a stop block is spot-welded at intervals of 300mm, and then the wall plate is installed.

After the welding of the longitudinal weld of the upper belt plate of the water tank is completed, the line weight is used for aligning the verticality of the wall plate, then the edge-covering angle steel is installed, the ovality of the wall plate is adjusted after the installation of the edge-covering angle steel is completed, the ovality of the wall plate is fixed by temporary support, and the edge-covering angle steel is welded again. And then lifting the wall plates from top to bottom circle by circle, assembling and welding, and installing the water tank platform after welding. In addition, the positions of the inner and outer guide rails are drawn in advance.

The middle section wall construction process follows the construction process mentioned above. During construction, the uppermost band plate is installed firstly, then assembly welding is performed from top to bottom circle by circle, after all wall plates are welded, the position of the wall plates is increased to 1m by using lifting columns, temporary buttresses are removed, then formal gaskets are installed, the gaskets are uniformly distributed along the circumference and are 24 gaskets are installed according to drawings, and the levelness error of the gaskets on the whole circumference is not more than 10 mm. And then leading the circumferential line and the center line of the middle section wall plate and the bell jar wall plate to the lining, marking a water seal positioning line, arranging positioning angle steel and fixedly welding in a positioning way, then dropping the middle section wall plate on the lining, and starting assembly and fixed welding according to the alignment of the circular arcs. And drawing the position of the inner guide rail according to the size according to the layout drawing of the typesetting guide rail after the middle section wall plate group is welded.

In addition, in the gas holder installation from outside to inside construction, a plate needs to be left as a safety channel at the last strip plate of the water tank wall plate for installation, a section which is approximately 700mm away from the plate is not welded temporarily when a circular seam is welded, and the plate is welded again when an installation hole is closed. The mounting hole is preferably sealed after the bottom plate leakage test and the internal part are mounted, and the longitudinal seam is welded and then the circular seam is welded during sealing.

On the basis, the bell jar assembly can meet the following requirements. The assembly of the wall plate of the bell jar adopts a flip-chip method (the same as the assembly method of the wall of the water tank), a lower belt plate of the bell jar and a lower water sealing ring plate are firstly fixed in place, and the horizontal error of the lower water sealing bottom ring plate on the whole circumference is not more than 5 mm. Then, the upper belt plate of the bell is assembled, and then the middle wall plate is assembled. And after the bell jar wall plates are completely assembled, installing the stand columns. And installing a reinforced angle steel ring and edge-covered angle steel preferentially after the longitudinal seam of the belt plate on the bell jar wall plate is welded, and installing connecting angle steel of the arch truss and the bell jar wall plate after the spot welding of the angle steel is finished. Furthermore, the upper opening of the bell wall and the edge-covering angle steel ring meet the following requirements: the horizontal diameter of the inner diameter is allowed to deviate +/-10 mm, and the horizontal deviation of the upper opening of the wall plate is not more than 5 mm.

Furthermore, the vertical deviation of the bell jar strip plate assembly does not exceed 2mm per strip, the total verticality does not exceed 1/1000 with full height, and the local unevenness of the wall plate does not exceed 30 mm. The diameter deviation of the arch top edge ring beam is +/-10 mm. When the top truss of the bell jar is assembled, the central ring of the truss is properly lifted to 50-100 mm and fixed, then the main beam and the secondary beam are symmetrically assembled in sequence, and the geometric dimension is adjusted to be qualified and fixed by positioning welding, and then the assembly is welded. After the top truss of the bell jar is assembled, the symmetrical beams must be in line with a deviation of straightness at the ring of no more than 10 mm.

The ring-shaped plate at the edge is assembled firstly when the bell jar top plate is assembled, the ring-shaped plate is assembled and welded from the edge to the center in sequence after welding, the lapping size of the top cover plate is 50mm, the seam is preferably clung, and the local maximum gap is not more than 1 mm. And (3) welding sequence: firstly, radial welding seams are welded, then girth welding seams are welded (pushed from the outer ring to the center), and finally welding seams connected with the annular plate are welded. And 3, sheet welding, wherein the inside and the outside of the same welding line are not welded simultaneously so as to avoid overlarge deformation.

