CN104307897A - Process method for removing pit defects from surface of steel strip - Google Patents
Process method for removing pit defects from surface of steel strip Download PDFInfo
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- CN104307897A CN104307897A CN201410542359.1A CN201410542359A CN104307897A CN 104307897 A CN104307897 A CN 104307897A CN 201410542359 A CN201410542359 A CN 201410542359A CN 104307897 A CN104307897 A CN 104307897A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 98
- 239000010959 steel Substances 0.000 title claims abstract description 98
- 238000000034 method Methods 0.000 title claims abstract description 69
- 230000007547 defect Effects 0.000 title claims abstract description 32
- 239000000498 cooling water Substances 0.000 claims abstract description 81
- 238000005096 rolling process Methods 0.000 claims abstract description 65
- 238000010079 rubber tapping Methods 0.000 claims abstract description 17
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 66
- 229910052742 iron Inorganic materials 0.000 claims description 33
- 238000001816 cooling Methods 0.000 claims description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 6
- 238000005070 sampling Methods 0.000 description 6
- 238000012876 topography Methods 0.000 description 6
- 230000008030 elimination Effects 0.000 description 5
- 238000003379 elimination reaction Methods 0.000 description 5
- 238000005098 hot rolling Methods 0.000 description 3
- 238000005498 polishing Methods 0.000 description 2
- 238000005266 casting Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
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Abstract
The invention discloses a process method for removing pit defects from a surface of a steel strip. The method comprises the following steps of controlling the slab tapping temperature of the steep strip within the range of 1130-1180 DEG C; controlling a rough mill to adopt a three and five-pass rolling mode to roughly roll a slab, and performing full-pass descaling on the slab by the rough rolling procedure; performing finish rolling on the roughly rolled intermediate slab, and controlling the finish rolling inlet temperature of the intermediate slab within the range of 940-980 DEG C; controlling the opening amount of cooling water in a first machine frame between a first finish mill and a second finish mill within the range of 25%-30%; controlling the opening amount of cooling water in a second machine frame between the second finish mill and a third finish mill within the range of 18%-20%; controlling the opening amount of cooling water in a third machine frame between the third finish mill and a fourth finish mill within the range of 18%-20%; controlling the opening amount of cooling water in a fourth machine frame between the fourth finish mill and a fifth finish mill within the range of 45%-50%; controlling the rolling speed of a seventh finish mill within the range of 4.5%-5.5m/s. The process method has the advantage that by optimizing the process of rolling production lines, the occurrence of the pit defects at the surface of the steel strip is avoided at the source.
Description
Technical field
The present invention relates to technical field of steel rolling, particularly relate to a kind of process eliminating belt steel surface pit defect.
Background technology
At present, in hot-strip production process, belt steel surface pit defect is the key factor affecting product surface quality, pit defect has higher incidence on think gauge (thickness G reatT.GreaT.GT 11.5mm) hot-rolled coil surface, especially in the steel grade production processes such as think gauge wheel steel, has high incidence.Car wheel structure parts generally adopt roll extrusion, spinning and Sheet Metal Forming Technology technology to be shaped, if belt steel surface has pit defect, then described band steel very easily produces the phenomenon that stress is concentrated in wheel arrangement forming process, causes layering and the cracking of steel plate.In addition, band steel finished surface pit defect all cannot be eliminated before and after spraying paint, and have impact on product appearance quality, have impact on the occupation rate of market of consumer products to a great extent.Therefore, the belt steel surface of polishing cleaning is very important to car wheel structure product product.
And cause the basic reason of belt steel surface pit defect to be that belt steel surface iron scale is blocked up, generally adopt the mode on manual polishing surface to eliminate belt steel surface pit defect in prior art, this mode is time-consuming, effort not only, inefficiency, and cost is higher.
Summary of the invention
For prior art Problems existing, embodiments provide a kind of process eliminating belt steel surface pit defect, by producing the process optimization of line to hot rolling, avoid the generation of belt steel surface pit defect from source.
