CN117702034A - Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels - Google Patents
Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels Download PDFInfo
- Publication number
- CN117702034A CN117702034A CN202211122193.9A CN202211122193A CN117702034A CN 117702034 A CN117702034 A CN 117702034A CN 202211122193 A CN202211122193 A CN 202211122193A CN 117702034 A CN117702034 A CN 117702034A
- Authority
- CN
- China
- Prior art keywords
- section
- strip steel
- jet
- post
- furnace
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 210
- 239000010959 steel Substances 0.000 title claims abstract description 210
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 56
- 238000010438 heat treatment Methods 0.000 claims abstract description 115
- 238000001816 cooling Methods 0.000 claims abstract description 107
- 238000007747 plating Methods 0.000 claims abstract description 66
- 238000002791 soaking Methods 0.000 claims abstract description 49
- 238000005406 washing Methods 0.000 claims abstract description 42
- 239000002253 acid Substances 0.000 claims abstract description 41
- 238000003303 reheating Methods 0.000 claims abstract description 37
- 239000002131 composite material Substances 0.000 claims abstract description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000005246 galvanizing Methods 0.000 claims abstract description 32
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 25
- 239000011701 zinc Substances 0.000 claims abstract description 25
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 23
- 238000005275 alloying Methods 0.000 claims abstract description 22
- 238000000137 annealing Methods 0.000 claims abstract description 21
- 230000006698 induction Effects 0.000 claims abstract description 20
- 238000005097 cold rolling Methods 0.000 claims abstract description 11
- 238000010583 slow cooling Methods 0.000 claims abstract description 10
- 238000004140 cleaning Methods 0.000 claims abstract description 9
- 238000003466 welding Methods 0.000 claims abstract description 9
- 239000007789 gas Substances 0.000 claims description 71
- 239000002912 waste gas Substances 0.000 claims description 44
- 238000002485 combustion reaction Methods 0.000 claims description 33
- 239000001257 hydrogen Substances 0.000 claims description 31
- 229910052739 hydrogen Inorganic materials 0.000 claims description 31
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 30
- 230000001681 protective effect Effects 0.000 claims description 26
- 238000007789 sealing Methods 0.000 claims description 26
- 238000002347 injection Methods 0.000 claims description 23
- 239000007924 injection Substances 0.000 claims description 23
- 238000004321 preservation Methods 0.000 claims description 18
- 229910052757 nitrogen Inorganic materials 0.000 claims description 15
- 230000005855 radiation Effects 0.000 claims description 15
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 14
- 229910000797 Ultra-high-strength steel Inorganic materials 0.000 claims description 11
- 239000000443 aerosol Substances 0.000 claims description 9
- 238000009413 insulation Methods 0.000 claims description 9
- 230000000149 penetrating effect Effects 0.000 claims description 8
- 238000010791 quenching Methods 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 6
- 238000005192 partition Methods 0.000 claims description 6
- 230000000171 quenching effect Effects 0.000 claims description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- 229910052760 oxygen Inorganic materials 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 5
- 239000000446 fuel Substances 0.000 claims description 4
- 238000002161 passivation Methods 0.000 claims description 4
- 238000005452 bending Methods 0.000 claims description 3
- 238000007602 hot air drying Methods 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 239000003915 liquefied petroleum gas Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 239000003345 natural gas Substances 0.000 claims description 3
- 238000005201 scrubbing Methods 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 3
- 239000010960 cold rolled steel Substances 0.000 claims 7
- 238000000034 method Methods 0.000 abstract description 17
- 230000008569 process Effects 0.000 abstract description 10
- 238000005554 pickling Methods 0.000 abstract description 8
- 239000000047 product Substances 0.000 description 39
- 238000005516 engineering process Methods 0.000 description 12
- 239000002918 waste heat Substances 0.000 description 9
- 239000012467 final product Substances 0.000 description 5
- 230000009471 action Effects 0.000 description 4
- 230000001680 brushing effect Effects 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 238000005507 spraying Methods 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910000794 TRIP steel Inorganic materials 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000009499 grossing Methods 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000008186 active pharmaceutical agent Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 239000000567 combustion gas Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 125000001741 organic sulfur group Chemical group 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 238000009966 trimming Methods 0.000 description 1
- 238000004506 ultrasonic cleaning Methods 0.000 description 1
Landscapes
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
A flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels sequentially comprises the following steps: uncoiling, welding, inlet looping, cleaning, central continuous post-treatment, intermediate looping, flattening, outlet looping, finishing and coiling; the central continuous post-treatment station sequentially comprises a jet radiant tube preheating section, a radiant tube heating section, a transverse magnetic induction heating section or a muffle furnace section, a jet radiant composite soaking section, a slow cooling section, a rapid cooling section and a reheating section; the reheating section is followed by a furnace nose section, a zinc pot section, an air knife section, an alloying heating section, an alloying soaking section, a cooling section after plating and a final water cooling section; or, the air-jet cooling section is connected to the final water-cooling section through a moving channel, an overaging section and a final air-jet cooling section; an acid washing section or an acid washing section and a flash plating section are arranged behind the final water cooling section. The treatment line provided by the invention has at least three or more than three selectable process paths, and can realize the production of five different types of high-strength steel including cold rolling annealing, pickling, flash plating, hot dip pure zinc and alloying hot dip galvanizing.
Description
Technical Field
The invention relates to the technical field of cold-rolled strip steel treatment, in particular to a flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steel.
Background
In order to meet the increasing market demands of high-strength steel, particularly ultrahigh-strength steel, a plurality of production lines capable of producing ultrahigh-strength steel are newly established, including a continuous annealing cold-rolled strip steel production line, a hot-dip galvanized strip steel (hereinafter referred to as GI) production line and an alloying hot-dip galvanized strip steel (hereinafter referred to as GA) production line. These lines are produced essentially by conventional processes and have disadvantages in many respects. The following description will be given:
conventional strip steel processing lines typically include the following stations in addition to the various looper stations: uncoiling, welding, cleaning, central continuous post-treatment, flattening, finishing and coiling, wherein a withdrawal and straightening station is further arranged between a flattening station and a finishing station on some treatment lines, a post-treatment station is arranged between the flattening station and the finishing station on some treatment lines, and a withdrawal and straightening station and a post-treatment station are simultaneously arranged between the flattening station and the finishing station on other treatment lines.
The central continuous post-treatment station described above typically includes a conventional preheating section-heating section-soaking section-slow cooling section-fast cooling section-Overaging (OA) section-air-jet cooling section and a final water-cooling section for producing continuously annealed cold rolled products, as shown in fig. 1.
And a reheating section is arranged between the quick cooling section and the overaging section of some treatment lines, and an acid washing section and a reheating section are simultaneously arranged between the quick cooling section and the overaging section of some units. In the production of GI products, the central continuous post-treatment station typically comprises in sequence the equipment of a common preheating section-heating section-soaking section-slow cooling section-fast cooling section-balanced heat preservation section-furnace nose section-zinc pot section-air knife section-post-plating cooling section-final water cooling section, as shown in fig. 2.
And a reheating section is arranged between the quick cooling section and the balanced heat preservation section in some GI processing lines, and an acid washing section and a reheating section are simultaneously arranged between the quick cooling section and the balanced heat preservation section in some units.
Some treatment lines have a movable post-plating quench section disposed within 10 meters above the air knife between the air knife section and a stationary post-plating quench section (typically in the upper half of the APC tower). In the production of GA products, the central continuous post-treatment station typically comprises in sequence the equipment of a common preheating section-heating section-soaking section-slow cooling section-fast cooling section-balanced heat-preserving section-furnace nose section-zinc pot section-air knife section-alloying heating section-alloying soaking section-stationary post-plating cooling section and final water cooling section, as shown in fig. 3.