On this basis, the present application further describes the welding of the wall panels. The wall plate is preferably welded with longitudinal welding seams firstly and then welded with circumferential welding seams, after the longitudinal welding seams of two adjacent circles of wall plates are welded, the circumferential welding seams are welded, welders are preferably uniformly distributed, and welding is carried out along the same direction. The water tank upper layer belt plate is placed on the buttress, then longitudinal joint assembly is carried out, after assembly, before welding, an arc-shaped back plate is added to a longitudinal weld in the water tank wall, and an equipment bar is added to a longitudinal joint outside the water tank wall, so that post-welding angular deformation is prevented. When the longitudinal seam is welded, the middle section of the welding seam is preferably welded firstly, and then the longitudinal seam is welded in sections.

Further, the following process will be included for the lifting step below. Firstly, a lifting device is arranged, and a lifting process flip-chip method is utilized, and the lifting device has the following characteristics: the construction method of lifting and inverting the large storage tank can reduce labor intensity, accelerate lifting speed, reduce construction cost, and is safe and reliable. The equipment is shaped, can be used in a turnover way, can be flexibly combined according to the size of the storage tank, and is suitable for manufacturing an inner floating roof, a vault, a floating roof tank, a polygonal storage tank and steel structure inversion construction. Compared with an inflation jacking flip-chip method, the process arrangement is more reasonable, the jacking process is not limited by time, and the construction period can be better guaranteed. The water tank wall group can easily control the opening gap of the wall plates. The inverted lifting and inverted mounting process is stable in lifting, safe, reliable, free of overhead operation and capable of being constructed all day long.

The working principle of the method is that firstly a belt plate at the top of the tank body is welded, a chain block lifting device is installed in the tank, and the structure of the lifting device is shown in figure 4. According to fig. 4, a belt plate 4 to be assembled is arranged below the tank body 3 in the drawing, and then the lifting calculation of the chain block 1 (i.e. chain block) is performed.

Aiming at the selection of the lifting upright post 2:

the design of lifting column 2, specification foundation satisfy the operation requirement, the principle of easy to assemble, 10T calabash joins in marriage DN200 type stand, and its height H is confirmed according to the following formula:

H＝A+L+C+N

in the formula: a- - -cabinet wall maximum (M);

l- - -minimum clear distance is used for the hoisting point of the chain block;

c, taking 500mm according to the actually determined allowance;

n- - -shim tube Φ 426 × 9 height 500 mm.

And (3) configuring the number of the hoisting stand columns:

the number of the lifting upright columns 2 determines the lifting load according to the following three factors: and (4) hoisting the cabinet body above the last layer of wall plate and all additional loads, wherein the calculation formula is Q total ═ K x (Q wall + Q top + Q attached + Q machine).

In the formula: q wall- -weight of the base plate (Kg) excluding the bottom wall plate

Q top-edge-wrapping angle steel and reinforcing angle steel (Kg);

q is attached to-the weight (Kg) of the railing, the sink platform and the accessories;

q machine-construction machine (expanding ring, etc.) weight (Kg);

the K < - > coefficient is 1.2 in consideration of friction resistance, stress unevenness and the like.

The lifting capacity of the hoist and the lifting upright post 2 is determined according to the lifting force P (effective utilization rate of 10t hoist 0.8) and the total lifting weight Qtotal of each machine. The number of machines required for the measurement was 8 in total, that is, n ═ qotal/P ═ 53+1+6+4)/8 in this example.

And (3) calculating the bending strength of the lifting stand column:

bending section modulus Wz ═ pi (D4-D4)/32D of the tube;

in the embodiment, the allowable preferable force σ is Mmax/Wz 123MPa <235MPa, and the material meets the use requirement;

the number of the required machines is determined according to the lifting force P and the total lifting weight Q of each machine, namely n is Q total/P, 12 lifting upright columns are selected according to the lifting weight of the equipment, and the span of adjacent lifting points is about 6.2 m.

