CN111850586A - Heat treatment process of cold-rolled strip steel - Google Patents
Heat treatment process of cold-rolled strip steel Download PDFInfo
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- CN111850586A CN111850586A CN202010694976.9A CN202010694976A CN111850586A CN 111850586 A CN111850586 A CN 111850586A CN 202010694976 A CN202010694976 A CN 202010694976A CN 111850586 A CN111850586 A CN 111850586A
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G3/00—Apparatus for cleaning or pickling metallic material
- C23G3/02—Apparatus for cleaning or pickling metallic material for cleaning wires, strips, filaments continuously
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/68—Temporary coatings or embedding materials applied before or during heat treatment
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/088—Iron or steel solutions containing organic acids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
- B21B2001/221—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length by cold-rolling
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
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- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
The invention discloses a heat treatment process of cold-rolled strip steel, which belongs to the technical field of heat treatment, the scheme is that a hydrochloric acid solution is refrigerated by starting a semiconductor refrigerating sheet, the temperature of the hydrochloric acid solution is kept at-5 ℃, when an acid-washing carrier ball contacts a casting blank roll, the hydrochloric acid solution in the acid-washing carrier ball can be extruded by means of rapid expansion of a built-in rubber ball bag, so that the acid-washing carrier ball is acid-washed on the casting blank roll, on the other hand, the magnetic shielding state of the built-in magnet ball can be relieved by means of mutual separation of absolute magnetic hemispheres, the acid-washing carrier ball can be pulled to move upwards to the upper side of a separation plate by means of the attraction effect of a magnet block on the built-in magnet ball and the reset effect of an elastic traction guide rope, the hydrochloric acid solution can be sucked into the acid-washing carrier ball through an L-shaped guide hole along with the contraction of the built-in rubber, thereby continuously pickling the casting coil.
Description
Technical Field
The invention relates to the technical field of heat treatment, in particular to a heat treatment process of cold-rolled strip steel.
Background
The thickness of the cold-rolled strip steel and the sheet steel is 0.1-3mm generally, and the width is 100-2000 mm; the hot rolled strip steel or steel plate is used as raw material and is rolled into the finished product by a cold rolling mill at normal temperature. The heat treatment of cold-rolled steel strip refers to an operation process of obtaining desired properties (such as mechanical properties, workability, physical properties, chemical properties, etc.) by changing the texture of metal or alloy through heating, holding, and cooling of a workpiece.
In order to make metal workpieces have required mechanical properties, physical properties and chemical properties, heat treatment processes are often indispensable except for reasonable selection of materials and various forming processes. Heating (warming and holding of the overall heat treatment package) and cooling are two basic processes of treatment, with speed being one of the key process parameters. The speed also includes the heating speed and the cooling speed.
If the heating is sufficient and uniform, the quenching cooling speed has a decisive influence on the structure and the performance, generally, martensite with high residual compressive stress and high hardness is easily obtained when the cooling speed is high, martensite with lower hardness (reduced residual stress), martensite and non-martensite (bainite and pearlite) and non-martensite are obtained in sequence along with the reduction of the cooling speed, and the corresponding hardness is also reduced. The specific volume of the structure after quenching is increased, i.e., volume expansion, relative to the original pearlite structure before quenching, with the amount of expansion of martensite being the maximum. The main consequences of non-uniform cooling rates are non-uniform hardness, non-uniform deformation, large and non-uniform residual stresses, which in the severe cases may lead to excessive quenching deformation or cracking.
At present, in the process of heat treatment of cold-rolled steel strip, the cast blank coil needs to be pickled, hydrochloric acid is usually used, but in the actual pickling process, the cast blank coil is at a high temperature, so that the hydrochloric acid is easily promoted to volatilize, and the pickling efficiency is reduced.
Disclosure of Invention
1. Technical problem to be solved
Aiming at the problems in the prior art, the invention aims to provide a heat treatment process of cold-rolled strip steel, the scheme is that a hydrochloric acid solution is refrigerated by starting a semiconductor refrigerating sheet, the temperature of the hydrochloric acid solution is kept at-5 ℃, when an acid-washing carrier ball contacts a casting blank coil, the built-in rubber balloon is promoted to rapidly expand by virtue of thermal decomposition of ammonium chloride powder in the built-in rubber balloon, on one hand, the hydrochloric acid solution in the acid-washing carrier ball can be extruded out so as to carry out acid-washing on the casting blank coil, on the other hand, the magnetic shielding state of the built-in magnet ball can be relieved by virtue of mutual separation between magnetic-isolating hemispheres, the acid-washing carrier ball can be pulled by virtue of the attraction effect of the magnet block on the built-in magnet ball and the resetting effect of an elastic traction guide rope, the acid-washing carrier ball can be pulled to move upwards until a release plug passes, the hydrochloric acid solution can be sucked into the pickling carrier ball through the L-shaped guide holes, so that the built-in magnet ball is in a magnetic shielding state again, and the pickling carrier ball moves downwards again along with the increase of the mass, and the continuous pickling of the casting blank coil is realized.
