CN117735416A - Combined hoisting method for blast furnace shaft frame - Google Patents
Combined hoisting method for blast furnace shaft frame Download PDFInfo
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- 229910000831 Steel Inorganic materials 0.000 claims description 196
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- 229910000805 Pig iron Inorganic materials 0.000 description 1
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Abstract
The invention discloses a combined hoisting method for a blast furnace body frame, which is characterized in that the whole furnace body frame is assembled on the ground, four upright posts and platform beams of the whole frame are assembled on the ground in a combined manner through the mutual matching of ground manual work and gantry cranes, so that the construction process is greatly simplified, the construction period is greatly shortened, the further quality detection and the accurate positioning of the butt joint of an upper frame and a lower frame are also convenient, the quality and the precision in the construction process can be greatly improved, the installation efficiency of the combined hoisting method for the blast furnace body frame is high, the time and the labor are greatly saved, the safety is good, the risk of the aerial operation is reduced because the whole structure completes most of butt joint and welding work on the ground, and the butt joint position and the welding seam quality are easy to control.
Description
Technical Field
The invention relates to the technical field of blast furnace installation, in particular to a method for combined hoisting of a blast furnace body frame.
Background
The blast furnace is an important device for producing pig iron in metallurgical industry, and mainly consists of a furnace body, a furnace throat, a furnace top, a furnace hearth, a furnace belly, a furnace waist, a furnace bottom and the like. The shaft of the blast furnace is a main body structure of the blast furnace, and various pipes, platforms, ladders, etc. are arranged inside the shaft so as to perform operation and maintenance of the blast furnace. The shaft of the blast furnace generally adopts a steel frame structure and consists of steel columns, steel beams, steel plates and other components. Shaft frame installation of a blast furnace is one of important procedures for blast furnace construction, and the installation quality of the shaft frame installation directly influences the operation efficiency and safety of the blast furnace. At present, a sectional hoisting method is mainly adopted for installing a shaft frame of a blast furnace, namely a steel frame structure is divided into a plurality of sections, the sections are assembled on the ground, and then hoisting and connection are carried out section by section. The traditional blast furnace frame installation method wastes a large amount of machines and time, and has certain potential safety hazards of high-altitude operation.
In the prior art, a combined hoisting method for a blast furnace shaft frame has cases, but has some defects:
1. the utility model provides a publication of publication No. CN101914646A, a novel and jar no bell furnace top charging equipment installation and maintenance device, including furnace top, the furnace top big platform and the weighing bucket of setting outside the furnace top, be equipped with the main frame on the furnace top big platform, the weighing bucket sets up through the hookup crossbeam on the main frame, solved the small frame in furnace top and furnace top charging equipment between the narrow and small main reason that causes furnace top charging equipment maintenance and change difficulty, lead to the equipment maintenance loaded down with trivial details from this, long time, the human input is big, a great deal of problems such as daily inspection maintenance difficulty. However, this mounting method has problems in that: the connecting cross beam used for the furnace top weighing charging bucket is stressed too much, so that the whole structure is unstable;
2. the utility model provides a novel blast furnace body frame, which comprises a lower frame, a lower frame and a lower frame, wherein the lower frame comprises four upright posts, support columns and platform beams, and the platform beams on one side are of a detachable structure; the upper frame is fixed on the lower frame and comprises an upright post and a supporting beam; a furnace top platform frame, on which a furnace top platform annular hanging beam is fixed; the upper frame is also provided with an inclined supporting beam which is fixedly connected with the upright post and the supporting beam; a pure frame structure with a lower frame box section and a frame shear structure with a support. The furnace top platform frame and the furnace top platform ring beam are of a box-shaped cross-section structure. Meets the requirements of a large-scale blast furnace smelting production process and a furnace body rapid installation process, and has the functions of conventional overhaul and short-term overhaul of the blast furnace. On the basis, the technology is advanced, economical, reasonable, safe and applicable. However, this mounting method has problems in that: 1. the high-altitude work load is large, the danger coefficient is high, and 2, the construction period is relatively increased by hoisting for many times;
3. as another disclosure with publication number CN217877098U, an existing blast furnace body frame reconstruction structure with an inter-column support at the upper part comprises an existing furnace body frame, and newly-added steel columns, supports, horizontal steel beams and horizontal stay bars around the existing furnace body frame, wherein the newly-added steel columns are positioned at two sides of the existing furnace body frame column, the newly-added steel support and the horizontal steel beams are used for forming lattice columns with the existing furnace body frame column through the newly-added steel support and the horizontal steel beams between the newly-added steel columns and the floor beams, and the horizontal stay bars are arranged between the newly-added steel columns and the floor beams and are used for connecting the lattice columns and the floor beams into a whole. The method can reserve relatively complete process flow, solves the problem of irregular lateral rigidity of the existing furnace body frame and the irregular upper and lower size of the interlayer shearing bearing capacity, is simple in construction and has good market prospect. However, this mounting method has problems in that: the construction process is comparatively complicated, and the upper structure department steel column supports the construction degree of difficulty higher, has increased holistic steel construction cost simultaneously.
Therefore, how to reduce the potential safety hazard of the overhead operation, improve the construction efficiency, shorten the construction period and correspondingly improve the construction quality becomes the problem to be solved urgently at present, and in view of the problem, a combined hoisting method for the blast furnace body frame is designed.