Technical scheme of the present invention is achieved in that
The embodiment of the present invention provides a kind of process eliminating belt steel surface pit defect, and described method comprises:
The slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C;
Controlling roughing mills adopts the rolling mode of 3+5 passage to carry out roughing to described slab, carries out full passage dephosphorization by roughing operation to described slab;
Carry out finish rolling to the intermediate blank after roughing, controlling described intermediate blank entry temperature at finishing is 940-980 DEG C;
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25% ~ 30%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18% ~ 20%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18% ~ 20%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 45% ~ 50%;
Controlling the 7th finishing mill mill speed is 4.5 ~ 5.5m/s; Reduce the thickness of described belt steel surface iron scale.
In such scheme, the slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C and comprises:
It is 1130 ~ 1180 DEG C by the slab tapping temperature with steel described in Heating Furnace Control.
In such scheme, the rolling mode of described control roughing mills employing 3+5 passage carries out roughing to described slab and comprises:
First roughing mill adopts the rolling mode of 3 passes and the second roughing mill adopts the rolling mode of 5 passes, carries out roughing to described slab.
In such scheme, describedly by roughing operation, full passage dephosphorization is carried out to described slab and comprises:
By the 1st, 2,3 rolling pass entrances of the first roughing mill, dephosphorization is carried out to described slab, and by the 1st, 2,3,4,5 rolling pass entrances of the second roughing mill, dephosphorization is carried out to described slab.
In such scheme, described control described intermediate blank entry temperature at finishing is 940-980 DEG C and comprises: crossing steel speed by the delay table controlled between described second roughing mill and mm finishing mill unit is 5.0 ~ 6.0m/s, guarantees that described entry temperature at finishing is 940-980 DEG C.
In such scheme, the first interstand cooling water open amount between described control first finishing mill and the second finishing mill is 25% ~ 30% to comprise: by controlling the first interstand cooling (operating) water nozzle flow valve arranged between described first finishing mill and the second finishing mill, controlling described first interstand cooling water open amount is 25% ~ 30%.
In such scheme, the second interstand cooling water open amount between described control second finishing mill and the 3rd finishing mill is 18% ~ 20% to comprise: by controlling the second interstand cooling (operating) water nozzle flow valve arranged between described second finishing mill and the 3rd finishing mill, controlling described second interstand cooling water open amount is 18% ~ 20%.
In such scheme, the 3rd interstand cooling water open amount between described control the 3rd finishing mill and the 4th finishing mill is 18% ~ 20% to comprise: by controlling the 3rd interstand cooling (operating) water nozzle flow valve arranged between described 3rd finishing mill and the 4th finishing mill, controlling described 3rd interstand cooling water open amount is 18% ~ 20%.
In such scheme, the 4th interstand cooling water open amount between described control the 4th finishing mill and the 5th finishing mill is 45% ~ 50% to comprise: by controlling the 4th interstand cooling (operating) water nozzle flow valve arranged between described 4th finishing mill and the 5th finishing mill, controlling described 4th interstand cooling water open amount is 45% ~ 50%.
The invention provides a kind of process eliminating belt steel surface pit defect, described method comprises: the slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C; Controlling roughing mills adopts the rolling mode of 3+5 passage to carry out roughing to described slab, carries out full passage dephosphorization by roughing operation to described slab; Carry out finish rolling to the intermediate blank after roughing, controlling described intermediate blank entry temperature at finishing is 940-980 DEG C; The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25% ~ 30%; The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18% ~ 20%; The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18% ~ 20%; The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 45% ~ 50%; Controlling the 7th finishing mill mill speed is 4.5 ~ 5.5m/s.So, under the prerequisite not affecting other performances of product, significantly can reduce belt steel surface iron scale thickness, significantly reduce the incidence of belt steel surface pit defect.
Accompanying drawing explanation
The process schematic flow sheet of the elimination belt steel surface pit defect that Fig. 1 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the first process that Fig. 2 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the first process that Fig. 3 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the second process that Fig. 4 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the second process that Fig. 5 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the third process that Fig. 6 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the third process that Fig. 7 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the 4th kind of process that Fig. 8 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the 4th kind of process that Fig. 9 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the 5th kind of process that Figure 10 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the 5th kind of process that Figure 11 provides for the embodiment of the present invention;
The microstructure schematic diagram of the iron scale of the belt steel surface under the 6th kind of process that Figure 12 provides for the embodiment of the present invention;
The schematic surface of the band steel opening plate under the 7th kind of process that Figure 13 provides for the embodiment of the present invention.