2. Technical scheme
In order to solve the above problems, the present invention adopts the following technical solutions.
A heat treatment process of cold-rolled strip steel comprises the following steps:
s1, guiding the molten steel into a casting blank in a continuous casting machine, controlling the casting speed to be 35-50m/min, and then conveying the casting blank to a heating furnace for heating;
s2, pulling out the casting blank by using a withdrawal and straightening machine, cooling at the speed of 50-100 ℃/S under the atmosphere condition of nitrogen, rolling into a coil by using a coiling machine at the temperature of 550-600 ℃, removing oxide scale from the casting blank coil, coating an aluminum oxide separant on the casting blank after the oxide scale is taken out, and then coiling again;
s3, carrying out heat treatment on the casting blank coil coated with the release agent in the S2, then carrying out heat preservation for 10-20 h, carrying out annealing, and removing the release agent on the surface of the casting blank coil;
s4, rewinding the cast blank roll, removing the separant, putting the cast blank roll into a closed circulating pickling box, and carrying out acid removal pickling on the cast blank roll by using hydrochloric acid, so that the utilization rate of the hydrochloric acid is improved, and the pickling efficiency is improved;
s5, adding sulfuric acid and acetic acid into the closed circulating pickling tank, fully mixing the sulfuric acid and the acetic acid with hydrochloric acid, and then pickling the casting blank coil again;
and S6, after polishing and brushing the pickled strip steel, drying and coiling the strip steel, then carrying out warm rolling under the nitrogen atmosphere condition, removing the iron scale of the warm rolled strip, then, feeding the casting blank into a roughing mill for 5-8 times of reciprocating rolling to obtain an intermediate blank, and continuously feeding the intermediate blank into a finishing mill for 10-15 times of continuous rolling to obtain a finished product.
Further, the closed circulation pickling box in S4 includes a pickling outer box, a semiconductor refrigerating sheet is mounted at the right end of the pickling outer box in an embedded manner, a partition plate is fixedly connected to the inner wall of the pickling outer box, hydrochloric acid solution on the upper side of the partition plate is filled in the pickling outer box, a blank casting roll on the lower side of the partition plate is arranged in the pickling outer box, a sponge cushion layer is fixedly connected to the bottom end of the partition plate, a plurality of uniformly distributed and mutually communicated flow guide through holes are drilled at the outer ends of the partition plate and the sponge cushion layer, a pair of mutually abutting rubber sealing sheets is fixedly connected to the inner wall of the flow guide through holes, a plurality of uniformly distributed and elastic traction guide ropes passing through the flow guide through holes are fixedly connected to the inner top end of the pickling outer box, a pickling carrier ball is fixedly connected to the bottom end of the elastic traction guide ropes, the pickling carrier ball includes a pickling carrier ball, and a release plug fixedly connected with, the outer end of the release plug is provided with an L-shaped diversion hole communicated with the pickling carrier ball, the pickling carrier ball is internally provided with a built-in rubber ball bag, the outer end of the built-in rubber ball bag is fixedly connected with a plurality of uniformly distributed magnetism-insulating hemispheres, the built-in rubber ball bag is internally provided with a built-in magnet ball, a hydrochloric acid solution is refrigerated by starting a semiconductor refrigerating sheet, the temperature of the hydrochloric acid solution is kept at-5 ℃, when the pickling carrier ball contacts a casting blank roll, the built-in rubber ball bag is rapidly expanded by virtue of thermal decomposition of ammonium chloride powder in the built-in rubber ball bag, on one hand, the hydrochloric acid solution in the pickling carrier ball can be extruded to pickle the casting blank roll, on the other hand, by virtue of mutual separation of the magnetism-insulating hemispheres, the magnetic shielding state of the built-in magnet ball can be relieved, and by virtue of the attraction effect of the magnet blocks, the acid-washing carrier ball can be pulled to move upwards until the release plug passes through the flow guide through hole and then enters the upper side of the partition plate, and along with the contraction effect of the built-in rubber ball bag after the temperature is reduced, the hydrochloric acid solution can be sucked into the acid-washing carrier ball through the L-shaped flow guide hole, so that the built-in magnet ball is in a magnetic shielding state again, and the acid-washing carrier ball moves downwards along with the increase of the mass, and therefore continuous acid washing is carried out on the casting blank coil continuously.
