CN114458050B - Cast house roof protective dismantling method - Google Patents
Cast house roof protective dismantling method Download PDFInfo
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- CN114458050B CN114458050B CN202111592719.5A CN202111592719A CN114458050B CN 114458050 B CN114458050 B CN 114458050B CN 202111592719 A CN202111592719 A CN 202111592719A CN 114458050 B CN114458050 B CN 114458050B
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- roof
- truss
- cast house
- supporting upright
- blast furnace
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- 238000000034 method Methods 0.000 title claims abstract description 40
- 230000001681 protective effect Effects 0.000 title claims abstract description 20
- 238000005520 cutting process Methods 0.000 claims abstract description 7
- 229910000831 Steel Inorganic materials 0.000 claims description 20
- 239000010959 steel Substances 0.000 claims description 20
- 230000003014 reinforcing effect Effects 0.000 claims description 14
- 230000009194 climbing Effects 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 210000001503 joint Anatomy 0.000 claims description 3
- 238000003466 welding Methods 0.000 claims description 3
- 230000002787 reinforcement Effects 0.000 claims 2
- 238000010276 construction Methods 0.000 abstract description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract 2
- 229910052742 iron Inorganic materials 0.000 abstract 1
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G23/00—Working measures on existing buildings
- E04G23/08—Wrecking of buildings
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
Abstract
The invention provides a cast house roof protective dismantling method, which comprises the following steps: prefabricating roof support columns and truss chord supports according to measured operation reference data; the operation reference data comprise the elevation from the truss lower chord of the cast house roof to the upper flange of the overhead travelling crane beam at the side of the blast furnace to be dismantled; the prefabricated roof supporting upright posts and the truss chord supports are installed to temporarily support the cast house roof on the crown block beam; and cutting off the connecting rib plates of the truss and the blast furnace frame column, and carrying out dismantling operation. The invention solves the problem that the dismantling elevation of the blast furnace frame is lower than the elevation of the roof, saves the time for dismantling and reloading the roof of the iron yard, has simple structure, high operation efficiency and short site occupation time, basically does not influence the dismantling operation, saves the mechanical and labor costs and effectively ensures the construction period.
Description
Technical Field
The invention relates to the technical field of blast furnace dismantling, in particular to a cast house roof protective dismantling method.
Background
In the blast furnace rebuilding or overhaul process, it is often necessary to perform a dismantling operation of the furnace body frame, for example, after components are required to be dismantled sequentially from the furnace top to the furnace bottom, the components are assembled sequentially from the furnace bottom to the furnace top in the reverse order; according to the transformation drawing of the blast furnace frame, the old member is supported and reinforced by certain measures, only the part needing reconstruction can be removed, and then the local construction is carried out according to the drawing requirement.
The demolition, the assembly or the reconstruction are all carried out by using a large crane arranged near the blast furnace, so that components which are not required to be demolished or are assembled in place in the working process are protected so as to avoid the damage and maintenance or reworking of the components in the working process, thereby saving the construction period and the hoisting construction cost. At present, the conventional demolition and reloading operation generally adopts a large-sized long-arm crane to decompose the cast house roof into various components to be demolished one by one, and the components are hoisted and recovered in sequence after the newly installed blast furnace body frame is molded. However, in the existing dismantling and protecting operation process, errors in dimension occur in the dismantling and reinstalling process often, and a great deal of labor and mechanical cost is generated in dismantling, transporting and reinstalling, so that the construction period is long.
Disclosure of Invention
In view of the problems, the invention aims to provide a cast house roof protective dismantling method which solves the problems of high cost and long construction period in the existing dismantling and reinstalling process.
According to one aspect of the present invention there is provided a method of protective demolition of a cast house roof, comprising:
prefabricating roof support columns and truss chord supports according to measured operation reference data; the operation reference data comprise the elevation from the truss lower chord of the cast house roof to the upper flange of the overhead travelling crane beam at the side of the blast furnace to be dismantled;
the prefabricated roof supporting upright posts and the truss chord supports are installed to temporarily support the cast house roof on the crown block beam;
and cutting off the connecting rib plates of the truss and the blast furnace frame column, and carrying out dismantling operation.