Disclosure of Invention
The invention aims to provide a combined hoisting method for a blast furnace body frame, which solves the problems of the existing combined hoisting method for the blast furnace body frame in the background technology.
In order to achieve the above purpose, the invention provides a method for hoisting a blast furnace body frame combination, which comprises the following steps:
s1, assembling the ground of a furnace body frame;
s2, hoisting a lower frame of the furnace body;
s3, installing a furnace body platform;
s4, installing a frame at the upper part of the furnace body.
Preferably, in the step S1, the specific step of assembling the ground of the furnace body frame is:
s11: the furnace body frame is divided into a lower frame and an upper frame for assembly, and the furnace body frame needs to be assembled into a whole body by assembling frame columns in the 90-degree direction and 270-degree direction on the ground, and the whole body is hoisted in a combined way;
s12: the method comprises the steps of manufacturing a furnace body steel frame column in a sectional mode at a manufacturing site, arranging a furnace body steel frame column butt joint rapid assembly connecting plate according to the requirements of a deepening diagram at the manufacturing site, mounting the connecting plate on site to carry out steel column butt joint, and assembling the furnace body steel frame column strictly according to the size of the deepening diagram;
s13: assembling the pre-assembled frame beam and steel column on the ground, wherein the frame beam adopts a box beam and H-shaped steel structure, connecting plates at two sides of the box beam and H-shaped steel are mounted on the frame beam in advance through bolts, the bolts cannot be fastened in a loose state at the moment, the connecting plates at one end of the steel column side and the high-strength bolts are mounted after the frame beam and the steel column are connected, and the initial screwing is performed after all the high-strength bolts are completely penetrated into the bolt holes;
s14: after the frame beam is installed, checking and adjusting the assembly size of the frame column, checking the staggered edges of the upper flange plate and the lower flange plate, the connecting plate and the like at the joint of the frame column and the frame beam, and finally screwing the high-strength bolt after confirming no error again after adjustment, wherein the final screwing is constructed strictly according to the installation requirement of the high-strength bolt, so that the installation quality is ensured;
s15: after the high-strength bolts are completely screwed, checking and accepting, closing the manhole after the checking and accepting are qualified, welding the manhole, and then welding the frame beam and the frame column flange plate;
s16: and after the connection part of the frame column and the frame beam is welded, carrying out paint repair coating on the welding part.
Preferably, in the step S2, the specific step of hoisting the lower frame of the furnace body is as follows:
s21: the steel frame used by the lower frame of the furnace body is assembled into an integral structure according to the 90-degree direction and the 270-degree direction, the integral structure after the lower frame of the furnace body is assembled is welded with lifting lugs at bracket positions of frame columns, then the vertical faces of the lifting lugs and the steel columns are welded, four steel wire ropes are selected for lifting, and two steel wire ropes are used as a group to be arranged at the lifting lugs at one side by using a 55tt ring;
s22: retest is carried out on a lower frame column foundation of the furnace body, elevation and axis control lines are arranged on the upper surface of the foundation, a backing plate is arranged according to requirements, and after installation preparation work is finished, the assembled lower frame of the furnace body is lifted and installed by matching with a crawler crane;
s23: firstly, arranging a steel wire rope and a clamping ring of a main adjusting point crawler crane on a lifting lug of a lower frame of a furnace body according to requirements, lifting and shifting a member integrally after the steel wire rope and the clamping ring are fully installed in place, enabling the tail end of a steel column to fall back to the ground, lifting the steel column by using the crawler crane, walking the crawler crane to a lifting position, checking the condition of a main crane, starting to fall to the lower frame of the furnace body after the main crane is free of problems, strictly controlling the falling speed of the main steel column, slowly returning a hook when the main steel column falls into a cup opening, strictly forbidden the steel column to strike a cup opening foundation until the steel column falls into the bottom of the cup opening and is seated on a backing plate, retesting the elevation and the axis of the steel column, adjusting and controlling the perpendicularity of the steel column after the determination is correct, measuring the perpendicularity of the steel column by using a theodolite, keeping the measuring instrument consistent with the axis of the steel column, and controlling the marked axis of the steel column;
s24: after the elevation, the axis and the verticality of the lower frame of the furnace body are confirmed without errors, the periphery of the lower part and the upper part of the cup rim is respectively provided with a stop block for fixing the steel column, so that the elevation and the axis of the steel column are ensured;
s25: the crane slowly returns the hook, rechecks the stability of the lower frame of the furnace body and the welding line at the joint, rechecks the perpendicularity of the lower frame of the furnace body, and can return the hook again to remove the clamping ring and the steel wire rope at the lifting lug after confirming that the error is avoided.
Preferably, in the step S3, the specific step of installing the furnace body platform is as follows:
s31: the platform structure mainly comprises an inner frame platform and an outer frame overhanging platform, wherein the inner frame platform is installed to complete the installation of the platform beams according to the installation sequence of the first main beam and the second main beam, before the installation of the main beam of the platform beam, safety ropes are arranged on the ground to hoist together with components, the outer frame overhanging part of the steel platform is mainly used for completing the assembly work on the ground, then the steel platform is hoisted integrally, and the steel platform is assembled according to the principles of the first main beam and the second main beam in the assembly process;
s32: assembling the platform beam and assembling the lower frame of the furnace body simultaneously, detecting the quality of the welding line according to the drawing requirements, and performing rust removal and paint brushing on the welding line at the joint after meeting the design and specification requirements;
s33: after the welding line paint is processed, laying a platform plate after inspection and acceptance are passed, laying the platform plate from one side to the other side, and arranging special persons to carry out positioning, pressing plates, fixed welding and construction welding on the platform plate after the platform plate is laid.