Further, the top end in the pickling outer box is fixedly connected with a plurality of evenly distributed fiber soft guide thorns and an external sac membrane, the external capsule membrane is positioned between every two adjacent fiber soft guide thorns, carbon dioxide gas is filled between the external capsule membrane and the pickling carrying ball, and by means of the fiber soft guide thorns, on one hand, the roughness of the surface of the pickling carrying ball can be promoted by means of the fiber soft guide thorns when the pickling carrying ball moves upwards, thereby facilitating the liquefaction of the volatilized hydrogen chloride gas and water vapor to be attached to the surface of the catalyst, on the other hand, the hydrochloric acid solution which can be formed again promotes the fibers to be attached to the surfaces of the fibers in a soft and stabbing manner, can promote the flow of the hydrochloric acid solution when the casting blank coil is pickled, thereby improving the acid washing effect of the cast blank roll, and forcing the external capsule film to expand along with the temperature rise in the acid washing process by means of the external capsule film, and pushing the fiber soft guide stabs to recover to a dissilient state.
Further, the mounting hole that is located the division board downside is dug to pickling outer container left end, install the closed door in the mounting hole, through setting up mounting hole and closed door, can conveniently place and take out the cast blank book in to the pickling outer container.
Furthermore, the pickling outer box upper end is opened the chisel and is had the interpolation hole that is located the magnet piece left, add downthehole threaded connection and have the sealing plug, through setting up interpolation hole and sealing plug, can be when carrying out pickling again to the casting blank book, conveniently add sulphuric acid and acetic acid in the pickling outer box.
Further, casting blank book bottom is equipped with the support filter screen with pickling outer container inner wall fixed connection, the support filter screen is located the sealing plug downside, through setting up the support filter screen, can conveniently filter the remaining piece in casting blank book surface when the pickling, reduces its bottom pickling outer container and difficult quilt clear possibility.
Further, hemisphere cylindricality guiding gutter that elastic traction guiding rope outer end was excavated there are a plurality of evenly distributed, hemisphere cylindricality guiding gutter inner wall fixedly connected with a plurality of evenly distributed's water conservancy diversion fine rope, the one end fixedly connected with magnetism end ball that hemisphere cylindricality guiding gutter was kept away from to the water conservancy diversion fine rope, through setting up hemisphere cylindricality guiding gutter and water conservancy diversion fine rope, can make things convenient for the hydrochloric acid solution of division board upside slowly to low, and absorbed gradually by the sponge bed course, through setting up magnetism end ball, can be with the help of its suction effect to pull the fine rope of water conservancy diversion towards the downside, can carry out the water conservancy diversion to hydrochloric acid solution.
Furthermore, the built-in rubber saccule is filled with ammonium chloride powder, and by means of the ammonium chloride powder, the density of the built-in rubber saccule can be promoted to be higher than that of the hydrochloric acid solution to sink, and on the other hand, the volume of the built-in rubber saccule can be rapidly increased after the built-in rubber saccule is expanded, so that the release speed of the hydrochloric acid solution is improved.
Furthermore, the magnetism isolating hemisphere is made of Fe-Ni alloy materials, the Ni content of the magnetism isolating hemisphere is 80%, the magnetism isolating hemisphere can be made of Fe-Ni alloy, the magnetism isolating hemisphere can be enabled to have a magnetism isolating effect, the built-in magnet ball is enabled to be magnetically shielded by means of tight adhesion of the plurality of magnetism isolating hemispheres when the built-in rubber ball bag contracts, and the magnetic shielding state of the built-in magnet ball is relieved by means of the distance generated between the magnetism isolating hemispheres after the built-in rubber ball bag expands.
Further, the built-in magnet ball and the magnetic end ball are both made of single-side magnets, the magnetic end ball and the built-in magnet ball attract each other, the magnetic end ball and the magnet block repel each other, and the possibility that the built-in magnet ball and the magnetic end ball repel each other due to the fact that the position of the built-in magnet ball and the magnetic end ball changes in the up-and-down moving process can be reduced by using the single-side magnets to manufacture the built-in magnet ball and the magnetic end ball.
