CN103966503B - High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof - Google Patents

High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof Download PDF

Info

Publication number
CN103966503B
CN103966503B CN201410213192.4A CN201410213192A CN103966503B CN 103966503 B CN103966503 B CN 103966503B CN 201410213192 A CN201410213192 A CN 201410213192A CN 103966503 B CN103966503 B CN 103966503B
Authority
CN
China
Prior art keywords
content
molten steel
steel
control
less
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.)
Active
Application number
CN201410213192.4A
Other languages
Chinese (zh)
Other versions
CN103966503A (en
Inventor
刘春伟
王中学
纪进立
宋玉卿
霍喜伟
王刚
袁鹏举
孙晓庆
赵新华
方金林
孔令坤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Laiwu Iron and Steel Group Co Ltd
Original Assignee
Laiwu Iron and Steel Group Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Laiwu Iron and Steel Group Co Ltd filed Critical Laiwu Iron and Steel Group Co Ltd
Priority to CN201410213192.4A priority Critical patent/CN103966503B/en
Publication of CN103966503A publication Critical patent/CN103966503A/en
Application granted granted Critical
Publication of CN103966503B publication Critical patent/CN103966503B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The invention discloses high-strength H-shaped steel for a mast of a forklift truck and a manufacturing method thereof. The manufacturing method comprises the following steps: (a) obtaining primary molten iron; (b) adopting the converter primary molten iron; (c) adjusting the content of V in the molten iron to 0.05wt%-0.1wt% and the content of Ni in the molten iron to 0.1wt%-0.2wt%, and when the content of P in the molten iron does not exceed 0.010wt%, tapping to steel ladles; (d) adjusting the content of Si, Mn, Nb and O in the molten iron in a process of tapping to the steel ladles; (e) adjusting the content of C and O in the molten iron in a steel ladle refining furnace; (f) carrying out continuous casting on the molten iron so as to obtain a continuous casting blank; and (g) roughly rolling, precisely rolling and straightening the continuous casting blank, thus obtaining the high-strength H-shaped steel for the mast of the forklift truck.