S34: and after the platform plate is laid, the temporary protection is removed, and the formal edge protection guardrail is installed.
Preferably, in the step S4, the specific step of installing the upper frame of the furnace body is as follows:
s41: after the lower platform and the platform plate are installed, starting to perform installation preparation work of the upper frame, wherein the upper frame and the lower frame are in butt joint connection, and the welding quality grade is the quality of a secondary welding seam grade;
s42: the upper steel frame is assembled on the ground to form an integral structure according to the 90-degree direction and the 270-degree direction, lifting lugs are welded on the upper surface of the frame beam after the frame is assembled, two lateral reinforcing plates are respectively added on two sides of each lifting lug, a crawler crane is selected for hoisting a main crane, 4 steel wire ropes are used for hoisting, and a 55t clamping ring is selected for setting at the lifting lug;
s43: the hoisting of the upper frame is similar to that of the lower frame, and the upper frame and the lower frame are in butt joint connection after hoisting.
Preferably, in step S12, in the manufacturing process of the spliced and butted part, the axis of the coiled pipe is subjected to permanent marking treatment, before pipeline splicing, the marking point on the upper part of the pipeline is retested, after the steel column is butted, the straightness, the offset, the groove size and the spliced size of the steel column are checked, and after the welding of the butt weld is determined, the welding of the butt weld is performed.
Preferably, in step S2, the base size of the lower frame of the furnace body is 4 x 4m, the base of the lower frame of the furnace body adopts a cup mouth base, the depth of the steel column inserted into the cup mouth is 4m, and the size of the cup mouth is 2 x 2m.
Preferably, in step S21, the hoisting steel wire rope is selected from Φ64 (6x37+1) l=20m.
Preferably, in the step S3, when the frame outer overhanging part steel platform is assembled on the ground in principle, the assembling is performed by adopting a flip-chip method, and a temporary steel beam is added on the part steel beam connected with the frame.
Preferably, in step S42, the main hoisting machine uses a working condition of 72m main arm of the crawler crane for hoisting, and the hoisting steel wire rope uses 4 steel wire ropes with phi 64 (6x37+1) l=20m specifications and is used in double.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the furnace body frame integral assembling and hoisting method of the blast furnace body frame, the four stand columns and the platform beams of the integral frame are integrally assembled on the ground through the mutual matching of ground manual work and the gantry crane, so that the construction process is greatly simplified, the construction period is greatly shortened, the further quality detection and the accurate positioning of the butt joint of the upper frame and the lower frame are convenient, and the quality and the precision in the construction process can be greatly improved;
2. according to the furnace body frame integral hoisting method of the blast furnace body frame combination hoisting method, after the integral hoisting is completed through the ground mutual matching and integral assembly, integral hoisting is carried out by a large-tonnage crane, the hoisting times are reduced correspondingly, the construction period is shortened greatly, meanwhile, the supporting steel structure of the stand column is reduced, the integral engineering is optimized, the integral engineering steel structure quantity is reduced, the material cost of the integral engineering is further reduced, and the manual overhead working quantity is reduced correspondingly due to the integral assembly of the ground frame, so that the existing overhead working potential safety hazards are reduced greatly;
3. the method for assembling and hoisting the blast furnace body frame has the advantages of high installation efficiency, time and labor saving, good safety, reduced risk of aerial operation because the whole structure finishes most of butt joint and welding work on the ground, reliable quality because the whole structure finishes most of butt joint and welding work on the ground, and easiness in controlling the butt joint position and welding seam quality.
Drawings
FIG. 1 is a schematic diagram of a flange plate structure of a method for combined hoisting of a blast furnace shaft frame;
FIG. 2 is a schematic diagram of a 270 degree furnace body lower frame structure of the blast furnace body frame combination hoisting method of the present invention;
FIG. 3 is a schematic diagram of a 90-degree furnace body lower frame structure of the blast furnace body frame combination hoisting method of the invention; the method comprises the steps of carrying out a first treatment on the surface of the
FIG. 4 is a schematic diagram of the structure of a connecting plate of the method for assembling and hoisting a blast furnace shaft frame according to the present invention;
FIG. 5 is a schematic diagram showing the connection of a lower 90 DEG furnace body frame and an upper furnace body frame in the combined hoisting method of the blast furnace body frame of the invention;
FIG. 6 is a schematic diagram of the upper frame structure of a 270-degree furnace body of the combined hoisting method of the blast furnace body frame of the invention;
FIG. 7 is a schematic diagram of the upper frame structure of a 90-degree furnace body of the combined hoisting method of the blast furnace body frame of the invention;
FIG. 8 is a top view of a furnace body platform of the blast furnace body frame assembly hoisting method of the present invention;
FIG. 9 is a schematic view of a 270 degree furnace body lower frame lifting in a combined lifting method of a blast furnace body frame of the present invention;
fig. 10 is a schematic view of the combined hoisting method for the blast furnace body frame for hoisting the upper frame of the 270-degree furnace body.
