CN101837448A - Repairing method for steel ladle and iron ladle - Google Patents
Repairing method for steel ladle and iron ladle Download PDFInfo
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- CN101837448A CN101837448A CN200910047968A CN200910047968A CN101837448A CN 101837448 A CN101837448 A CN 101837448A CN 200910047968 A CN200910047968 A CN 200910047968A CN 200910047968 A CN200910047968 A CN 200910047968A CN 101837448 A CN101837448 A CN 101837448A
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Abstract
The invention relates to a repairing method for steel ladle and iron ladle, which is used for disassembling and changing a trunnion fixedly on a body of the steel ladle and iron ladle in a welding way. The method comprises the following steps of: preparing for a new trunnion; setting up a trunnion dismounting construction frame; cleaning an internal insulation layer of the body; implementing a positioning mark for mounting the new trunnion on the body; cutting a welding seam for connecting the trunnion with the inner wall of the body; gradually carrying out pressurization on the trunnion by using a hydraulic device to enable the trunnion to be slowly extruded out; carrying out detection and measurement on a shaft hole after the trunnion is extruded out and totally separated from the shaft hole of the body; slowly pressing the new trunnion in the shaft hole to a position needing to be welded by the hydraulic device, and then detecting the assembly positioning size; welding the new trunnion by a welding way; and carrying out nondestructive testing after welding and then carrying out heat treatment and reinspection. The invention has short repair time and high efficiency, can avoid abnormal scrap of the body, saves use cost, prolongs the service life of the body and is beneficial to stabilizing the production.
Description
Technical field
The present invention relates to a kind of restorative procedure of large-scale metallurgical equipment, especially design the restorative procedure of the ladle iron bag of a kind of splendid attire molten steel, molten iron or slag scum etc.
Background technology
As everyone knows, employed steel ladle in the modern steel production technology (abbreviation ladle), ladle (being called for short the iron bag) and iron and steel slag ladle metallurgical equipments such as (abbreviation slag ladles) constantly develop towards direction efficient, that maximize, not only equipment size and tonnage are big, and the structural complexity increase, technical difficulty also increases thereupon.As: ladle and iron bag have reached 300 tons of capacity.
Yet, owing to limit by various objective condition, add the importance (the ladle iron of 300 tons of capacity wraps in aerial operation) of secure context, in the past, never to the history of this ladle and large-scale special installation place under repair of iron bag or reparation,, ladle or iron bag just do to scrap processing both at home and abroad in case existing defective to exceed standard.
At present, also stagnate and be confined to the repairing of ladle or iron bag body, promptly, as shown in Figure 1, the structure of ladle or iron bag (below be referred to as " ladle ") mainly is to be made of ladle body 2 and 1,1 of two gudgeon being fixed on two sides of ladle body top, if the ladle body produces defectives such as local deformation, uneven, local bulge, crackle, just does the repairing reparation of corresponding site, ladle after the body reparation just can come into operation again, to save use cost etc.But, do not exist at ladle body 2 under the situation of defective, if be installed in the defective that the gudgeon 1 on the ladle body 2 produces as body 2, also this main equipment of whole ladle can only be done to scrap processing at present.Main cause is: because the security of this main equipment of ladle is important especially, if there is not safe and reliable method that gudgeon is changed, will produce catastrophic effect, the repairing of gudgeon is different from the ladle body and repairs, need understand fully that not only gudgeon is with respect to ladle main body structure mechanism and mounting technology, and gudgeon to change technical difficulty big, have a big risk, therefore do not have a kind of scientific and reasonable restorative procedure of gudgeon being removed, installed new gudgeon so far.So, present ladle restorative procedure, only,, do not have a kind of restorative procedure of its dismounting being installed new gudgeon, thereby there are the following problems if the ladle gudgeon produces the defective that can not repair at the restorative procedure of ladle body:
1) cause new equipment to be scrapped unusually.Sometimes the ladle body is good, and just the ladle gudgeon produces the excessive defect that can not repair, just whole ladle can only be scrapped, and causes this main equipment input cost of ladle to increase and unnecessary waste;
2) cause field apparatus turnover difficulty.Because the manufacturing cycle of large-scale metallurgical equipment such as ladle is long, from the planning to the contract, tasks such as buying, processing and manufacturing, check, transportation all finish, and generally need half a year to year.In addition, the use of large-scale ladle is to calculate the number of turnover by ordinary production molten steel amount, and determining does not then have plentiful spare unit amount by usage quantity.In case occur scrapping unusually, then the volume of the circular flow of ladle is not enough, new product is difficult in time replenish, and then can influence production.
