CN105890342B - The restorative procedure for losing arc furnace cover is burnt in a kind of etch - Google Patents
The restorative procedure for losing arc furnace cover is burnt in a kind of etch Download PDFInfo
- Publication number
- CN105890342B CN105890342B CN201610227407.7A CN201610227407A CN105890342B CN 105890342 B CN105890342 B CN 105890342B CN 201610227407 A CN201610227407 A CN 201610227407A CN 105890342 B CN105890342 B CN 105890342B
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- CN
- China
- Prior art keywords
- remaining
- arc furnace
- furnace cover
- steel structure
- skirtboard
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
- F27B3/12—Working chambers or casings; Supports therefor
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D1/00—Casings; Linings; Walls; Roofs
- F27D1/18—Door frames; Doors, lids, removable covers
- F27D1/1808—Removable covers
- F27D1/1816—Removable covers specially adapted for arc furnaces
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Furnace Housings, Linings, Walls, And Ceilings (AREA)
Abstract
The restorative procedure for losing arc furnace cover is burnt the invention discloses a kind of etch.This method, including step in detail below：Step S1, arc furnace cover handling；Step S2, remaining steel structure separation；Step S3, drawing is repaired in design；Step S4, Repair gene；Step S5, moulding by casting.The method of the present invention linking is orderly, process is simple and efficient, adequately utilize arc furnace cover remaining steel structure, resource is saved, enhancing bar and dowel are additionally arranged on steel structure simultaneously, so that the performance of arc furnace cover significantly improves, the arc furnace cover of same castable cast, repair steel structure increases by 40 times or so than new steel structure service life；Similar access times are offline, and the anti-etch of arc furnace cover and the antistrip performance for repairing the cast of steel structure are significantly better than new steel structure.
Description
Technical field
The reparation side for losing arc furnace cover is burnt the invention belongs to electric-arc furnace steelmaking equipment technical field more particularly to a kind of etch
Method.
Background technology
Electric arc furnaces is the important equipment for producing special steel and high-alloy steel, and electric arc furnaces includes arc furnace cover, in arc furnace cover
Be fitted with graphite electrode, by graphite electrode into electric arc furnaces inputing power, the electric arc occurred between electrode tip and furnace charge
It is made steel for heat source.The arc furnace cover used at present includes steel structure and castable, and steel structure includes round bearing plate and skirtboard, circle
It is circumferentially all provided on the upside of shape bearing plate there are three lifting lug, lower side ring sets skirtboard, the intracavitary filling that skirtboard and round bearing plate are formed
Castable simultaneously forms entirety, is equipped with graphite electrode hole at whole middle part, graphite electrode is inserted into electrode hole.Dead electricity is burnt in etch
The restorative procedure of arc bell in use, due to by high temperature, rapid heat cycle effect and molten steel slag continuous etch, electricity
The downside working lining of arc bell is constantly etched, and thickness is constantly thinned, until after skirtboard exposes, etch is burnt stall degree and added
Soon, when arc furnace cover etch to a certain extent after, need replacing new arc furnace cover, and with rear arc furnace cover then directly as work
Industry rubbish discard processing, on the one hand, environmental pollution can be caused with rear arc furnace cover, on the other hand, with the steel structure of rear arc furnace cover
Partial round bearing plate is still excellent, and the waste of resource is caused after abandoning, is unfavorable for enterprise's cost efficiency.Based on upper
The presence of problem is stated, how etch to be burnt and is reused after losing arc furnace cover reparation, be that a great problem to be solved is badly in need of in enterprise.
Invention content
The defects of in order to overcome the prior art, burns the reparation side for losing arc furnace cover the object of the present invention is to provide a kind of etch
Method carries out recycling reparation to arc furnace cover steel structure, and realization recycles, and reduces steel structure processing cost；Repair steel structure with it is identical
Castable is poured into a mould again, improves arc furnace cover performance and lid age；Reduce industrial refuse discharge and pollution, improve enterprise and
Social benefit.