The method for connecting and reinforcing the crown block beam and the frame column of the blast furnace temporarily comprises the following steps: hanging a chain block above a truss of the cast house to serve as a positioning hoist for supporting a steel column; and temporarily connecting and reinforcing the crown block beam and the frame column of the blast furnace through angle steel.
The method for connecting and reinforcing the crown block beam and the frame column of the blast furnace temporarily comprises the following steps: and removing part of color plates at the joint of the cast house and the blast furnace body frame so as to provide an operation space for later dismantling operation.
The method for connecting and reinforcing the crown block beam and the frame column of the blast furnace temporarily comprises the following steps: and erecting a hanging ladder climbing to the steel column frame beam and the roof truss of the blast furnace and erecting a welding operation platform at the butt joint position.
Wherein, the process of the prefabricated roofing support stand of installation and truss chord support includes: the roof supporting upright post falls from the cast house roof by a crane, is clung to a truss to be supported to be in position, slowly falls down to a hook, and is led to the position right below the roof truss by a pre-hung chain; the perpendicularity of the roof supporting stand is adjusted through chain links preset on two sides of the roof supporting stand; after the roof supporting upright post is determined to be vertically positioned, the top and the bottom of the roof supporting upright post are respectively welded and fixed with the truss and the crown block beam; and installing inter-column truss chords and inter-column struts.
Wherein, the preferable scheme is, before hoisting with the crane roof support stand, still include: the clamping ring is penetrated through binding the roof supporting upright posts or holes are formed in the flange edges of the two sides of the end parts of the roof supporting upright posts, and the lifting hook is aligned with the gravity center of the roof supporting upright posts, so that the roof supporting upright posts are kept in a vertical state after being lifted.
Preferably, the vertical of the roof supporting upright is determined by observing whether the roof supporting upright is vertical or not through a theodolite.
The preferable scheme is that before the top and the bottom of the roof supporting upright post are welded and fixed with the truss and the crown block beam respectively, the method further comprises the following steps: and a gap corresponding to the track of the crown block beam is formed in the position of the column foot web plate of the roof supporting column, and reinforcing rib plates are welded at the two sides of the gap.
Preferably, the reinforcing rib plate and the track are welded and fixed.
Wherein, the preferable scheme is that after the dismantling operation is finished, the method further comprises the following steps: and cutting off the roof supporting upright post, and dismantling the roof supporting upright post by using a chain block matched with a crane.
By utilizing the cast house roof protective dismantling method, the roof system is temporarily supported on the crown block beam through the prefabricated roof support upright post, the blast furnace body frame which needs to be reconstructed can be directly dismantled after the supporting structure is the right, the condition that the dismantling elevation of the blast furnace frame is lower than the elevation of the roof is solved, the time for dismantling and reloading the cast house roof is saved, the structure is simple, the operation efficiency is high, the site occupation time is short, the dismantling operation is basically not influenced, the mechanical and labor cost is saved, and the construction period is effectively ensured.
To the accomplishment of the foregoing and related ends, one or more aspects of the invention comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the invention. These aspects are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Furthermore, the invention is intended to include all such aspects and their equivalents.
Drawings
Other objects and results of the present invention will become more apparent and readily appreciated by reference to the following description and claims in conjunction with the accompanying drawings and a more complete understanding of the invention. In the drawings:
FIG. 1 is a flow chart of a method of protective demolition of a cast house roof according to an embodiment of the invention;
fig. 2 is a schematic structural view of a roof support column and crown block beam according to an embodiment of the invention.
The same reference numerals will be used throughout the drawings to refer to similar or corresponding features or functions.
Detailed Description
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.
Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Fig. 1 shows a flow chart of a method of cast house roof protective demolition according to an embodiment of the invention.
As shown in fig. 1, there is provided a cast house roof protective dismantling method comprising the steps of:
s120: prefabricating roof support columns and truss chord supports according to measured operation reference data; the operation reference data comprise the elevation from the truss lower chord of the cast house roof to the upper flange of the overhead travelling crane beam at the side of the blast furnace to be dismantled;
s140: the prefabricated roof supporting upright posts and the truss chord supports are installed to temporarily support the cast house roof on the crown block beam;
s160: and cutting off the connecting rib plates of the truss and the blast furnace frame column, and carrying out dismantling operation.
