CN1704481A - Drill bit for taphole of blast furnace and method for producing same - Google Patents
Drill bit for taphole of blast furnace and method for producing same Download PDFInfo
- Publication number
- CN1704481A CN1704481A CN 200410024854 CN200410024854A CN1704481A CN 1704481 A CN1704481 A CN 1704481A CN 200410024854 CN200410024854 CN 200410024854 CN 200410024854 A CN200410024854 A CN 200410024854A CN 1704481 A CN1704481 A CN 1704481A
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- drill bit
- blast furnace
- throat
- pedestal
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- 238000004519 manufacturing process Methods 0.000 title claims description 15
- 238000000034 method Methods 0.000 claims abstract description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 95
- 229910052742 iron Inorganic materials 0.000 claims description 49
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims description 30
- 238000003466 welding Methods 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 6
- 229910052799 carbon Inorganic materials 0.000 claims description 6
- 238000005266 casting Methods 0.000 claims description 4
- 230000015572 biosynthetic process Effects 0.000 claims description 2
- 229910000975 Carbon steel Inorganic materials 0.000 claims 1
- 241001074085 Scophthalmus aquosus Species 0.000 claims 1
- 239000010962 carbon steel Substances 0.000 claims 1
- 238000005553 drilling Methods 0.000 abstract description 20
- 238000013022 venting Methods 0.000 abstract 3
- 241000125205 Anethum Species 0.000 abstract 1
- 238000009827 uniform distribution Methods 0.000 abstract 1
- 238000001816 cooling Methods 0.000 description 13
- 239000000463 material Substances 0.000 description 9
- 239000011148 porous material Substances 0.000 description 8
- 238000005520 cutting process Methods 0.000 description 7
- 238000010079 rubber tapping Methods 0.000 description 5
- 238000010926 purge Methods 0.000 description 4
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 244000197975 Solidago virgaurea Species 0.000 description 2
- 235000000914 Solidago virgaurea Nutrition 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 238000007669 thermal treatment Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910001315 Tool steel Inorganic materials 0.000 description 1
- 102000001999 Transcription Factor Pit-1 Human genes 0.000 description 1
- 108010040742 Transcription Factor Pit-1 Proteins 0.000 description 1
- 229910000754 Wrought iron Inorganic materials 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000003818 cinder Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 235000013312 flour Nutrition 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 150000002505 iron Chemical class 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 210000000664 rectum Anatomy 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
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- Blast Furnaces (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
Disclosed is a drill bit for taphole of blast furnace, which comprises a base and three blades, the base is provided with a venting hole in the center, and side air passages in communication with the central venting hole, the blades are in uniform distribution on the base, the head of the blades are of trapezoidal structure inclining toward the central venting hole, the exterior height of the drilling bit is 13-16 mm. The invention also discloses the process for making the dill bit.
Description
Technical field
The invention belongs to the ironmaking technology field, be specifically related to drill bit and manufacture method thereof that a kind of blast furnace iron notch taphole drilling machine drilling rod is used.
Technical background
The operation of blast furnace front slagging iron is the crucial link that blast furnace is produced, and in time opening goes out the stable smooth operation that most slag iron can not only keep blast furnace to produce, and can improve the ability that blast furnace is resisted extraneous unfavorable factor influence to greatest extent.Blast furnace production process requires in the cupola well slag iron liquid level lower and keep relative stability, otherwise can occur that blanking is irregular, blast wandering, furnace temperature fluctuation even the unusual working of a furnace such as slump material, harm blast furnace ordinary production occur.Therefore job requirements reaches " clean cupola well " operation before the State of Blast Furnace.
Guaranteeing to beat tapping outlet in the predetermined short period and obtaining the ideal iron mouth pore passage is fundamental requirement to the operation of tap cinder iron, is the key point that realizes that clean cupola well is operated.The ideal iron mouth pore passage requires the about diameter of iron mouth to be consistent, and the duct wall is straight smooth, reach this purpose, needs to be equipped with advanced taphole drilling machine and high performance drilling rod and the drill bit that matches.Under the certain condition of the iron mouth degree of depth, stemming performance, stemming sintering time, taphole drilling machine motor power, the used time of opening is depended on the cutting power and the chip removal quality of drill bit, iron mouth pore passage whether the aperture profile that evenly, smoothly depends on drill bit whether remain unchanged in initial stage of opening and latter stage be the high temperature wear resistant performance of drill bit.