In the figure:
11. a web; 12. flange plates; 13. a connecting plate; 14. a column;
15. a platform beam; 16. a high-strength bolt; 17. a butt joint connection point;
21. inter-column diagonal bracing
3. A crane;
41. an outer overhanging steel platform; 42. lateral reinforcing plates; 43. lifting lugs.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, 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.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific direction, be configured and operated in the specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "provided," "connected," and the like are to be construed broadly, and may be fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Referring to fig. 1-10, the present invention provides a technical solution: the combined hoisting method of the blast furnace body frame comprises the following steps:
s1, assembling the ground of a furnace body frame;
s2, hoisting a lower frame of the furnace body;
s3, installing a furnace body platform;
s4, installing a frame at the upper part of the furnace body.
In the step S1, the specific steps of assembling the ground of the furnace body frame are as follows:
s11: the furnace body frame is divided into a lower frame and an upper frame for assembly, and the furnace body frame needs to be assembled into a whole body by assembling frame columns in the 90-degree direction and 270-degree direction on the ground, and the whole body is hoisted in a combined way;
s12: the method comprises the steps of manufacturing a furnace body steel frame column in a sectional mode at a manufacturing site, arranging a furnace body steel frame column butt joint rapid assembly connecting plate according to the requirements of a deepening diagram at the manufacturing site, mounting the connecting plate on site to carry out steel column butt joint, and assembling the furnace body steel frame column strictly according to the size of the deepening diagram;
s13: assembling the pre-assembled frame beam and steel column on the ground, wherein the frame beam adopts a box beam and H-shaped steel structure, connecting plates at two sides of the box beam and H-shaped steel are mounted on the frame beam in advance through bolts, the bolts cannot be fastened in a loose state at the moment, the connecting plates at one end of the steel column side and the high-strength bolts are mounted after the frame beam and the steel column are connected, and the initial screwing is performed after all the high-strength bolts are completely penetrated into the bolt holes;
s14: after the frame beam is installed, checking and adjusting the assembly size of the frame column, checking the staggered edges of the upper flange plate and the lower flange plate, the connecting plate and the like at the joint of the frame column and the frame beam, and finally screwing the high-strength bolt after confirming no error again after adjustment, wherein the final screwing is constructed strictly according to the installation requirement of the high-strength bolt, so that the installation quality is ensured;
s15: after the high-strength bolts are completely screwed, checking and accepting, closing the manhole after the checking and accepting are qualified, welding the manhole, and then welding the frame beam and the frame column flange plate;
s16: and after the connection part of the frame column and the frame beam is welded, carrying out paint repair coating on the welding part.
Specifically, in the step S13, the bolts cannot be fastened in a loose state so as to facilitate connection between the frame beam and the steel column.
Specifically, through setting up the connecting plate of assembling fast when making the steel column in the preparation place, can improve the assembly efficiency and the precision of steel column, reduce on-the-spot butt joint and welded work load and degree of difficulty.
And S12, in the manufacturing process of the spliced and butted parts, the axis of the coiled pipe is subjected to permanent marking treatment, before the pipeline is spliced, the marking point on the upper part of the pipeline is retested, after the steel column is butted, the straightness, the offset, the groove size and the spliced size of the steel column are checked, and after the accuracy is determined, the butt welding seam is welded. Specifically, the axis of the coiled pipe is subjected to permanent marking treatment in the manufacturing process, so that the control of the on-site assembly angle is facilitated, the pipeline assembly and the butt joint can be conveniently carried out, the correctness and the consistency of the pipeline are ensured, and the marking point on the upper part of the pipeline is required to be retested before the pipeline assembly is carried out, so that the assembly size of the pipeline is ensured.
In the step S2, the specific step of hoisting the lower frame of the furnace body is as follows:
s21: the steel frame used by the lower frame of the furnace body is assembled into an integral structure according to the 90-degree direction and the 270-degree direction, the integral structure after the lower frame of the furnace body is assembled is welded with lifting lugs at bracket positions of frame columns, then the vertical faces of the lifting lugs and the steel columns are welded, four steel wire ropes are selected for lifting, and two steel wire ropes are used as a group to be arranged at the lifting lugs at one side by using a 55tt ring;
s22: retest is carried out on a lower frame column foundation of the furnace body, elevation and axis control lines are arranged on the upper surface of the foundation, a backing plate is arranged according to requirements, and after installation preparation work is finished, the assembled lower frame of the furnace body is lifted and installed by matching with a crawler crane;
s23: firstly, arranging a steel wire rope and a clamping ring of a main adjusting point crawler crane on a lifting lug of a lower frame of a furnace body according to requirements, lifting and shifting a member integrally after the steel wire rope and the clamping ring are fully installed in place, enabling the tail end of a steel column to fall back to the ground, lifting the steel column by using the crawler crane, walking the crawler crane to a lifting position, checking the condition of a main crane, starting to fall to the lower frame of the furnace body after the main crane is free of problems, strictly controlling the falling speed of the main steel column, slowly returning a hook when the main steel column falls into a cup opening, strictly forbidden the steel column to strike a cup opening foundation until the steel column falls into the bottom of the cup opening and is seated on a backing plate, retesting the elevation and the axis of the steel column, adjusting and controlling the perpendicularity of the steel column after the determination is correct, measuring the perpendicularity of the steel column by using a theodolite, keeping the measuring instrument consistent with the axis of the steel column, and controlling the marked axis of the steel column;
s24: after the elevation, the axis and the verticality of the lower frame of the furnace body are confirmed without errors, the periphery of the lower part and the upper part of the cup rim is respectively provided with a stop block for fixing the steel column, so that the elevation and the axis of the steel column are ensured;
s25: the crane slowly returns the hook, rechecks the stability of the lower frame of the furnace body and the welding line at the joint, rechecks the perpendicularity of the lower frame of the furnace body, and can return the hook again to remove the clamping ring and the steel wire rope at the lifting lug after confirming that the error is avoided.