The technical scheme of the invention will be described in more detail below with a specific implementation of blast furnace demolition modification using the scheme of the invention.
In the construction process of a blast furnace overhaul project, according to the design drawing of a blast furnace frame designed by a design institute, four main frame columns of a blast furnace body steel frame are not reserved to a 36-meter furnace top large platform according to the original expectation, the external dimensions of a newly-built steel column are changed from 1.2 meters to 1.6 meters due to the enlargement of a furnace body and an upper component, and the whole frame structure is required to be disassembled to 23.2 meters, so that the reserved components are replaced and reinforced correspondingly. The girder upper chord elevation of the cast house roof on the east and west sides is 31.4 meters and is connected with the frame column of the blast furnace body and the frame girder to be dismantled, so that the temporary support transformation of the cast house roof is required to be carried out in advance by the method for ensuring the overhaul construction progress.
In the embodiment, after four 23.2 m bustle pipes hanging girders are planned to be replaced according to design requirements, H200 x 200 steel is used for supporting the lower chord of a roof truss on a cast house crown block girder to form a portal frame structure, and then the truss is cut off to connect rib plates with steel columns to replace and reinforce newly-added steel columns. At the moment, the roof truss is connected with the newly-installed steel frame again, 90% of time for dismantling, cleaning and secondary reinstallation of a conventional roof system is saved in the whole dismantling and transformation process, a large amount of mechanical labor cost is saved, an external dismantling site is not occupied, and the method has good economic applicability in similar dismantling projects.
Specifically, before demolition, the demolition preparation work to be performed is as follows:
1.1, an overhead travelling crane of a thing cast house is driven to the south side of a factory building to cut off a power supply, and the overhead travelling crane is fixed by a chain block.
1.2 cleaning the crown block beam at the side of the blast furnace to be constructed, temporarily connecting and reinforcing the crown block beam with a frame column of the blast furnace by angle steel, and dismantling part of color plates at the joint of a cast house and a frame of the blast furnace body so as to provide an operation space for later dismantling operation.
And 1.3, actually measuring and dismantling protection operation reference data, such as original steel column axis distance, roof truss, crane girder elevation and the like, and manufacturing a roof supporting column according to the elevation from the lower chord of the roof truss to the upper flange of the crane girder.
1.4 building a hanging ladder climbing to the positions of steel column frame beams, roof trusses and the like, building a platform which is convenient to weld at the butt joint position of steel columns installed in a segmented mode, and also utilizing the original platform of the blast furnace, wherein the periphery of the operating platform is provided with simple railings.
1.5 cleaning and checking the original roof structure, and replacing the severely corroded components.
1.6 hanging a pair of 5 ton chain links above the truss, preparing to support the steel column to hoist in place.
And (5) after the dismantling preparation work is finished, prefabricating and installing the roof support upright post and the truss chord support can be performed. Fig. 2 is a schematic structural view of a roof support column and crown block beam according to an embodiment of the invention. As shown in fig. 2, roof support columns are provided between the crown block beams and trusses of the cast house roof to temporarily support the cast house roof on the crown block beams.
Specifically, in the process of installing prefabricated roof support columns and truss chord supports, the following steps can be sequentially performed:
2.1, using a crane to drop the roof supporting upright post from the cast house roof, positioning the roof supporting upright post tightly against a truss to be supported, slowly dropping a hook, and guiding the roof supporting upright post to the position right below the roof truss by using a pre-hung chain;
2.2, adjusting the verticality of the roof supporting stand through chain links preset on two sides of the roof supporting stand; after the roof supporting upright post is determined to be vertically positioned, the top and the bottom of the roof supporting upright post are respectively welded and fixed with the truss and the crown block beam;
2.3 mounting inter-column chords and inter-column struts.
