CN100535170C - Annealing method for high-speed steel cold-drawing wire products - Google Patents
Annealing method for high-speed steel cold-drawing wire products Download PDFInfo
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- CN100535170C CN100535170C CNB2006101475361A CN200610147536A CN100535170C CN 100535170 C CN100535170 C CN 100535170C CN B2006101475361 A CNB2006101475361 A CN B2006101475361A CN 200610147536 A CN200610147536 A CN 200610147536A CN 100535170 C CN100535170 C CN 100535170C
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Abstract
The invention discloses annealing method for high speed tool steel cold drawn steel wire finished products, solving the problems of low annealing efficiency, large energy consumption, etc. The mass percentage compositions of a high speed tool steel cold drawn steel wire rod are: 0.80 to 0.90 percent by mass of C, less than or equal to 0.40 percent by mass of Mn, less than or equal to 0.40 percent by mass of Si, 3.80 to 4.40 percent by mass of Cr, 1.75 to 2.20 percent by mass of V, 5.50 to 6.75 percent by mass of W, 4.50 to 5.50 percent by mass of Mo, less than or equal to 0.030 percent by mass of P, less than or equal to 0.030 percent by mass of S, and the balance Fe. The method comprises the following steps of: 1) annealing of finished product, in which the rod is placed into a strong-convection annealing furnace, a heating mantle is cover on the furnace, and then nitrogen purging is carried out to replace the air in the furnace with nitrogen which is used for atmosphere protection during the annealing process; 2) heating the product with the furnace to a temperature of between 710 and 750 DEG C and keeping the temperature for 4 to 8 hours, covering the heating mantle, and then cooling down the furnace to a temperature below 650 DEG C, at a cooling speed less than or equal to 30 DEG C per hour, and removing the heating mantle; 4) covering a cooling mantle to cool down the product to a temperature below 140 DEGC at a cooling speed more than 100 DEG C per hour. The invention is high in annealing efficiency, thereby greatly reducing the energy consumption.
Description
Technical field
The present invention relates to metallic substance thermal treatment, particularly a kind of annealing method for high-speed steel cold-drawing wire products.
Background technology
Rapid tool steel such as W6Mo5Cr4V2 are the representative trades mark in the rapid tool steel, and because of having good red hardness, hot hardness, toughness and wear resistance, High Speed Steel Wire is mainly used in high speed cutting cutter and drill bit.The main production flow process of rapid tool steel drawn wire is: hot-roll annealing dish circle-pickling coating-drawing-process annealing-pickling, coating-drawing (intercycle annealing and drawing passes are up to finished product)-finished products-rectify by (mill)-the check warehouse-in.Wherein, finished products is last one thermal treatment during the rapid tool steel drawn wire is produced, and purpose is the scope that hardness is reduced to standard-required, satisfies the needs that the user shapes; And prevent the oxidation and decarbonization on surface, rapid tool steel is owing to carbon content and contain molybdenum amount height, and decarburization susceptibility is big, and Heating temperature in the heat treatment process and heating atmosphere have material impact to the decarburization of steel wire.Therefore, finished products is to be directly connected to product final delivery performance and surface quality, is indispensable critical process.
Existing finished products mostly adopts the rectangle bell furnace, and one is the strong convection annealing furnace (size is diameter 3m, height 3.7m) of 26.2 cubic metres of useful volumes.Consider the output of rapid tool steel drawn wire finished product, in the prior art, the rapid tool steel drawn wire finished product of our company is that (size is high 1.8m for rectangle bell furnace 19.8 cubic metres of useful volumes, length 5.5m, width 2m) carry out annealed, two sides adopt the Sweet natural gas burner to heat along its length.In order to prevent oxidation of steel wire finished surface and decarburization, coil of wire circle after cold drawn be contained in the height 1.3m, chassis diameter 0.9m bin on after, pack into inside diameter 1.5m, the height 1.6m metal bucket in, adding a cover the back anneals with being placed in behind the toner seal in the rectangle bell furnace, put into an amount of carbon dust in the bucket in advance and improve carbon potential, prevent Steel Wire Surface decarburization in the annealing process.Each table can be put 3 metal buckets, and average charge amount is 1 ton in each metal bucket, and therefore the average charge amount of actual every stove is 3 tons, and the annealing cycle is 15 hours.