3. Advantageous effects
Compared with the prior art, the invention has the advantages that:
(1) the scheme is that the semiconductor refrigerating sheet is started to refrigerate the hydrochloric acid solution, the temperature of the hydrochloric acid solution is kept at-5 ℃, when the pickling carrier ball contacts a casting blank roll, the built-in rubber ball bag is heated and decomposed to enable the built-in rubber ball bag to expand rapidly, on one hand, the hydrochloric acid solution in the pickling carrier ball can be extruded out to pickle the casting blank roll, on the other hand, the magnetic shielding state of the built-in magnet ball can be relieved by means of mutual separation between magnetic insulation hemispheres, the pickling carrier ball can be pulled to move upwards by means of the attraction effect of the magnet blocks on the built-in magnet ball and the reset effect of the elastic traction guide rope until the release plug passes through the flow guide through hole and enters the upper side of the separation plate, and along with the contraction effect of the built-in rubber ball bag after the temperature is reduced, the hydrochloric acid solution can be sucked into the pickling carrier ball through the L-shaped flow guide, and the pickling carrier ball is moved downwards again along with the increase of the mass, so that the continuous pickling is continuously carried out on the casting blank coil.
(2) The pickling outer container inner top end fixedly connected with a plurality of evenly distributed's the soft thorn and external bag membrane of leading of fibre, external bag membrane is located between every two adjacent soft thorn of leading of fibre, it has carbon dioxide gas to fill between external bag membrane and the pickling year ball, lead the thorn with the help of the soft fibre, on the one hand can be when the pickling year ball shifts up, lead the degree of roughness that the thorn can promote the pickling year ball surface with the help of the soft thorn of fibre, thereby be favorable to volatile hydrogen chloride gas and vapor liquefaction to adhere to its surface, on the other hand, hydrochloric acid solution that can form once more makes the soft thorn of fibre to adhere to its surface, can be when rolling up the pickling to the casting blank, make the flow of hydrochloric acid solution, thereby improve the pickling effect to the casting blank roll, and can be along with the rising of the process temperature of pickling with the help of external bag membrane, force external bag membrane inflation, and.
(3) The left end of the pickling outer box is provided with a mounting hole positioned on the lower side of the partition plate, a sealing door is installed in the mounting hole, and a casting blank roll can be conveniently placed in and taken out of the pickling outer box by arranging the mounting hole and the sealing door.
(4) The pickling outer container upper end is opened the chisel and is had the interpolation hole that is located the magnet piece left, and the downthehole threaded connection of interpolation has the sealing plug, through setting up interpolation hole and sealing plug, can be when carrying out pickling again to the casting blank book, conveniently add sulphuric acid and acetic acid in to the pickling outer container.
(5) The bottom is rolled up to the casting blank is equipped with the support filter screen with pickling outer container inner wall fixed connection, supports the filter screen and is located the sealing plug downside, supports the filter screen through setting up, can conveniently filter the remaining piece of casting blank roll surface when the pickling, reduces its bottom pickling outer container and difficult quilt clear possibility.
(6) Elastic traction guide rope outer end cuts the hemisphere cylindricality guiding gutter that has a plurality of evenly distributed, hemisphere cylindricality guiding gutter inner wall fixedly connected with a plurality of evenly distributed's water conservancy diversion fine rope, the one end fixedly connected with magnetism end ball of hemisphere cylindricality guiding gutter is kept away from to water conservancy diversion fine rope, through setting up hemisphere cylindricality guiding gutter and water conservancy diversion fine rope, can make things convenient for the hydrochloric acid solution of division board upside slowly to flow down, and absorb gradually by the sponge bed course, through setting up magnetism end ball, can be with the help of some suction effect of it, thereby pull water conservancy diversion fine rope towards the downside, can carry out the water conservancy diversion to hydrochloric acid solution.
(7) The built-in rubber sacculus is filled with ammonium chloride powder, and through setting up ammonium chloride powder, can make built-in rubber sacculus's density be greater than hydrochloric acid solution and sink the end, on the other hand can be after its inflation, the volume increases rapidly to improve hydrochloric acid solution's release rate.
(8) The magnetism-insulating hemisphere is made of Fe-Ni alloy materials, the Ni content of the magnetism-insulating hemisphere is 80%, the magnetism-insulating hemisphere is made of Fe-Ni alloy, the magnetism-insulating hemisphere can be enabled to have a magnetism-insulating effect, the built-in rubber ball bag is tightly attached to the magnetism-insulating hemisphere when being contracted, the built-in magnet ball is enabled to be shielded by magnetism, and after the built-in rubber ball bag is expanded, the magnetic shielding state of the built-in magnet ball is relieved by means of the distance generated between the magnetism-insulating hemispheres.