Description

Forklift door frame high intensity H type steel and its manufacture method
Technical field
The present invention relates to a kind of door frame steel and its manufacture method, in particular it relates to a kind of forklift door frame is used High intensity H type steel and its manufacture method.
Background technology
Forklift door frame hangs on the drive axle in front of fork truck, fork truck goods is carried out insert take lifting during, fork truck Door frame can produce very big tilting moment with front driving axle for the centre of moment, and it is high-strength that this tilting moment requires forklift door frame steel to have Degree and high tenacity.
The intensity rank of the forklift door frame shaped steel of prior art is usually 335mpa and 400mpa, only small part product Can reach 420mpa and 475mpa.Usually require that intensity and the toughness of forklift door frame steel are high as much as possible.
Content of the invention
It is an object of the invention to overcoming above-mentioned technical problem, there is provided a kind of forklift door frame with high intensity H type steel and its Manufacture method.
The chemical composition of the forklift door frame high intensity H type steel according to the present invention is: the c of 0.24wt%~0.30wt%, The mn of si, 1.2wt% of 0.20wt%~0.40wt%~1.5wt%, less than 0.020wt% p, be less than Ni, 0.025wt% of v, 0.1wt% of s, 0.05wt% of 0.010wt%~0.1wt%~0.2wt%~0.05wt%'s Nb, balance of ferrum and inevitable impurity.
Forklift door frame according to the present invention manufacture method of high intensity H type steel, comprises the following steps: (a) just smelts iron water; (b) when the s content of molten iron is less than 0.01wt%, using making steel water at the beginning of converter;(c) adjust molten steel v content be 0.05wt%~0.1wt%, ni content are 0.1wt%~0.2wt%, and are less than 0.010wt% in the p content of molten steel When, to ladle tapping;D (), during tapping to ladle, the si content of adjustment molten steel is 0.20wt%~0.38wt%, mn Content is 1.2wt%~1.5wt%, nb content is 0.025wt%~0.05wt%, o content is less than 50ppm;E () is in steel The c content adjusting molten steel in bag refining furnace is 0.24wt%~0.30wt%, o content is less than 10ppm;F () is carried out to molten steel Continuous casting, to obtain continuous-cast blank;G () carries out roughing, finish rolling and aligning to continuous-cast blank, thus obtaining forklift door frame with high-strength Degree H type steel.
According to the exemplary embodiment of the present invention, in step (b), water can be made steel using at the beginning of top and bottom combined blown converter, and The steel scrap that sulfur content is less than 0.01wt% can be added in molten steel.
According to the exemplary embodiment of the present invention, in step (b), can be controlled using the addition nitrogen-vanadium alloy in molten steel The v content of molten steel processed, can control the ni content of molten steel using the addition nickel plate in molten steel.
According to the exemplary embodiment of the present invention, in step (d), the impact of steel stream can be directed at when molten steel goes out to 1/4 Area is uniformly added into the content to control the alloying element of molten steel for the alloy adjusting molten steel composition, until adding when molten steel goes out to 3/4, Wherein it is possible to using adding silicomangan to control the si content of molten steel in molten steel, add high carbon ferromanganese alloy to control steel The mn content of water, adds ferrocolumbium to control the nb content of molten steel, adds aluminum-manganese-iron alloy to control the o content of molten steel.
According to the exemplary embodiment of the present invention, step (e) is additionally may included in the composition in lf purifier to molten steel It is finely adjusted.
According to the exemplary embodiment of the present invention, in step (e), can stir, in refining process whole argon bottom-blowing Argon pressure can control argon pressure before 90nl/min~150nl/min, outbound can control 30nl/min~ 80nl/min, argon blowing time can be no less than 11min, can be using at least one in Acetylenogen. or carborundum by before outbound Slag is adjusted to white slag or yellowish-white slag, can be using the o's of at least one control outbound molten steel in Si-Ca-Ba, silicomanganese or ferrosilicon Content is less than 10ppm.
According to the exemplary embodiment of the present invention, in step (f), continuous casting can adopt molding casting, and pulling rate scope can To control in 0.80m/min~0.90m/min
According to the exemplary embodiment of the present invention, in step (g), roughing start rolling temperature controls 1050 DEG C~1150 DEG C, at 950 DEG C~1050 DEG C, finish rolling start rolling temperature controls at 900 DEG C~950 DEG C roughing finishing temperature control, finish rolling finish to gauge temperature Degree controls at 800 DEG C~850 DEG C.
Forklift door frame according to the present invention high intensity H type steel and its manufacture method, simple production process, by molten steel In the microalloying of v, nb, ni element make door frame steel have excellent intensity and impact flexibility.Additionally, the door frame of the present invention Also reduce the manufacturing cost of door frame steel with the low content of alloying element in steel.
Specific embodiment
Present invention is generally directed to forklift door frame with high intensity H type steel the problem in composition, smelting process, there is provided a kind of Forklift door frame high intensity H type steel and preparation method thereof.The forklift door frame that the method according to the invention is produced high intensity H type Steel has excellent intensity and impact flexibility.
Carry out the forklift door frame high intensity H type steel to the present invention below in conjunction with exemplary embodiment and its manufacture method is done Further describe.