And a reheating section is arranged between the quick cooling section and the balanced heat preservation section in some processing lines, and an acid washing section and a reheating section are simultaneously arranged between the quick cooling section and the balanced heat preservation section in some units. The movable channel section is also arranged above the air knife section, so that the switching of two or three products is realized, wherein the movable channel section (only cold-rolled product is produced), the quick cooling section (only GI product is produced) after movable plating and the alloying heating section (only GA product is produced) are arranged in parallel, and strip steel is usually cut off for product switching. And the production line for producing the GI products and the GA products adopts parallel arrangement of a quick cooling section (only the GI products are put into use) and an alloying heating section (only the GA products are put into use) after mobile plating, so that the switching of the two products is realized.
One common method for the common preheating section and the heating section is to heat by using a radiant tube, then heat the protective gas by using combustion waste gas discharged by the radiant tube through an external heat exchanger, and finally spray the protective gas on the surface of the strip steel to preheat the strip steel to about 200 ℃. The preheating method has the following advantages compared with the method of directly spraying the waste gas generated by the combustion of the radiant tube on the surface of the strip steel to preheat the strip steel:
(1) And the pollution of the combustion waste gas to the surface of the strip steel is eliminated. Certain amount of impurities such as tar, dust, organic sulfur and the like exist in the mixed gas and the coke oven gas, so that if the combustion waste gas is directly sprayed on the surface of the strip steel to preheat the strip steel, the surface of the strip steel is polluted, and particularly, the situation is avoided when the high-surface-quality plate strip is produced.
(2) The combustion waste gas contains a certain amount of oxygen (3% -5%), and the combustion waste gas is directly sprayed on the surface of the strip steel to easily cause oxidation on the surface of the strip steel, and the surface quality of the strip steel product can be influenced. The protective gas is heated by the heat exchanger outside the furnace and then sprayed to the surface of the strip steel, and the protective gas contains 3 to 7 percent of hydrogen, so that the oxidation phenomenon can not occur, and the fuel can be saved by about 10 percent by adopting the preheating mode.
However, this preheating technique still has the following drawbacks:
1) The exhaust temperature of combustion exhaust gas after preheating the strip steel is still higher, the exhaust gas exhaust temperature usually exceeds 350 ℃ when producing high-temperature annealing materials, a boiler or a superheated water heating device is required to be added for secondary utilization outside the furnace for waste heat of the combustion exhaust gas, the economic efficiency is obviously reduced, and the occupied area of equipment is large.
2) The ratio of directly utilizing energy to the strip steel is low, namely a great amount of heat is still taken away by waste gas after the strip steel is preheated (the higher the temperature of the waste gas after the strip steel is preheated, the more heat is taken away), and the burnt heat is not fully transmitted to the strip steel (namely, the primary utilization rate of the energy is low).
3) The temperature of the preheated strip steel is limited, and the temperature of the strip steel after preheating is difficult to exceed 250 ℃.
In addition, the conventional radiant tube heating process technology has the following disadvantages:
(1) Because the thermal inertia of the radiant tube heating furnace is large, when the thickness specification and the annealing target temperature change greatly, the temperature adjustment speed of the strip steel is low, the temperature control precision is poor, the production of ultra-high strength steel is very unfavorable, and the product quality loss is large.
(2) When the radiation tube is used for heating, the heating efficiency is low and the heating speed is low when the temperature is higher than 750 ℃, and the higher the heating temperature is, the lower the heat efficiency and the heating speed is, the lower the once direct utilization efficiency of corresponding energy is.
(3) The traditional continuous annealing process generally adopts a radiant tube for further heating when the strip steel is annealed at the temperature higher than 750 ℃, and because the thermal inertia of a radiant tube heating furnace is large, when the thickness specification and the annealing target temperature change greatly, the temperature adjustment of the strip steel is slow, the temperature control precision is poor, the production of ultra-high strength steel is very unfavorable, and the product quality loss is large;
(4) The temperature control performance of the radiant tube soaking furnace is poor, and because the thermal inertia of the radiant tube soaking furnace is large, when the thickness specification and the annealing target temperature change greatly, the soaking temperature of the strip steel is slowly adjusted, and the actual soaking temperature fluctuation of the strip steel is large.
Disclosure of Invention
The invention aims to design a flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels, which can realize the following purposes: 1) The temperature of the strip steel can be quickly preheated to at least 250 ℃ by fully utilizing the waste heat of the combustion waste gas of the radiant tube; 2) The cooling of the radiant tube combustion waste gas after the strip steel is fully preheated can be obviously and directly discharged, a boiler or a superheated water heating device is not required to be added for secondary utilization of the waste heat of the combustion waste gas, so that the investment is obviously reduced, and the occupied area is reduced; 3) The waste heat of the combustion waste gas of the radiant tube is basically transmitted to the strip steel, and the primary utilization rate of heat energy is high; 4) The transverse magnetic induction rapid heating is realized in the ultra-high temperature period, so that the heat energy utilization rate is improved; 5) The rapid adjustment of the annealing heating temperature and the soaking temperature of the strip steel can be realized; 6) The flexible production line special for high-strength steel can flexibly produce various new products such as cold rolling, hot dip pure zinc (GI), alloying hot dip Galvanizing (GA), cold rolling surface nickel plating or zinc plating, and the like, so that the production line can better meet market demands; 7) Because the atmosphere in the muffle furnace is independently controlled, the diffusion and enrichment of alloy elements on the surface of the high-strength steel are effectively controlled, so that the platability of the ultra-high-strength steel product can be greatly improved, and the surface quality of the ultra-high-strength hot-dip product can also be obviously improved; 8) The rapid heating technology is combined with the rapid cooling technology, and can be used for producing various advanced high-strength steel products with higher strength grades by adopting lower alloy components, so that the production cost can be reduced, and the mechanical properties of various super-high-strength steel products can be improved.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels sequentially comprises the following stations: uncoiling, welding, inlet looping, cleaning, central continuous post-treatment, intermediate looping, flattening, outlet looping, finishing and coiling; wherein,
the central continuous post-treatment station sequentially comprises a jet radiant tube preheating section, a radiant tube heating section, a transverse magnetic induction heating section or a muffle furnace section which are arranged in parallel, a jet radiant composite soaking section, a slow cooling section, a rapid cooling section and a reheating section; the rapid cooling section comprises a high-hydrogen cooling section or/and an aerosol cooling section or/and a water quenching cooling section;
the reheating section is followed by a furnace nose section, a zinc pot section, an air knife section, an alloying heating section, an alloying soaking section, a cooling section after plating and a final water cooling section; or, connecting to the final water-cooled section through a moving channel, an overaging section, a final air-jet cooling section;
an acid washing section or an acid washing section and a flash plating section can be sequentially arranged after the final water cooling section; the strip steel can be selected to pass through an acid washing section to produce cold-rolled acid washing products, can be bypassed to cross the acid washing section to produce cold-rolled annealed products, and can also be selected to enter a flash plating section to produce flash plating products such as flash nickel plating or flash zinc plating after being acid washed;
The heating section of the radiant tube burns natural gas or liquefied petroleum gas or gas fuel, high-temperature waste gas is generated in the combustion process,
the preheating section of the jet radiant tube utilizes the combustion waste gas of the heating section or/and the soaking section to exchange heat in the furnace to heat the recycled nitrogen-hydrogen protective gas, and then the nitrogen-hydrogen protective gas is jetted to the upper surface and the lower surface of the strip steel to realize forced convection heat exchange;
the radiant tube heating section is connected in series with a (parallel arranged selectable transverse magnetic induction heating section or muffle furnace section);
the jet-radiation composite soaking section adopts a mode of combining forced convection and radiation to quickly soak the strip steel, so that the uniformity of the strip steel temperature is improved, and the quick adjustment of the strip steel soaking temperature is realized;
the cold-rolled strip steel post-treatment production line adopts a jet radiant tube preheating section and simultaneously adopts rapid cooling treatment, then reheating and then galvanization or overaging treatment;
the furnace nose section is arranged in parallel with the moving channel, strip steel passes through the furnace nose section backwards and is produced into hot dip pure zinc or alloyed hot dip galvanized products, and strip steel passes through the moving channel and is produced into cold rolling annealing or pickling or flash plating products;
the processing line has at least three or more than three selectable process paths, and can realize the production of five different types of high-strength steel including cold rolling annealing, acid washing, flash plating, hot plating pure zinc and alloying hot galvanizing.