Specifically, by adopting the cup rim foundation for the lower frame foundation of the furnace body, the stability and shock resistance of the steel column can be increased, and the steel column is prevented from tilting or shifting in the hoisting and running processes.
In the step S2, the basic size of the lower frame of the furnace body is 4 x 4m, the basic of the lower frame of the furnace body adopts a cup mouth foundation, the depth of a steel column inserted into the cup mouth is 4m, and the size of the cup mouth is 2 x 2m. Specifically, through confirming furnace body lower part frame basic size and rim of a cup size, can carry out reasonable matching according to the scale and the design requirement of blast furnace, guarantee the adaptability of furnace body frame and basis.
In step S21, the hoisting wire rope is selected from Φ64 (6×37+1) l=20m. Specifically, by selecting a steel wire rope for hoisting with a proper specification, the safety and the reliability in the hoisting process can be ensured, and accidents such as breakage or sliding of the steel wire rope can be avoided.
In step S22, the elevation and axis of the steel column are ensured. Ensures the verticality and the safety stability of the lower frame of the furnace body.
In the step S3, the specific steps of installing the furnace body platform are as follows:
s31: the platform structure mainly comprises an inner frame platform and an outer frame overhanging platform, wherein the inner frame platform is installed to complete the installation of the platform beams according to the installation sequence of the first main beam and the second main beam, before the installation of the main beam of the platform beam, safety ropes are arranged on the ground to hoist together with components, the outer frame overhanging part of the steel platform is mainly used for completing the assembly work on the ground, then the steel platform is hoisted integrally, and the steel platform is assembled according to the principles of the first main beam and the second main beam in the assembly process;
s32: assembling the platform beam and assembling the lower frame of the furnace body simultaneously, detecting the quality of the welding line according to the drawing requirements, and performing rust removal and paint brushing on the welding line at the joint after meeting the design and specification requirements;
s33: after the welding line paint is processed, laying a platform plate after inspection and acceptance are passed, laying the platform plate from one side to the other side, and arranging special persons to carry out positioning, pressing plates, fixed welding and construction welding on the platform plate after the platform plate is laid.
S34: and after the platform plate is laid, the temporary protection is removed, and the formal edge protection guardrail is installed.
Specifically, the platform structure is divided into the frame inner platform and the frame outer cantilever platform, so that the space can be reasonably utilized, the using area and the functions of the platform are increased, and the operation and the maintenance of the blast furnace are facilitated.
In the S31 step, the safety rope is required to be arranged on the ground before the installation of the main girder of the platform girder to be hoisted together with the components, so that structural installation personnel can conveniently hang the safety belt when moving on the main girder in the process of installing the secondary girder.
In the step S33, the platform plate is laid from one side to the other side, so that the operation of constructors and the construction safety are facilitated.
And S34, installing the formal temporary edge protection guardrail after removing the temporary protection, so as to ensure the safety protection of constructors.
And S3, when the frame overhanging part of the steel platform is assembled on the ground in principle, the frame is assembled by adopting a flip-chip method, and a temporary steel beam is added on the part of the steel beam connected with the frame. Specifically, the inversion method is adopted when the frame is assembled on the ground and the part of steel platform is overhanging, and the temporary steel girder is added on the part of steel girder connected with the frame, so that the risk and difficulty of aerial operation can be reduced, the assembling quality and efficiency are improved, and the integral strength of the overhanging platform is ensured.
In the step S4, the concrete steps of installing the upper frame of the furnace body are as follows:
s41: after the lower platform and the platform plate are installed, starting to perform installation preparation work of the upper frame, wherein the upper frame and the lower frame are in butt joint connection, and the welding quality grade is the quality of a secondary welding seam grade;
s42: the upper steel frame is assembled on the ground to form an integral structure according to the 90-degree direction and the 270-degree direction, lifting lugs are welded on the upper surface of the frame beam after the frame is assembled, two lateral reinforcing plates are respectively added on two sides of each lifting lug, a crawler crane is selected for hoisting a main crane, 4 steel wire ropes are used for hoisting, and a 55t clamping ring is selected for setting at the lifting lug;
s43: the hoisting of the upper frame is similar to that of the lower frame, and the upper frame and the lower frame are in butt joint connection after hoisting.
Specifically, the upper frame and the lower frame are connected in a butt joint mode, so that the strength and the rigidity of connection can be improved, and the overall performance of the furnace body frame is guaranteed.