The composition of the forklift door frame high intensity H type steel according to the present invention is: the c of 0.24wt%~0.30wt%, The mn of si, 1.2wt% of 0.20wt%~0.40wt%~1.5wt%, less than 0.020wt% p, be less than Ni, 0.025wt% of v, 0.1wt% of s, 0.05wt% of 0.010wt%~0.1wt%~0.2wt%~0.05wt%'s Nb, balance of ferrum and inevitable impurity.
Forklift door frame according to present invention high intensity H type steel, its composition characteristic is that the content of p, s, o is low, and v, ni, nb close The addition of gold is low, thus on the premise of ensureing that product has high intensity, realizing low cost and produce.The reason do so, exists In: in the prior art, for obtaining the product of high intensity, generally to realize alloy using a large amount of interpolation noble alloys such as nb, v strong Change, this situation can improve the production cost of product;And in the present invention, by reducing p, s content, improve Molten Steel Cleanliness, Reduce the content of the field trash in product, to be taken off eventually using at least one in cheap Si-Ca-Ba, silicomanganese and ferrosilicon meanwhile Oxygen, so that the forklift door frame of the present invention is less than 10ppm with the oxygen content of high intensity H type steel, produces low oxygen content with low cost Clean steel.In addition it is only necessary to add micro v, ni, nb alloy, you can ensureing that product has high intensity and HI high impact is tough Property on the premise of, simultaneously realize low cost produce.In addition, adding micro v, ni, nb alloy in the present invention, can thinning microstructure crystalline substance Grain, improves intensity and the toughness of steel, reduces superheated susceptivity and the temper brittleness of steel, and makes steel the production process with molding procedure Control simple.
The forklift door frame manufacture method with high intensity H type steel of the present invention is described below.
The manufacture method of the steel according to the present invention includes just smelting iron water, just steel-making water, lf stove (ladle refining furnace) refine, company Casting and rolling.
First, just smelt iron water in blast furnace, when the s content of molten iron is less than 0.010wt%, molten iron is blended into converter and enters Row just makes steel water.
Secondly, just steel-making water is carried out in top and bottom combined blown converter, the argon flow amount of argon bottom-blowing be 300nl/min~ 400nl/min, the oxygen flow of top blast oxygen is 3nm3/ min~4.5nm3/ min, finishing slag basicity controls below 3.0.Permissible Sulfur content is added to be less than the steel scrap of 0.01wt% during bessemerizing in molten steel, to reduce smelting cost, meanwhile, choosing Select the rising that the steel scrap that sulfur content is less than 0.01wt% can also avoid the sulfur content of molten steel.Additionally, steel scrap is also used as Reducing liquid steel temperature, the addition of described steel scrap can be 20kg/t to coolantSteel~40kg/tSteel.Can by VN alloy with And nickel plate is added in molten steel with furnace charge, the v content to control molten steel is 0.05wt%~0.10wt%, ni content is 0.1wt%~0.2wt%, when the p content of molten steel is less than 0.010wt%, to ladle tapping.
Then, during tapping to ladle, steel stream impact zone can be directed at when molten steel goes out to 1/4 and add adjustment steel The alloy of water constituent controlling the alloying element content of molten steel, including silicomangan being added in molten steel to control molten steel Si content is 0.20wt%~0.38wt%, high carbon ferromanganese Alloy can be added to control the mn content of molten steel in molten steel For 1.2wt%~1.5wt%, and ferrocolumbium can be added in molten steel to control the nb content of molten steel is 0.025wt% ~0.05wt%, can add the deoxidation treatment that aluminum-manganese-iron alloy carries out molten steel to control the oxygen content of molten steel not surpass in molten steel Cross 50ppm, and alloying element adds when molten steel goes out to 3/4.
According to one exemplary embodiment of the present invention, for adjust molten steel si content silicomangan and for controlling Mn is contained, molten steel can be absorbed by said process during component controlling in the aluminum-manganese-iron alloy of o content of molten steel Part mn, therefore, it can add high carbon ferromanganese alloy to adjust the mn content of the remainder in molten steel in molten steel, makes molten steel Mn content be 1.2wt%~1.5wt%.Additionally, during ladle refining process is carried out to molten steel, by molten steel At least one adding Si-Ca-Ba, silicomanganese and Antaciron carrys out deep deoxidation, enters due in this deoxidation process, having part si To in molten steel, therefore, in tapping process, the content of the si in molten steel is controlled to be less than 0.38wt%, to prevent deoxidation process In because the si in deoxidizer is absorbed by molten steel, the si content that increases molten steel makes it higher than 0.40wt%.When molten steel is in refine When the deoxidizer using during process includes silicomangan, for ensureing the mn content in molten steel, should be in the mistake of molten steel tapping The mn content of molten steel is controlled to be not higher than 1.4wt%, to avoid molten steel using silicomangan deoxidation in refining process in journey And the mn content increasing molten steel makes it more than 1.5wt%.
Next, lf refining treatment is carried out to the molten steel in ladle.Specifically, lf refining process is using whole BOTTOM ARGON BLOWING Gas agitating, the argon pressure in refining process can control argon pressure before 90nl/min~150nl/min, outbound can control System is no less than 11min in 30nl/min~80nl/min, argon blowing time.Calx can be added in molten steel to enter according to practical situation Row slag making it is possible to the slag before outbound is adjusted to by white slag or yellowish-white slag using at least one in Acetylenogen. or carborundum, And the retention time of yellowish-white slag or white slag is no less than 10min.Can be come using at least one in Si-Ca-Ba, silicomanganese or ferrosilicon The o content controlling molten steel is less than 10ppm, and by the c content that the addition carbon in molten steel adjusts molten steel can be 0.24wt%~0.30wt%.