(9) The built-in magnet ball and the magnetic end ball are both made of single-side magnets, the magnetic end ball and the built-in magnet ball are mutually attracted, and the magnetic end ball and the magnet block are mutually repelled.
Drawings
FIG. 1 is a cross-sectional view of a casting coil being pickled by an outer pickling box according to the present invention;
FIG. 2 is a cross-sectional view of an acid-pickled carrier ball of the present invention releasing a hydrochloric acid solution;
FIG. 3 is a cross-sectional view of the outer pickling tank of the present invention with hydrochloric acid solution added to the pickled pellets;
FIG. 4 is a cross-sectional view of the outer pickling tank of the present invention absorbing hydrochloric acid;
FIG. 5 is a cross-sectional view of the internal rubber balloon portion of the present invention;
FIG. 6 is a vertical cross-sectional view of the elastic traction leader of the present invention;
fig. 7 is a cross-sectional view of the elastic traction guide rope of the present invention in the transverse direction.
The reference numbers in the figures illustrate:
the device comprises an acid-washing outer box 1, a 101 closed door, a 102 sealing plug, a 2 separation plate, a 3 hydrochloric acid solution, a 4 casting blank roll, a 401 supporting filter screen, a 5 sponge cushion layer, a 6 flow guide through hole, a 7 elastic traction guide rope, a 701 hemispherical cylindrical flow guide groove, a 702 flow guide fiber rope, a 703 magnetic end ball, an 8 acid-washing carrier ball, a 9 outer-wrapping ball frame, a 10 release plug, an 11L-shaped flow guide hole, a 12 built-in rubber ball bag, a 13 absolute magnetic hemisphere, a 14 built-in magnet ball, a 15 magnet block, a 16 fiber soft guide thorn and a 17 outer-wrapping bag film.
Detailed Description
The drawings in the embodiments of the invention will be combined; the technical scheme in the embodiment of the invention is clearly and completely described; obviously; the described embodiments are only some of the embodiments of the invention; but not all embodiments, are based on the embodiments of the invention; all other embodiments obtained by a person skilled in the art without making any inventive step; all fall within the scope of protection of the present invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top/bottom", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "sleeved/connected," "connected," and the like are to be construed broadly, e.g., "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1:
a heat treatment process of cold-rolled strip steel comprises the following steps:
s1, guiding the molten steel into a casting blank in a continuous casting machine, controlling the casting speed to be 35-50m/min, and then conveying the casting blank to a heating furnace for heating;
s2, pulling out the casting blank by using a withdrawal and straightening machine, cooling at the speed of 50-100 ℃/S under the atmosphere condition of nitrogen, rolling into a coil by using a coiling machine at the temperature of 550-600 ℃, removing oxide scale from the casting blank coil, coating an aluminum oxide separant on the casting blank after the oxide scale is taken out, and then coiling again;
s3, carrying out heat treatment on the casting blank coil coated with the release agent in the S2, then carrying out heat preservation for 10-20 h, carrying out annealing, and removing the release agent on the surface of the casting blank coil;
S4, rewinding the cast blank roll, removing the separant, putting the cast blank roll into a closed circulating pickling box, and carrying out acid removal pickling on the cast blank roll by using hydrochloric acid, so that the utilization rate of the hydrochloric acid is improved, and the pickling efficiency is improved;
s5, adding sulfuric acid and acetic acid into the closed circulating pickling tank, fully mixing the sulfuric acid and the acetic acid with hydrochloric acid, and then pickling the casting blank coil again;
and S6, after polishing and brushing the pickled strip steel, drying and coiling the strip steel, then carrying out warm rolling under the nitrogen atmosphere condition, removing the iron scale of the warm rolled strip, then, feeding the casting blank into a roughing mill for 5-8 times of reciprocating rolling to obtain an intermediate blank, and continuously feeding the intermediate blank into a finishing mill for 10-15 times of continuous rolling to obtain a finished product.