Before the roof supporting upright post is hoisted by the crane, the clamping ring can be penetrated through the binding of the roof supporting upright post or the perforation of the flange openings on two sides of the end part of the roof supporting upright post, and the lifting hook is aligned with the gravity center of the roof supporting upright post, so that the roof supporting upright post is kept in a vertical state after being hoisted.
In adjusting the perpendicularity of the roof support columns, the perpendicularity of the roof support columns can be determined by observing whether the roof support columns are perpendicular or not through theodolites or other feasible instruments.
Before the top and the bottom of the roof supporting upright post are welded and fixed with the truss and the crown block beam respectively, a gap corresponding to a track of the crown block beam can be formed in a column foot web plate position of the roof supporting upright post, and reinforcing rib plates are welded at two sides of the gap; the reinforcing rib plate can be welded and fixed with the rail, and the reinforcing rib plate can be polished and leveled when the reinforcing rib plate is removed.
After the dismantling operation is finished, the modification and the reinstallation of the blast furnace frame can be carried out, and the roof supporting upright post serving as the temporary supporting steel post can be dismantled after the modification and the reinstallation are finished.
In the concrete operation process, before the roof support upright post is dismantled, checking and confirming that the newly-installed and modified member is installed perfectly according to the requirement; connecting the cast house roof truss with the newly-installed frame according to the drawing requirements; finally, cutting open the roof support upright post, and dismantling the roof support upright post by using a chain block matched with a crane.
Before the roof support upright post is used as temporary support, the angle steel is used for temporarily connecting and reinforcing the crown block beam and the frame column of the blast furnace in advance, so that after the roof support upright post is removed, the connecting angle steel between the crown block beam and the frame column of the blast furnace is also required to be removed, and the rail system is restored by retesting.
According to the method for protecting and dismantling the cast house roof, disclosed by the embodiment of the invention, the roof system is temporarily supported on the crown block beam through the prefabricated roof supporting upright post, and the roof supporting upright post can be dismantled directly after dismantling, so that the condition that the dismantling elevation of a blast furnace frame is lower than the elevation of the roof is solved, the time for dismantling and reinstalling the cast house roof is saved, the structure is simple, the operation efficiency is high, the occupied time of a field is short, the dismantling operation is basically not influenced, the mechanical and labor costs are saved, and the construction period is effectively ensured.
The method of protective demolition of a cast house roof according to the invention is described above by way of example with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that various modifications may be made to the cast house roof protective removal method set forth in the foregoing invention without departing from the teachings of the present invention. Accordingly, the scope of the invention should be determined from the following claims.
Claims (8)
1. A method of cast house roof protective demolition comprising:
prefabricating roof support columns and truss chord supports according to measured operation reference data; the operation reference data comprise the elevation from the truss lower chord of the cast house roof to the upper flange of the overhead travelling crane beam at the side of the blast furnace to be dismantled;
hanging a chain block above a truss of the cast house to serve as a positioning hoist for supporting a steel column; the overhead travelling crane beam and the frame column of the blast furnace are temporarily connected and reinforced through angle steel;
the prefabricated roof supporting upright posts and the truss chord supports are installed to temporarily support the cast house roof on the crown block beam; wherein, the process of installing prefabricated roofing support post and truss chord support includes:
the roof supporting upright post falls from the cast house roof by a crane, is clung to a truss to be supported to be in position, slowly falls down to a hook, and is led to the position right below the roof truss by a pre-hung chain;
the perpendicularity of the roof supporting upright post is adjusted through chain blocks preset on two sides of the roof supporting upright post;
after the roof supporting upright post is determined to be vertically positioned, the top and the bottom of the roof supporting upright post are respectively welded and fixed with the truss and the crown block beam;
installing inter-column truss chords and inter-column struts;
and cutting off the connecting rib plates of the truss and the blast furnace frame column, and carrying out dismantling operation.
2. The cast house roof protective demolition method according to claim 1, wherein after the temporary connection reinforcement of the crown block beam with the frame column of the blast furnace, further comprising:
and removing part of color plates at the joint of the cast house and the blast furnace body frame so as to provide an operation space for later dismantling operation.
3. The cast house roof protective demolition method according to claim 2, wherein after the temporary connection reinforcement of the crown block beam with the frame column of the blast furnace, further comprising:
and erecting a hanging ladder climbing to the steel column frame beam and the roof truss of the blast furnace and erecting a welding operation platform at the butt joint position.