Existing domestic and international blast furnace is generally used " an opening method ", but have the following disadvantages mostly or shortcoming: (1) drill bit structure shape or off size reason, as shown in Figure 1 and Figure 2, the corner angle of the angle of throat 30 on band ventilating pit 20 pedestals 10 are not sharp, the face of tool is little, cause the bit cutting ability, iron mouth opening time is longer, generally wants about 7～10 minutes.Sometimes need to use 2 drilling rods could beat tapping outlet; (2) the drill bit cooling performance is relatively poor, and what have uses single air cooling, the drill bit air flue opening angle that has or the reason of What people saying does not agree with one another, and angle of throat can not fully obtain cooling, and hot strength can not guarantee; (3) selection of drill bit material is not good, and the steel drill bit hardness that has is low, wears no resistance.Or thermohardening is low, more to the Tie Kou depths easily anneal, softening transform, make iron mouth pore passage inhomogeneous.
Because the defective of above-mentioned drill bit, iron mouth are mainly got through by rapping when getting into certain depth usually, this stablizes very unfavorablely to safeguarding iron mouth mud drum and sidewall bricking, also easily causes Lou bad phenomenon such as iron mouth, influences operation quality.
In addition, existing drill bit complete processing complexity is with material cost height.Unit that home and overseas has is with Wrought Tool Steel mechanical workout drill bit, and its hardness and thermohardening height, wear resistance are good, but material cost is very high, and course of processing complexity also needs thermal treatment.For reducing use cost, require the same drill bit of blast furnace to use secondary, promptly require drilling rod when taphole drilling is opened, just returning immediately, with a gold medal rod iron mouth is disclosed out again.This just causes: can not guarantee that drill bit is not by the molten iron melting loss; Can not guarantee that drill bit can once beat tapping outlet when using for the second time; It is unfavorable to mud drum protection and cupola well sidewall longevity to disclose the iron mouth with golden rod, and has increased the consumption of golden rod.
Summary of the invention
The purpose of this invention is to provide tapping outlet of a kind of blast furnace drill bit and manufacture method thereof, it creeps into efficiently, makes simple, with low cost.
Drill bit of the present invention is designed and developed based on following technical thought:
(1) shape of drill bit, structure and edge length have material impact to the cutting power of drill bit and the stable and uniform of iron mouth pore passage diameter.The blade of drill bit can prolong the lifetime of blade before Tie Kou opens than length, improve drill bit cutting power,, to keep more deep-seated to put the iron mouth pore passage bore constant.But the long distortion power that will increase drilling rod of blade, the drill bit angle of throat fractures easily.Sword face shape is more flat, influences the cutting speed of drill bit, otherwise as then can shorten sword face lifetime because of high temperature wear than point.Therefore the shape and structure of drill bit wants rationally advanced, and size is suitable.
(2) cooling to the working temperature that reduces drill bit, keep drill bit near mud drum least significant end (when drilling through, about 1100 ℃ of temperature) time, still have good thermohardening, guarantee the inside and outside aperture of iron mouth passage consistent be very important.The cooling performance of drill bit is influenced by the cooling water inflow and the type of cooling mainly.In drilling process, drill bit medium pore canal blowing air plays the effect of purging break flour, certain cooling effect is arranged simultaneously, but cooling power is lower, needs to add in addition the suitable quantity of water reinforcement and cools off.Cooling fog also should be able to make drill bit integral body can both obtain fine cooling except that the chip that should successfully purge out in the duct.So the design in the purging of drill bit, cooling duct will be optimized rationally.
(3) except that shape and structure rationally, drill bit material also must have high rigidity, high thermohardening is higher high temperature wear resistant performance.Blast furnace open hole needs quality-guarantee, and one time the iron mouth is not held successfully, not only influences conditions of blast furnace, and if unfavorable conditions such as iron mouth, leakage iron mouth occur oozing, can influence the later maintenance of this iron mouth, recover normal relatively difficulty, and the time is long, and is very unfavorable to safeguarding sidewall.So the iron mouth is once just opened as far as possible, opening can use 2 drilling rods at need, but maximum 3 drilling rods are opened 2 iron mouths.From efficient, economic angle, drill bit, drilling rod are used as the one-time consumption product for good, so its Material Selection to consider that material cost should be lower, complete processing is simple as far as possible.
A kind of blast furnace iron notch opening machine bit of the present invention comprises pedestal, at least 3 pieces of angle of throats; The center has ventilating pit on the pedestal; Angle of throat is distributed on the pedestal: described angle of throat head is that drill bit outer rim height is 13～16mm to the centroclinal ladder structure of pedestal.
Further, have the side air flue on the pedestal between described each angle of throat, this side air flue is connected with center roof vent, and with center roof vent α at angle.
The angle [alpha] of described angle of throat side air flue and center roof vent is 40 °～80 °, is preferably 60 °～70 °.
Described angle of throat head is β at angle, and angle beta is 30 °～40 °.
The trapezoidal top width t of described angle of throat is 8～10mm, and bottom width T is 25～28mm.
The drill bit pedestal adopts plain carbon stool, and angle of throat forms with the Wimet scolder built-up welding of tungstenic, cobalt element.