Further, an optional withdrawal and straightening station and/or a surface post-treatment station such as passivation or fingerprint resistance and the like are arranged between the flattening station and the outlet looper station, and the strip steel can be withdrawn and straightened and/or subjected to surface post-treatment.
Preferably, the muffle furnace section equipment is provided with sealing devices at the front and back, and is also provided with an atmosphere adjusting device, and the hydrogen content, the oxygen content and the dew point in the muffle furnace section equipment can be independently adjusted and controlled.
Preferably, a balanced heat preservation section device is arranged between the reheating section and the furnace nose section, and hot galvanizing is performed after heat preservation treatment is performed on the strip steel.
Preferably, a movable post-plating quick cooling section device is arranged between the air knife section and the post-plating cooling section, and the movable post-plating quick cooling section and the alloying heating device are arranged in parallel to realize quick cooling of the strip steel after plating of the hot-dip pure zinc high-strength steel product; preferably, the device of the quick cooling section after mobile plating is arranged within the range of 10 meters above the air knife section.
Preferably, a secondary reheating section device is arranged after the balanced heat preservation section, and the balanced heat preservation strip steel is subjected to secondary reheating and then hot galvanizing or overaging treatment.
Preferably, a pickling section device is arranged between the rapid cooling section and the reheating section, and comprises a pickling unit, a hot water scrubbing unit, a hot water rinsing unit and a hot air drying unit, so that the pickling of the surface of the strip steel is realized, the pickling section device can be used for removing an oxide layer on the surface of the strip steel after aerosol cooling or/and water quenching cooling, and the platability of the hot-dip pure zinc or alloyed hot dip galvanized product can be improved.
Preferably, after the acid washing section, a flash iron plating or flash nickel plating section device is arranged, and then reheating treatment is carried out, so that the platability of the ultra-high-strength strip steel is further improved.
Preferably, the mobile post-plating quick cooling section adopts a mobile air injection quick cooling device or a mobile aerosol cooling device.
The invention also provides a jet radiant tube preheating device, which comprises:
the radiant tube heating furnace is characterized in that a furnace top roller chamber is arranged above a furnace body, and a steering roller is arranged in the furnace top roller chamber;
the radiant tube waste gas collection chamber is connected with the radiant tube heating furnace body through a connecting pipeline;
a preheating furnace, comprising:
a connecting hole is formed in the side wall of the upper part of the preheating furnace body, and the preheating furnace body is communicated with the radiant tube waste gas collection chamber through a communicating pipe; the top end of the preheating furnace body is provided with a furnace throat which corresponds to the furnace top roller chamber of the radiant tube heating furnace and is used for the strip steel to pass through; the bottom of the preheating furnace body is provided with a strip steel inlet, an inlet sealing device and an inlet steering roller; the upper part of the preheating furnace body is provided with a preheating furnace gas collection chamber; the lower part of the furnace body is provided with a lower partition plate with a penetrating hole to form an exhaust gas collecting chamber, and the exhaust gas collecting chamber is connected with an exhaust gas fan through an exhaust gas discharge pipeline, and preferably, a control valve is arranged on the exhaust gas discharge pipeline;
The heat exchange and air injection bellows units are arranged on two sides below a preheating furnace air collection chamber in the preheating furnace body along the height direction of the furnace body, and a strip penetrating channel for the strip to pass through is formed in the middle of the heat exchange and air injection bellows units; each heat exchange and air injection bellows unit comprises,
the air box body is vertically provided with a plurality of heat exchange tubes, and a plurality of nozzles are arranged on one side surface of the air box body, which is opposite to the threading channel; an exhaust gas secondary mixing chamber communicated with the heat exchange tube is arranged between the upper and lower bellows bodies; the air box body is internally provided with a protective gas, preferably, the air box body is internally provided with a nitrogen-hydrogen protective gas;
the port of the inlet pipeline of the circulating fan is arranged in the threading channel, and the port of the outlet pipeline of the circulating fan is positioned in the bellows body;
the sealing device is used for the strip steel to pass through and is respectively arranged at the lower port of the strip passing channel and the strip passing holes of the upper and lower partition plates.
Preferably, the inlet sealing device and the sealing device through which the strip steel can pass are of a nitrogen sealing structure, a nitrogen sealing chamber is adopted, and a nitrogen injection pipeline is arranged on the nitrogen sealing chamber.
According to the jet radiant tube preheating device, the nitrogen and hydrogen protective gas which is circularly utilized is directly heated by adopting in-furnace heat exchange (the heat exchange is not arranged outside the furnace), and the heated nitrogen and hydrogen protective gas is sprayed to the upper surface and the lower surface of the strip steel at a high speed to realize rapid and efficient preheating of the strip steel by forced convection heat exchange; the radiant tube combustion waste gas enters the preheating furnace gas collection chamber from the radiant tube waste gas collection chamber through a communicating pipe, then passes through a heat exchanger chamber (the heat exchanger is not arranged outside the furnace) in the preheating furnace from top to bottom, and fully exchanges heat with the nitrogen-hydrogen protective gas in the shell pass through the tube pass combustion waste gas in the process to heat the nitrogen-hydrogen protective gas, so that the radiant tube combustion waste gas in the preheating furnace is not directly contacted with the strip steel all the time, and the oxidation of the surface of the strip steel is avoided; in addition, the preheating temperature of the strip steel is high by adopting the preheating device, at least up to 250 ℃ and above, and at least 50 ℃ higher than the temperature of the common preheating strip steel; if the arrangement quantity of the jet preheating units is enough, the temperature of the burning exhaust gas of the radiant tube discharged from the multistage preheating furnace can be generally lower than 200 ℃, the radiant tube can be directly discharged, and the secondary utilization of the waste heat of the burning exhaust gas can be carried out outside the furnace without additional investment at all.