Referring to fig. 1-5, the closed circulation pickling tank in S4 includes a pickling outer tank 1, a semiconductor refrigerating plate is embedded at the right end of the pickling outer tank 1, a partition plate 2 is fixedly connected to the inner wall of the pickling outer tank 1, a hydrochloric acid solution 3 is filled in the pickling outer tank 1 and is located above the partition plate 2, a cast blank roll 4 is arranged in the pickling outer tank 1 and is located below the partition plate 2, a sponge cushion 5 is fixedly connected to the bottom end of the partition plate 2, the volatile hydrogen chloride gas and water vapor can be absorbed by the low-temperature sponge cushion 5 to form the hydrochloric acid solution 3 again, a plurality of uniformly distributed and mutually communicated guide holes 6 are drilled at the outer ends of the partition plate 2 and the sponge cushion 5, a pair of mutually abutting rubber sealing plates is fixedly connected to the inner wall of the guide holes 6, a plurality of uniformly distributed and elastic traction guide ropes 7 penetrating through the guide holes 6 are fixedly connected to the top end, the bottom end of the elastic traction guide rope 7 is fixedly connected with an acid-washing carrier ball 8, the acid-washing carrier ball 8 comprises an acid-washing carrier ball 9, the upper end of the acid-washing carrier ball 9 is embedded with a release plug 10 fixedly connected with the elastic traction guide rope 7, the outer end of the release plug 10 is provided with an L-shaped guide hole 11 communicated with the acid-washing carrier ball 9 in a chiseled way, a built-in rubber ball bag 12 is arranged in the acid-washing carrier ball 9, the outer end of the built-in rubber ball bag 12 is fixedly connected with a plurality of uniformly distributed magnetic-insulated hemispheres 13, a built-in magnet ball 14 is arranged in the built-in rubber ball bag 12, the hydrochloric acid solution 3 is refrigerated by starting a semiconductor refrigerating sheet, the temperature is kept at-5 ℃, when the acid-washing carrier ball 9 contacts with the casting blank roll 4, the built-in rubber ball bag 12 is heated to decompose and promote the built-in rubber ball bag 12 to, on the other hand, the magnetic shielding state of the built-in magnet ball 14 can be released by the mutual separation of the magnetic-insulated hemispheres 13, the acid-washing carrier ball 8 can be pulled to move upwards by the attraction of the magnet blocks 15 to the built-in magnet ball 14 and the reset action of the elastic traction guide rope 7 until the release plug 10 passes through the flow guide through hole 6 and enters the upper side of the partition plate 2, the hydrochloric acid solution 3 can be sucked into the acid-washing carrier ball 9 through the L-shaped flow guide hole 11 along with the contraction action of the built-in rubber ball 12 after the temperature is reduced, the built-in magnet ball 14 is in the magnetic shielding state again, and the acid-washing carrier ball 8 moves downwards along with the increase of the mass, so that the continuous acid-washing of the casting blank coil 4 is continuously carried out.
Referring to fig. 2 and 4, the internal top end of the pickling outer box 1 is fixedly connected with a plurality of uniformly distributed fiber soft guide thorns 16 and external capsule membranes 17, the external capsule membranes 17 are positioned between every two adjacent fiber soft guide thorns 16, carbon dioxide gas is filled between the external capsule membranes 17 and the pickling carrier balls 9, by means of the fiber soft guide thorns 16, on one hand, when the pickling carrier balls 8 move upwards, the roughness of the surfaces of the pickling carrier balls 8 can be promoted by means of the fiber soft guide thorns 16, so that the volatile hydrogen chloride gas and the steam are favorably liquefied and attached to the surfaces of the pickling carrier balls, on the other hand, the fiber soft guide thorns 16 can be promoted to be attached to the surfaces of the carrier balls by means of the hydrochloric acid solution 3 which can be formed again, when the casting blank rolls 4 are pickled, the flow of the hydrochloric acid solution 3 can be promoted, so that the pickling effect on the casting blank rolls 4 is improved, and the external capsule membranes, and the fiber soft guide 16 is pushed to return to the dissilient state.
Referring to fig. 1 and 3, the left end of the pickling outer tank 1 is drilled with a mounting hole at the lower side of the partition plate 2, a closing door 101 is installed in the mounting hole, and by installing the mounting hole and the closing door 101, the casting blank roll 4 can be conveniently placed and taken out of the pickling outer box 1, an adding hole positioned on the left side of the magnet block 15 is arranged at the upper end of the pickling outer box 1 in a chiseled mode, a sealing plug 102 is connected in the adding hole in a threaded mode, through the arrangement of the adding hole and the sealing plug 102, when the casting blank roll 4 is pickled again, sulfuric acid and acetic acid can be conveniently added into the pickling outer box 1, a supporting filter screen 401 fixedly connected with the inner wall of the pickling outer box 1 is arranged at the bottom end of the casting blank roll 4, the supporting filter screen 401 is positioned at the lower side of the sealing plug 102, and by arranging the supporting filter screen 401, when pickling is conveniently carried out, the residual scraps on the surface of the casting blank coil 4 are filtered, so that the possibility that the scraps are not easy to clean at the bottom of the pickling outer box 1 is reduced.