3) be unfavorable for cost efficiency.The repair method that is only limited to the ladle body of this routine causes the wasting of resources, does not excavate the potentiality of equipment available resources to greatest extent, both has been unfavorable for technological progress, is unfavorable for cost efficiency, is unfavorable for that also equipment lengthens the life.
Summary of the invention
Problem in view of above-mentioned existence, the object of the present invention is to provide a kind of restorative procedure of ladle iron bag, this method repair time is short, efficient is high, safe and reliable, by replacing to ladle iron bag gudgeon, thereby can keep re-using of entire equipment body, avoided scrapping the unnecessary waste that is caused unusually, helped steady production.
For achieving the above object, the technical scheme of the restorative procedure of ladle iron bag of the present invention is, the gudgeon that is weldingly fixed on the ladle iron bag body is changed, and its feature comprises the steps:
Prepare to need the gudgeon on the described body is changed the new gudgeon of usefulness;
Described gudgeon place at described body sets up gudgeon dismounting scaffold;
Base insulating layer to described body is cleared up;
Before the described gudgeon of dismounting, on described body, implement described new gudgeon the telltale mark of usefulness is installed;
Cut described gudgeon and described inner body wall attachment weld;
To the direction of outside described gudgeon is progressively pressurizeed from the inside of described body with hydraulic means, described gudgeon is slowly extruded;
Described gudgeon is forced out, break away from the axis hole on the described body fully after, described axis hole is checked, is measured;
Described new gudgeon slowly is pressed into the described axis hole to required welding position from the outside of described body to the direction of inside with hydraulic means, checks the assembling and positioning size then;
By welding manner the described new gudgeon that is pressed in the described axis hole is welded;
Carry out Non-Destructive Testing after the welding, heat-treat then and review.
In above-mentioned technical scheme, the material of described new gudgeon is selected the 35# quality carbon steel for use, forges after qualified through detecting a flaw, and forging reaches hardness HB=131～187 through normalizing, tempering heat treatment.
In above-mentioned technical scheme, when described gudgeon of cutting and described inner body wall attachment weld, adopt carbon arc air gouging and the mechanical grinding mode of combining to remove attachment weld, and guarantee that described gudgeon does not have weld seam with described body and is connected.
In above-mentioned technical scheme, after described axis hole is checked, measured, described axis hole is carried out accurate reconditioning.
In above-mentioned technical scheme, after described axis hole being checked, measured or carry out accurate reconditioning, new gudgeon is installed.
Weld preheating and layer temperature control adopt computer temperature controller device automatic control electrical heating method heating bevel for welding and groove both sides 150mm scope interior to 100 ℃～150 ℃, and interlayer temperature is not less than preheat temperature.
In technique scheme, after described assembling and positioning size is checked, the described axis hole place of described body is offered groove weld.
In technique scheme, described welding is the mode that adopts manual electric arc welding.
In technique scheme, described welding is the mode that adopts the manual automanual dc source reversed polarity of carbon dioxide.
In technique scheme, described hydraulic means is 8～10 tons of hydraulic jack, and described heat treatment is: heating-up temperature is 600 ± 20 ℃; Programming rate is≤150 ℃/h; Temperature retention time is 240min; Cooling rate is≤100～150 ℃/h, is air cooling below 400 ℃.
Adopt the present invention, owing to be that a kind of what is called that the gudgeon that can not repair that is weldingly fixed on the ladle iron bag body is changed " is changed axle and rescue bag " method, therefore, under the flawless situation of ladle iron bag body, as long as the gudgeon that defective can not be repaired is changed, just can avoid scrapping unusually of ladle iron bag, save use cost, have the advantage of cost efficiency.
In addition, the method of this " change axle and rescue bag ", the time of actual demolition, installation gudgeon construction can finish in week, than scrapping ladle iron bag, purchasing new ladle iron bag in addition, the cycle is short, instant effect, the use turnover quantity that can guarantee ladle iron bag is stable, because the manufacturing cycle of new ladle iron bag is longer, transport etc. from planning purchase, generally need the time more than half a year to one year.
Description of drawings
Fig. 1 is the surface structure schematic diagram of expression ladle (or iron bag, be referred to as ladle below).
Fig. 2 is the forging heat treatment cycle curve figure that expression is installed in the gudgeon of using on the ladle.