In order to realize above-mentioned goal of the invention, the present invention uses following technical scheme：
The restorative procedure for losing arc furnace cover is burnt in a kind of etch, including step in detail below：
Step S1, arc furnace cover handling
It will use the arc furnace covers of guideline lives from electric arc furnaces by under crane or traveling crane, being hoisted to designated treatment and showing
；
Step S2, remaining steel structure separation
Using special equipment and tool, to being detached with the remaining castable refractory in rear arc furnace cover with remaining steel structure,
In separation process, the deformation that strength generates the round bearing plate and lifting lug of remaining steel structure and remaining skirtboard should be protected as possible
It holds in prescribed limit；
Step S3, drawing is repaired in design
1) height of remaining skirtboard, is measured；
2), according to the height of remaining skirtboard, the diameter of round bearing plate and load-bearing requirements setting enhancing bar and dowel, increase
The lower end of strong bar is no more than plane where former skirtboard lower end；
Step S4, Repair gene
1), between the round bearing plate to remaining steel structure and lifting lug, round bearing plate and remaining skirtboard junction, intensity is not
Enough, injury region carries out repair welding by welding conditions requirement；
2) cleaning polishing, is carried out to the lower part of remaining skirtboard and round bearing plate, grinds off remaining skirtboard and round bearing plate
Remaining castable on lower part, then the bar of welding enhancing by drawing, enhances bar firm welding；
3), after all enhancing bars have welded, then by drawing around enhancing bar welding twice dowel；
4) verification inspection processing, is carried out as required to the remaining steel structure after reparation, it is qualified to examine, after meeting the requirements, storage
It is for use at drying；
Step S5, moulding by casting
Remaining steel structure after qualified repair is put into arc furnace cover mold, is corrected to specified position, positioning is fixed, and use is resistance to
Fiery castable pours into a mould vibration moulding.
Further, it is further included before above-mentioned steps S4：Step S6, shape corrects
The shape deformation of round bearing plate and lifting lug to remaining steel structure and remaining skirtboard go beyond the scope or deform it is serious,
Equipment and tool should be used to be corrected processing, round load-bearing plate flatness reaches ± 15mm；Deviation reaches on the outside of remaining skirtboard
±20mm。
Further, in the restorative procedure for losing arc furnace cover is burnt in above-mentioned etch, above-mentioned enhancing bar, dowel are by screw thread
Steel is made.
Further, in the restorative procedure for losing arc furnace cover is burnt in above-mentioned etch, above-mentioned twice dowel is arranged in parallel, point
Not with enhancing bar welding, the intensity of steel structure is enhanced.
Further, in the restorative procedure for losing arc furnace cover is burnt in above-mentioned etch, above-mentioned enhancing bar takes the shape of the letter U or V-arrangement or circle
Arc, it is best to select U-shaped enhancing bar.
Compared with prior art, the advantageous effect that the present invention can realize includes at least the following aspects：
(1) the method for the present invention linking is orderly, and process is simple and efficient, adequately using arc furnace cover remaining steel structure, saves
Resource, while enhancing bar and dowel are additionally arranged on steel structure so that the performance of arc furnace cover significantly improves, and similarly pours
The arc furnace cover of material feeding cast, repair steel structure increases by 40 times or so than new steel structure service life；Similar access times are offline,
The anti-etch of arc furnace cover and the antistrip performance for repairing the cast of steel structure are significantly better than new steel structure；
(2) present invention is effectively reduced arc furnace cover processing cost, and a new arc furnace cover steel structure market, which makes, needs 23000
Member or so, repairing a steel structure needs 3000 yuan or so, i.e. every this 20000 yuan or so of steel structure drop；
(3) the method for the present invention realizes that remaining steel structure recycles, and reduces the discharge and pollution of industrial refuse, improve enterprise and
Social benefit improves electric arc furnaces factory working efficiency and benefit.