The manufacture method of blast furnace iron notch opening machine bit of the present invention comprises the steps:
Casting drill bit pedestal, with the plain carbon stool casting, ventilating pit is left at the center, and the position between each angle of throat pedestal is established the side air flue laterally at a certain angle, and is communicated with center roof vent;
Scantlings of the structure forms every piece of angle of throat with the carbide electrode built-up welding that contains W, Co composition on request on the drill bit pedestal; Welding rod is conventional carbide electrode.
Described components of welding electrode carries out trace adjustment by adding compositions such as 0.05%～0.1%Fe base or Co base WC, SiC, the folding strength and the toughness of the angle of throat of built-up welding formation is significantly improved, and further improved the high temperature wear resistant performance of drill bit.
The invention has the beneficial effects as follows:
Drill bit angle of throat physical dimension is long, the cutting face width, and does not rupture; Opening speed is fast, and the time is short, can reach opening 100% 1 time.
Pedestal is offered the side air flue on the basis of central airway, in drilling process, cooling fog also should be able to make drill bit head and side periphery thereof all fully be cooled off except that the chip that should successfully purge out in the duct, and drill bit integral body can both obtain fine cooling;
The bottom size choose reasonable of the trapezoidal angle of throat of drill bit makes the space between each angle of throat enough, is beneficial to the unobstructed discharge of accelerating powder in the opening drilling process, and is unlikely to block or block drilling rod;
The angle of throat on drill bit pedestal and top adopts differing materials and complete processing manufacturing respectively.The drill bit pedestal is cast with plain carbon stool, and angle of throat forms with the carbide electrode built-up welding that contains W, Co composition.After finishing, the whole manufacturing of drill bit, do not need thermal treatment without mechanical workout.Make that selection is easy to be easy to get, purchase cost is lower, and manufacturing processed is very simple, the production efficiency height;
Drill bit angle of throat face of tool is longer, but adjusts components of welding electrode (adding compositions such as Fe base or Co base WC, SiC) by trace, the folding strength of angle of throat and toughness is significantly improved, and further improved the high temperature wear resistant performance of drill bit, frangibility not during use.Bit cutting speeds up, and the angle of throat retention time prolongs, and can guarantee the slickness of iron mouth pore passage inwall.
Description of drawings
Fig. 1 is the structural representation of existing drill bit;
Fig. 2 is the left view of Fig. 1;
Fig. 3 is the structural representation of drill bit of the present invention;
Fig. 4 is the vertical view of Fig. 3.
Embodiment
Referring to Fig. 3, Fig. 4, blast furnace iron notch opening machine bit of the present invention comprises 3,3 pieces of angle of throats 5 of pedestal; The center has φ 12.5mm ventilating pit 2 on the pedestal 3; 3 pieces of angle of throats 5 become 120 ° (as with 4 pieces of angle of throats, then becoming 90 ° of layouts) evenly to arrange on drill bit pedestal 3; Described angle of throat 5 heads are that drill bit outer rim height h is 13～16mm to the ladder structure of center roof vent 2 inclinations (drill bit central axis inclination); Have side air flue 4 on the pedestal 3 between described each angle of throat 5, this side air flue 4 is connected with center roof vent 2, and with 2 one-tenth 60 ° of angle [alpha] of center roof vent, bore φ 8～10mm; Angle of throat 5 heads are β at angle, and angle beta is 45 °; Described angle of throat 5 trapezoidal top width t are 8mm, and bottom width T is 25mm.
The straight tube linkage section 1 of certain-length is left in drill bit pedestal 3 bottoms, and linkage section 1 is threading not, during use and drilling rod directly be welded to connect.
Drill bit outer rim latus rectum can change in φ 40～φ 60 plurality of specifications, is suitable for all kinds of volumetrical blast furnaces, has general versatility.
The manufacture method of blast furnace iron notch opening machine bit of the present invention, the drill bit pedestal is cast with plain carbon stool, and ventilating pit is left at the center, and the position between each angle of throat pedestal is established the side air flue laterally at a certain angle, and is communicated with center roof vent; Scantlings of the structure on request on the drill bit pedestal is used argon arc welding method, and with the carbide electrode that contains W, Co composition, built-up welding forms every piece of angle of throat on the drill bit pedestal; Adjust components of welding electrode by trace, add compositions such as 0.05%Fe base or Co base WC, SiC, the folding strength of angle of throat and toughness are significantly improved, and further improved the high temperature wear resistant performance of drill bit.