The invention relates to a jet-radiation composite soaking device, which comprises:
the furnace body is internally provided with a composite heating body along the height direction; the composite heating body comprises a plurality of heating elements,
the inner wall of the shell of the heat preservation box body is provided with a heat preservation material; a mounting hole is arranged in the center of one side surface of the heat preservation box body;
the circulating fan is arranged at the mounting hole of the heat insulation box body, the air suction inlet of the circulating fan corresponds to the axis of the mounting hole, and the air outlet is arranged on the side surface of the shell;
the buffer cavity is arranged in the insulation box body at a position corresponding to the air suction opening of the circulating fan, the back surface of the buffer cavity is provided with a hot air outlet corresponding to the air suction opening of the circulating fan, and the front surface of the buffer cavity is provided with a hot air inlet; preferably, the buffer cavity and the high-temperature air injection bellows are of an integrated structure;
the two high-temperature air jet bellows are vertically and symmetrically arranged at two sides of a hot air inlet at the front side of the buffer cavity in the heat insulation box body to form a strip penetrating channel for strip steel to pass through; a plurality of rows of jet nozzles are arranged on one side surface of the two high-temperature jet bellows at two sides of the threading channel at intervals along the height direction, and a gap is arranged between n rows of jet nozzles, wherein n is more than or equal to 1; preferably, the diameter of the jet nozzle is 1/10-1/5 of the distance from the jet nozzle to the strip steel; more preferably, the jet nozzle adopts a round hole structure;
The radiant tubes are symmetrically arranged in the two high-temperature air injection bellows and comprise a connecting tube section for connecting a burner, a radiant tube section bent and extended from one end of the connecting tube section and a heat exchange tube section formed by extending and bending from one end of the radiant tube section; the radiant tube section corresponds to gaps arranged between n rows of jet nozzles in the high-temperature jet bellows, so as to form a jet-radiation alternating structure; preferably, the radiant tube section, the connecting tube section and the heat exchange tube section of the radiant tube are arranged in parallel.
The jet-radiation composite soaking device adopts a composite heating technology, and the composite heating technology can organically combine the high-speed jet-heating technology and the radiant tube heating technology, so that the technical advantages of the high-speed jet-heating technology and the radiant tube heating technology are fully exerted. The structure of the radiant tube is optimally designed, the radiant tube is arranged in the high-speed high-temperature jet air box, heat generated by burning gas of the radiant tube is rapidly transferred to the strip steel through a high-speed jet air mode and a radiation mode, the rapid heating of the strip steel is realized, the highest average heating speed of the strip steel with the speed of 1mm is not lower than 40 ℃/s, the length of a heating furnace can be greatly shortened, the heating section of a unit with the annual output of 30 ten thousand tons is about 2 pass, and the thermal inertia of a furnace body is reduced;
Secondly, the first step of the method comprises the steps of,the heat generated by the gas is transferred to the circulating gas (N 2 +H 2 ) The heat-conducting material is taken away, so that the exhaust temperature of the radiant tube can be reduced, the exhaust temperature of the radiant tube can be reduced by about 100 ℃ under the same condition, the heat efficiency of the radiant tube is improved by about 5%, the average working temperature of the radiant tube can be reduced, and the service life of the radiant tube is prolonged;
and the temperature of the heated circulating gas is uniform, so that the temperature distribution of the strip steel in the width direction in the heating process is uniform, and the temperature distribution of the strip steel in the width direction in the actual heating process is controlled to be +/-5 ℃ according to the uniformity of the strip steel in the width direction, thereby realizing the stable operation of the unit. The high-speed air injection and radiation composite heating technology can obviously improve the productivity of the existing unit and solve the problem of insufficient heating capacity on the production line.
The radiant tube of the jet-radiation composite soaking device has the functions of combustion radiation (namely, the high-temperature section of the radiant tube between two rows of nozzles) and a heat exchanger, and is used for heating circulating gas, so that the heat of the combustion gas in the radiant tube can be rapidly transferred to strip steel through forced heat exchange, the rapid heating of the strip steel is realized, the length of a heating furnace can be greatly shortened, and the thermal inertia of a large-scale vertical continuous annealing furnace body is reduced.
The difference with the traditional process is that: the invention has the advantages that:
1) The invention has at least three or more than three selectable process paths;
2) The invention can realize the production of five different types of high-strength steel, especially super-high-strength steel, including cold rolling annealing, acid washing, flash plating, hot plating pure zinc and alloying hot galvanizing;
3) According to the technical scheme, the five different types of ultra-high strength steel can be subjected to surface post-treatment such as withdrawal straightening or/and passivation or fingerprint resistance;
4) The invention is provided with the secondary reheating section equipment, thereby realizing the twice lifting of the temperature of the strip steel before hot galvanizing or overaging treatment, being capable of realizing the rapid cooling of third-generation high-strength steel (QP steel) products to lower temperature, then rapidly heating to higher temperature on the horse for long-time carbon redistribution treatment, and rapidly reheating to the temperature of a hot galvanizing zinc-entering pot for the second time after the treatment is finished, and performing galvanization treatment;
5) The technical scheme of the invention changes the common preheating section into the jet radiant tube preheating section, more precisely the high-temperature nitrogen-hydrogen protective gas jet radiant tube preheating section, which is one of the novelty, creativity and practicability of the invention, and the remarkable characteristics of the invention, which are different from the common preheating section, are as follows:
(1) the method has the advantages that compared with the traditional heat exchange outside the furnace, the method has less heat loss of the furnace body, more sufficient waste heat of combustion waste gas, higher heating efficiency and faster heating rate;
(2) In the preheating section, radiant tube combustion waste gas enters the preheating furnace gas collection chamber from the radiant tube waste gas collection chamber through a communicating pipeline, then passes through a heat exchanger chamber (the heat exchanger is not arranged outside the furnace) in the preheating section from top to bottom, and fully exchanges heat in the heat exchanger between the combustion waste gas passing through the tube pass and the nitrogen-hydrogen protective gas passing through the shell pass in the process to heat the nitrogen-hydrogen protective gas, so that the radiant tube combustion waste gas is not in direct contact with strip steel all the time in the preheating section, and the oxidation of the surface of the strip steel is avoided;
(3) the preheating temperature of the strip steel is high and at least can reach 250 ℃ or above, and is at least 50 ℃ higher than that of the common preheating strip steel;
(4) if the arrangement quantity of the jet preheating units is enough, the temperature of the burning exhaust gas of the radiant tube which is discharged from the multistage preheating section can be generally lower than 200 ℃, the radiant tube can be directly discharged, and the secondary utilization of the waste heat of the burning exhaust gas is carried out outside the furnace without additional investment at all.
6) According to the invention, the transverse magnetic induction heating section and the muffle furnace section are arranged between the radiant tube heating section and the jet-air radiation composite soaking section, and are arranged in parallel, the switching between the transverse magnetic induction heating section and the muffle furnace section is realized by cutting off strip steel and re-threading, and the muffle furnace section equipment is also provided with an atmosphere regulating device, so that the hydrogen content, the oxygen content and the dew point in the muffle furnace section equipment can be independently regulated and controlled.
7) According to the invention, the air injection radiation composite soaking section is adopted before the slow cooling section, and the forced convection and radiation combined mode is adopted to soak the strip steel, so that the temperature uniformity of the strip steel can be improved, the quick adjustment of the soaking temperature of the strip steel can be realized, and the fluctuation of the actual temperature of the strip steel in the soaking section can be reduced.
The novel and creative embodiment of the invention is realized by simultaneously using the jet radiant tube preheating section and the transverse magnetic induction rapid heating section between the radiant tube heating section and the jet radiant composite soaking section. The transverse magnetic induction rapid heating section is arranged between the radiant tube heating section and the jet-jet radiation composite soaking section, and has the beneficial effects that: (1) the rapid adjustment of the strip steel temperature can be realized, which is very critical to the production of high-strength steel, especially ultra-high-strength steel, and the quality loss of the strip steel caused by inconsistent strip temperature can be reduced; (2) the strip steel can be rapidly heated to a higher temperature, and the prior engineering realizes the heat treatment of heating to more than 880 ℃ through a radiant tube heating section and a transverse magnetic induction heating section; (3) the air jet radiation composite soaking section is matched, the temperature uniformity of the soaked strip steel is good, and the temperature uniformity along the width direction of the strip steel can be controlled within +/-5 ℃.