Fig. 3 is the post weld heat treatment process curve figure after the expression gudgeon is welded on the ladle.
Fig. 4 is the flow diagram of the restorative procedure of expression ladle of the present invention.
The specific embodiment
Below, specific embodiment of the restorative procedure of ladle of the present invention, Tie Bao (below, ladle iron bag is referred to as ladle explanation) is described with reference to the accompanying drawings.
As shown in Figure 1, the structure of ladle mainly comprises body 2 and the relative gudgeon 1,1 of difference welded and installed in body 2 tops two sides.
Do not exist at ladle body 2 under the situation of defective, if the gudgeon 1 that is installed on the ladle body 2 produces the defective that can not repair, then this gudgeon 1 is removed, new gudgeon is installed, to avoid unnecessary the scrapping of ladle body, reduce the production use cost, because the price of gudgeon 1 only accounts for about 10% of ladle body 2.Therefore, the restorative procedure of ladle proposed by the invention has following steps.
1) preparation needs change the gudgeon on the body 21 the new gudgeon (not shown) of usefulness.Select the 35# quality carbon steel for use.New gudgeon process technology requires: select the 35# steel forgings for use, satisfy GB/T 699-1988 " Fine Steel Casting iron technical conditions ".(blank, semi-finished product) adopt the UT flaw detection, and the gudgeon flaw detection meets standard GB/T6402-91 requirement, and it is qualified being not less than the II level.Forge and press the examination of JB/T5000.8-1998 " forging general technical specifications " V group standard.Forging need pass through normalizing+tempering heat treatment, finally reaches hardness HB=131～187.Normalizing+the tempering heat treatment curve as shown in Figure 2.
2) set up gudgeon dismounting scaffold (not shown) at gudgeon 1 place of body 2.The scaffold of dismounting gudgeon 1 can adopt scaffold or lifting platform etc., is convenient to construction and has security get final product.
3) base insulating layer (not shown) of body 2 is cleared up.This cleaning is the necessary preparation in the early stage of construction and welding.
4) before dismounting gudgeon 1, on body 2, implement the telltale mark (not shown) that new gudgeon is installed usefulness.This telltale mark is used for the phenomenon that do not misplace when new gudgeon is installed.Because gudgeon is round, the inwall of body 2 also is an arc surface, and both arc radius differ greatly, and therefore, only performs mark and just can guarantee to be in place.
5) cutting gudgeon 1 and body 2 inwall attachment welds.This is the steps necessary that with hydraulic means gudgeon is ejected in order to prepare, because gudgeon and body 2 inwalls are welded to connect, does not connect welding if do not cut, and can not push up gudgeon 1 with hydraulic means, must for a full due attachment weld be cut away.
Above-mentioned cutting can adopt carbon arc air gouging and the mechanical grinding mode of combining to remove attachment weld, and guarantees that gudgeon 1 is connected with body 2 no weld seams.
6) to the direction of outside gudgeon 1 is progressively pressurizeed from the inside of body 2 with hydraulic means (not shown), gudgeon 1 is slowly extruded.In order successfully easily gudgeon 1 to be extruded, employed hydraulic means is 8～10 tons of hydraulic jack.And, just beginning inside from body 2 when the direction of outside is pressurizeed to gudgeon 1, attempt the slowly pressurization of property ground earlier, for example with the power starting pressurization of 100-200kg, progressively pressurization then.In addition, the gudgeon extrusion should evenly and slowly, the per minute amount of shifting out be observed quantity with the millimeter, until gudgeon 1 is extruded.
7) after gudgeon 1 is forced out, breaks away from fully axis hole (not shown) on the body 2, axis hole is checked, measured.According to the check measurement situation, axis hole is carried out accurate reconditioning.
8) new gudgeon slowly is pressed into the axis hole to required welding position from the outside of body 2 to the direction of inside with hydraulic means, checks the assembling and positioning size then.
9) by welding manner the new gudgeon that is pressed in the axis hole is welded.
10) carry out Non-Destructive Testing after the welding, heat-treat then and review.
In the present embodiment, after axis hole is checked, measured, or after according to circumstances axis hole being carried out accurate reconditioning, the electrical heating preheating is carried out in the zone in gudgeon hole, with the new gudgeon of convenient installation.
In the present embodiment, after the assembling and positioning size is checked, preferably the axis hole place of body 2 is offered groove and weld.
In addition, above-mentioned welding is the mode that adopts manual electric arc welding, also adopts the mode of the manual automanual dc source reversed polarity of carbon dioxide.
