CN103643116B - The manufacturing process of a kind of welded gas cylinder and hot-rolled steel sheet thereof - Google Patents
The manufacturing process of a kind of welded gas cylinder and hot-rolled steel sheet thereof Download PDFInfo
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Abstract
The invention discloses the manufacturing process of hot-rolled steel plates for welded gas cylinder, comprise carry out successively steel-making, continuous casting, add hot continuously cast material, hot rolling, batch, in steel-making step, control S content≤0.015% in molten steel, Si content≤0.10% carry out Ca process, by weight percentage, the chemical composition of gained molten steel is the Fe of C:0.13 ~ 0.18%, Si≤0.10%, Mn:0.70 ~ 1.10%, P≤0.020%, S≤0.015%, Als:0.015 ~ 0.10%, Ti:0.01 ~ 0.02% and surplus and inevitable impurity; Adding in hot continuously cast material step, controlling preheating section temperature≤1000 DEG C, heating zone temperature is being 1320 ~ 1340 DEG C, soaking zone temperature is being 1300 ~ 1320 DEG C, tapping temperature is being 1200 ~ 1250 DEG C; In the step of hot rolling, controlling entry temperature at finishing is 950 ~ 1050 DEG C, and exit temperature at finishing is 840 ~ 890 DEG C; Batching in step, when the carbon content of steel is 0.13 ~ 0.15%, controlling coiling temperature is 610 ~ 630 DEG C; When the carbon content of steel is 0.16 ~ 0.18%, controlling coiling temperature is 640 ~ 660 DEG C.
Description
Technical field
The present invention relates to engineering materials technical field, more particularly, relate to the manufacturing process of the high welded gas cylinder of a kind of Volume variation rate and hot-rolled steel sheet thereof.
Background technology
Along with the development of China Petroleum and the raising day by day of living standards of the people, household bottled liquefied petroleum gas extensively enters town and country huge numbers of families, and wherein, more than 80% of YSP-l5 type liquefied petroleum gas steel cylinder is the welded gas cylinder made by HP295 hot-rolled steel sheet.Welded gas cylinder belongs to two type III pressure vessel, the fine or not direct relation of its performance the safety of user, therefore, national standard has carried out strict regulation to the properties of welded gas cylinder, the welded gas cylinder made of HP295 hot-rolled steel sheet is except must meeting required every mechanical property, and welded gas cylinder also needs to carry out that strict sampling observation hydraulic bursting test is qualified just can put on market afterwards.When welded gas cylinder carries out the water test, the ratio of the water capacity of gas cylinder before the volume increase of gas cylinder and test when Volume variation rate when it breaks refers to explosion.
This is because, the welded gas cylinder filling liquefied petroleum gas (LPG) is generally used in the hot environment such as restaurant and kitchen, when welded gas cylinder in use runs into high temperature, pressure of the inside of a bottle can raise, if the volume of gas cylinder is less than standard value, its distortion allowance is little, accident of easily blasting, therefore require that welded gas cylinder must carry out hydraulic bursting test and Volume variation rate need be greater than 10%, to guarantee that welded gas cylinder has enough safety reservations.
At present, the document studied welding gas cylinder volume deformation rate is less, suitable length-to-diameter ratio scope mainly namely how is chosen from structural shape aspect to improve the Volume variation rate of steel cylinder in prior art, or research thermal treatment and material hardness are on the impact of cylinder for liquefied gas Volume variation rate, do not relate to the technology improving welded gas cylinder Volume variation rate by improving the manufacturing process of hot-rolled steel sheet.
Summary of the invention
For the deficiencies in the prior art, an object of the present invention is to solve in above-mentioned prior art the one or more problems existed.