Referring to fig. 6-7, the outer end of the elastic traction guide rope 7 is drilled with a plurality of uniformly distributed hemispherical cylindrical guide grooves 701, the inner wall of the hemispherical cylindrical guide groove 701 is fixedly connected with a plurality of uniformly distributed guide fiber ropes 702, one end of each guide fiber rope 702 away from the hemispherical cylindrical guide groove 701 is fixedly connected with a magnetic end ball 703, by arranging the hemispherical cylindrical guide grooves 701 and the guide fiber ropes 702, the hydrochloric acid solution 3 on the upper side of the partition plate 2 can flow slowly and be gradually absorbed by the sponge cushion 5, by arranging the magnetic end balls 703, the magnetic end balls 703 can have an attraction effect of 704, so that the guide fiber ropes 702 are drawn towards the lower side, and the hydrochloric acid solution 3 can be guided.
Referring to fig. 5 to 7, the inner rubber balloon 12 is filled with ammonium chloride powder, the ammonium chloride powder is arranged to make the density of the inner rubber balloon 12 greater than that of the hydrochloric acid solution 3 to sink to the bottom, and on the other hand, the volume of the inner rubber balloon is rapidly increased after the inner rubber balloon is expanded to improve the release speed of the hydrochloric acid solution 3, the magnetism-insulating hemisphere 13 is made of Fe-Ni alloy, the Ni content of the magnetism-insulating hemisphere 13 is 80%, the magnetism-insulating hemisphere 13 is made of Fe-Ni alloy to make the magnetism-insulating hemisphere 13 have magnetism-insulating effect, the plurality of magnetism-insulating hemispheres 13 are tightly attached to each other when the inner rubber balloon 12 is contracted to make the inner magnet ball 14 magnetically shielded, and after the inner rubber balloon 12 is expanded, the distance is generated between the magnetism-insulating hemispheres 13 to release the magnetic shielding state of the inner magnet ball 14, and the magnetic end ball 703 are both made of one-sided magnets, the magnetic end ball 703 and the built-in magnet ball 14 attract each other, the magnetic end ball 703 and the magnet block 15 repel each other, and the built-in magnet ball 14 and the magnetic end ball 703 are made of a single-sided magnet, so that the possibility of mutual repulsion between the built-in magnet ball 14 and the magnetic end ball 703 due to position change in the up-and-down movement process can be reduced.
The above; but are merely preferred embodiments of the invention; the scope of the invention is not limited thereto; any person skilled in the art is within the technical scope of the present disclosure; the technical scheme and the improved concept of the invention are equally replaced or changed; are intended to be covered by the scope of the present invention.
Claims (10)
1. A heat treatment process of cold-rolled strip steel is characterized by comprising the following steps: the method comprises the following steps:
s1, guiding the molten steel into a casting blank in a continuous casting machine, controlling the casting speed to be 35-50m/min, and then conveying the casting blank to a heating furnace for heating;
s2, pulling out the casting blank by using a withdrawal and straightening machine, cooling at the speed of 50-100 ℃/S under the atmosphere condition of nitrogen, rolling into a coil by using a coiling machine at the temperature of 550-600 ℃, removing oxide scale from the casting blank coil, coating an aluminum oxide separant on the casting blank after the oxide scale is taken out, and then coiling again;
s3, carrying out heat treatment on the casting blank coil coated with the release agent in the S2, then carrying out heat preservation for 10-20 h, carrying out annealing, and removing the release agent on the surface of the casting blank coil;
s4, rewinding the cast blank roll, removing the separant, putting the cast blank roll into a closed circulating pickling box, and carrying out acid removal pickling on the cast blank roll by using hydrochloric acid, so that the utilization rate of the hydrochloric acid is improved, and the pickling efficiency is improved;
S5, adding sulfuric acid and acetic acid into the closed circulating pickling tank, fully mixing the sulfuric acid and the acetic acid with hydrochloric acid, and then pickling the casting blank coil again;
and S6, after polishing and brushing the pickled strip steel, drying and coiling the strip steel, then carrying out warm rolling under the nitrogen atmosphere condition, removing the iron scale of the warm rolled strip, then, feeding the casting blank into a roughing mill for 5-8 times of reciprocating rolling to obtain an intermediate blank, and continuously feeding the intermediate blank into a finishing mill for 10-15 times of continuous rolling to obtain a finished product.