The lifting step also includes fabrication and installation of primary and secondary components. Wherein, the design swell is as gas holder equipment shaping's mould, also is used for increasing the hoop rigidity of gas holder wallboard, reduces the hoop deformation that appears when promoting the in-process and girth welding, and the lifting point sets up on the design swell. The shaping expansion ring can be assembled into a 220mm multiplied by 200mm box shape by channel steel, and is connected by 100 multiplied by 8mm flat steel, and the distance is 300 mm. The round rolling is formed into a plurality of square expansion rings which are equally divided into ring sections, and the outer diameter of each square expansion ring is equal to the inner diameter of the wall of the gas cabinet. The connection between the expansion rings can adopt the following steps: the radian of circle section and the laminating of gas holder inner wall, welding expansion ring door shape cardboard realize the laminating of expansion ring and jar inner wall with the tight jack in top, and expansion ring and fixture need have sufficient tension force, will weld 1-2 anti-skidding gusset on the wallboard of every section expansion ring section deep floor department (lug department), and the expansion ring wall lower port is about 250mm from the wallboard bottom.

The lifting step also includes the installation of positioning means such as coaming stops, see fig. 5, where the bottom panel of the tank is below the wall panel 6 to be lifted and the inside of the tank is on the left side of the wall panel to be lifted. When the lifted wallboard 5 is lifted in place, positioning blocks 7 are uniformly welded on the upper opening of the wallboard 6 to be lifted along the circumferential direction in order to facilitate the assembly of the wallboards.

The lifting step further comprises the installation of a tightening device of the positioning device, two symmetrical arrangements are reserved for newly-enclosed wallboards except for the bottommost wallboard, and after the temporarily unwelded movable opening is enclosed, the movable opening is tightened by the tightening device so as to carry out the vertical welding of the assembly circumferential weld and the two movable openings. The upper, middle and lower parts of each movable opening are respectively provided with a pair of adjusting screws with the diameter being more than or equal to M24 (lower back-off) or 2 inverted chains with the diameter being more than or equal to 3 tons for tightening the movable opening, and the movable opening is tightened after the cabinet body is lifted to a preset height.

So set up at hoisting device and accomplish the back, promote the group from top to bottom, after the lower floor's wallboard girth welding was accomplished, demolish the buttress, place the bottom plate with the wallboard on, the group is to wallboard and bottom plate fillet weld and welding, inside and outside fillet weld welding.

On this basis, the mounting step will be further described below.

The installation procedure for the tower section and the bell jar is as follows. The tower section and the bell jar of the gas cabinet are the most important components of the gas cabinet, the installation difficulty is high, and the quality of the tower section and the bell jar is related to whether the gas cabinet can be lifted normally. Firstly, mounting the cushion beams, preferably selecting the upper surfaces of the cushion beams on the same plane, measuring by using a level meter, leveling by using a sizing block until the horizontal deviation is not more than 1mm if the upper surfaces of the cushion beams are uneven, and throwing the suspension loops of the towers onto the upper surfaces of the cushion beams after leveling to serve as the mounting basis of the suspension loops of the towers. And (4) discharging a reference line, namely the circular arc inspection reference line of each tower body, the middle section guide rail and the position line of the inclined ladder on the platform of the water tank. And (3) mounting the prefabricated lower hanging ring along a positioning line of the hanging ring according to the sequence of the prefabricated serial numbers, adjusting the level of the upper opening of the lower hanging ring and the gap of the connector, and then performing positioning welding fixation.

Furthermore, before the hanging ring and the wall plate are integrally welded, anti-deformation temporary supports are preferably additionally arranged between the vertical plate and the wall plate at intervals of 1-1.5m, the vertical deviation of the vertical plate after welding is preferably less than 5mm inwards and 10mm outwards, and the diameter deviation is preferably not more than +/-15 mm.

And after the lower hanging ring is welded, preferably adding water to test leakage, and taking the leakage-proof as qualified. When the upper hanging ring is installed, the upper hanging ring is preferably preassembled on the lower hanging ring and connected by the temporary support, the upper end drilling hole is the same as that of the upper hanging ring, and the lower side drilling hole is the same as that of the lower hanging ring. Furthermore, a supporting member such as a supporting I-steel in the upper hanging ring is installed, the upper plane of the supporting I-steel ensures that the unevenness of the upper surface of the upper hanging ring is less than 10mm after installation, the inward inclination of the hanging ring is not more than 10mm, and the outward inclination is not more than 5mm (measurement and adjustment can be carried out by adopting a theodolite). After welding, the upper suspension loop is preferably lifted to the mounting position (the temporary support is removed) for mounting the upright post and the guide rail.