Description of the drawings
Technical scheme of the present invention is described in further detail below with reference to drawings and examples, but should
Know, these attached drawings are only designed for task of explanation, therefore not as the restriction of the scope of the invention.In addition, except non-specifically
It points out, these attached drawings are meant only to conceptually illustrate structure construction described herein, without to be drawn to scale.
Fig. 1 is the structure diagram of the arc furnace cover after being repaired using restorative procedure of the present invention；
Fig. 2 is the vertical view of Fig. 1.
Specific embodiment
Firstly, it is necessary to explanation, etch of the present invention is illustrated by way of example and burns mistake arc furnace cover below
Restorative procedure features and advantages etc., however all descriptions are intended merely to what is illustrated, and should not be construed as to this hair
Bright formation any restrictions.In addition, the arbitrary single technical characteristic that is described by or implies in embodiment each mentioned by this paper or
Person is shown or implicit arbitrary single technical characteristic in the drawings, still can these technical characteristics (or its equivalent) it
Between continue it is arbitrary combination or delete, so as to obtain may herein directly refer to the present invention other more realities
Apply example.
Incorporated by reference to reference to figure 1 and Fig. 2, below electric arc furnaces is just lost to be burnt to etch of the present invention by the embodiment that this is provided
The restorative procedure of lid illustrates.
Embodiment 1
The restorative procedure for losing arc furnace cover is burnt in a kind of etch, including step in detail below：
Step S1, arc furnace cover handling
It will use the arc furnace covers of guideline lives from electric arc furnaces by under crane or traveling crane, being hoisted to designated treatment and showing
；
Step S2, remaining steel structure separation
Using special equipment and tool, to being detached with the remaining castable refractory in rear arc furnace cover with remaining steel structure,
In separation process, the deformation that strength generates the round bearing plate 2 and lifting lug 1 of remaining steel structure and remaining skirtboard 3 should use up
Amount is maintained in prescribed limit；
Step S3, drawing is repaired in design
1) height of remaining skirtboard, is measured；
2), according to the height of remaining skirtboard, the diameter of round bearing plate and load-bearing requirements setting enhancing bar 4 and dowel 5,
6, the lower end for enhancing bar is no more than plane where former skirtboard lower end；
Step S4, Repair gene
1), between the round bearing plate 2 to remaining steel structure and lifting lug 1, round bearing plate 2 and remaining 3 junction of skirtboard, by force
Degree is inadequate, injury region, and repair welding is carried out by welding conditions requirement；
2) cleaning polishing, is carried out to the lower part of remaining skirtboard and round bearing plate, grinds off remaining skirtboard and round bearing plate
Remaining castable on lower part, then the bar of welding enhancing by drawing, enhances bar firm welding；
3), after all enhancing bars 4 have welded, then by drawing around enhancing bar welding twice dowel 5,6；
4) verification inspection processing, is carried out as required to the remaining steel structure after reparation, it is qualified to examine, after meeting the requirements, storage
It is for use at drying；
Step S5, moulding by casting
1), the sundries in mold is cleaned up, the installation of 8 mold of counter electrode hole is stable and firm, it uniformly applies and brushes boundary
Face agent pastes interface paper, and being sealed prevents material leakage；
2), the brush coating of wax on electrode punch die, one layer of machine oil of brush and must not long-pending oil on bottom plate；
3), the remaining steel structure after qualified repair is hung in arc furnace cover mold, according to the drawing size requirements, location of proofreading
Steel structure position, determine it is errorless after, by steel structure firm position, qualified integrally firm etch will be examined to burn and lose the reparation of arc furnace cover
Shake table on method mold hoisting, the restorative procedure die bottom plate that mistake arc furnace cover is burnt in etch are securely connect with vibration table surface；
4) when, pouring into a mould, continuous three days or more the lowest temperature >=3 DEG C are needed, if winter is kneaded cast, need to first prepare 30-
40 DEG C of warm water；
5), by the raw material prepared in kolleroang first dry-mixed 0.5min, then add in steel fibre mixed grind 0.5-1min, then
Be slowly added to suitable quantity of water, bonding agent mixed grind 2-4min to pug is uniformly mixed, mobility is suitable, discharging；
6) mixed castable 7 equably, is poured into etch to burn in the restorative procedure for losing arc furnace cover, opens shake table and shakes
It is dynamic, to being glowed without apparent bubble, until cast height is concordant at the top of round bearing plate, poured into a mould with castable refractory vibrate into
Type.