Detailed description of the invention
In various embodiment of the present invention, in order to fundamentally solve the pit defect of belt steel surface, provide a kind of process eliminating belt steel surface pit defect, described method comprises: described method comprises: the slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C; Controlling roughing mills adopts the rolling mode of 3+5 passage to carry out roughing to described slab, carries out full passage dephosphorization by roughing operation to described slab; Carry out finish rolling to the intermediate blank after roughing, controlling described intermediate blank entry temperature at finishing is 940-980 DEG C; The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25% ~ 30%; The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18% ~ 20%; The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18% ~ 20%; The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 45% ~ 50%; Controlling the 7th finishing mill mill speed is 4.5 ~ 5.5m/s; Reduce the thickness of described belt steel surface iron scale.
Below by drawings and the specific embodiments, technical scheme of the present invention is described in further detail.
Embodiment one
The embodiment of the present invention provides a kind of process eliminating belt steel surface pit defect, and as shown in Figure 1, described method mainly comprises several step:
Step 110, the slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C;
In this step, before hot rolling, needing the slab to molten steel casting is formed to heat, is 1130 ~ 1180 DEG C by the slab tapping temperature with steel described in Heating Furnace Control, to guarantee that described band steel entry temperature at finishing can be reduced to 940-980 DEG C.
Step 111, controls roughing mills and adopts the rolling mode of 3+5 passage to carry out roughing to described slab, carry out full passage dephosphorization by roughing operation to described slab;
In this step, carry out roughing by roughing mills to described slab, described roughing mills adopts 3+5 rolling mode to carry out roughing to described slab; Wherein, described roughing mills comprises: the first roughing mill R1, the second roughing mill R2; Described first roughing mill R1 adopts the rolling mode of 3 passages, and described second roughing mill R2 adopts the rolling mode of 5 passages, carries out roughing to described slab.
Meanwhile, by roughing operation, full passage dephosphorization is carried out to described slab, ensure the removal effect of the raw iron scale of steel slab surface stove;
Particularly, by the 1st, 2, the 3 rolling pass entrances of the first roughing mill R1, dephosphorization is carried out to described slab, and by the 1st, 2,3,4, the 5 rolling pass entrances of the second roughing mill R2, dephosphorization is carried out to described slab.
Step 112, carries out finish rolling to the intermediate blank after roughing, and controlling described intermediate blank entry temperature at finishing is 940-980 DEG C;
In this step, the intermediate blank that described slab is formed after roughing, enters the entrance of finishing mill through the delay table between described second roughing mill R2 and mm finishing mill unit; Wherein, described intermediate blank when the motion of described delay table, control described roller-way to cross steel speed be 5.0 ~ 6.0m/s, temperature during to ensure that described intermediate blank enters finish rolling entrance is for 940-980 DEG C.
Here, the finish rolling dephosphorization apparatus before finish rolling entrance adopts the mode of double dephosphorization to carry out dephosphorization to institute's intermediate blank, to remove the secondary oxidation iron sheet that on rough rolling process and delay table, belt steel surface is formed, ensures the surface quality of band steel.
Step 113, the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25% ~ 30%;
Here, the first interstand cooling water device is provided with between described first finishing mill and the second finishing mill, by controlling the first interstand cooling (operating) water nozzle flow valve, described first interstand cooling water open amount is made to be 25% ~ 30%, to reduce surface temperature when described band steel runs between the first finishing mill and the second finishing mill, the control cincture steel scale on surface speed of growth, safeguard the surface state that the first precision rolling working roll is good, prevent the first precision rolling working roll surface film oxide to be destroyed the roll surface caused coarse.
Step 114, the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18% ~ 20%;
Here, the second interstand cooling water device is provided with between described second finishing mill and the 3rd finishing mill, by controlling the second interstand cooling (operating) water nozzle flow valve, described second interstand cooling water open amount is made to be 18% ~ 20%, to reduce the surface temperature of described band steel between the second finishing mill and the 3rd finishing mill, the control cincture steel scale on surface speed of growth, safeguard and the surface state that finish rolling second working roll is good prevent the second precision rolling working roll surface film oxide to be destroyed the roll surface caused coarse.