4. The cast house roof protective demolition method of claim 1, wherein prior to hoisting the roof support stud with a crane, further comprising:
the clamping ring is penetrated through binding the roof supporting upright posts or holes are formed in the flange edges of the two sides of the end parts of the roof supporting upright posts, and the lifting hook is aligned with the gravity center of the roof supporting upright posts, so that the roof supporting upright posts are kept in a vertical state after being lifted.
5. The cast house roof protective demolition method of claim 1, wherein,
and observing whether the roof supporting upright is vertical or not through a theodolite to determine that the roof supporting upright is vertical.
6. The cast house roof protective removal method of claim 1, wherein prior to welding the top and bottom of the roof support stud to the truss and crown block respectively, further comprising:
and a gap corresponding to the track of the crown block beam is formed in the position of the column foot web plate of the roof supporting column, and reinforcing rib plates are welded at the two sides of the gap.
7. The method of cast house roof protective demolition of claim 6, wherein the reinforcing gusset is welded to the rail.
8. The cast house roof protective demolition method of claim 1, wherein after the demolition operation is completed, further comprising:
and cutting off the roof supporting upright post, and dismantling the roof supporting upright post by using a chain block matched with a crane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111592719.5A CN114458050B (en) | 2021-12-23 | 2021-12-23 | Cast house roof protective dismantling method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111592719.5A CN114458050B (en) | 2021-12-23 | 2021-12-23 | Cast house roof protective dismantling method |
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| Publication Number | Publication Date |
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| CN114458050A CN114458050A (en) | 2022-05-10 |
| CN114458050B true CN114458050B (en) | 2024-04-09 |
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| CN202111592719.5A Active CN114458050B (en) | 2021-12-23 | 2021-12-23 | Cast house roof protective dismantling method |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01168803A (en) * | 1987-12-25 | 1989-07-04 | Kawasaki Steel Corp | Method and device for repairing blast furnace |
| CN101839072A (en) * | 2010-04-09 | 2010-09-22 | 中国第一冶金建设有限责任公司 | Method for replacing column by supporting roof |
| CN101899540A (en) * | 2010-07-29 | 2010-12-01 | 中国一冶集团有限公司 | Construction method for overhauling blast furnace and keeping furnace shell and cooling wall |
| CN201785410U (en) * | 2010-07-29 | 2011-04-06 | 中国一冶集团有限公司 | Furnace shell and cooling wall suspension type retaining device for blast furnace overhaul |
| CN111235333A (en) * | 2020-03-11 | 2020-06-05 | 湖南湘钢工程技术有限公司 | Method for replacing furnace shell of blast furnace body part |
| CN113585828A (en) * | 2020-04-30 | 2021-11-02 | 上海二十冶建设有限公司 | Installation method of large-span inverted triangular pipe truss slope roof workshop |
-
2021
- 2021-12-23 CN CN202111592719.5A patent/CN114458050B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01168803A (en) * | 1987-12-25 | 1989-07-04 | Kawasaki Steel Corp | Method and device for repairing blast furnace |
| CN101839072A (en) * | 2010-04-09 | 2010-09-22 | 中国第一冶金建设有限责任公司 | Method for replacing column by supporting roof |
| CN101899540A (en) * | 2010-07-29 | 2010-12-01 | 中国一冶集团有限公司 | Construction method for overhauling blast furnace and keeping furnace shell and cooling wall |
| CN201785410U (en) * | 2010-07-29 | 2011-04-06 | 中国一冶集团有限公司 | Furnace shell and cooling wall suspension type retaining device for blast furnace overhaul |
| CN111235333A (en) * | 2020-03-11 | 2020-06-05 | 湖南湘钢工程技术有限公司 | Method for replacing furnace shell of blast furnace body part |
| CN113585828A (en) * | 2020-04-30 | 2021-11-02 | 上海二十冶建设有限公司 | Installation method of large-span inverted triangular pipe truss slope roof workshop |
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| CN114458050A (en) | 2022-05-10 |
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