The invention has the beneficial effects that:
1) The waste heat generated by heating and soaking the radiant tube can be fully utilized on line, and the temperature of the strip steel can be preheated to at least 250 ℃;
2) The cooling of the radiant tube after the waste gas is combusted fully preheats the strip steel is obviously and directly discharged, a boiler or a superheated water heating device is not required to be added for secondary utilization outside the boiler, so that the investment is obviously reduced, and the occupied area is reduced;
3) The waste heat of the combustion waste gas of the radiant tube is basically transmitted to the strip steel, and the primary utilization rate of heat energy is high;
4) The rapid heating is realized during the ultra-high temperature period, so that the heat energy utilization rate can be improved;
5) The strip steel can be economically and rapidly heated to more than 880 ℃ when transverse magnetic induction heating is used, so that high-temperature annealing can be realized, and various ultra-high strength steels can be produced;
6) Due to the application of the transverse magnetic induction heating and jet-air radiation composite heating technology, the rapid adjustment of the strip steel heating temperature and soaking temperature can be realized;
7) The same production line can be used for producing continuous annealing DP steel, TRIP steel, QP steel, hot dip galvanized DP steel, TRIP steel, QP steel and other ultra-high-strength steel;
8) The martensitic ultra-high strength steel with the strength up to 1500MPa can be produced by adopting water mist cooling and acid washing, the surface quality is high, and the platability of the strip steel during hot galvanizing is good;
9) The invention combines the application of the rapid cooling technology, can adopt lower alloy components to produce various advanced high-strength steel products with higher strength grade, not only can reduce the production cost, but also can improve the mechanical properties of various super high-strength steel products, and obviously improves the market competitiveness of the high-strength steel products;
10 The invention can realize the production of five different types of high-strength steel, especially super-high-strength steel, such as cold rolling annealing, acid washing, flash plating, hot plating pure zinc and alloying hot galvanizing.
Drawings
FIG. 1 is a schematic diagram of a station arrangement of a conventional continuous annealing production line;
FIG. 2 is a station layout of a conventional hot dip Galvanizing (GI) line;
FIG. 3 is a station layout of a conventional Galvannealed (GA) production line;
FIG. 4 is a layout of the production line of embodiment 1 of the present invention;
FIG. 5 is a layout of the production line in accordance with embodiment 2 of the present invention;
FIG. 6 is a station layout of the production line of example 3 of the present invention;
FIG. 7 is a station layout of the production line of example 4 of the present invention;
FIG. 8 is a layout of the production line of embodiment 5 of the present invention;
fig. 9 is a production line station layout of embodiment 6 of the present invention.
FIG. 10 is a schematic diagram of a preheating device for spray radiant tubes according to an embodiment of the present invention;
Fig. 11 is a schematic structural view of a preheating furnace for injecting radiant tubes in an embodiment of the preheating device for injecting radiant tubes according to the present invention.
Fig. 12 is a schematic structural view 1 of an embodiment of a jet-radiation composite soaking device according to the present invention;
fig. 13 is a schematic structural view 2 of an embodiment of a jet-radiation composite soaking device according to the present invention;
fig. 14 is a schematic structural diagram of a composite heating body in an embodiment of the jet-propelled radiation composite soaking device according to the present invention;
FIG. 15 is a partial perspective view of a high temperature jet bellows in an embodiment of a jet-radiant composite soaking apparatus according to the present invention;
fig. 16 is a perspective view of a radiant tube in an embodiment of the jet-propelled radiant composite soaking device according to the present invention.
Detailed Description
The following is a further description of the practice of the invention, with reference to specific examples: it should be noted that, by applying the inventive concept, various production lines can be simplified and combined, only one embodiment is given in this example, and other embodiments are given in the present invention, even though all the group patent examples are given only in some embodiments, various combinations generated by selecting and not selecting the optional stations according to the inventive concept are within the scope of the present invention, and various production lines derived according to the inventive concept are also within the scope of the present invention. In addition, for conventional stations, such as cleaning stations comprising an alkali liquor spraying section, an alkali liquor brushing section, an electrolytic cleaning section, a hot water brushing or cold water abrasive particle roller brushing section and a hot water rinsing section, even the cleaning new technical equipment which is simplified and combined by adopting a high-pressure water jet brushing section, an ultrasonic cleaning section, a high-pressure cleaning section and the like is considered to be the production line of the invention, and the production line is also within the protection scope of the invention. As another example, finishing stations including trimming, oiling, etc., are also within the scope of the present invention.
Referring to fig. 4, the flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels comprises the following stations in sequence: uncoiling, welding, inlet looping, cleaning, central continuous post-treatment, intermediate looping, flattening, outlet looping, finishing and coiling; wherein,
the central continuous post-treatment station sequentially comprises a jet radiant tube preheating section, a radiant tube heating section, a transverse magnetic induction heating section or a muffle furnace section which are arranged in parallel, a jet radiant composite soaking section, a slow cooling section, a rapid cooling section and a reheating section; the rapid cooling section comprises a high-hydrogen cooling section or/and an aerosol cooling section or/and a water quenching cooling section;
the reheating section is followed by a furnace nose section, a zinc pot section, an air knife section, an alloying heating section, an alloying soaking section, a cooling section after plating and a final water cooling section; or, connecting to the final water-cooled section through a moving channel, an overaging section, a final air-jet cooling section;
an acid washing section or (acid washing section and flash plating section) can be sequentially arranged after the final water cooling section; the strip steel can be selected to pass through an acid washing section to produce cold-rolled acid washing products, can be bypassed to cross the acid washing section to produce cold-rolled annealed products, and can also be selected to enter a flash plating section to produce flash plating products such as flash nickel plating or flash zinc plating after being acid washed;
The heating section of the radiant tube burns natural gas or liquefied petroleum gas or gas fuel, high-temperature waste gas is generated in the combustion process,
the preheating section of the jet radiant tube utilizes the combustion waste gas of the heating section or/and the soaking section to exchange heat in the furnace to heat the recycled nitrogen-hydrogen protective gas, and then the nitrogen-hydrogen protective gas is jetted to the upper surface and the lower surface of the strip steel to realize forced convection heat exchange;
the radiant tube heating section is connected in series with (parallel selectable transverse magnetic induction heating section or muffle furnace section);
the jet-radiation composite soaking section adopts a mode of combining forced convection and radiation to quickly soak the strip steel, so that the uniformity of the strip steel temperature is improved, and the quick adjustment of the strip steel soaking temperature is realized;
the cold-rolled strip steel post-treatment production line adopts a jet radiant tube preheating section and simultaneously adopts rapid cooling treatment, then reheating and then galvanization or overaging treatment;
the furnace nose section is arranged in parallel with the moving channel, strip steel passes through the furnace nose section backwards and is produced into hot dip pure zinc or alloyed hot dip galvanized products, and strip steel passes through the moving channel and is produced into cold rolling annealing or pickling or flash plating products;
the processing line has at least three or more than three selectable process paths, and can realize the production of five different types of high-strength steel including cold rolling annealing, acid washing, flash plating, hot plating pure zinc and alloying hot galvanizing.
Referring to fig. 4, in embodiment 1 of the present invention, an optional withdrawal and straightening station and/or a surface post-treatment station such as passivation or fingerprint resistance is further disposed between the flattening station and the outlet looper station, and the strip steel may be withdrawn and/or surface post-treated.
Preferably, the muffle furnace section equipment is provided with sealing devices at the front and back, and is also provided with an atmosphere adjusting device, and the hydrogen content, the oxygen content and the dew point in the muffle furnace section equipment can be independently adjusted and controlled.
Referring to fig. 5, in embodiment 2 of the present invention, a balanced heat-preserving section device is further disposed between the reheating section and the furnace nose section, and hot galvanizing is performed after heat-preserving treatment is performed on the strip steel.