Step 115, the 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18% ~ 20%;
Here, the 3rd interstand cooling water device is provided with between described 3rd finishing mill and the 4th finishing mill, by controlling the 3rd interstand cooling (operating) water nozzle flow valve, described 3rd interstand cooling water open amount is made to be 18% ~ 20%, to reduce the surface temperature of described band steel between the 3rd finishing mill and the 4th finishing mill, the control cincture steel scale on surface speed of growth, safeguard and the surface state that the 3rd precision rolling working roll is good prevent the 3rd precision rolling working roll surface film oxide to be destroyed the roll surface caused coarse.
Step 116, the 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 45% ~ 50%;
Here, the 4th interstand cooling water device is provided with between described 4th finishing mill and the 5th finishing mill, by controlling the 4th interstand cooling (operating) water nozzle flow valve, described 4th interstand cooling water open amount is made to be 45% ~ 50%, to reduce the surface temperature of described band steel between the 4th finishing mill and the 5th finishing mill, the control cincture steel scale on surface speed of growth, safeguard and the surface state that the 4th precision rolling working roll is good prevent the 4th precision rolling working roll surface film oxide to be destroyed the roll surface caused coarse.
Here, between described 5th finishing mill and the 6th finishing mill, the 5th interstand cooling water device is provided with; Be provided with the 6th interstand cooling water device equally between the 6th finishing mill with the 7th finishing mill, the cooling water open amount that the process that the present embodiment provides only need control the first interstand cooling water device, the second interstand cooling water device, the 3rd interstand cooling water device, the 4th interstand cooling water device and the 5th interstand cooling water device can reach the control finish rolling interval belt steel surface iron scale thickness of expection, safeguards the object of the first precision rolling working roll, the second precision rolling working roll, the 3rd precision rolling working roll, the 4th precision rolling working roll roll surface kilter.
Step 117, controlling the 7th finishing mill mill speed is 4.5-5.5m/s;
In this step, when band steel moves to described 7th finishing mill, controlling the 7th finishing mill mill speed is 4.5 ~ 5.5m/s, to control described band steel in the section cooling district time of staying subsequently, reduces the thickness of described belt steel surface iron scale.
The process of the elimination belt steel surface pit defect that the embodiment of the present invention provides, producing Wiring technology by optimizing hot rolling, avoiding the generation of belt steel surface pit defect, improve strip surface quality and production efficiency from source.
Embodiment two
The process of the elimination belt steel surface pit defect that the present embodiment provides is produced line at 2250mm hot continuous rolling and has been carried out concrete enforcement, achieves the effect in anticipation.Here, the invention discloses following six kinds of processes, carry out contrast test, the Controlling Technology method in often kind of situation is different, particularly:
The first process: the actual tapping temperature 1168-1202 DEG C of control cincture plate slab, roughing adopts 1+5 rolling mode, carry out full passage de-scaling to described slab rough rolling, entry temperature at finishing 1002-1044 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described intermediate blank.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 28%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 20%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 20%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 49%;
The mill speed controlling the 7th finishing mill is 4.6m/s.By the first process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 2, the thickness of described iron scale is 15.5 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in Figure 3.Because in the first process, entry temperature at finishing is higher, causing belt steel surface iron scale partially thick, there is obvious pit defect in opening plate surface.
The second process: the actual tapping temperature 1131-1160 DEG C of control cincture plate slab, roughing adopts 1+5 rolling mode, carry out full passage de-scaling to described slab, entry temperature at finishing 942-980 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described slab.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 20%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 18%;
The speed controlling the 7th finishing mill is 5.5m/s.By the second process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 4, the thickness of described iron scale is 19.3 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in Figure 5.Due in the second process between finishing stand cooling water open amount not enough, causing belt steel surface iron scale partially thick, there is obvious pit defect in opening plate surface.
The third process: the actual tapping temperature 1134-1174 DEG C of control cincture plate slab, roughing adopts 1+5 rolling mode, carry out full passage de-scaling to described slab, entry temperature at finishing 940-978 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described slab.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 30%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 20%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 20%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 50%;
The speed controlling the 7th finishing mill is 3.8m/s.By the third process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 6, the thickness of described iron scale is 21.2 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in Figure 7.Due in the third process, finish rolling mill speed is lower, band steel finish rolling district and the floor cold roller-way time of staying longer, causing belt steel surface iron scale partially thick, there is obvious pit defect in opening plate surface.