A kind of performance by improving hot-rolled steel sheet is the object of the present invention is to provide to improve the method for welded gas cylinder Volume variation rate and provide a kind of welded gas cylinder with high volume deformation rate
To achieve these goals, one aspect of the present invention provides a kind of manufacturing process of hot-rolled steel plates for welded gas cylinder, described manufacturing process comprises the steel-making carried out successively, continuous casting, add hot continuously cast material, hot rolling, batch, wherein, in the step of steel-making, control S content≤0.015% in molten steel, Si content≤0.10% also carries out Ca process, wherein, by weight percentage, the chemical composition of gained molten steel is C:0.13 ~ 0.18%, Si≤0.10%, Mn:0.70 ~ 1.10%, P≤0.020%, S≤0.015%, Als:0.015 ~ 0.10%, the Fe of Ti:0.01 ~ 0.02% and surplus and inevitable impurity, in the step adding hot continuously cast material, control preheating section temperature≤1000 DEG C, heating zone temperature is 1320 ~ 1340 DEG C, soaking zone temperature is 1300 ~ 1320 DEG C, tapping temperature is 1200 ~ 1250 DEG C, in the step of hot rolling, controlling entry temperature at finishing is 950 ~ 1050 DEG C, and exit temperature at finishing is 840 ~ 890 DEG C, in the step of batching, when the carbon content of steel is 0.13 ~ 0.15%, controlling coiling temperature is 610 ~ 630 DEG C, when the carbon content of steel is 0.16 ~ 0.18%, controlling coiling temperature is 640 ~ 660 DEG C.
According to an embodiment of the manufacturing process of hot-rolled steel plates for welded gas cylinder of the present invention, in the step of steel-making, carry out Ca process by feeding Ca-Fe cored-wire.
According to an embodiment of the manufacturing process of hot-rolled steel plates for welded gas cylinder of the present invention, the thickness of described hot-rolled steel sheet is 3 ~ 3.5mm.
According to an embodiment of the manufacturing process of hot-rolled steel plates for welded gas cylinder of the present invention, unit elongation >=30% of described hot-rolled steel sheet, relative reduction in area >=60%.
Present invention also offers a kind of welded gas cylinder, described welded gas cylinder is processed by the hot-rolled steel sheet of the manufacturing process manufacture of the hot-rolled steel plates for welded gas cylinder described in above-mentioned any one.
According to an embodiment of welded gas cylinder of the present invention, the Volume variation rate of described welded gas cylinder is greater than 15%.
The present invention, by controlling converter steelmaking process, makes the Sulfide inclusion of hot-rolled steel sheet and silicate inclusion be spherical or short strip shape distribution; Simultaneously by controlling Heating temperature, entry temperature at finishing and exit temperature at finishing during hot rolling, and the coiling temperature under different carbon content, make the hot-rolled steel sheet of 3.0 ~ 3.5mm thickness have higher unit elongation and relative reduction in area.Further, the welded gas cylinder that the hot-rolled steel sheet produced by method of the present invention makes has higher Volume variation rate, improves welded gas cylinder security in actual use.
Embodiment
Hereinafter, the manufacturing process of hot-rolled steel plates for welded gas cylinder of the present invention will be described in detail in conjunction with exemplary embodiment.In the present invention, the statement made an exception if do not have, then involved per-cent is mass percent.
In prior art; when sampling observation hydraulic bursting test is carried out to the welded gas cylinder of hot-rolled steel sheet making; often there will be the situation of the Volume variation rate < 10% of welded gas cylinder; if the Volume variation rate of welded gas cylinder does not reach the standard-required being greater than 10%; then this batch of gas cylinder is judged to defective; can not use be put on market, therefore cause material, artificial etc. waste.Because breaking when welded gas cylinder carries out hydraulic bursting test is generally ductile fracture, and one of principal character of ductile fracture is that before breaking, materials and structures will produce larger viscous deformation, the present invention is just based on this point discovery, there is provided a kind of by improving the converter smelting of hot-rolled steel sheet and the method for hot rolling production technique, carry out reaching and improve the unit elongation of hot-rolled steel sheet and the object of relative reduction in area, and ensure that gas cylinder has enough plasticity storages further, thus ensure that the Volume variation rate of the welded gas cylinder that hot-rolled steel sheet makes reaches more than 15%.