Referring to fig. 6, in embodiment 3 of the present invention, a mobile post-plating rapid cooling section device is further disposed between the air knife section and the post-plating cooling section, and the mobile post-plating rapid cooling section is disposed in parallel with the alloying heating device, so as to achieve rapid cooling of the strip steel after plating of the hot-dip galvanized pure high-strength steel product; preferably, the device of the quick cooling section after mobile plating is arranged within the range of 10 meters above the air knife section.
Referring to fig. 7, there is shown an embodiment 4 of the present invention, in which a secondary reheating stage apparatus is disposed after the equilibrium maintaining stage, and the equilibrium maintaining strip steel is secondarily reheated and then hot-dip galvanized or overaged in embodiment 4.
Referring to fig. 8, an embodiment 5 of the present invention is shown, in embodiment 5, an acid washing section device is disposed between the rapid cooling section and the reheating section, where the acid washing section device includes an acid washing unit, a hot water scrubbing unit, a hot water rinsing unit, and a hot air drying unit, so as to implement acid washing on the surface of the strip steel, and the acid washing section device can be used for removing an oxide layer on the surface of the strip steel after aerosol cooling or/and water quenching cooling, and can also improve the platability of the hot-dip pure zinc or alloyed hot dip galvanized product, especially the ultra-high strength strip steel.
Referring to fig. 9, which shows example 6 of the present invention, in example 6, it is preferable to arrange a flash iron or nickel plating stage apparatus after the acid washing stage, and then perform reheating treatment to further improve the platability of the ultra-high-strength steel strip.
Preferably, the mobile post-plating quick cooling section adopts a mobile air injection quick cooling device or a mobile aerosol cooling device.
Referring to fig. 10 and 11, the preheating device for the injection radiant tube according to the present invention comprises:
a radiant tube heating furnace 1, a furnace top roller chamber 101 is arranged above a furnace body, and a steering roller 102 is arranged in the furnace top roller chamber 101;
the radiant tube waste gas collection chamber 2 is connected with the furnace body of the direct fire furnace 1 through a connecting pipeline 21;
A preheating furnace 3 comprising:
a preheating furnace body 31, the upper side wall of which is provided with a connecting hole and is communicated with the radiant tube waste gas collection chamber 2 through a communicating pipe 32; a furnace throat 311 which corresponds to the furnace top roller chamber 101 of the radiant tube heating furnace 1 and is used for the strip steel to pass through is arranged at the top end of the preheating furnace body 31; the bottom of the preheating furnace body 31 is provided with a strip steel inlet, an inlet sealing device 33 and an inlet steering roller; the upper part in the preheating furnace body 31 is provided with a preheating furnace gas collection chamber 312; a lower partition 313 with a through hole is arranged at the lower part in the preheating furnace body 31 to form an exhaust gas collecting chamber 314, and is connected with an exhaust gas fan 35 through an exhaust gas discharge pipeline 34 and then discharged from a chimney 500;
a plurality of heat exchange and air injection bellows units 36 arranged on two sides below a preheating furnace gas collection chamber 312 in the preheating furnace body 31 along the height direction of the preheating furnace body 31, and a strip penetrating channel 315 for passing strip steel is formed in the middle; each heat exchange and air injection bellows unit 36 includes,
a bellows body 361 in which a plurality of heat exchanging tubes 362 are vertically arranged, and a plurality of nozzles 363 are arranged on one side surface of the bellows body 362 opposite to the threading passage 315; a waste gas secondary mixing chamber communicated with the heat exchange tube 362 is arranged between the upper and lower bellows bodies 361; the bellows 361 is filled with nitrogen-hydrogen protective gas;
A circulating fan 364, the inlet of which is arranged in the threading passage 315 and the outlet of which is arranged in the bellows 361;
the sealing device 37 through which the strip steel can pass is arranged at the lower port of the strip passing channel 315 and the strip passing hole of the lower partition 313.
Preferably, the inlet sealing device 33 and the sealing device 37 are of a nitrogen sealing structure, a nitrogen sealing chamber is adopted, and a nitrogen injection pipeline is arranged on the nitrogen sealing chamber.
Preferably, a control valve 38 is provided in the exhaust gas outlet conduit 34.
The strip steel 100 is turned by an inlet turning roller and then runs upwards, enters a preheating furnace 3 for preheating treatment after being sealed by an inlet sealing device, then enters a furnace top roller chamber, and enters a radiant tube heating furnace 1 after being turned by the turning roller; the radiant tube heating combustion waste gas enters a radiant tube waste gas collecting chamber and is communicated with a preheating furnace collecting chamber of the preheating furnace 1 through a communication pipeline, and the preheating furnace collecting chamber belongs to a closed collecting chamber, so that waste gas in the preheating furnace collecting chamber is ensured not to contact with the strip steel 100; the radiant tube combustion exhaust accumulates in the preheating furnace plenum, which is used to preheat its combustion air first.
Under the action of the pumping force of an exhaust gas fan, the combustion exhaust gas of the high-temperature radiant tubes in the preheating furnace gas collection chamber continuously passes through the jet air box units which are serially connected one by one, and heat exchange tubes (the tube side is the high-temperature combustion exhaust gas and the shell side is the nitrogen-hydrogen mixed gas) serving as heat exchangers are arranged in the jet air box units; after the nitrogen-hydrogen protective gas is heated by the radiant tube combustion waste gas through the heat exchanger, the nitrogen-hydrogen protective gas is blown to the upper surface and the lower surface of the strip steel under the action of the circulating fan to preheat the strip steel.
The radiant tube combustion waste gas flows through the heat exchange tube from top to bottom, and in the flowing process, the nitrogen-hydrogen protective gas sprayed circularly is heated by heat exchange, then enters a waste gas secondary mixing chamber between the jet air box units, is subjected to secondary mixing, performs homogenization treatment on the waste gas temperature, then enters the downstream furnace heat exchange and jet air box units until reaching the bottom nitrogen sealing device, and finally enters the waste gas collecting chamber.
The nitrogen-hydrogen protective gas passes through the heat exchange tube bundles and is heated and then is continuously sprayed to the upper surface and the lower surface of the strip steel from the nozzles under the action of the circulating fan to preheat the strip steel. The air suction port of the circulating fan is connected to the DS side and the WS side of the air injection bellows unit through a furnace pipeline, under the action of the circulating fan, the nitrogen-hydrogen mixed gas is sprayed to the surface of the strip steel and then is pumped out from two sides, and then is sprayed to the upper surface and the lower surface of the strip steel through the heat exchanger through the circulating fan, so that the nitrogen-hydrogen mixed gas is circularly sprayed to heat the strip steel.
Referring to fig. 12 to 16, the jet-radiation composite soaking device according to the present invention includes:
a furnace body 4 in which a composite heating body 5 is arranged in the height direction; the composite heating body 5 comprises a metal sheet and a metal sheet,
a heat-insulating box 51, the inner wall of which is provided with a heat-insulating material; a mounting hole is arranged in the center of one side surface of the heat preservation box body 51;
The circulating fan 52 is arranged at the mounting hole of the heat insulation box body 51, the air suction inlet 521 of the circulating fan corresponds to the axis of the mounting hole, and the air outlet 522 is arranged on the side surface of the casing;
the buffer cavity 53 is arranged in the insulation box 51 at a position corresponding to the air suction opening of the circulating fan 52, the back surface of the buffer cavity 53 is provided with a hot air outlet corresponding to the air suction opening of the circulating fan 52, and the front surface of the buffer cavity is provided with a hot air inlet;
the two high-temperature air jet bellows 54, 54' are vertically and symmetrically arranged at two sides of the hot air inlet at the front side of the buffer cavity 53 in the heat insulation box body 51 to form a strip penetrating channel 200 for the strip 100 to penetrate through; a plurality of rows of jet nozzles 55, 55 'are arranged on one side surface of the two high-temperature jet bellows 54, 54' positioned on two sides of the threading channel 100 at intervals along the height direction, and a gap 300 is arranged between n rows of jet nozzles, wherein n is more than or equal to 1;
the plurality of radiant tubes 56, 56 'are symmetrically arranged in the two high-temperature jet bellows 54, 54', and the radiant tubes 56 (radiant tubes 56 are exemplified by the same below) comprise a connecting tube section 561 for connecting with a burner, a radiant tube section 562 which is bent and extended from one end of the connecting tube section 561, and a heat exchange tube section 563 which is formed by extending and bending from one end of the radiant tube section 562; the radiant tube sections 562 correspond to the gaps 300 provided between the n rows of jet nozzles in the high temperature jet bellows 54 to form an alternating jet and radiant configuration.