The weak point that adopts above-mentioned existing rectangle bell furnace mode to carry out rapid tool steel drawn wire finished products is:
1) because the heat transfer rate of heating of barrelling annealing way is slow, for guaranteeing the even of finished products hardness, take the finished product of three kinds of annealing process: 〉=7mm to adopt 750 ℃ of annealing processs by the specification difference, φ 7～〉=finished product of 4mm adopts 730 ℃ of annealing processs, the finished product of＜4mm adopts 710 ℃ of annealing processs, the technology more complicated, the different size material must divide furnace annealing, has influenced production schedule to a certain extent.
2) batch causes energy consumption per ton steel quite high very little, and average ton steel gas consumption reaches 298m
3, be higher than the ton steel Sweet natural gas performance assessment criteria of this enterprises far away.
The bin that adopts during 3) owing to the drawing of rapid tool steel steel wire is higher, therefore needs to translate on the short bin before the annealing, so that barrelling also will be carried out barrelling and unload bucket before and after the annealing, complex operation step, production efficiency are very low;
Summary of the invention
The purpose of this invention is to provide a kind of annealing method for high-speed steel cold-drawing wire products, the annealing efficiency height reduces energy consumption and operation easier significantly, simplifies technology simultaneously, guarantees production schedule, and, can realize piecing together furnace annealing with other steel grades.
For achieving the above object, technical scheme of the present invention is,
A kind of annealing method for high-speed steel cold-drawing wire products, it comprises the steps:
1) the composition quality per-cent of rapid tool steel drawn wire dish circle is: C 0.80～0.90, Mn≤0.40, Si≤0.40, Cr 3.80～4.40, V 1.75～2.20, W 5.50～6.75, Mo 4.50～5.50, P≤0.030, S≤0.030, all the other are iron;
2) finished products;
To coil in the round strong convection annealing furnace of packing into, add a cover heating mantles, carry out nitrogen purging; Adopt nitrogen to carry out atmosphere protection in the annealing process;
3) the dish circle is warmed up to 710～750 ℃ with stove, is incubated 4-8 hour, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, removes heating mantles subsequently;
4) cover cooling cowl, be cooled to 140 ℃ of following temperature with the speed of cooling of 〉=100 ℃/h and come out of the stove.
Further, carry out the purity of the nitrogen of atmosphere protection in the annealing process: dew point≤-60 ℃, oxygen level≤5ppm.
Again, nitrogen purging technology is: gas flow 20～50m
3/ h purged 3～7 hours.
Nitrogen purging technology is: gas flow 10～20m
3/ h purged 1～3 hour.
In the round strong convection annealing furnace of packing into of dish, charging method is two layers of 3 buttress, and when bin was put, certain space was reserved in the centre, and the little bin (1～2) that rapid tool steel is adorned is placed in the vacant position of table.
Method for annealing of the present invention is to anneal in the strong convection annealing furnace, and the strong convection annealing furnace can adopt the nitrogen behind the purifying to carry out protective atmosphere annealing, can effectively prevent the Steel Wire Surface oxidation and decarbonization; Stove seat bottom adopts the base ring flow fan of 55KW to carry out the circulation of furnace gas, and the temperature homogeneity of the whole burner hearth of holding stage can be controlled in 10 ℃, meets the required requirement of rapid tool steel finished products fully; And technology is simplified than prior art, and operation easier reduces; Simultaneously, take suitable charging mode, reduce energy consumption significantly.
Be warmed up to 710～750 ℃ of insulations 4-8 hour with stove, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, remove heating mantles subsequently, cover cooling cowl, be cooled to 140 ℃ of following temperature with speed of cooling and come out of the stove faster than 100 ℃/h.Adopt the nitrogen through purification process to carry out atmosphere protection in the annealing process, the purity requirement of nitrogen reaches: dew point≤-60 ℃, oxygen level≤5ppm is to prevent the oxidation of steel wire finished surface, decarburization.Nitrogen purging technology is: 20～50m
3/ h purged 3～7 hours; 10～20m
3/ h purged 1～3 hour.