4th kind of process: the actual tapping temperature 1130-1167 DEG C of control cincture plate slab, roughing adopts 3+5 rolling mode, carry out full passage de-scaling to described slab, entry temperature at finishing 940-977 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described slab.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 20%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 19%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 48%;
The speed controlling the 7th finishing mill is 4.5m/s.By the 4th kind of process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 8, the thickness of described iron scale is 10 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in Figure 9.Due in the 4th kind of process, technology point controls good, and belt steel surface iron scale is thinner, and opening plate surface finishing is clean, has no obvious pit defect.
5th kind of process: the actual tapping temperature 1135-1170 DEG C of control cincture plate slab, roughing adopts 3+5 rolling mode, carry out full passage de-scaling to described slab, entry temperature at finishing 944-980 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described slab.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 30%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 20%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 46%;
The speed controlling the 7th finishing mill is 5.5m/s.By the 5th kind of process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 10, the thickness of described iron scale is 8.85 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in figure 11.Due in the 5th kind of process, technology point controls good, and belt steel surface iron scale is thinner, and opening plate surface finishing is clean, has no obvious pit defect.
6th kind of process: the actual tapping temperature 1132-1169 DEG C of control cincture plate slab, roughing adopts 3+5 rolling mode, carry out full passage de-scaling to described slab, entry temperature at finishing 940-976 DEG C, the mode that finish rolling entrance is set to double de-scaling carries out double de-scaling to described slab.
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 27%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 19%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 20%;
The speed controlling the 7th finishing mill is 5.0m/s.By the 6th kind of process, the actual finishing temperature 820-860 DEG C of described band plate slab.In the sampling of strip width centre position, as shown in Figure 12, the thickness of described iron scale is 7.82 microns for belt steel surface iron scale microstructure and thickness; Band steel opening plate surface topography as shown in figure 13.Due in the 6th kind of process, technology point controls good, and belt steel surface iron scale is thinner, and opening plate surface finishing is clean, has no obvious pit defect.
To sum up, adopt the process of elimination belt steel surface pit defect that the embodiment of the present invention provides, can the thickness of effective control cincture steel scale on surface, the pit defect of elimination belt steel surface.
The above, be only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention, and all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.
Claims (9)
1. eliminate a process for belt steel surface pit defect, it is characterized in that, described method comprises:
The slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C;
Controlling roughing mills adopts the rolling mode of 3+5 passage to carry out roughing to described slab, carries out full passage dephosphorization by roughing operation to described slab;
Carry out finish rolling to the intermediate blank after roughing, controlling described intermediate blank entry temperature at finishing is 940-980 DEG C;
The the first interstand cooling water open amount controlled between the first finishing mill and the second finishing mill is 25% ~ 30%;
The the second interstand cooling water open amount controlled between the second finishing mill and the 3rd finishing mill is 18% ~ 20%;
The 3rd interstand cooling water open amount controlled between the 3rd finishing mill and the 4th finishing mill is 18% ~ 20%;
The 4th interstand cooling water open amount controlled between the 4th finishing mill and the 5th finishing mill is 45% ~ 50%;
Controlling the 7th finishing mill mill speed is 4.5 ~ 5.5m/s; Reduce the thickness of described belt steel surface iron scale.
2. the method for claim 1, is characterized in that, the slab tapping temperature controlling described band steel is 1130 ~ 1180 DEG C and comprises:
It is 1130 ~ 1180 DEG C by the slab tapping temperature with steel described in Heating Furnace Control.
3. the method for claim 1, is characterized in that, the rolling mode of described control roughing mills employing 3+5 passage carries out roughing to described slab and comprises:
First roughing mill adopts the rolling mode of 3 passes and the second roughing mill adopts the rolling mode of 5 passes, carries out roughing to described slab.
4. the method for claim 1, is characterized in that, describedly carries out full passage dephosphorization by roughing operation to described slab and comprises:
By the 1st, 2,3 rolling pass entrances of the first roughing mill, dephosphorization is carried out to described slab, and by the 1st, 2,3,4,5 rolling pass entrances of the second roughing mill, dephosphorization is carried out to described slab.