The present invention compares through on-the-spot use of blast furnace, at iron port gun mud sintering time 130～170 minutes, stemming composition and Si
3N
4Under constant, identical taphole drilling machine operation of content and the water-flowing amount condition, for the iron mouth degree of depth of 4.0m, the average opening speed of drill bit of the present invention reaches 3.1cm/s, opening time 2～2.5 minutes, than the about fast 0.4～0.6cm/s of existing drill bit, one time the opening success ratio reaches 100%; And the opening process stabilization, speed is fast, is subjected to resistance little, and row's powder is unobstructed, and the iron mouth does not have splash in the process of tapping a blast furnace.The iron mouth is mainly opened by grinding rather than by rapping, helps the maintenance of iron mouth mud drum and cupola well sidewall liner.
Claims (10)
1. blast furnace iron notch opening machine bit comprises
Pedestal, center has ventilating pit on it;
At least 3 pieces of angle of throats are distributed on the pedestal; It is characterized in that: described angle of throat head
For to the centroclinal ladder structure of pedestal, drill bit outer rim height is 13～16mm.
2. blast furnace iron notch opening machine bit as claimed in claim 1 is characterized in that: have the side air flue on the pedestal between described each angle of throat, this side air flue is connected with center roof vent, and with center roof vent α at angle.
3. blast furnace iron notch opening machine bit as claimed in claim 2 is characterized in that: the angle [alpha] of described angle of throat side air flue and center roof vent is 40 °～80 °.
4. blast furnace iron notch opening machine bit as claimed in claim 2 is characterized in that: the angle [alpha] of described angle of throat side air flue and center roof vent is preferably 60 °～70 °.
5. blast furnace iron notch opening machine bit as claimed in claim 1 or 2 is characterized in that: described angle of throat head is β at angle, and angle beta is 30 °～40 °.
6. blast furnace iron notch opening machine bit as claimed in claim 1 or 2 is characterized in that: the trapezoidal top width t of described angle of throat is 8～10mm, and bottom width T is 25～28mm.
7. blast furnace iron notch opening machine bit as claimed in claim 1 is characterized in that: the drill bit pedestal adopts straight carbon steel, and angle of throat forms with the Wimet scolder built-up welding of tungstenic, brill element.
8. the manufacture method of blast furnace iron notch opening machine bit is characterized in that, comprises the steps:
The casting of drill bit pedestal, with the plain carbon stool casting, ventilating pit is left at the center, and the position between each angle of throat pedestal is established the side air flue laterally at a certain angle, and is communicated with center roof vent;
Scantlings of the structure forms every piece of angle of throat with the carbide electrode built-up welding that contains W, Co composition on request on the drill bit pedestal.
9. the manufacture method of blast furnace iron notch opening machine bit as claimed in claim 8 is characterized in that: described drill bit pedestal is cast with plain carbon stool.
10. the manufacture method of blast furnace iron notch opening machine bit as claimed in claim 8, it is characterized in that: described components of welding electrode is by adding compositions such as 0.05%～0.1%Fe base or Co base WC, SiC, carry out trace adjustment, the folding strength and the toughness of the angle of throat of built-up welding formation are significantly improved, and further improved the high temperature wear resistant performance of drill bit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200410024854XA CN100467617C (en) | 2004-05-28 | 2004-05-28 | Drill bit for taphole of blast furnace and method for producing same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200410024854XA CN100467617C (en) | 2004-05-28 | 2004-05-28 | Drill bit for taphole of blast furnace and method for producing same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1704481A true CN1704481A (en) | 2005-12-07 |
| CN100467617C CN100467617C (en) | 2009-03-11 |
Family
ID=35576461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB200410024854XA Expired - Lifetime CN100467617C (en) | 2004-05-28 | 2004-05-28 | Drill bit for taphole of blast furnace and method for producing same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100467617C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110666386A (en) * | 2019-10-17 | 2020-01-10 | 沈阳理工大学 | Research method for improving performance parameters of argon arc welding surfacing process |
| CN113523742A (en) * | 2021-07-05 | 2021-10-22 | 桂林市中锐特机械制造有限责任公司 | Manufacturing method of T-shaped wear-resistant layer drill bit for blast furnace tapping |
-
2004
- 2004-05-28 CN CNB200410024854XA patent/CN100467617C/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110666386A (en) * | 2019-10-17 | 2020-01-10 | 沈阳理工大学 | Research method for improving performance parameters of argon arc welding surfacing process |
| CN110666386B (en) * | 2019-10-17 | 2021-05-25 | 沈阳理工大学 | Research method for improving performance parameters of argon arc welding surfacing process |
| CN113523742A (en) * | 2021-07-05 | 2021-10-22 | 桂林市中锐特机械制造有限责任公司 | Manufacturing method of T-shaped wear-resistant layer drill bit for blast furnace tapping |
| CN113523742B (en) * | 2021-07-05 | 2022-07-15 | 桂林市中锐特机械制造有限责任公司 | Manufacturing method of T-shaped wear-resistant layer drill bit for blast furnace tapping |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100467617C (en) | 2009-03-11 |
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Granted publication date: 20090311 |