The annealing useful space of strong convection stove is: diameter 3m, height 3.7m.Charging method is two layers of 3 buttress, and every furnace charge can be adorned 6 volume deep bid circles, and batch reaches the 12-14 ton, mainly adapts to the kind annealing needs in enormous quantities that bearing steel and carbon close the knot steel.Rapid tool steel drawn wire annealed characteristics are that small batch is uninterruptedly produced, each weight of rolling batch is about 1 ton, therefore the rapid tool steel drawn wire should take to piece together with other normal steels the annealing way of stoves at the strong convection stove, improves annealing efficiency, guarantees production schedule.
The bin of the charging of rapid tool steel drawn wire is the little bin of common material, internal diameter is in 500mm, and the skid bed internal diameter of the existing dress of strong convection stove deep bid circle is 600-800mm, can't be general, if the high temperature steel bin that special making can stack, then expense is very high.At the actual charging situation of present strong convection stove, when the bin of piecing together the stove steel grade is put, the position is slightly adjusted, certain space is reserved in the centre, and the little bin (1～2) that rapid tool steel is adorned is placed in the vacant position of table.Like this, it is more convenient to take on stove, also need not make bin specially.
The condition of production according to the scene, annealing amount maximum be the cold drawn Pan Yuan of bearing steel, because bearing steel recrystallization annealing wider range, generally between 650～750 ℃, all can satisfy the annealing requirement, piece together with it to burn and on technology, have feasibility, and because its turnout is big, it is the most convenient to take burning.The annealing characteristics of comprehensive strong convection kind and rapid tool steel annealing requirement have been formulated the special use of the cold drawn dish circle of rapid tool steel drawn wire finished product and bearing steel and have been pieced together furnace annealing technology, and this technology also is fit to rapid tool steel finished products amount and anneals separately for a long time.
Beneficial effect of the present invention
Compare with prior art, the present invention has following advantage:
1) owing to adopts the strong convection thermal cycling of table blower fan in the annealing process, the homogeneity of rate of heating and furnace temperature has had obvious improvement than existing technology, the annealing process that adopts is applicable to the same furnace annealing of all size, can fully eliminate the work hardening that produces in the steel wire cold working process equally, reduce hardness and improve plasticity, and make technology obtain simplifying.
2) heating efficiency of strong convection stove and sealing property all obviously are better than the rectangle bell furnace, and under average batch condition, ton steel gas consumption is 13.4% of a current technology only, and energy-saving effect is remarkable.
3) bin that adopts during the drawing of rapid tool steel steel wire can directly lift table, need not translate on the short bin before the annealing again, the operation steps of having avoided tilting trestle, the barrelling of existing process using and having unloaded barrel, and production efficiency is largely increased.
4) adopt nitrogen protection annealed steel wire surface quality also to be better than or to be equal to existing technology barrelling quality level.
Description of drawings
Fig. 1 is an annealing process synoptic diagram of the present invention.
Embodiment
The composition quality per-cent of rapid tool steel drawn wire dish of the present invention circle is: C0.80～0.90, Mn≤0.40, Si≤0.40, Cr 3.80～4.40, V 1.75～2.20, W 5.50～6.75, Mo 4.50～5.50, P≤0.030, S≤0.030, all the other are iron; By smelting, cast, be rolled into the dish circle; Annealing, cold drawn, annealing again, cold drawn circulation is until finished products again.
Referring to Fig. 1, it is depicted as annealing process of the present invention.
Be warmed up to 710～750 ℃ of insulations 4-8 hour with stove, subsequently after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h; Being cooled to 140 ℃ of following temperature with the speed of cooling faster than 100 ℃/h again comes out of the stove.
Embodiment 1,
To coil in the round strong convection annealing furnace of packing into, add a cover heating mantles, carry out nitrogen purging; Adopt nitrogen to carry out atmosphere protection in the annealing process; Be warmed up to 710～730 ℃ of insulations 6-8 hour with stove, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, remove heating mantles subsequently, adopt cooling cowl to be cooled to 140 ℃ of following temperature and come out of the stove with speed of cooling faster than 100 ℃/h.Adopt purification nitrogen to carry out atmosphere protection in the annealing process, the dew point of nitrogen≤-60 ℃, oxygen level≤5ppm prevents finished surface oxidation, decarburization.Nitrogen purging technology is: 30～40m
3/ h purged 3～4 hours; 10～20m
3/ h purged 1～2 hour.