On the basis of the above, the procedure for the rail mounting is as follows. The guide rail installation mainly controls the straightness and the verticality of the guide rail, the verticality deviation is not more than 7mm after the inner guide rail is installed, the radial deviation is not more than 6mm, the tangential deviation is not more than 7mm, and the contact surface of the guide rail and the guide wheel has no uneven position more than 2 mm; the joint part of the guide rail needs to be polished smoothly, and the distance between the inner part and the outer part of the guide rail needs to be well controlled. Thereby avoiding the phenomenon of guide wheel jamming.

The outer rail must be inspected for straightness before installation, and the allowable deviation of straightness is preferably 1/1000 of the height of the outer rail, and is refurbished when not in compliance. After the outer guide rail is installed, the verticality deviation is not more than 15mm, the radial deviation is not more than 10mm, and the tangential deviation is not more than 15 mm. The contact surface of the outer guide rail and the guide wheel has unevenness which is not more than 2mm, the diameter deviation of the two symmetrical guide rail positions is not more than 10mm, and the chord length deviation between the two adjacent guide rails is not more than 5 mm. When the wall plate is locally concave-convex and the installation of the guide rail can not meet the requirement, the connecting plate between the guide rail and the wall plate can be properly adjusted to ensure that the installation of the guide rail meets the requirement.

Further, the mounting step further comprises an accessory mounting step. Before the guide wheel is installed, the verticality of the inner guide rail and the verticality of the outer guide rail are rechecked, the position of the guide wheel is determined according to the rechecking result, when the upper end of the guide wheel inclines towards the inner side of the guide wheel, a gap equal to the inclination amount is preferably reserved on the contact surface of the lower guide wheel and the guide rail, and otherwise, the lower guide wheel is preferably installed in a manner of being close to the. Before the guide wheel is in place, the guide wheel needs to be cleaned and added with lubricating oil, so that the guide wheel can rotate freely. After the guide wheel base plate is in place and retested to meet the requirements, the guide wheel base plate can be welded. The construction of the platform, ladder, rail, weight rack, etc. of the gas holder is preferably carried out according to the provisions of GB 50205-2001.

Further, the weights are preferably weighed one by one, combined in groups, and two groups of equal weights are symmetrically distributed (the weights are preferably arranged by taking into account the influence of asymmetrically arranged members such as a spiral ladder). The verticality deviation of the air duct in the water tank is not more than 2/1000 of the full height, and a sufficient gap is reserved between the cutting sleeve on the top cover of the bell jar and the vertical pipe so as to ensure the free lifting of the bell jar.

In addition, the following requirements may also be included in the above steps:

the local thinning amount of the surface of the steel plate, the sum of the scratch depth and the actual negative deviation of the steel plate are not more than the standard allowable negative deviation value of the corresponding steel plate.

After the wallboard is rolled, the gap of the wallboard is not more than 4mm by using an inner arc sample plate to check in the horizontal direction and is not more than 2mm by using a straight sample plate to check in the vertical direction.

Prefabricating a top plate: the top plate is preferably arranged according to a determined typesetting drawing, and the arch top plate is inspected by an arc template after being prefabricated and formed, and the gap is not more than 5 mm.

Prefabricating a component: after the arc-shaped members such as edge-wrapping angle iron and the like are processed and formed, the gap is checked by using a sample plate, and the gap is not more than 2 mm. The warping deformation of the component is not more than 0.1% of the length of the component and is not more than 6mm when the component is placed on a platform for inspection.

Assembling the wall plates: the horizontal allowable deviation of the upper opening of the wall plate of the bottom ring is not more than 2mm, and the horizontal deviation of any two points is not more than 6 mm. The sag deviation of the bottom ring wall plate is not more than 3 mm.

After assembly welding, the allowable deviation of the radius of any point of the inner surface at the height of 1m of the bottom ring wall plate is +/-13.

The groove form of the wallboard butt joint is a single-side V-shaped groove, and the butt gap is 2-3 mm.

The misalignment amount of the longitudinal butt joint of the wall plate is not more than 10% of the plate thickness, and the misalignment amount of the circumferential butt joint is not more than 1.5 mm.