According to an exemplary embodiment of the present invention the manufacturing process of hot-rolled steel plates for welded gas cylinder comprise carry out successively steel-making, continuous casting, add hot continuously cast material, hot rolling, the step of batching.The present invention mainly in steel-making, add hot continuously cast material, hot rolling, the step such as to batch in improve, specific as follows:
First, in the step of converter steelmaking, control the S content in molten steel, and S content is controlled below 0.015%, be mingled with to reduce steel medium sulphide content.Control Si content in molten steel below 0.10%, to reduce strip Silicate Inclusions in steel simultaneously.And in the process of LF stove steel-making, Ca process is carried out to molten steel, to make the strip sulfide inclusion in steel become inclusion that is spherical or short strip shape, preferably, carry out Ca process by feeding Ca-Fe cored-wire.And, by weight percentage, the chemical composition of smelting gained molten steel is the Fe of C:0.13 ~ 0.18%, Si≤0.10%, Mn:0.70 ~ 1.10%, P≤0.020%, S≤0.015%, Als:0.015 ~ 0.10%, Ti:0.01 ~ 0.02% and surplus and inevitable impurity.
The unit elongation of steel plate and relative reduction in area are affected comparatively large because steel medium sulphide content is mingled with the form of Silicate Inclusions and size, and then affect the viscous deformation of hot-rolled steel sheet and welded gas cylinder.If the S content in steel and Si content higher, the strip sulfide inclusion of the more integrated distribution then existed in steel and Silicate Inclusions will be split steel matrix and destroy the continuity of steel matrix, to plasticity and the toughness of steel plate be had a strong impact on, and then reduce unit elongation and the relative reduction in area of steel plate.Then when the welded gas cylinder generation viscous deformation that hot-rolled steel sheet makes, microvoid will be sprouted around strip inclusion, along with the increase of gas cylinder deflection, microvoid will be expanded gradually, if the strip sulfide inclusion in steel plate and strip Silicate Inclusions more, microvoid will couple together and make to be mingled with the distribution in strip, finally cause gas cylinder to ftracture.Therefore, according to the present invention, the Si content in steel will be controlled on the one hand, reduce the quantity that steel mesosilicic acid salt is mingled with, the S content in steel will be controlled on the other hand simultaneously, reduce the quantity that steel medium sulphide content is mingled with, and Calcium treatment will be carried out when making steel to molten steel, make the strip sulfide in steel become spherical inclusion.Preferably, adopt Ca-Fe cored-wire to carry out Calcium treatment, and avoid adopting Ca-Si cored-wire to carry out Calcium treatment to molten steel, in order to avoid improve the Si content in steel, cause the consequence that steel mesosilicic acid salt increases.
Afterwards, in the step adding hot continuously cast material, control preheating section temperature≤1000 DEG C, heating zone temperature is 1320 ~ 1340 DEG C, soaking zone temperature is 1300 ~ 1320 DEG C, tapping temperature is 1200 ~ 1250 DEG C.In the step of hot rolling, controlling entry temperature at finishing is 950 ~ 1050 DEG C, and exit temperature at finishing is 840 ~ 890 DEG C.In the step of batching, when the carbon content of steel is 0.13 ~ 0.15%, controlling coiling temperature is 610 ~ 630 DEG C; When the carbon content of steel is 0.16 ~ 0.18%, controlling coiling temperature is 640 ~ 660 DEG C.
Because hot rolling Heating temperature, finish rolling entrance and exit temperature, coiling temperature have larger impact to the unit elongation of steel plate and relative reduction in area, therefore the present invention when hot rolling by controlling preheating section temperature≤1000 DEG C, heating zone temperature 1320 ~ 1340 DEG C, soaking zone temperature 1300 ~ 1320 DEG C, to ensure that tapping temperature is 1200 ~ 1250 DEG C.If tapping temperature > 1250 DEG C, easily cause steel plate coarse microstructure, reduce unit elongation and the relative reduction in area of steel plate, if tapping temperature < 1200 DEG C, easily cause steel plate to heat uneven, finally cause plate property uneven.
By control entry temperature at finishing be 950 ~ 1050 DEG C, exit temperature at finishing is 840 ~ 890 DEG C, ensureing that hot-rolled steel sheet has on the basis of the intensity index of regulation, also making it have good plasticity index, namely having higher unit elongation and relative reduction in area.