5. the method for claim 1, it is characterized in that, described control described intermediate blank entry temperature at finishing is 940-980 DEG C and comprises: crossing steel speed by the delay table controlled between described second roughing mill and mm finishing mill unit is 5.0 ~ 6.0m/s, guarantees that described entry temperature at finishing is 940-980 DEG C.
6. the method for claim 1, it is characterized in that, the first interstand cooling water open amount between described control first finishing mill and the second finishing mill is 25% ~ 30% to comprise: by controlling the first interstand cooling (operating) water nozzle flow valve arranged between described first finishing mill and the second finishing mill, controlling described first interstand cooling water open amount is 25% ~ 30%.
7. the method for claim 1, it is characterized in that, the second interstand cooling water open amount between described control second finishing mill and the 3rd finishing mill is 18% ~ 20% to comprise: by controlling the second interstand cooling (operating) water nozzle flow valve arranged between described second finishing mill and the 3rd finishing mill, controlling described second interstand cooling water open amount is 18% ~ 20%.
8. the method for claim 1, it is characterized in that, the 3rd interstand cooling water open amount between described control the 3rd finishing mill and the 4th finishing mill is 18% ~ 20% to comprise: by controlling the 3rd interstand cooling (operating) water nozzle flow valve arranged between described 3rd finishing mill and the 4th finishing mill, controlling described 3rd interstand cooling water open amount is 18% ~ 20%.
9. the method for claim 1, it is characterized in that, the 4th interstand cooling water open amount between described control the 4th finishing mill and the 5th finishing mill is 45% ~ 50% to comprise: by controlling the 4th interstand cooling (operating) water nozzle flow valve arranged between described 4th finishing mill and the 5th finishing mill, controlling described 4th interstand cooling water open amount is 45% ~ 50%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410542359.1A CN104307897B (en) | 2014-10-14 | A kind of process eliminating belt steel surface pit defect |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410542359.1A CN104307897B (en) | 2014-10-14 | A kind of process eliminating belt steel surface pit defect |
Publications (2)
| Publication Number | Publication Date |
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| CN104307897A true CN104307897A (en) | 2015-01-28 |
| CN104307897B CN104307897B (en) | 2017-01-04 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109226258A (en) * | 2018-09-05 | 2019-01-18 | 湖南华菱涟源钢铁有限公司 | A method of prevent medium high carbon hot-strip from generating roll marks |
| CN110000207A (en) * | 2019-03-29 | 2019-07-12 | 山东钢铁集团日照有限公司 | A kind of manufacturing method of high surface grade hot rolling acid-cleaning dual phase steel |
| CN110180904A (en) * | 2019-05-29 | 2019-08-30 | 北京首钢股份有限公司 | A kind of phosphorous BH steel Surfaces of Hot Rolled Strip point defects controlling method of Ultra-low carbon |
| CN110961466A (en) * | 2019-12-19 | 2020-04-07 | 北京首钢股份有限公司 | Production method of interstitial-free steel |
| CN111922103A (en) * | 2020-07-10 | 2020-11-13 | 首钢京唐钢铁联合有限责任公司 | Method and device for descaling and cooling rough rolling |
| CN112207138A (en) * | 2020-09-25 | 2021-01-12 | 攀钢集团西昌钢钒有限公司 | Method for stably controlling finish rolling temperature of high-grade pipeline steel |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101704026A (en) * | 2009-12-03 | 2010-05-12 | 南京钢铁股份有限公司 | Method for controlling pitting on surface of medium steel plate |
| CN101947557A (en) * | 2010-08-27 | 2011-01-19 | 攀钢集团钢铁钒钛股份有限公司 | Preparation method for reducing scales generated on surfaces of hot-rolled steel plates |