In the step S42, the main hoisting machine is hoisted under the working condition of 72m main arms of the crawler crane, and 4 steel wire ropes with phi 64 (6 x 37+1) L=20m specifications are used in parallel. Specifically, the crawler crane with proper working conditions is selected for hoisting the upper frame, and the steel wire rope with proper specifications is selected for hoisting, so that the safety and reliability of the upper frame in the hoisting process can be ensured, and accidents such as overload or instability of the crawler crane can be avoided.
Specifically, web 11 is equipped with at the inboard middle part of flange plate 12, and furnace body lower part frame includes four stands 14 and a set of platform roof beam 15, and furnace body upper part frame includes four stands 14 and a set of crane roof beam, and the junction of furnace body upper part frame and furnace body lower part frame is butt joint tie point 17, and the furnace body upper part frame inboard is equipped with the post bearing diagonal 21 and guarantees overall structure's stability.
Example 1
Referring to the accompanying drawings 1-10 of the specification, a concrete implementation process of a blast furnace body frame combined hoisting method mainly comprises the following steps:
s1, assembling furnace body frame ground
S11: the furnace body frame is divided into a lower frame and an upper frame for assembly, and the furnace body frame needs to be assembled into a whole body by assembling frame columns in the 90-degree direction and 270-degree direction on the ground, and the whole body is hoisted in a combined way;
s12: the method comprises the steps of manufacturing a furnace body steel frame column in a sectional mode at a manufacturing site, arranging a furnace body steel frame column butt joint rapid assembly connecting plate according to the requirements of a deepening diagram at the manufacturing site, manufacturing a Q345B steel plate by the connecting plate, mounting the connecting plate on site to carry out steel column butt joint, and assembling the furnace body steel frame column according to the sizes of the deepening diagram;
s13: assembling the pre-assembled frame beam and steel column on the ground, wherein the frame beam adopts a box beam and H-shaped steel structure, connecting plates at two sides of the box beam and H-shaped steel are mounted on the frame beam in advance through bolts, the bolts cannot be fastened in a loose state at the moment, the connecting plates at one end of the steel column side and the high-strength bolts are mounted after the frame beam and the steel column are connected, the high-strength bolts adopt M36 specifications, and the initial screwing is performed after all the high-strength bolts are penetrated into the bolt holes;
s14: after the frame beam is installed, checking and adjusting the assembly size of the frame column, checking the staggered edges of the upper flange plate and the lower flange plate, the connecting plate and the like at the joint of the frame column and the frame beam, and finally screwing the high-strength bolt after confirming no error again after adjustment, wherein the final screwing is constructed strictly according to the installation requirement of the high-strength bolt, so that the installation quality is ensured;
s15: after the high-strength bolts are completely screwed, checking and accepting, closing the manhole after the checking and accepting are qualified, welding the manhole, and then welding the frame beam and the frame column flange plate;
s16: and after the connection part of the frame column and the frame beam is welded, carrying out paint repair coating on the welding part.
S2, hoisting the lower frame of the furnace body
S21: the basic size of a lower frame of the furnace body is 4 x 4m, the basic is a cup foundation, the depth of a steel column inserted into a cup is 4m, the size of the cup is 2 x 2m, steel frames used for the lower frame of the furnace body are assembled into an integral structure according to the 90-degree direction and the 270-degree direction, the combined weight of the steel frames is 90.001t, the single weight of box frame beams in the 0-degree direction and the 180-degree direction is 18.673t, lifting lugs are welded at brackets of the frame columns in the integral structure after the lower frame of the furnace body is assembled, the size of each lifting lug is 300 x 280 x 50mm, then the elevation of each lifting lug is welded with the steel column, four steel wire ropes are selected for lifting, phi 64 (6 x 37+1) L=20m specifications are selected for lifting, and the two steel wire ropes are arranged at one side of the lifting lug by using a 55tt ring as a group;
s22: retest is carried out on a lower frame column foundation of the furnace body, elevation and axis control lines are arranged on the upper surface of the foundation, a backing plate is arranged according to requirements, and after installation preparation work is finished, the assembled lower frame of the furnace body is lifted and installed by matching with a crawler crane;
s23: firstly, arranging a steel wire rope and a clamping ring of a main adjusting point crawler crane on a lifting lug of a lower frame of a furnace body according to requirements, lifting and shifting a member integrally after the steel wire rope and the clamping ring are fully installed in place, enabling the tail end of a steel column to fall back to the ground, lifting the steel column by using the crawler crane, walking the crawler crane to a lifting position, checking the condition of a main crane, starting to fall to the lower frame of the furnace body after the main crane is free of problems, strictly controlling the falling speed of the main steel column, slowly returning a hook when the main steel column falls into a cup opening, strictly forbidden the steel column to strike a cup opening foundation until the steel column falls into the bottom of the cup opening and is seated on a backing plate, retesting the elevation and the axis of the steel column, adjusting and controlling the perpendicularity of the steel column after the determination is correct, measuring the perpendicularity of the steel column by using a theodolite, keeping the measuring instrument consistent with the axis of the steel column, and controlling the marked axis of the steel column;
s24: after the elevation, the axis and the verticality of the lower frame of the furnace body are confirmed without errors, the periphery of the lower part and the upper part of the cup rim is respectively provided with a stop block for fixing the steel column, so that the elevation and the axis of the steel column are ensured;
s25: the crane slowly returns the hook, rechecks the stability of the lower frame of the furnace body and the welding line at the joint, rechecks the perpendicularity of the lower frame of the furnace body, and can return the hook again to remove the clamping ring and the steel wire rope at the lifting lug after confirming that the error is avoided.