After assembly welding, the angular deformation of the welding joint is checked by a 1M sample plate to be not more than 10 mm; the local convex-concave deformation of the wall plate is not more than 13 mm.

Before assembling the bell jar top, the diameter deviation of the edge-covered angle steel is preferably checked to be not more than 15 mm.

The top plate is preferably symmetrically assembled according to a drawn bisector, and the overlap width of the top plate is allowed to deviate by + -5 mm.

The central position deviation of the perforated connecting pipe is not more than 10 mm; the allowable deviation of the extension length of the adapter tube is + -5 mm.

The curvature of the reinforcing plate with the opening is preferably consistent with the curvature of the cabinet body.

The sealing surface of the opening pipe connecting flange is preferably vertical to the axis of the connecting pipe, and the inclination is not more than 1 percent of the outer diameter of the flange and not more than 3 mm.

The ladder railing is preferably manufactured according to the requirements of GB50205-2001 'acceptance Standard for construction quality of Steel Structure engineering', the heights of the welding corners of all lap joint and angle joint welding joints are equal to the thickness of a thinner part except for the height indicated by a drawing, and continuous welding is preferably performed. All pads are preferably vented to 6 and rounded off with an R5 radius.

All welding seams of the gas holder are manufactured by manual electric arc welding (except for butt joint of the connecting pipe and the flange).

The welding process of the tack welding and the clamping apparatus is preferably the same as the formal welding. Both arc initiation and arc quenching are preferably within the groove or over the weld bead. The length of each positioning welding section is not less than 50 mm.

The quality of the initial section and the final section of the welding bead is preferably ensured in the welding process, the backward arc starting method is preferably adopted in the initial section, and an arc striking plate can be adopted if necessary. The termination preferably fills the crater. The interlaminar joints of the multi-layer weld are preferably staggered.

When the wall plate group is paired, the inner surfaces are preferably ensured to be flush, and the misalignment preferably meets the following regulation:

longitudinal weld joint misalignment: when the plate thickness is less than or equal to 10mm during shielded metal arc welding, the plate thickness is not more than 1 mm; when the thickness is more than 10mm, it is not more than 0.1 times and not more than 1.5 mm.

Circumferential weld joint misalignment amount: when the wall plate of the upper ring is smaller than or equal to 8mm during shielded metal arc welding, the misalignment at any point is not larger than 1.0 mm; when the upper ring wall plate is larger than 8mm, the misalignment amount of any point is not larger than 0.2 times of the plate thickness and is not larger than 2 mm.

Before welding, the assembly quality is preferably checked, silt rust, moisture and oil dirt within the range of 20mm on the bevel face and the two sides of the groove are removed, and the welded part is fully dried.

And (4) welding lap welds of which the thickness of the top plate of the bell jar is greater than or equal to 6mm at least twice.

The long welding seams of the medium-width plate are constructed by adopting a sectional back welding or skip welding method, the sectional distance is 400mm, and each welding seam is symmetrically welded from the middle to two end faces by two welders.

When the edge plate is welded, a welding seam close to the 300mm part of the outer edge is welded firstly. And then welding fillet welds at the bottom of the tank and connected with the tank wall, welding the contraction joints between the edge plates and the middle web plate after welding, and preferably finishing the welding of the butt welds of the rest edge plates before welding.

And welding the first layer of the contraction joint of the middle web plate and the edge plate, preferably by adopting a sectional back welding method and a skip welding method.

The fillet weld of the bottom plate and the wall plate is preferably welded after the longitudinal weld of the bottom ring wall plate is welded, and the welding is performed by a plurality of pairs of welders in a segmented manner from the inner side and the outer side of the tank along the same direction. The initial welding bead preferably adopts sectional back welding and skip welding.

The welding sequence of the wall plates is as follows: welding longitudinal welding seams first and then welding circumferential welding seams. After welding the longitudinal welding seams of two adjacent circles of wall plates, welding circumferential welding seams between the two adjacent circles of wall plates; the welders are preferably evenly distributed and weld in the same direction.

The radial long welding line of the top plate adopts a gap symmetrical welding method and is removed from the center to the outside in sections.

When the top plate is welded with the edge-covering angle steel, welders are symmetrically and uniformly distributed and perform sectional back welding along the same direction.