| CN102240677A (en) * | 2011-05-13 | 2011-11-16 | 河北省首钢迁安钢铁有限责任公司 | Method for solving indentation of salix-leaf-shaped iron sheet on surface of hot continuous rolling strip steel |
| CN102699030A (en) * | 2012-05-30 | 2012-10-03 | 东北大学 | Preparation method of sheet billet continuous casting and rolling easy-acid washing hot rolling strip steel |
| CN102896161A (en) * | 2012-10-22 | 2013-01-30 | 河北省首钢迁安钢铁有限责任公司 | Method for removing steel hot rolling oxidized iron sheets for boracic cold rolling |
| CN103752610A (en) * | 2013-12-25 | 2014-04-30 | 马钢(集团)控股有限公司 | 2250 hot continuous rolling producing method for improving surface quality of steel for automobile outer plate |
| CN103920729A (en) * | 2013-11-07 | 2014-07-16 | 首钢总公司 | Method for removing red rust defects of high-silicon type high-strength automobile plate |
| CN103949480A (en) * | 2014-04-28 | 2014-07-30 | 沈阳大学 | Method for controlling oxide scales on surfaces of easily-pickled hot-rolled strip steel |
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101704026A (en) * | 2009-12-03 | 2010-05-12 | 南京钢铁股份有限公司 | Method for controlling pitting on surface of medium steel plate |
| CN101947557A (en) * | 2010-08-27 | 2011-01-19 | 攀钢集团钢铁钒钛股份有限公司 | Preparation method for reducing scales generated on surfaces of hot-rolled steel plates |
| CN102240677A (en) * | 2011-05-13 | 2011-11-16 | 河北省首钢迁安钢铁有限责任公司 | Method for solving indentation of salix-leaf-shaped iron sheet on surface of hot continuous rolling strip steel |
| CN102699030A (en) * | 2012-05-30 | 2012-10-03 | 东北大学 | Preparation method of sheet billet continuous casting and rolling easy-acid washing hot rolling strip steel |
| CN102896161A (en) * | 2012-10-22 | 2013-01-30 | 河北省首钢迁安钢铁有限责任公司 | Method for removing steel hot rolling oxidized iron sheets for boracic cold rolling |
| CN103920729A (en) * | 2013-11-07 | 2014-07-16 | 首钢总公司 | Method for removing red rust defects of high-silicon type high-strength automobile plate |
| CN103752610A (en) * | 2013-12-25 | 2014-04-30 | 马钢(集团)控股有限公司 | 2250 hot continuous rolling producing method for improving surface quality of steel for automobile outer plate |
| CN103949480A (en) * | 2014-04-28 | 2014-07-30 | 沈阳大学 | Method for controlling oxide scales on surfaces of easily-pickled hot-rolled strip steel |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109226258A (en) * | 2018-09-05 | 2019-01-18 | 湖南华菱涟源钢铁有限公司 | A method of prevent medium high carbon hot-strip from generating roll marks |
| CN110000207A (en) * | 2019-03-29 | 2019-07-12 | 山东钢铁集团日照有限公司 | A kind of manufacturing method of high surface grade hot rolling acid-cleaning dual phase steel |
| CN110180904A (en) * | 2019-05-29 | 2019-08-30 | 北京首钢股份有限公司 | A kind of phosphorous BH steel Surfaces of Hot Rolled Strip point defects controlling method of Ultra-low carbon |
| CN110180904B (en) * | 2019-05-29 | 2021-04-27 | 北京首钢股份有限公司 | Control method for surface pitting defects of ultra-low carbon phosphorus-containing BH steel hot-rolled strip steel |
| CN110961466A (en) * | 2019-12-19 | 2020-04-07 | 北京首钢股份有限公司 | Production method of interstitial-free steel |
| CN111922103A (en) * | 2020-07-10 | 2020-11-13 | 首钢京唐钢铁联合有限责任公司 | Method and device for descaling and cooling rough rolling |
| CN111922103B (en) * | 2020-07-10 | 2022-07-15 | 首钢京唐钢铁联合有限责任公司 | Method and device for descaling and cooling rough rolling |
| CN112207138A (en) * | 2020-09-25 | 2021-01-12 | 攀钢集团西昌钢钒有限公司 | Method for stably controlling finish rolling temperature of high-grade pipeline steel |
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Address after: 100041 Shijingshan Road, Beijing, No. 68, No. Co-patentee after: Shougang Jingtang United Iron & Steel Co., Ltd. Patentee after: SHOUGANG GROUP Co.,Ltd. Address before: 100041 Shijingshan Road, Beijing, No. 68, No. Co-patentee before: Shougang Jingtang United Iron & Steel Co., Ltd. Patentee before: SHOUGANG Corp. |