Charging method: at the actual charging situation of present strong convection stove, when the bin of piecing together the stove steel grade is put, the position is slightly adjusted, certain space is reserved in the centre, and the little bin (1～2) that rapid tool steel is adorned is placed in the vacant position of table.It is very convenient to take on stove, and saves the high cost of making heat-resisting special-purpose bin.
Embodiment 2
To coil in the round strong convection annealing furnace of packing into, add a cover heating mantles, carry out nitrogen purging; Adopt nitrogen to carry out atmosphere protection in the annealing process; Be warmed up to 720～740 ℃ of ℃ of insulations 5-7 hour with stove, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, remove heating mantles subsequently, adopt cooling cowl to be cooled to 140 ℃ of following temperature and come out of the stove with speed of cooling faster than 100 ℃/h.Adopt purification nitrogen to carry out atmosphere protection in the annealing process, the dew point of nitrogen≤-60 ℃, oxygen level≤5ppm prevents finished surface oxidation, decarburization.Nitrogen purging technology is: 30～40m
3/ h purged 4～5 hours; 10～20m
3/ h purged 2～3 hours.
Embodiment 3
To coil in the round strong convection annealing furnace of packing into, add a cover heating mantles, carry out nitrogen purging; Adopt nitrogen to carry out atmosphere protection in the annealing process; Be warmed up to 730～750 ℃ of insulations 4-6 hour with stove, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, remove heating mantles subsequently, adopt cooling cowl to be cooled to 140 ℃ of following temperature and come out of the stove with speed of cooling faster than 100 ℃/h.Adopt purification nitrogen to carry out atmosphere protection in the annealing process, the dew point of nitrogen≤-60 ℃, oxygen level≤5ppm prevents finished surface oxidation, decarburization.Nitrogen purging technology is: 35～50m
3/ h purged 5～6 hours; 10～20m
3/ h purged 2～3 hours.
Take method for annealing of the present invention, the operation of rapid tool steel steel wire finished products loading and unloading material is simplified greatly, annealing quality is guaranteed that well the gas consumption of ton steel has had very significantly decline simultaneously, adapts to the active demand that reduces energy consumption in the current industrial production fully.
Implementing the tracking situation shows, 10 specification W6Mo5Cr4V2 rapid tool steel steel wire finished products of φ 3.3～6.7mm in conventional the production, pursue batch assembly furnace annealing by new mode, annealing maximum hardness HB252, lowest hardness HB221, average hardness is 234.7, satisfies the HB207-255 scope (seeing Table 1) of standard-required fully, and the annealing effect is more satisfactory.The finished product decarburization is all in 0.03mm, and is consistent with existing barrelling annealing level, satisfies the national standard requirement.And cold drawn the coiling of the bearing steel of piecing together furnace annealing also satisfied back road drawing and end properties requirement fully.
W6Mo5Cr4V2 rapid tool steel steel wire all size finished product delivery hardness after table 1 the present invention anneals
| Trimmed size | 6.7 mm | 6.6 mm | 6.5 mm | 6.3 mm | 6.0 mm | 4.7 mm | 4.5 mm | 4.3 mm | 3.6 mm | 3.3 mm |
| Annealing hardness | 234 ～ 239 | 234 ～ 239 | 229 ～ 239 | 229 ～ 239 | 229 ～ 234 | 221 ～ 232 | 221 ～ 232 | 244 ～ 252 | 232 ～ 237 | 232 ～ 244 |
The batch that strong convection is pieced together stove production can reach about 13 tons, and the Sweet natural gas mean consumption after annealing way improves is 40m
3/ t, and existing barrelling annealed gas consumption reaches 298m
3/ t, gas consumption have had and have declined to a great extent.With at present, 20 tons of calculating of the average monthly output of rapid tool steel drawn wire: originally=(298-40) m falls in a year Sweet natural gas
3/ t * 2.26 yuan/m
3* 20 tons/month * 12 months=140,000 yuan.