When tapping to ladle, inevitably bring a certain amount of vessel slag into in ladle.Vessel slag phosphorus content is high, Under the effect of lf stove reducing atmosphere, a part of phosphorus in slag turns again in molten steel, and so that p element is increased slightly.However, because In converter smelting molten steel, p content is controlled in below 0.010wt%, so while the reducing atmosphere of lf stove can make in molten steel The content of p be increased slightly, but not over 0.020wt%.
Finally, continuous casting and rolling are carried out to the molten steel processing through ladle refining.Big water-coating port encryption envelope in casting process Circle, to prevent n and o in molten steel inspiration air, thus improve the cleanliness factor of molten steel.Furthermore, it is possible to using casing protection cast Mode is poured into a mould to molten steel, and pulling rate scope can control in 0.80m/min~0.90m/min.Cooling system adopts weak cold mould Formula (specific water is less than 0.28l/kg), so can be more beneficial for the adsorption to the field trash in molten steel for the covering slag, also may be used To avoid the secondary oxidation of molten steel.Molten steel after cast formation continuous-cast blank, (for example, can pour into a mould through casting process by molten steel Become the square billet that cross dimensions is 165mm × 200mm), continuous-cast blank can be processed through water under high pressure dephosphorization, to remove continuous-cast blank table The iron scale (phosphorus skin) that face is formed in casting process, then rolls to continuous-cast blank.Continuous-cast blank enters roughing Roughing start rolling temperature can control 1050 DEG C~1150 DEG C, if continuous-cast blank tapping temperature cannot meet the described of continuous-cast blank Roughing start rolling temperature, continuous-cast blank can be carried out heat treated by heating furnace, heat time heating time can be 2h~4h, so that even The temperature of casting strand reaches 1180 DEG C~1200 DEG C.Then rolling process is carried out to the continuous-cast blank meeting breaking down temperature.Rolling Process can be divided into roughing and finish rolling.Roughing can adopt k1~k7 pass, rolls 7 passages altogether, wherein k1, k2 can be using altogether Yoke pass, lengthening coefficient is not less than 8.5.Open water cooling plant after roughing mill, to reduce the roughing finishing temperature of continuous-cast blank, make Roughing finishing temperature can control at 950 DEG C~1050 DEG C.Finish rolling start rolling temperature can control at 900 DEG C~950 DEG C, finishing mill Open water cooling plant afterwards, to reduce the finish rolling finishing temperature of continuous-cast blank it is also possible to prevent the excessive length of the crystal grain of continuous-cast blank Affect intensity and the impact property of material greatly.Finishing temperature can control at 800 DEG C~850 DEG C.Thick by controlled rolling Roll the interior microscopic tissue that can make the rolled piece after rolling with final rolling temperature and form super-refinement ferrite crystal grain, strong by fine grain Change the combination with precipitation strength, intensity, wearability and the impact flexibility of the rolled piece of roll forming can be significantly improved.Rolling finishes Rolled piece on cold bed carry out water-spraying control, after product temperature is down to below 100 DEG C, can by rolled piece feeding straightener carry out Rolled piece is finally cut sizing by aligning.
According to the steel of the present invention, strand can be rolled into H type, but the present invention is not limited to this that is to say, that can root Continuous-cast blank is rolled into the steel of other shapes by size and the operation of rolling according to continuous-cast blank, for example, it is possible to by pouring molten steel Become the square billet that sectional dimension is 165mm × 200mm to be then passed through mill milling and become grooved.
In addition, in order to avoid making subject of the present invention thicken, known technology/operation that here is comprised can be omitted Describe in detail.Therefore, in the manufacture method of the high intensity H type forklift door frame steel of the present invention, the NM operation of here is equal Prior art can be adopted.
With reference to example, the forklift door frame high intensity H type steel of the present invention and its manufacture method are described further, But the present invention is not limited to this.
Example 1
First, just smelt iron water in blast furnace, in the s content of molten iron be 0.010wt% and molten iron temperature is not less than 1280 DEG C When, molten iron is blended into converter and carries out just making steel water.Just steel-making water is carried out in top and bottom combined blown converter, the argon flow amount of argon bottom-blowing For 340nl/min, the oxygen flow of top blast oxygen is 3.8nm3/ min, finishing slag basicity controls below 3.0.Blowing simultaneously to 30kg/t is added in molten steelSteelSulfur content be 0.01wt% steel scrap, be simultaneously introduced VN alloy and nickel plate, control molten steel V content is 0.06wt%, ni content is 0.1wt%.And when the p content of molten steel is 0.010wt%, to ladle tapping.
In ladle tapping process, when molten steel goes out to 1/4, be aligned steel stream impact zone adds silicomangan, high carbon ferromanganese to close Gold, ferrocolumbium and ferro-aluminum manganese alloy come to control the si content of molten steel be 0.20wt%, mn content be 1.5wt%, nb content For 0.025wt%, and alloying element adds when molten steel goes out to 3/4.