Embodiment 2
In addition, in the restorative procedure for losing arc furnace cover is burnt in the etch of the present invention, it can be with it is further contemplated that upper
It is further included before stating step S4：Step S6, shape corrects
The shape deformation of round bearing plate and lifting lug to remaining steel structure and remaining skirtboard go beyond the scope or deform it is serious,
Equipment and tool should be used to be corrected processing, round load-bearing plate flatness reaches ± 15mm；Deviation reaches on the outside of remaining skirtboard
±20mm。
Embodiment 3
In addition, in the restorative procedure for losing arc furnace cover is burnt in the etch of the present invention, it can be with it is further contemplated that above-mentioned
Enhancing bar 4, dowel 5,6 are made by screw-thread steel.
Embodiment 4
In addition, in the restorative procedure for losing arc furnace cover is burnt in the etch of the present invention, it can be with it is further contemplated that above-mentioned
Twice dowel 5,6 is arranged in parallel, and is welded respectively with enhancing bar 4, enhances the intensity of steel structure.
Embodiment 5
In addition, in the restorative procedure for losing arc furnace cover is burnt in the etch of the present invention, it can be with it is further contemplated that above-mentioned
Enhancing bar 4 takes the shape of the letter U or V-arrangement or arc-shaped, best to select U-shaped enhancing bar.
It etch of the present invention is only elaborated by way of example above burns and lose the restorative procedure of arc furnace cover this few example only
For illustrating the principle of the present invention and embodiments thereof is used rather than limitation of the present invention, in the spirit for not departing from the present invention and
In the case of range, those skilled in the art can also make various modifications and improvement.Therefore, all equivalent technical solutions are equal
Scope of the invention should be belonged to and every claim by the present invention is limited.
Claims (5)
1. the restorative procedure for losing arc furnace cover is burnt in a kind of etch, which is characterized in that including step in detail below：
Step S1, arc furnace cover handling
By the arc furnace cover for using guideline lives by under crane or traveling crane, being hoisted to designated treatment scene from electric arc furnaces；
Step S2, remaining steel structure separation
Using special equipment and tool, to being detached with the remaining castable refractory in rear arc furnace cover with remaining steel structure, detaching
In the process, the deformation that strength generates the round bearing plate (2) and lifting lug (1) of remaining steel structure and remaining skirtboard (3) should
It is maintained in prescribed limit as possible；
Step S3, drawing is repaired in design
1) height of remaining skirtboard, is measured；
2), according to the height of remaining skirtboard (3), the diameter of round bearing plate (2) and load-bearing requirements setting enhancing bar (4) and connection
Muscle (5,6), the lower end for enhancing bar are no more than plane where former skirtboard lower end；
Step S4, Repair gene
1), to the round bearing plate (2) of remaining steel structure and lifting lug (1), round bearing plate (2) and remaining skirtboard (3) junction it
Between, insufficient strength, injury region carry out repair welding by welding conditions requirement；
2) cleaning polishing, is carried out to the lower part of remaining skirtboard (3) and round bearing plate (2), grinds off remaining skirtboard and round load-bearing
Remaining castable on plate lower part, then the bar of welding enhancing by drawing, enhances bar firm welding；
3), after all enhancing bars have welded, then by drawing around enhancing bar welding twice dowel；
4) verification inspection processing, is carried out as required to the remaining steel structure after reparation, it is qualified to examine, and after meeting the requirements, is stored in dry
Dry place is for use；
Step S5, moulding by casting
Remaining steel structure after qualified repair is put into arc furnace cover mold, is corrected to specified position, positioning is fixed, poured with fire resisting
Vibration moulding is poured into a mould in material feeding.