Further, when batching steel plate, suitably should control coiling temperature according to the carbon content of steel, if do not consider the carbon content of steel and take single coiling temperature scope, then the mechanical property of steel plate can be caused not mate.Specifically, if be 610 ~ 630 DEG C by oiler temperature control, then, when the carbon content of steel is 0.13 ~ 0.15%, while ensureing that steel plate has the intensity of standard-required, steel plate has higher unit elongation and relative reduction in area; But when the carbon content of steel is 0.16 ~ 0.18%, if coiling temperature still controls to be 610 ~ 630 DEG C, then the amplitude of the intensity raising of steel plate is comparatively large, but unit elongation and relative reduction in area will significantly reduce simultaneously.If when being 640 ~ 660 DEG C by oiler temperature control, when the carbon content of steel is 0.16 ~ 0.18%, then, while ensureing that steel plate has the intensity of standard-required, steel plate has higher unit elongation and relative reduction in area; But when the carbon content of steel is 0.13 ~ 0.15%, if coiling temperature still controls to be 640 ~ 660 DEG C, although steel plate can have higher unit elongation and relative reduction in area, the intensity of steel plate can not reach the standard-required of gas cylinder steel plate.Therefore, the coiler plate temperature different according to different steel carbon content controls is needed, to obtain the optimum matching of hot-rolled steel sheet mechanical property.
Produced the hot-rolled steel plates for welded gas cylinder of 3.0 ~ 3.5mm thickness by above method, there is higher unit elongation and relative reduction in area.According to one embodiment of present invention, unit elongation >=30% of prepared hot-rolled steel plates for welded gas cylinder, relative reduction in area >=60%.
Welded gas cylinder of the present invention is then processed by the hot-rolled steel sheet of the manufacturing process manufacture of above-mentioned hot-rolled steel plates for welded gas cylinder, and its Volume variation rate is greater than 15%.
The present invention is described in detail below by concrete example.
Example 1 to 9 all utilizes the manufacturing process of above hot-rolled steel plates for welded gas cylinder to manufacture hot-rolled steel sheet, wherein, S content≤0.015% in molten steel is controlled during converter steelmaking, at the Ca-Fe cored-wire of LF stove to every stove steel feeding 800m, control Si content≤0.10% in molten steel simultaneously, the molten steel composition smelting gained in each example is as shown in table 1, heating in each example, hot rolling, the temperature control parameter of technique and the unit elongation of each example gained hot-rolled steel sheet such as to batch, the Volume variation rate result of end face shrinking percentage and the welded gas cylinder that adopts this hot-rolled steel sheet to make is as shown in table 2.
Molten steel composition/the % of table 1 example 1 to 9
| Sequence number | C | Si | Mn | P | S | Als | Ti |
| 1 | 0.13 | 0.08 | 0.95 | 0.018 | 0.014 | 0.020 | 0.02 |
| 2 | 0.15 | 0.07 | 0.85 | 0.015 | 0.010 | 0.026 | 0.01 |
| 3 | 0.18 | 0.06 | 0.75 | 0.013 | 0.010 | 0.025 | 0.02 |
| 4 | 0.14 | 0.05 | 0.90 | 0.010 | 0.008 | 0.030 | 0.02 |
| 5 | 0.16 | 0.07 | 1.00 | 0.009 | 0.007 | 0.030 | 0.01 |
| 6 | 0.18 | 0.05 | 0.95 | 0.012 | 0.006 | 0.040 | 0.01 |
| 7 | 0.13 | 0.06 | 1.10 | 0.009 | 0.005 | 0.035 | 0.02 |
| 8 | 0.14 | 0.08 | 0.97 | 0.010 | 0.008 | 0.028 | 0.02 |
| 9 | 0.16 | 0.05 | 1.10 | 0.014 | 0.009 | 0.040 | 0.01 |
Controling parameters in table 2 example 1 to 9 and product performance
As shown in table 2, adopt that the unit elongation of the hot-rolled steel sheet of the manufacturing process gained of hot-rolled steel plates for welded gas cylinder of the present invention is 32 ~ 40%, relative reduction in area is 64 ~ 71%.The Volume variation rate adopting the welded gas cylinder of this hot-rolled steel sheet manufacture is 18 ~ 30%, far above national standard.