Then, lf refining treatment is carried out to the molten steel in ladle.Lf refining process is using whole argon bottom-blowing stirring, refine During argon pressure control argon pressure before 95nl/min, outbound to control in 40nl/min, argon blowing time be 12min. Add Calx to carry out slag making according to practical situation, and the slag before outbound is adjusted to by white slag or yellowish-white slag using Acetylenogen., and And the retention time of yellowish-white slag or white slag is 10min.The o content of molten steel is controlled to be using adding Si-Ca-Ba in molten steel 9ppm, add carbon come to adjust molten steel c content be 0.30wt%.
Afterwards, the molten steel after the process of lf stove is poured into, by continuous casting process, the square billet that sectional dimension is 165 × 200mm. In casting process, big water-coating port is encrypted seal and by the way of casing protection cast, molten steel is poured into a mould, and cooling system adopts Weak cold pattern (specific water is less than 0.28l/kg), pulling rate is 0.80m/min.The chemistry one-tenth of tundish steel sample analysis steel is taken before continuous casting It is divided into: p, 0.1wt% of s, 0.015wt% of mn, 0.010wt% of si, 1.50wt% of c, 0.22wt% of 0.30wt% V, 0.025wt% of ni, 0.06wt% nb, remaining be fe and inevitable impurity.
Molten steel pours into after the continuous casting square billet that sectional dimension is 165mm × 200mm through continuous casting process, to continuous casting square billet table Face carries out water under high pressure dephosphorization process.Then continuous casting square billet feeding heating furnace is carried out heat treated 2h, after heated stove heat The continuous casting square billet that temperature reaches 1200 DEG C carries out roughing and finish rolling.Roughing adopts k1~k7 pass, rolls 7 passages altogether, wherein k1, K2 adopts conjugate pass, and lengthening coefficient is not less than 8.5, and the roughing start rolling temperature that continuous casting square billet enters roughing is 1150 DEG C, roughing Finishing temperature is 1050 DEG C, and finish rolling start rolling temperature is 950 DEG C, and finish rolling finishing temperature is 850 DEG C.Roll cold bed on the rolled piece finishing Carry out water-spraying control, after rolled piece temperature is down to 90 DEG C, rolled piece feeding straightener is aligned, finally rolled piece is cut scale Very little, obtain H type steel.
Example 2
First, just smelt iron water in blast furnace, in the s content of molten iron be 0.008wt% and molten iron temperature is not less than 1280 DEG C When, molten iron is blended into converter and carries out just making steel water.Just steel-making water is carried out in top and bottom combined blown converter, the argon flow amount of argon bottom-blowing For 390nl/min, the oxygen flow of top blast oxygen is 3nm3/ min, finishing slag basicity controls below 3.0.In blowing simultaneously to steel 20kg/t is added in waterSteelSulfur content be 0.008wt% steel scrap, be simultaneously introduced VN alloy and nickel plate, control the v of molten steel Content is 0.1wt%, ni content is 0.16wt%.And when the p content of molten steel is 0.008wt%, to ladle tapping.
In ladle tapping process, when molten steel goes out to 1/4 be aligned steel stream impact zone add silicomangan, high carbon ferromanganese, Ferrocolumbium and aluminum-manganese-iron alloy controlling the si content of molten steel for 0.40wt%, mn content for 1.30wt%, nb content are 0.005wt%, o content is 46ppm, and alloying element adds when molten steel goes out to 3/4.
Then, lf refining treatment is carried out to the molten steel in ladle.Lf refining process is using whole argon bottom-blowing stirring, refine During argon pressure control argon pressure before 120nl/min, outbound to control in 50nl/min, argon blowing time be 11min. Add Calx to carry out slag making according to practical situation, and the slag before outbound is adjusted to by white slag or yellowish-white slag using carborundum, and And the retention time of yellowish-white slag or white slag is 10min.To control the o content in steel to be 10ppm, add carbon using silicomanganese and ferrosilicon It is 0.24wt% to adjust the c content in molten steel.
Afterwards, the molten steel after the process of lf stove is poured into, by continuous casting process, the square billet that sectional dimension is 165 × 200mm. In casting process, big water-coating port is encrypted seal and by the way of casing protection cast, molten steel is poured into a mould, and cooling system adopts Weak cold pattern (specific water is less than 0.28l/kg), pulling rate is 0.90m/min.The chemistry one-tenth of tundish steel sample analysis steel is taken before continuous casting It is divided into: p, 0.16wt% of s, 0.013wt% of mn, 0.008wt% of si, 1.30wt% of c, 0.40wt% of 0.24wt% V, 0.005wt% of ni, 0.10wt% nb, remaining be fe and inevitable impurity.
Molten steel pours into after the continuous casting square billet that sectional dimension is 165mm × 200mm through continuous casting process, to continuous casting square billet table Face carries out water under high pressure dephosphorization process.Then continuous casting square billet feeding heating furnace is carried out heat treated 3h, after heated stove heat The continuous casting square billet that temperature reaches 1180 DEG C carries out roughing and finish rolling.Roughing adopts k1~k7 pass, rolls 7 passages altogether, wherein k1, K2 adopts conjugate pass, and lengthening coefficient is not less than 8.5, and the roughing start rolling temperature that continuous casting square billet enters roughing is 1100 DEG C, roughing Finishing temperature is 1000 DEG C, and finish rolling start rolling temperature is 900 DEG C, and finish rolling finishing temperature is 800 DEG C.Roll cold bed on the rolled piece finishing Carry out water-spraying control, after rolled piece temperature is down to 100 DEG C, rolled piece feeding straightener is aligned, it is fixed finally to cut rolled piece Size, obtains H type steel.