The undercut depth of the butt joint weld is not more than 0.5mm, the length is not more than 10% of the total length of the weld, and the continuous length of each undercut section is preferably less than 100 mm.

The surface residual height of the butt joint welding seam is not more than 0.2 time of the width of the welding seam and then 1mm, and the maximum height is 3 mm.

The depth of the surface depression of the butt joint welding line is not more than 0.5mm, the length of the surface depression is not more than 10% of the total length of the welding line, and the continuous length of each section of depression is less than 100 mm.

The fillet size of the fillet weld preferably conforms to design specifications, when the design is not specified, the fillet height is equal to the thickness of a thinner piece, the fillet weld is preferably in smooth transition in appearance, and the undercut depth is preferably less than or equal to 0.5 mm.

In addition, the construction method of the wet-type helicopter gas holder with the water tank provided by the embodiment further comprises an inspection step. Wherein:

and (3) carrying out vacuum leakage test on the bottom plate, removing impurities and coatings and rust of welding seams in the gas holder before leakage test, and carrying out a tightness test on all welding seams of the bottom plate by adopting a vacuum box method, wherein the test negative pressure value is not lower than 0.053 Mpa.

The butt joint of the water tank wall plate is subjected to local radiographic inspection according to NB/T47013.1-. 6-2015 'nondestructive testing of pressure-bearing equipment', the length of a longitudinal welding joint is 10%, the length of a circumferential welding joint is 5%, the number of T-shaped welding joints is 15%, and the grade III is qualified.

The outer end of each butt-welded joint of the gas holder bottom outer ring plate is preferably subjected to X-ray inspection.

All butt welds of the gas holder wall panel and all welds of the bell jar panel are preferably subjected to kerosene leakage experiments. And carrying out magnetic powder inspection on fillet welds of the bottom plate and the wall plate.

When the weld inspection fails, it is preferable to perform double inspection in the extending direction of the defective portion of the weld welded by the welder, or perform supplementary inspection at other suspicious portions. If the quality is not qualified, the detection of the welding seam welded by the welder is preferably 100%.

Weld repair, repair of various surface defects that occur during construction, preferably meets the following specifications: and (3) scratching, arc scratching, welding scars and other harmful defects with the depth of more than 0.5mm, preferably polishing smoothly and performing magnetic powder detection. The thickness of the polished steel plate is not less than the nominal thickness of the steel plate minus the negative deviation value. When the defect depth or the ground depth exceeds 1mm, repair welding is preferably performed and ground smoothly. The surface defects of the welding seam are preferably ground by using an angle grinder, and if the surface of the welding seam after the defects are ground is lower than that of the base metal, welding repair is preferably carried out. And preferably detecting the embedding depth of the defect before welding and repairing the overproof defect in the welding seam, and determining the removing surface of the defect. The removing length is not less than 50mm, and the removing depth is not more than 2/3 of the plate thickness. The repaired weld joint is preferably subjected to nondestructive testing according to the originally specified method.

In the flush test, after the water tank is manufactured, a water injection foundation settlement test is preferably performed for 48 hours. Before water is filled, whether the fixed welding line is completely shoveled or not is preferably carefully checked, all places which obstruct lifting are preferably treated, sundries in the water tank need to be cleaned up, and one-time observation is carried out before water is filled. Firstly, injecting water to a position 3.5m higher than the water tank for settlement observation and water tank inspection, then, filling water to a position 5m higher than the water tank for settlement observation and water tank water leakage inspection, and finally, filling water to a maximum operation liquid level of 7.16m for basic settlement observation and leakage inspection; after keeping for 48 hours, carrying out settlement observation and leakage inspection; and after acceptance, preventing water and carrying out settlement observation after water drainage. During the water injection test the foundation is observed for sedimentation, if uneven sedimentation is found, the water injection is preferably stopped immediately until the end of sedimentation, after which the water injection can be continued. And (4) preferably checking the wall of the water tank at the same time of water injection, preferably immediately stopping water injection if water leakage is found, reducing the water level to be about 300mm lower than the leakage position for repair welding, and then continuing water injection.