Therefore, adopt the hot-rolled steel sheet of the fabrication process of hot-rolled steel plates for welded gas cylinder of the present invention, while its tensile strength of guarantee and yield strength, make it have higher plasticity, namely there is higher unit elongation and relative reduction in area; And the welded gas cylinder adopting this hot-rolled steel sheet to make has higher Volume variation rate, improve the lumber recovery of hot-rolled steel sheet on the one hand, improve the security of welded gas cylinder on the other hand.
Although specifically describe the present invention, those skilled in the art will appreciate that without departing from the spirit and scope of the present invention, various forms of change can be made to the present invention.
Claims (6)
1. a manufacturing process for hot-rolled steel plates for welded gas cylinder, is characterized in that, described manufacturing process comprise carry out successively steel-making, continuous casting, add hot continuously cast material, hot rolling, batch, wherein,
In the step of steel-making, control S content≤0.015% in molten steel, Si content≤0.10% carry out Ca process, wherein, by weight percentage, the chemical composition of gained molten steel is the Fe of C:0.13 ~ 0.18%, Si≤0.10%, Mn:0.70 ~ 1.10%, P≤0.020%, S≤0.015%, Als:0.015 ~ 0.10%, Ti:0.01 ~ 0.02% and surplus and inevitable impurity;
In the step adding hot continuously cast material, control preheating section temperature≤1000 DEG C, heating zone temperature is 1320 ~ 1340 DEG C, soaking zone temperature is 1300 ~ 1320 DEG C, tapping temperature is 1200 ~ 1250 DEG C;
In the step of hot rolling, controlling entry temperature at finishing is 950 ~ 1050 DEG C, and exit temperature at finishing is 840 ~ 890 DEG C;
In the step of batching, when the carbon content of steel is 0.13 ~ 0.15%, controlling coiling temperature is 610 ~ 630 DEG C; When the carbon content of steel is 0.16 ~ 0.18%, controlling coiling temperature is 640 ~ 660 DEG C.
2. the manufacturing process of hot-rolled steel plates for welded gas cylinder according to claim 1, is characterized in that, in the step of steel-making, carries out Ca process by feeding Ca-Fe cored-wire.
3. the manufacturing process of hot-rolled steel plates for welded gas cylinder according to claim 1, is characterized in that, the thickness of described hot-rolled steel sheet is 3 ~ 3.5mm.
4. the manufacturing process of hot-rolled steel plates for welded gas cylinder according to claim 1, is characterized in that, unit elongation >=30% of described hot-rolled steel sheet, relative reduction in area >=60%.
5. a welded gas cylinder, is characterized in that, the hot-rolled steel sheet of the manufacturing process manufacture of the hot-rolled steel plates for welded gas cylinder of described welded gas cylinder according to any one of Claims 1-4 processes.
6. welded gas cylinder according to claim 5, is characterized in that, the Volume variation rate of described welded gas cylinder is greater than 15%.
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| CN109518093A (en) * | 2018-12-17 | 2019-03-26 | 包头钢铁（集团）有限责任公司 | A kind of civilian gas cylinder hot rolled strip and preparation method thereof |
| CN109855982A (en) * | 2019-01-21 | 2019-06-07 | 中国石油天然气集团有限公司 | A kind of liquefied petroleum gas cylinder explosion test device and test method |
| CN110732552A (en) * | 2019-10-23 | 2020-01-31 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for heating high-strength hot-rolled steel sheet |
| CN114196889B (en) * | 2021-11-29 | 2022-11-08 | 湖南华菱涟源钢铁有限公司 | Hot-rolled steel sheet material, method for producing same and product |
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| CN102191438A (en) * | 2010-03-18 | 2011-09-21 | 宝山钢铁股份有限公司 | Steel plate for seamless high pressure gas cylinder, and manufacture method thereof |
| CN102071355A (en) * | 2011-01-27 | 2011-05-25 | 河北钢铁股份有限公司唐山分公司 | Steel for liquefied petroleum gas cylinders produced by continuous casting and rolling of medium and thin slabs and production method thereof |
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