Example 3
First, just smelt iron water in blast furnace, in the s content of molten iron be 0.009wt% and molten iron temperature is not less than 1280 DEG C When, molten iron is blended into converter and carries out just making steel water.Just steel-making water is carried out in top and bottom combined blown converter, the argon flow amount of argon bottom-blowing For 310nl/min, the oxygen flow of top blast oxygen is 4.5nm3/ min, finishing slag basicity controls below 3.0.Blowing simultaneously to 40kg/t is added in molten steelSteelSulfur content be 0.08wt% steel scrap, be simultaneously introduced VN alloy and nickel plate, control molten steel V content is 0.08wt%, ni content is 0.2wt%.And molten steel p content be 0.008wt%, to ladle tapping.
In ladle tapping process, when molten steel goes out to 1/4 be aligned steel stream impact zone add silicomangan, high carbon ferromanganese, Ferrocolumbium and aluminum-manganese-iron alloy controlling the si content of molten steel for 0.30wt%, mn content for 1.40wt%, nb content are 0.040wt%, o content is 49ppm, and alloying element adds when molten steel goes out to 3/4.
Then, lf refining treatment is carried out to the molten steel in ladle.Lf refining process is using whole argon bottom-blowing stirring, refine During argon pressure control argon pressure before 150nl/min, outbound to control in 80nl/min, argon blowing time be 11min. Add Calx to carry out slag making according to practical situation, and the slag before outbound is adjusted to by white slag or yellowish-white slag using Acetylenogen., and And the retention time of yellowish-white slag or white slag is 10min.To control using ferrosilicon the o content in steel to be 9ppm, to add carbon to adjust C content in molten steel is 0.27wt%.
Afterwards, the molten steel after the process of lf stove is poured into, by continuous casting process, the side that sectional dimension is 165mm × 200mm Base.In casting process, big water-coating port is encrypted seal and by the way of casing protection cast, molten steel is poured into a mould, cooling system Using weak cold pattern (specific water is less than 0.28l/kg), pulling rate is 0.80m/min.The change of tundish steel sample analysis steel is taken before continuous casting Study and be divided into: the p of s, 0.015wt% of mn, 0.009wt% of si, 1.40wt% of c, 0.30wt% of 0.27wt%, The nb of v, 0.040wt% of ni, 0.08wt% of 0.2wt%, remaining is fe and inevitable impurity.
Molten steel pours into after the continuous casting square billet that sectional dimension is 165mm × 200mm through continuous casting process, to continuous casting square billet table Face carries out water under high pressure dephosphorization process.Then continuous casting square billet feeding heating furnace is carried out heat treated 3h, after heated stove heat The continuous casting square billet that temperature reaches 1190 DEG C carries out roughing and finish rolling.Roughing adopts k1~k7 pass, rolls 7 passages altogether, wherein k1, K2 adopts conjugate pass, and lengthening coefficient is not less than 8.5, and the roughing start rolling temperature that continuous casting square billet enters roughing is 1080 DEG C, roughing Finishing temperature is 980 DEG C, and finish rolling start rolling temperature is 920 DEG C, and finish rolling finishing temperature is 830 DEG C.Roll cold bed on the rolled piece finishing Carry out water-spraying control, after rolled piece temperature is down to 100 DEG C, rolled piece feeding straightener is aligned, it is fixed finally to cut rolled piece Size, obtains H type steel.
Above example 1 is listed in Table 1 below to the performance of the H type steel of example 3, and wherein performance test methods adopt international side Method.
Table 1: in example 1~3, H type door frame Steel Properties measure
From table 1, excellent intensity, hardness and impact flexibility are had according to the H type steel that example 1 to example 3 manufactures, Therefore can be used to make forklift door frame.
In sum, the production compared with the forklift door frame H type steel of technology compares, the spy of technical scheme Point is as follows.
First, in steel-making water at the beginning of converter, using aluminum-manganese-iron alloy deoxidation, and in molten steel tapping process, using silico-calcium In barium, silicomanganese and ferrosilicon at least one come final deoxidizing so that the forklift door frame H type oxygen content in steel of the present invention is less than 10ppm, produces the clean steel of low oxygen content.
Second, produce and encrypt seal using big water-coating port during square billet and carry out molten steel by the way of casing protection cast Cast, improve the cleanliness factor of molten steel, realize permanent pulling rate, improve the quality of strand, produce high-strength mechanical manufacture and use Steel.
3rd, add micro v, ni, nb alloy, with refined crystalline strengthening and the precipitation strength mechanism of alloying element, do not increasing Plus on the premise of production cost, improve intensity and the impact flexibility of forklift door frame H type steel.
4th, the forklift door frame of the present invention yield strength function admirable of H type steel, average out to 568mpa.
It will be understood by those skilled in the art that above example is merely illustrative, and infinite.Although with reference to above-mentioned Embodiment has been described in detail to the present invention, it will be understood by those within the art that, still the present invention can be entered Row modification or equivalent, any modification or partial replacement without departing from the spirit and scope of the present invention, it all should be covered In the middle of scope of the presently claimed invention.