2. the restorative procedure for losing arc furnace cover is burnt in etch according to claim 1, which is characterized in that above-mentioned steps S4 it
Before further include：Step S6, shape corrects
The shape deformation of round bearing plate (2) and lifting lug (1) and remaining skirtboard (3) to remaining steel structure goes beyond the scope or deforms sternly
Weight, equipment and tool should be used to be corrected processing, round load-bearing plate flatness reaches ± 15mm；Deviation on the outside of remaining skirtboard
Reach ± 20mm.
3. the restorative procedure for losing arc furnace cover is burnt in etch according to claim 1 or 2, which is characterized in that the enhancing bar
(4), dowel (5,6) is made by screw-thread steel.
4. the restorative procedure for losing arc furnace cover is burnt in etch according to claim 1 or 2, which is characterized in that the twice connect
It connects muscle (5,6) to be arranged in parallel, be welded respectively with enhancing bar (4).
5. the restorative procedure for losing arc furnace cover is burnt in etch according to claim 1 or 2, which is characterized in that the enhancing bar
(4) it takes the shape of the letter U or V-arrangement or arc-shaped.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610227407.7A CN105890342B (en) | 2016-04-12 | 2016-04-12 | The restorative procedure for losing arc furnace cover is burnt in a kind of etch |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610227407.7A CN105890342B (en) | 2016-04-12 | 2016-04-12 | The restorative procedure for losing arc furnace cover is burnt in a kind of etch |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105890342A CN105890342A (en) | 2016-08-24 |
| CN105890342B true CN105890342B (en) | 2018-06-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610227407.7A Active CN105890342B (en) | 2016-04-12 | 2016-04-12 | The restorative procedure for losing arc furnace cover is burnt in a kind of etch |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4152534A (en) * | 1976-12-08 | 1979-05-01 | Kyoei Seiko Kabushiki Kaisha | Furnace roof for the electric arc furnace |
| JPH03186187A (en) * | 1989-12-15 | 1991-08-14 | Nkk Corp | Repairing method for spout of electric furnace |
| CN2600774Y (en) * | 2002-10-21 | 2004-01-21 | 吴钦合 | Brick type electric arc furnace lid |
| CN201740395U (en) * | 2010-06-04 | 2011-02-09 | 河北钢铁股份有限公司唐山分公司 | Improved coke dry quenching furnace lid |
-
2016
- 2016-04-12 CN CN201610227407.7A patent/CN105890342B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4152534A (en) * | 1976-12-08 | 1979-05-01 | Kyoei Seiko Kabushiki Kaisha | Furnace roof for the electric arc furnace |
| JPH03186187A (en) * | 1989-12-15 | 1991-08-14 | Nkk Corp | Repairing method for spout of electric furnace |
| CN2600774Y (en) * | 2002-10-21 | 2004-01-21 | 吴钦合 | Brick type electric arc furnace lid |
| CN201740395U (en) * | 2010-06-04 | 2011-02-09 | 河北钢铁股份有限公司唐山分公司 | Improved coke dry quenching furnace lid |
Non-Patent Citations (1)
| Title |
|---|
| 中小型矿热电炉炉盖选型及修复实践;沈林明，钟开虎;《中国锰业》;20150930;第33卷(第3期);第42-44页 * |
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| Publication number | Publication date |
|---|---|
| CN105890342A (en) | 2016-08-24 |
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| TA01 | Transfer of patent application right |
Effective date of registration: 20180428 Address after: 243071 53 intelligent equipment Industrial Park in Yushan Economic Development Zone, Ma'anshan, Anhui Applicant after: Ruitai Magang new Mstar Technology Ltd Applicant after: Magang (Group) Holding Company Ltd. Address before: 243000 No. 2256, middle section of Tianmen Road, Ma'anshan, Anhui Applicant before: ANHUI MA STEEL REFRACTORY CO., LTD. |
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