And (4) performing a lifting test, namely performing the lifting test after the water tank test is qualified. The lifting test was carried out with a fan with a flow of 2400m3/h, which delivers air to the gas holder via the inlet duct. The bell jar is slowly lifted, and the contact condition of the guide wheel and the guide rail and the running condition of the guide wheel are preferably observed along the periphery and recorded during the lifting process. The position where the guide rail and the guide wheel are not matched well is uniformly adjusted before the second lifting. During the process of inflating the gas holder, the bell jar is simultaneously subjected to an air tightness test, the welding seams of the wall plates of the bell jar are checked by using soapy water, and after the bell jar is lifted completely, the welding seams of the top plate are preferably checked by using the soapy water, and repair welding is carried out if leakage exists.

And after the gas tightness of the top of the gas holder is checked to be qualified, a valve at the top of the gas holder or a hole cover is opened, the middle section and the bell jar are slowly descended, and the contact condition of the guide wheel and the guide rail is preferably checked and recorded along the periphery in the descending process. After the tightness test of the gas holder is qualified, a rapid lifting test is preferably carried out for 1-2 times, and the lifting speed is not more than 1.5m and not less than 0.4m per minute. If rapid rise cannot be achieved without appropriate gas supply equipment, only a rapid fall test may be performed. The phenomena of no rail clamping, derailment, wall plate deformation, leakage and the like are qualified in the lifting process.

After the gas holder is filled with water through the water tank and the bell jar is airtight and is subjected to rapid lifting test, the following requirements are met, namely the test is qualified: no leakage exists at all welding seams and sealing interfaces; the guide wheels and the guide rails do not have the phenomena of rail clamping, derailment and serious deformation of the wall plate caused by improper installation of the lifting mechanism in the lifting process; each part of the gas holder has no serious deformation; the safety limiting device acts accurately.

According to the construction method of the water tank wet type helicopter gas holder, the components required in the subsequent steps are reasonably prefabricated in the prefabricating and processing step, so that the proper prefabrication allowance is planned to reduce the loss of materials and the assembly difficulty, the number of the components is not too large, and the efficiency of the subsequent steps is improved under the condition that the gas holder meets the requirements; in addition, the prefabrication process prescribes the deviation of the parts in advance, and the parts can always meet the requirements of the gas holder. The assembly step, the lifting step and the installation step are sequentially carried out, so that the assembly efficiency of the gas holder is improved under the condition of ensuring various durability and precision of the gas holder. The detection step is used for detecting the installation layer and the performance layer of the gas holder, so that the assembled gas holder is effectively ensured to meet the construction requirements.

The embodiment also provides a water tank wet type helicopter gas holder, which is obtained by the above construction method of the water tank wet type helicopter gas holder.

The above description is only a preferred embodiment of the present application, and not intended to limit the scope of the present application, and all changes that can be made in the details of the description and drawings, or directly/indirectly implemented in other related technical fields, are intended to be embraced therein without departing from the spirit of the present application.

Claims

1. A construction method of a water tank wet type helicopter gas holder is characterized by comprising the following steps:

2. The method of constructing a sink wet type helicopter case according to claim 1,

in the prefabricating and processing step, under the condition that the curvature radius of the to-be-detected part corresponding to the arc-shaped structural part is smaller than or equal to 12.5m, the chord length under the arc-shaped structural part is not smaller than 1.5 m;

3. The method of constructing a wet helicopter case with a sink according to claim 1, wherein said prefabrication process further comprises:

4. The method of constructing a sink wet type helicopter case according to claim 3,

the difference of diagonal lines, the edge length and the length of the symmetrical line segment of the wall plate respectively have preset deviation;

5. The method of constructing a wet helicopter case with a sink according to claim 1, wherein said prefabrication process further comprises:

6. The method of constructing a wet tank helicopter case according to claim 5, further comprising:

a lifting step of lifting the wall plate for installation;

7. The method of constructing a sink wet type helicopter case according to claim 6,

the guide rail includes an inner guide rail such that a deviation of perpendicularity after the inner guide rail is installed in the installing step is not more than 7mm, and a radial deviation is not more than 6mm and a tangential deviation is not more than 7 mm.

8. The method of constructing a sink wet helicopter case according to claim 6 wherein said step of installing further comprises:

9. The method of constructing a wet tank helicopter case according to claim 1, further comprising:

10. A sink wet-type helicopter gas holder obtained by the method for constructing a sink wet-type helicopter gas holder according to any one of claims 1 to 9.