Claims (6)

1. a kind of forklift door frame manufacture method of high intensity H type steel, described manufacture method comprises the following steps:
A () just smelts iron water;
(b) when the s content of molten iron is less than 0.01wt%, using making steel water at the beginning of converter;
C v content that () adjusts molten steel is 0.05wt%~0.1wt%, ni content is 0.1wt%~0.2wt%, and in molten steel P content when being less than 0.010wt%, to ladle tapping;
D (), during tapping to ladle, the si content of adjustment molten steel is 0.20wt%~0.38wt%, mn content is 1.2wt%~1.5wt%, nb content are 0.025wt%~0.05wt%, o content is less than 50ppm;
(e) adjust in ladle refining furnace c content in molten steel be 0.24wt%~0.30wt%, o content be less than 10ppm;
F () carries out continuous casting to molten steel, to obtain continuous-cast blank;
G () carries out roughing, finish rolling and aligning to continuous-cast blank, thus obtaining forklift door frame high intensity H type steel;
Wherein, in step (e), the stirring of whole argon bottom-blowing, the argon pressure in refining process control 90nl/min~ 150nl/min, before outbound, argon pressure controls in 30nl/min~80nl/min, and argon blowing time is no less than 11min, using carbonization Slag before outbound is adjusted to white slag or yellowish-white slag, using Si-Ca-Ba, silicomanganese or ferrosilicon by least one in calcium or carborundum In the o of at least one control outbound molten steel content be less than 10ppm,
Wherein, in step (g), roughing start rolling temperature controls at 1050 DEG C~1150 DEG C, and roughing finishing temperature control is at 950 DEG C ~1050 DEG C, finish rolling start rolling temperature controls at 900 DEG C~950 DEG C, and finish rolling finishing temperature controls at 800 DEG C~850 DEG C,
Wherein, the chemical composition of described forklift door frame high intensity H type steel is: c, 0.20wt% of 0.24wt%~0.30wt% The mn of si, 1.2wt% of~0.40wt%~1.5wt%, less than 0.020wt% p, less than 0.010wt% s, The nb of ni, 0.025wt% of v, 0.1wt% of 0.05wt%~0.1wt%~0.2wt%~0.05wt%, balance of ferrum and Inevitably impurity.
2. manufacture method as claimed in claim 1, wherein, in step (b), makes steel water using at the beginning of top and bottom combined blown converter, and Sulfur content is added to be less than the steel scrap of 0.01wt% in molten steel.
3. manufacture method as claimed in claim 1, wherein, in step (c), to be controlled using adding nitrogen-vanadium alloy in molten steel V content in molten steel processed, to control the ni content in molten steel using adding nickel plate in molten steel.
4. manufacture method as claimed in claim 1, wherein, in step (d), when molten steel goes out to 1/4, is directed at steel stream impact zone It is uniformly added into the content to control the alloying element of molten steel for the alloy adjusting molten steel composition, until adding when molten steel goes out to 3/4, its In, using adding silicomangan to control the si content of molten steel in molten steel, add high carbon ferromanganese alloy to control the mn of molten steel Content, adds ferrocolumbium to control the nb content of molten steel, adds aluminum-manganese-iron alloy to control the o content of molten steel.
5. manufacture method as claimed in claim 1, wherein, step (e) also includes, the composition to molten steel in lf purifier It is finely adjusted.
6. manufacture method as claimed in claim 1, wherein, in step (f), continuous casting adopts molding casting, pulling rate scope control System is in 0.80m/min~0.90m/min.
CN201410213192.4A 2014-05-20 2014-05-20 High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof Active CN103966503B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410213192.4A CN103966503B (en) 2014-05-20 2014-05-20 High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410213192.4A CN103966503B (en) 2014-05-20 2014-05-20 High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof

Publications (2)

Publication Number Publication Date
CN103966503A CN103966503A (en) 2014-08-06
CN103966503B true CN103966503B (en) 2017-01-25

Family

ID=51236500

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410213192.4A Active CN103966503B (en) 2014-05-20 2014-05-20 High-strength H-shaped steel for mast of forklift truck and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN103966503B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104711476A (en) * 2015-03-12 2015-06-17 山东钢铁股份有限公司 Channel steel for hot rolling of forklift portal and preparation method of channel steel
CN107964625A (en) * 2017-11-09 2018-04-27 石家庄钢铁有限责任公司 A kind of big specification pallet fork round steel of low-temperature impact-resistant toughness and its production method

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3505389B2 (en) * 1997-10-20 2004-03-08 新日本製鐵株式会社 Steel for strip, Si-killed steel, and production method by continuous casting
CN101225499B (en) * 2008-01-31 2010-04-21 上海交通大学 Low-alloy super-strength multiphase steel and heat treatment method thereof
CN102618782B (en) * 2012-03-30 2013-12-25 莱芜钢铁集团有限公司 Large-specification Z-direction H-steel and preparation method thereof
CN102618781B (en) * 2012-03-30 2013-11-06 莱芜钢铁集团有限公司 Hot-rolled H-steel for low temperature-resistance structure and preparation method for hot-rolled H-steel
CN103540844B (en) * 2013-10-28 2016-04-06 莱芜钢铁集团有限公司 Low temperature resistant H profile steel and production method thereof

Also Published As

Publication number Publication date
CN103966503A (en) 2014-08-06

Similar Documents

Publication Publication Date Title
CN102618792B (en) High-strength abrasion-resistant steel for engineering machinery and manufacturing method thereof
CN103540845B (en) Yield strength is latten Glassed Steel and the manufacture method of 330MPa level
CN103160729B (en) Medium-carbon microalloyed steel for engineering machinery caterpillar chain piece and production process thereof
CN104630641B (en) 800MPa-grade high-strength high-plasticity low-carbon medium-manganese steel and manufacturing method thereof
JP5687624B2 (en) Stainless steel, cold-rolled strip made from this steel, and method for producing steel plate products from this steel
CN101008066B (en) Hot rolling martensite steel plate with tensile strength higher than 1000Mpa and its production method
CN106521324B (en) A kind of wind-powered electricity generation countershaft-gear carburizing steel and preparation method thereof
CN102618782B (en) Large-specification Z-direction H-steel and preparation method thereof
CN104532102B (en) Manufacturing technology of large-sized carburized bearing steel G20Cr2Ni4A for wind electricity
US20160017449A1 (en) 700MPA-Level High-Strength Hot Rolling Q&P Steel And Method Of Manufacturing The Same
CN106350734B (en) High-strength tenacity non-hardened and tempered steel wire rod and preparation method thereof
CN107177770B (en) The production method of cold rolling low alloy high strength steel plate
CN103266287B (en) Carbon ferritic in one-pearlite type non-hardened and tempered steel and manufacture method thereof
CN102586688B (en) A kind of dual phase sheet steel and manufacture method thereof
US5972129A (en) Process for smelting a titanium steel and steel obtained
CN101724778B (en) Steel for automobile beam and with yield strength more than 500 MPa and manufacturing method thereof
CN102002628B (en) Method for manufacturing low-carbon steel sheets
CN109097705A (en) A kind of 800MPa grade cold rolling hot dip galvanizing dual phase steel and its production method
CN101255530B (en) High-strength steel for water heater inner container and production method thereof
CN107641759A (en) Method based on CSP flows production Thin Specs hot forming steel
CN109234627B (en) High-strength high-toughness non-quenched and tempered round steel and preparation method thereof
CN106167875B (en) A kind of strength and ductility product is more than 20GPa% economical high strength cold-rolled TRIP steel and preparation method thereof
CN110257719A (en) A kind of micro-alloyed with Nb and Ti HRB400 grades of screw-thread steels and its manufacturing method
CN104911497B (en) A kind of high intensity carbonized Gear Steel 19CrNi5 production method
CN105925887A (en) 980 MPa-grade hot-rolled ferritic bainite dual-phase steel and manufacturing method thereof

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model