Claims (5)
1. annealing method for high-speed steel cold-drawing wire products, it comprises the steps:
1) the composition quality per-cent of rapid tool steel drawn wire dish circle is: C 0.80～0.90, Mn≤0.40, Si≤0.40, Cr 3.80～4.40, V 1.75～2.20, W 5.50～6.75, Mo4.50～5.50, P≤0.030, S≤0.030, all the other are iron;
2) finished products
To coil in the round strong convection annealing furnace of packing into, add a cover heating mantles, carry out nitrogen purging, use the nitrogen replacement furnace air; Adopt nitrogen to carry out atmosphere in the annealing process and protect expansion;
3) be warmed up to 710～750 ℃ of insulations 4-8 hour with stove, after speed of cooling slow cooling to the 650 ℃ following temperature with≤30 ℃/h, remove heating mantles subsequently;
4) cover cooling cowl, be cooled to 140 ℃ of following temperature with speed of cooling and come out of the stove faster than 100 ℃/h.
2. annealing method for high-speed steel cold-drawing wire products as claimed in claim 1 is characterized in that, carries out the purity of the nitrogen of atmosphere protection in the annealing process: dew point≤-60 ℃, oxygen level≤5ppm.
3. annealing method for high-speed steel cold-drawing wire products as claimed in claim 1 is characterized in that step 2) in the gas flow 20～50m of nitrogen purging
3/ h purged 3～7 hours.
4. annealing method for high-speed steel cold-drawing wire products as claimed in claim 1 is characterized in that step 2) in carry out nitrogen purging once more, gas flow 10～20m
3/ h purged 1～3 hour.
5. annealing method for high-speed steel cold-drawing wire products as claimed in claim 1, it is characterized in that, the cold drawn dish circle of bearing steel is packed in the strong convection annealing furnace, charging method is two layers of 3 buttress, when its bin is put, slot milling in the middle of table is placed in this locus of table with the round bin of dress high-speed tool steel disk, pieces together furnace annealing with the cold drawn dish circle of bearing steel.
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| CNB2006101475361A CN100535170C (en) | 2006-12-20 | 2006-12-20 | Annealing method for high-speed steel cold-drawing wire products |
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| CN100535170C true CN100535170C (en) | 2009-09-02 |
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| CN104480267B (en) * | 2014-12-23 | 2017-01-18 | 淮南泰隆机械制造有限公司 | Technology for removing oxide scale on surface of steel wire |
| CN104593580B (en) * | 2014-12-24 | 2017-05-03 | 河冶科技股份有限公司 | Method for preventing annealing carburization of high-speed tool steel cold-drawn steel wire |
| CN106086329A (en) * | 2016-07-21 | 2016-11-09 | 广东长盈精密技术有限公司 | Reduce technique and the mobile phone center of steel part hardness |
| WO2018107473A1 (en) * | 2016-12-16 | 2018-06-21 | 蔡赛 | Annealing and heat treatment method for steel wire |
| CN109680131A (en) * | 2019-02-28 | 2019-04-26 | 石家庄市金峰特钢制品有限公司 | A kind of Annealing Protection method of high-speed steel steel wire |
| CN110055381B (en) * | 2019-04-29 | 2020-08-07 | 武钢集团昆明钢铁股份有限公司 | Nitrogen protection annealing process of light-weight tool and die steel |
| CN112553420A (en) * | 2020-12-02 | 2021-03-26 | 太仓富勒姆纳米新材料科技有限公司 | Strong-convection spheroidizing annealing process for rivets for automobile bearing retainer |
| CN114292996B (en) * | 2021-11-26 | 2023-12-08 | 铃木加普腾钢丝（苏州）有限公司 | Process for heat treating steel wire oxide layer |
| CN115109987A (en) * | 2022-07-27 | 2022-09-27 | 江西省科学院应用物理研究所 | Method for regulating and controlling carbide precipitation in high-speed steel and high-performance high-speed steel |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU916582A1 (en) * | 1980-08-11 | 1982-03-30 | Avenir N Popandopulo | High speed steel composition |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU916582A1 (en) * | 1980-08-11 | 1982-03-30 | Avenir N Popandopulo | High speed steel composition |
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