S3, installing a furnace body platform:
s31: the platform structure mainly comprises an inner frame platform and an outer frame overhanging platform, wherein the inner frame platform is installed to complete the installation of the platform beams according to the installation sequence of the first main beam and the second main beam, before the installation of the main beam of the platform beam, safety ropes are arranged on the ground to hoist together with components, the outer frame overhanging part of the steel platform is mainly used for completing the assembly work on the ground, then the steel platform is hoisted integrally, and the steel platform is assembled according to the principles of the first main beam and the second main beam in the assembly process;
s32: assembling the platform beam and assembling the lower frame of the furnace body simultaneously, detecting the quality of the welding line according to the drawing requirements, and performing rust removal and paint brushing on the welding line at the joint after meeting the design and specification requirements;
s33: after the welding line paint is processed, laying a platform plate after inspection and acceptance are passed, laying the platform plate from one side to the other side, and arranging special persons to carry out positioning, pressing plates, fixed welding and construction welding on the platform plate after the platform plate is laid.
S34: and after the platform plate is laid, the temporary protection is removed, and the formal edge protection guardrail is installed.
S4, mounting a furnace body upper frame:
s41: after the lower platform and the platform plate are installed, starting to perform installation preparation work of the upper frame, wherein the upper frame and the lower frame are in butt joint connection, and the welding quality grade is the quality of a secondary welding seam grade;
s42: the upper steel frame is assembled into an integral structure on the ground according to the 90-degree direction and the 270-degree direction, the weight of the steel frame is 82.180t, lifting lugs are welded on the upper surface of a frame beam after the frame is assembled, the sizes of the lifting lugs are 300 x 250 x 40mm, two lateral reinforcing plates are respectively added on two sides of each lifting lug, a crawler crane is selected for lifting a main crane, a main arm working condition of the crawler crane 72m is selected for lifting the main crane, 4 steel wire ropes with the specification of phi 64 (6 x 37+1) L=20m are selected for double use, 4 steel wire ropes are adopted for double use, and a 55t clamping ring is selected for setting at the lifting lugs;
s43: the hoisting of the upper frame is similar to that of the lower frame, and the upper frame and the lower frame are in butt joint connection after hoisting.
The blast furnace body frame combined hoisting method of the embodiment achieves good effect in practical application.
Although the present invention has been described with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements and changes may be made without departing from the spirit and principles of the present invention.
Claims (7)
1. The combined hoisting method for the blast furnace body frame is characterized by comprising the following steps of:
s1, assembling the ground of a furnace body frame, wherein the assembling comprises the steps of assembling the furnace body frame in a segmented manner, manufacturing a furnace body steel frame column, assembling a frame beam and a steel column in a combined manner, rechecking, adjusting and checking, welding treatment and paint repair coating;
s2, hoisting a lower frame of the furnace body, wherein the hoisting comprises welding lifting lugs, hoisting installation, setting a stop block, rechecking and dismantling in sequence;
s3, installing a furnace body platform, wherein the furnace body platform sequentially comprises platform beam installation, platform beam assembly, platform plate laying and edge protection guardrail rod installation;
s4, installing an upper frame of the furnace body, wherein the upper frame is in butt joint, welding lifting lugs, lifting and butt joint.
2. The method for hoisting a blast furnace shaft frame assembly according to claim 1, wherein,
in the step S1, the concrete steps of assembling the ground of the furnace body frame are as follows:
s11: the furnace body frame is divided into a lower frame and an upper frame for assembly, and the furnace body frame needs to be assembled into a whole body by assembling frame columns in the 90-degree direction and 270-degree direction on the ground, and the whole body is hoisted in a combined way;
s12: the method comprises the steps of manufacturing a furnace body steel frame column in a sectional mode at a manufacturing site, arranging a furnace body steel frame column butt joint rapid assembly connecting plate according to the requirements of a deepening diagram at the manufacturing site, mounting the connecting plate on site to carry out steel column butt joint, and assembling the furnace body steel frame column strictly according to the size of the deepening diagram;
s13: assembling the pre-assembled frame beam and steel column on the ground, wherein the frame beam adopts a box beam and H-shaped steel structure, connecting plates at two sides of the box beam and H-shaped steel are mounted on the frame beam in advance through bolts, the bolts cannot be fastened in a loose state at the moment, the connecting plates at one end of the steel column side and the high-strength bolts are mounted after the frame beam and the steel column are connected, and the initial screwing is performed after all the high-strength bolts are completely penetrated into the bolt holes;
s14: after the frame beam is installed, checking and adjusting the assembly size of the frame column, checking the staggered edges of the upper flange plate and the lower flange plate, the connecting plate and the like at the joint of the frame column and the frame beam, and finally screwing the high-strength bolt after confirming no error again after adjustment, wherein the final screwing is constructed strictly according to the installation requirement of the high-strength bolt, so that the installation quality is ensured;
s15: after the high-strength bolts are completely screwed, checking and accepting, closing the manhole after the checking and accepting are qualified, welding the manhole, and then welding the frame beam and the frame column flange plate;
s16: and after the connection part of the frame column and the frame beam is welded, carrying out paint repair coating on the welding part.