When adopting the mode of manual electric arc welding, welding rod is selected J507 or E5015 for use, or E5015-G or J507RH, Φ 3.2mm bottoming, Φ 4.0mm welding.Weld preheating and layer temperature control: adopt computer temperature controller device automatic control electrical heating method heating bevel for welding and groove both sides 150mm scope interior to 100 ℃～150 ℃, interlayer temperature is not less than preheat temperature.Welding requirements: when adopting manual welding rod to weld, use dc source, adopt E5015-G (J507RH) φ 4mm welding rod, welding current is 150A, every root bead bar weld length is controlled at 150～200mm, multi-pass welding, way scarfing cinder, welded together and it has been carried out the stress-removal processing, and cleaned down with wire brush and to prevent weld defect with the vibration rifle.
If when adopting the manual semi-automatic method of carbon dioxide to weld, with the welding of dc source reversed polarity; Welding wire uses and takes the plug and play principle, opens bag the same day and uses up the same day; The carbon dioxide that is used to weld should meet GB6052 " industrial liquid carbon dioxide " first quality standard, and volume capacity should be greater than 99.5%, and water content should be not more than 0.05%.Stop using for the time when the carbon dioxide gas pressure in the bottle, prevent to produce the welding pore less than 1MPa.
After being welded on new gudgeon on the ladle body by the way, carry out Non-Destructive Testing.JB/T4730-2005 and GB/T2970-91 " medium plate supersonic testing method " or GB/T 6402-91 are selected in Non-Destructive Testing for use.
After the Non-Destructive Testing, heat-treating, is to heat-treat to new gudgeon and around being welded on axis hole on the ladle body.As shown in Figure 3, heat treatment is: heating-up temperature is 600 ± 20 ℃; Programming rate is≤150 ℃/h; Temperature retention time is 240min; Cooling rate is≤100～150 ℃/h, is air cooling below 400 ℃.
In the present embodiment, the reinspection of being carried out after the heat treatment, its test stone is by carrying out as following table 1.
Table 1
| Title | The items/materials trade mark | Standard No. |
| Gudgeon | The 35# forged steel pieces | ??GB699-1998 |
| The body seam inspection | ??UT | ??JB/T4730.3-2005 |
| The face of weld flaw detection | ??PT | ??JB/T4730.5-2005 |
By adopting the restorative procedure of above-mentioned ladle of the present invention, can obtain following effect:
1) lacks efficient height, instant effect repair time.
2) avoid the body of ladle and iron bag to scrap unusually, help steady production.
3) help cost efficiency, also help the prolongation service life of equipment.
Claims (10)
1. the restorative procedure of a ladle iron bag is the method that the gudgeon on the body that is weldingly fixed on ladle iron bag is changed, and it is characterized in that, described method comprises the steps:
Prepare to need the gudgeon on the described body is changed the new gudgeon of usefulness; Described gudgeon place at described body sets up gudgeon dismounting scaffold; Base insulating layer to described body is cleared up; Before the described gudgeon of dismounting, on described body, implement described new gudgeon the telltale mark of usefulness is installed; Cut described gudgeon and described inner body wall attachment weld; To the direction of outside described gudgeon is progressively pressurizeed from the inside of described body with hydraulic means, described gudgeon is slowly extruded; Described gudgeon is forced out, break away from the axis hole on the described body fully after, described axis hole is checked, is measured; Described new gudgeon slowly is pressed into the described axis hole to required welding position from the outside of described body to the direction of inside with hydraulic means, checks the assembling and positioning size then; By welding manner the described new gudgeon that is pressed in the described axis hole is welded; Carry out Non-Destructive Testing after the welding, heat-treat then and review.
2. the restorative procedure of ladle iron bag as claimed in claim 1 is characterized in that the material of described new gudgeon is selected the 35# quality carbon steel for use, forges after qualified through detecting a flaw, and forging reaches hardness HB=131～187 through normalizing, tempering heat treatment.
3. the restorative procedure of ladle iron bag as claimed in claim 1, it is characterized in that, when described gudgeon of cutting and described inner body wall attachment weld, adopt carbon arc air gouging and the mechanical grinding mode of combining to remove attachment weld, and guarantee that described gudgeon does not have weld seam with described body and is connected.
4. the restorative procedure of ladle iron bag as claimed in claim 1 is characterized in that, after described axis hole is checked, measured, described axis hole is carried out accurate reconditioning.