Preferably, the buffer cavity and the high-temperature air injection bellows are of an integrated structure.
Preferably, the diameter of the jet nozzle is 1/10-1/5 of the distance from the jet nozzle to the strip steel.
Preferably, the jet nozzle adopts a round hole structure.
Preferably, the radiant tube adopts a space four-stroke structure to form four sections of tube sections which are arranged in parallel, wherein one of the tube sections is a radiant tube section, and the rest is a connecting tube section and a heat exchange tube section.
Example 1
A high-strength strip steel is prepared through uncoiling, welding, passing through inlet loop, washing, preheating to 280 deg.C, heating to 700 deg.C, transverse magnetic induction heating to 800 deg.C, jet-radiating for compounding soaking for 60 seconds, slow cooling to 675 deg.C, cooling to 260 deg.C, passing through longitudinal magnetic induction heater (reheating equipment, no need of starting, passing through moving channel, passing through overageing at 260 deg.C, cooling to 145 deg.C, water cooling to 45 deg.C, passing through intermediate loop, levelling, drawing, passing through outlet loop, finishing and coiling. The final product band steel has 453MPa of yield strength, 512MPa of tensile strength and 24% of elongation at break.
Example 2
A high-strength strip steel is prepared through uncoiling, welding, passing through inlet loop, washing, preheating to 280 deg.C, heating to 710 deg.C, transverse magnetic induction heating to 810 deg.C, jet radiation composite soaking for 60 seconds, slow cooling to 670 deg.C, cooling to 460 deg.C, passing through longitudinal magnetic induction heater (reheating equipment, no need of starting) and proportional heat preservation, immersing in zinc pot, hot galvanizing, controlling plating weight by air knife, cooling to 145 deg.C, passing through middle loop, levelling, passing through outlet loop, finishing and coiling. The yield strength of the final product strip steel is 912MPa, the tensile strength is 1093MPa, and the breaking elongation is 9%.
Example 3
A process for preparing high-strength band steel includes such steps as uncoiling band steel whose main chemical component (mass%) is 0.080-0.80% Si-1.7% Mn, welding, passing through inlet loopers, washing, preheating to 275 deg.C, heating to 845 deg.C, pre-oxidizing the surface of said band steel by a muffle furnace, spraying air-radiation for 60 seconds, cooling to 680 deg.C, cooling to 230 deg.C, heating to 465 deg.C, hot galvanizing, moving plating, cooling to 140 deg.C, cooling to room temp, passing through middle loopers, smoothing, passing through outlet loopers, finishing, and coiling. The yield strength of the final product is 765MPa, the tensile strength is 998MPa, and the breaking elongation is 14.9%.
Example 4
A high-strength strip steel is prepared through uncoiling, welding, passing through inlet loop, washing, preheating to 265 deg.C, heating to 800 deg.C, transverse magnetic induction, heating to 850 deg.C, spraying air, immersing for 60 seconds, cooling to 730 deg.C, cooling to 50 deg.C, heating to 230 deg.C, balancing, reheating (no equipment function), moving channel and overageing, cooling to 140 deg.C, cooling to room temperature, pickling, flash plating, smoothing, passing through middle loop, passing through outlet loop, finishing and coiling. The yield strength of the final product strip steel is 936MPa, the tensile strength is 1153MPa, and the elongation at break is 14%.
Example 5
A production line of the high-strength strip steel is shown in fig. 8, strip steel with the main chemical composition (mass%) of 0.155% C-0.32% Si-2.63% Mn is uncoiled, welded, passed through an inlet loop and cleaned, then preheated to 265 ℃ by a jet radiant tube preheating furnace, heated to 835 ℃, passed through a muffle furnace, subjected to jet-radiation composite soaking for 40 seconds at 835 ℃, slowly cooled to 755 ℃, water quenched to room temperature, pickled, heated to 230 ℃ by a reheating section, subjected to balanced heat preservation, then passed through a moving channel section, subjected to overaging treatment at about 220 ℃, finally subjected to jet-cooling to about 140 ℃, finally cooled to room temperature by water, passed through an intermediate loop, passed through an outlet loop after flattening, finished and coiled, and finally finished the production. The yield strength of the final product is 1228MPa, the tensile strength is 1501MPa, and the breaking elongation is 4.1%.
The flexible cold rolling post-treatment production line suitable for producing various high-strength strip steels not only can realize the rapid adjustment of annealing heating temperature, but also can realize the rapid adjustment of annealing soaking temperature, can flexibly produce various high-strength steels and ultrahigh-strength steels, has large market flexibility, and has very wide application prospect under the conditions of various types of the existing ultrahigh-strength steels and gradually increased market demands.
Claims (11)
1. A flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels is characterized by sequentially comprising the following stations: uncoiling, welding, inlet looping, cleaning, central continuous post-treatment, intermediate looping, flattening, outlet looping, finishing and coiling; wherein,
the central continuous post-treatment station sequentially comprises a jet radiant tube preheating section, a radiant tube heating section, a transverse magnetic induction heating section or a muffle furnace section which are arranged in parallel, a jet radiant composite soaking section, a slow cooling section, a rapid cooling section and a reheating section; the rapid cooling section comprises a high-hydrogen cooling section or/and an aerosol cooling section or/and a water quenching cooling section;
the reheating section is followed by a furnace nose section, a zinc pot section, an air knife section, an alloying heating section, an alloying soaking section, a cooling section after plating and a final water cooling section; or, connecting to the final water-cooled section through a moving channel, an overaging section, a final air-jet cooling section;
An acid washing section or an acid washing section and a flash plating section can be sequentially arranged after the final water cooling section; the strip steel can be selected to pass through an acid washing section to produce cold-rolled acid washing products, can be bypassed to cross the acid washing section to produce cold-rolled annealed products, and can also be selected to enter a flash plating section to produce flash plating products such as flash nickel plating or flash zinc plating after being acid washed;
the radiant tube heating section burns natural gas or liquefied petroleum gas or gas and other gas fuels;
the preheating section of the jet radiant tube utilizes the combustion waste gas of the heating section or/and the soaking section to exchange heat in the furnace to heat the recycled nitrogen-hydrogen protective gas, and then the nitrogen-hydrogen protective gas is jetted to the upper surface and the lower surface of the strip steel to realize forced convection heat exchange;
the radiant tube heating section is connected in series with a (parallel arranged selectable transverse magnetic induction heating section or muffle furnace section);
the jet-radiation composite soaking section adopts a mode of combining forced convection and radiation to quickly soak the strip steel, so that the uniformity of the strip steel temperature is improved, and the quick adjustment of the strip steel soaking temperature is realized;
the cold-rolled strip steel post-treatment production line adopts a jet radiant tube preheating section and simultaneously adopts rapid cooling treatment, then reheating and then galvanization or overaging treatment;
The furnace nose section is arranged in parallel with the moving channel, the strip steel passes through the furnace nose section backwards to produce hot dip pure zinc or alloyed hot dip galvanized products, and the strip steel passes through the moving channel to produce cold rolling annealing or acid washing or flash plating products.