2. The heat treatment process for cold-rolled steel strip according to claim 1, characterized in that: airtight circulation pickling box in S4 includes pickling outer container (1), pickling outer container (1) right-hand member inlays to establish and installs the semiconductor refrigeration piece, pickling outer container (1) inner wall fixedly connected with division board (2), pickling outer container (1) intussuseption is filled with hydrochloric acid solution (3) that are located division board (2) upside, be equipped with in pickling outer container (1) and be located the cast blank book (4) of division board (2) downside, division board (2) bottom fixedly connected with sponge bed course (5), division board (2) and sponge bed course (5) outer end all cut water conservancy diversion through-hole (6) that have a plurality of evenly distributed and communicate each other, a pair of rubber packing piece that supports tightly each other of water conservancy diversion through-hole (6) inner wall fixedly connected with, top fixedly connected with a plurality of evenly distributed and the elastic traction who passes water conservancy diversion through-hole (6) lead rope (7) in pickling outer container (1), elastic traction conductor rope (7) bottom fixedly connected with pickling year ball (8), pickling year ball (8) carry ball (9) including the pickling, pickling year ball (9) upper end inlays establishes release stopper (10) of installing with elastic traction conductor rope (7) fixed connection, the L shape water conservancy diversion hole (11) that have and pickling year ball (9) to be linked together are opened and chiseled to release stopper (10) outer end, the pickling is carried and is equipped with built-in rubber sacculus (12) in ball (9), a plurality of evenly distributed's of built-in rubber sacculus (12) outer end fixedly connected with magnetic hemisphere (13) that insulate, be equipped with built-in magnet ball (14) in built-in rubber sacculus (12).
3. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: the pickling outer box is characterized in that a plurality of uniformly distributed fiber soft guide thorns (16) and external sac membranes (17) are fixedly connected to the inner top end of the pickling outer box (1), the external sac membranes (17) are located between every two adjacent fiber soft guide thorns (16), and carbon dioxide gas is filled between the external sac membranes (17) and the pickling carrier balls (9).
4. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: the left end of the pickling outer box (1) is provided with a mounting hole located on the lower side of the partition plate (2), and a sealing door (101) is installed in the mounting hole.
5. The heat treatment process for cold-rolled steel strip according to claim 1, characterized in that: an adding hole positioned on the left side of the magnet block (15) is formed in the upper end of the pickling outer box (1) in a chiseled mode, and a sealing plug (102) is connected to the inner thread of the adding hole in a threaded mode.
6. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: and a support filter screen (401) fixedly connected with the inner wall of the pickling outer box (1) is arranged at the bottom end of the cast billet roll (4), and the support filter screen (401) is positioned on the lower side of the sealing plug (102).
7. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: the outer end of the elastic traction guide rope (7) is provided with a plurality of uniformly distributed hemispherical cylindrical guide grooves (701), the inner wall of each hemispherical cylindrical guide groove (701) is fixedly connected with a plurality of uniformly distributed guide fine ropes (702), and one end of each guide fine rope (702) far away from each hemispherical cylindrical guide groove (701) is fixedly connected with a magnetic end ball (703).
8. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: the built-in rubber balloon (12) is filled with ammonium chloride powder.
9. The heat treatment process for cold-rolled steel strip according to claim 2, characterized in that: the magnetic isolation hemisphere (13) is made of Fe-Ni alloy materials, and the Ni content of the magnetic isolation hemisphere (13) is 80%.
10. The heat treatment process for cold-rolled steel strip according to claim 3, characterized in that: the built-in magnet ball (14) and the magnetic end ball (703) are both made of one-side magnets, the magnetic end ball (703) and the built-in magnet ball (14) attract each other, and the magnetic end ball (703) and the magnet block (15) repel each other.
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| CN113818024A (en) * | 2021-07-29 | 2021-12-21 | 江苏捷士金金属科技有限公司 | Metal sheet surface rust removal device |
| CN114081290A (en) * | 2021-10-09 | 2022-02-25 | 南京百米需供应链管理有限公司 | Pickup method of intelligent express cabinet and intelligent express cabinet |
| CN114104080A (en) * | 2022-01-26 | 2022-03-01 | 徐州艾力驰汽车配件有限公司 | Point collection type temperature regulation and control type automobile steering wheel |
| CN114752941A (en) * | 2022-04-15 | 2022-07-15 | 江苏正泰不锈钢产业有限公司 | Preparation method of ferritic stainless steel seamless steel pipe |
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