5. the restorative procedure of ladle iron bag as claimed in claim 1 is characterized in that, after described axis hole being checked, measured or carry out accurate reconditioning, new gudgeon is installed.
6. the restorative procedure of ladle iron bag as claimed in claim 1, it is characterized in that, weld preheating and layer temperature control adopt computer temperature controller device automatic control electrical heating method heating bevel for welding and groove both sides 150mm scope interior to 100 ℃～150 ℃, and interlayer temperature is not less than preheat temperature.
7. the restorative procedure of ladle iron bag as claimed in claim 1 is characterized in that, after described assembling and positioning size is checked, the described axis hole place of described body is offered groove weld.
8. as the restorative procedure of claim 1 or 7 described ladle iron bags, it is characterized in that described welding is the mode that adopts manual electric arc welding.
9. as the restorative procedure of claim 1 or 7 described ladle iron bags, it is characterized in that described welding is the mode that adopts the manual automanual dc source reversed polarity of carbon dioxide.
10. the restorative procedure of ladle iron bag as claimed in claim 1 is characterized in that, described hydraulic means is 8～10 tons of hydraulic jack, and described heat treatment is: heating-up temperature is 600 ± 20 ℃; Programming rate is≤150 ℃/h; Temperature retention time is 240min; Cooling rate is≤100～150 ℃/h, is air cooling below 400 ℃.
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| Application Number | Priority Date | Filing Date | Title |
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| CN200910047968A CN101837448A (en) | 2009-03-20 | 2009-03-20 | Repairing method for steel ladle and iron ladle |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910047968A CN101837448A (en) | 2009-03-20 | 2009-03-20 | Repairing method for steel ladle and iron ladle |
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| CN101837448A true CN101837448A (en) | 2010-09-22 |
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| CN200910047968A Pending CN101837448A (en) | 2009-03-20 | 2009-03-20 | Repairing method for steel ladle and iron ladle |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101992375A (en) * | 2010-11-12 | 2011-03-30 | 莱芜钢铁集团有限公司 | Process method for replacing trunnion of ladle |
| CN103212702A (en) * | 2013-05-08 | 2013-07-24 | 重庆钢铁(集团)有限责任公司 | Steel ladle trunnion and method for repairing steel ladle by using same |
| CN104907759A (en) * | 2014-03-10 | 2015-09-16 | 宝山钢铁股份有限公司 | Large steel ladle repair method |
| CN111889661A (en) * | 2020-07-29 | 2020-11-06 | 新兴铸管股份有限公司 | Repair method of intermediate tank |
| CN111940993A (en) * | 2020-10-19 | 2020-11-17 | 中国航发沈阳黎明航空发动机有限责任公司 | Method for repairing cracks on mounting edge of bearing frame of inclined support plate |
-
2009
- 2009-03-20 CN CN200910047968A patent/CN101837448A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101992375A (en) * | 2010-11-12 | 2011-03-30 | 莱芜钢铁集团有限公司 | Process method for replacing trunnion of ladle |
| CN101992375B (en) * | 2010-11-12 | 2012-10-03 | 莱芜钢铁集团有限公司 | Process method for replacing trunnion of ladle |
| CN103212702A (en) * | 2013-05-08 | 2013-07-24 | 重庆钢铁(集团)有限责任公司 | Steel ladle trunnion and method for repairing steel ladle by using same |
| CN103212702B (en) * | 2013-05-08 | 2015-11-04 | 重庆钢铁(集团)有限责任公司 | Ladle trunnion and utilize this ladle trunnion to carry out the method for ladle reparation |
| CN104907759A (en) * | 2014-03-10 | 2015-09-16 | 宝山钢铁股份有限公司 | Large steel ladle repair method |
| CN111889661A (en) * | 2020-07-29 | 2020-11-06 | 新兴铸管股份有限公司 | Repair method of intermediate tank |
| CN111889661B (en) * | 2020-07-29 | 2021-11-05 | 新兴铸管股份有限公司 | Repair method of intermediate tank |
| CN111940993A (en) * | 2020-10-19 | 2020-11-17 | 中国航发沈阳黎明航空发动机有限责任公司 | Method for repairing cracks on mounting edge of bearing frame of inclined support plate |
| CN111940993B (en) * | 2020-10-19 | 2021-01-12 | 中国航发沈阳黎明航空发动机有限责任公司 | Method for repairing cracks on mounting edge of bearing frame of inclined support plate |
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Open date: 20100922 |