3. The method for hoisting a blast furnace shaft frame assembly according to claim 1, wherein,
in the step S2, the specific step of hoisting the lower frame of the furnace body is as follows:
s21: the steel frame used by the lower frame of the furnace body is assembled into an integral structure according to the 90-degree direction and the 270-degree direction, the integral structure after the lower frame of the furnace body is assembled is welded with lifting lugs at bracket positions of frame columns, then the vertical faces of the lifting lugs and the steel columns are welded, four steel wire ropes are selected for lifting, and two steel wire ropes are used as a group to be arranged at the lifting lugs at one side by using a 55tt ring;
s22: retest is carried out on a lower frame column foundation of the furnace body, elevation and axis control lines are arranged on the upper surface of the foundation, a backing plate is arranged according to requirements, and after installation preparation work is finished, the assembled lower frame of the furnace body is lifted and installed by matching with a crawler crane;
s23: firstly, arranging a steel wire rope and a clamping ring of a main adjusting point crawler crane on a lifting lug of a lower frame of a furnace body according to requirements, lifting and shifting a member integrally after the steel wire rope and the clamping ring are fully installed in place, enabling the tail end of a steel column to fall back to the ground, lifting the steel column by using the crawler crane, walking the crawler crane to a lifting position, checking the condition of a main crane, starting to fall to the lower frame of the furnace body after the main crane is free of problems, strictly controlling the falling speed of the main steel column, slowly returning a hook when the main steel column falls into a cup opening, strictly forbidden the steel column to strike a cup opening foundation until the steel column falls into the bottom of the cup opening and is seated on a backing plate, retesting the elevation and the axis of the steel column, adjusting and controlling the perpendicularity of the steel column after the determination is correct, measuring the perpendicularity of the steel column by using a theodolite, keeping the measuring instrument consistent with the axis of the steel column, and controlling the marked axis of the steel column;
s24: after the elevation, the axis and the verticality of the lower frame of the furnace body are confirmed without errors, the periphery of the lower part and the upper part of the cup rim is respectively provided with a stop block for fixing the steel column, so that the elevation and the axis of the steel column are ensured;
s25: the crane slowly returns the hook, rechecks the stability of the lower frame of the furnace body and the welding line at the joint, rechecks the perpendicularity of the lower frame of the furnace body, and can return the hook again to remove the clamping ring and the steel wire rope at the lifting lug after confirming that the error is avoided.
4. The method for hoisting a blast furnace shaft frame assembly according to claim 1, wherein,
in the step S3, the specific steps of installing the furnace body platform are as follows:
s31: the platform structure mainly comprises an inner frame platform and an outer frame overhanging platform, wherein the inner frame platform is installed to complete the installation of the platform beams according to the installation sequence of the first main beam and the second main beam, before the installation of the main beam of the platform beam, safety ropes are arranged on the ground to hoist together with components, the outer frame overhanging part of the steel platform is mainly used for completing the assembly work on the ground, then the steel platform is hoisted integrally, and the steel platform is assembled according to the principles of the first main beam and the second main beam in the assembly process;
s32: assembling the platform beam and assembling the lower frame of the furnace body simultaneously, detecting the quality of the welding line according to the drawing requirements, and performing rust removal and paint brushing on the welding line at the joint after meeting the design and specification requirements;
s33: after the welding line paint is processed, laying a platform plate after inspection and acceptance are passed, laying the platform plate from one side to the other side, and arranging special persons to carry out positioning, pressing plates, fixed welding and construction welding on the platform plate after the platform plate is laid.
S34: and after the platform plate is laid, the temporary protection is removed, and the formal edge protection guardrail is installed.
5. The method for hoisting a blast furnace shaft frame assembly according to claim 1, wherein,
in the step S4, the concrete steps of installing the upper frame of the furnace body are as follows:
s41: after the lower platform and the platform plate are installed, starting to perform installation preparation work of the upper frame, wherein the upper frame and the lower frame are in butt joint connection, and the welding quality grade is the quality of a secondary welding seam grade;
s42: the upper steel frame is assembled on the ground to form an integral structure according to the 90-degree direction and the 270-degree direction, lifting lugs are welded on the upper surface of the frame beam after the frame is assembled, two lateral reinforcing plates are respectively added on two sides of each lifting lug, a crawler crane is selected for hoisting a main crane, 4 steel wire ropes are used for hoisting, and a 55t clamping ring is selected for setting at the lifting lug;
s43: the hoisting of the upper frame is similar to that of the lower frame, and the upper frame and the lower frame are in butt joint connection after hoisting.
6. The method for hoisting the blast furnace shaft frame assembly according to claim 2, wherein,
and S12, in the manufacturing process of the spliced and butted parts, the axis of the coiled pipe is subjected to permanent marking treatment, before the pipeline is spliced, the marking point on the upper part of the pipeline is retested, after the steel column is butted, the straightness, the offset, the groove size and the spliced size of the steel column are checked, and after the accuracy is determined, the butt welding seam is welded.
7. A method for hoisting a blast furnace shaft frame assembly according to claim 3, wherein,
and S3, when the frame outer overhanging part steel platform is assembled on the ground in principle, the frame outer overhanging part steel platform is assembled by adopting a flip-chip method, and a temporary steel beam is added on a part of steel beam connected with the frame.
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