2. The flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steel according to claim 1, wherein an optional withdrawal and straightening station and/or a surface post-treatment station such as passivation or fingerprint resistance are further arranged between the flattening station and the outlet looper station, and the strip steel can be subjected to withdrawal and/or surface post-treatment.
3. The flexible post-treatment production line for cold-rolled steel strips, which is suitable for producing various high-strength steel strips, according to claim 1 or 2, wherein the muffle section is provided with sealing devices at the front and back, and is also provided with an atmosphere adjusting device, and the hydrogen content, the oxygen content and the dew point in the muffle section can be independently adjusted and controlled.
4. A flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels according to claim 1, 2 or 3, wherein a balanced heat-preserving section is further arranged between the reheating section and the furnace nose section, and the strip steel is subjected to heat-preserving treatment and then hot galvanizing.
5. The flexible post-treatment production line for cold-rolled steel strips suitable for producing various high-strength steel strips according to any one of claims 1 to 4, wherein a mobile post-plating quick cooling section is further arranged between the air knife section and the post-plating cooling section, and the mobile post-plating quick cooling section is arranged in parallel with alloying heating, so that the quick cooling of the steel strips after plating of hot-dip pure zinc high-strength steel products is realized; preferably, a mobile plating post-fast cooling section is arranged within a range of 10 meters above the air knife section.
6. The post-treatment production line for flexible cold-rolled steel strips suitable for producing various high-strength steels according to any one of claims 1 to 5, characterized in that a secondary reheating section is arranged after the balanced heat-preserving section, and the balanced heat-preserving steel strips are subjected to secondary reheating and then hot galvanizing or overaging treatment.
7. The flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steel according to any one of claims 1 to 6, wherein an acid washing section is arranged between the rapid cooling section and the reheating section, and the acid washing section equipment comprises an acid washing unit, a hot water scrubbing unit, a hot water rinsing unit and a hot air drying unit, so that the acid washing of the strip steel surface is realized, the strip steel surface can be used for removing an oxide layer on the strip steel surface after aerosol cooling or/and water quenching cooling, and the platability of the high-strength strip steel, particularly the ultra-high-strength strip steel, can be improved for hot-dip galvanized pure zinc or alloyed hot dip galvanized products.
8. The flexible post-treatment production line for cold-rolled steel strips suitable for producing various high-strength steel strips according to claim 7, wherein the plating iron or nickel plating section is arranged after the acid washing section and then the reheating treatment is carried out, so that the platability of the ultra-high-strength steel strips is further improved.
9. The flexible post-treatment production line for cold-rolled steel strips suitable for producing various high-strength steels according to any one of claims 1 to 8, wherein the mobile post-plating quick cooling section adopts mobile air injection quick cooling or mobile aerosol cooling.
10. A spray radiant tube preheating device for a cold rolled steel strip post-treatment line according to any one of claims 1 to 9, comprising:
the radiant tube heating furnace is characterized in that a furnace top roller chamber is arranged above a furnace body, and a steering roller is arranged in the furnace top roller chamber;
the radiant tube waste gas collection chamber is connected with the radiant tube heating furnace body through a connecting pipeline;
a preheating furnace, comprising:
a connecting hole is formed in the side wall of the upper part of the preheating furnace body, and the preheating furnace body is communicated with the radiant tube waste gas collection chamber through a communicating pipe; the top end of the preheating furnace body is provided with a furnace throat which corresponds to the furnace top roller chamber of the radiant tube heating furnace and is used for the strip steel to pass through; the bottom of the preheating furnace body is provided with a strip steel inlet, an inlet sealing device and an inlet steering roller; the upper part of the preheating furnace body is provided with a preheating furnace gas collection chamber; a lower partition plate with a penetrating hole is arranged at the lower part in the preheating furnace body to form an exhaust gas collecting chamber and is connected with an exhaust gas fan through an exhaust gas discharge pipeline; a control valve is arranged on the waste gas discharge pipeline;
The heat exchange and air injection bellows units are arranged on two sides below a preheating furnace air collection chamber in the preheating furnace body along the height direction of the furnace body, and a strip penetrating channel for the strip to pass through is formed in the middle of the heat exchange and air injection bellows units; each heat exchange and air injection bellows unit comprises,
the air box body is vertically provided with a plurality of heat exchange tubes, and a plurality of nozzles are arranged on one side surface of the air box body, which is opposite to the threading channel; an exhaust gas secondary mixing chamber communicated with the heat exchange tube is arranged between the upper and lower bellows bodies; the bellows body is filled with a protective gas, preferably a nitrogen-hydrogen protective gas;
the port of the inlet pipeline of the circulating fan is arranged in the threading channel, and the port of the outlet pipeline of the circulating fan is positioned in the bellows body;
the sealing device is used for allowing the strip steel to pass through and is respectively arranged at the lower port of the strip threading channel and the strip threading hole of the lower partition plate; preferably, the inlet sealing device and the sealing device through which the strip steel can pass are of a nitrogen sealing structure, a nitrogen sealing chamber is adopted, and a nitrogen injection pipeline is arranged on the nitrogen sealing chamber.
11. A jet-radiation composite soaking apparatus for a cold-rolled steel strip post-treatment line according to any one of claims 1 to 9, characterized by comprising:
the furnace body is internally provided with a composite heating body along the height direction; the composite heating body comprises a plurality of heating elements,
The inner wall of the shell of the heat preservation box body is provided with a heat preservation material; a mounting hole is arranged in the center of one side surface of the heat preservation box body;
the circulating fan is arranged at the mounting hole of the heat insulation box body, the air suction inlet of the circulating fan corresponds to the axis of the mounting hole, and the air outlet is arranged on the side surface of the shell;
the buffer cavity is arranged in the insulation box body at a position corresponding to the air suction opening of the circulating fan, the back surface of the buffer cavity is provided with a hot air outlet corresponding to the air suction opening of the circulating fan, and the front surface of the buffer cavity is provided with a hot air inlet; preferably, the buffer cavity and the high-temperature air injection bellows are of an integrated structure;
the two high-temperature air jet bellows are vertically and symmetrically arranged at two sides of a hot air inlet at the front side of the buffer cavity in the heat insulation box body to form a strip penetrating channel for strip steel to pass through; a plurality of rows of jet nozzles are arranged on one side surface of the two high-temperature jet bellows at two sides of the threading channel at intervals along the height direction, and a gap is arranged between n rows of jet nozzles, wherein n is more than or equal to 1; preferably, the diameter of the jet nozzle is 1/10-1/5 of the distance from the jet nozzle to the strip steel; more preferably, the jet nozzle adopts a round hole structure;
the radiant tubes are symmetrically arranged in the two high-temperature air injection bellows and comprise a connecting tube section for connecting a burner, a radiant tube section bent and extended from one end of the connecting tube section and a heat exchange tube section formed by extending and bending from one end of the radiant tube section; the radiant tube section corresponds to gaps arranged between n rows of jet nozzles in the high-temperature jet bellows, so as to form a jet-radiation alternating structure; preferably, the radiant tube section, the connecting tube section and the heat exchange tube section of the radiant tube are arranged in parallel.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211122193.9A CN117702034A (en) | 2022-09-15 | 2022-09-15 | Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels |
| PCT/CN2023/119209 WO2024056085A1 (en) | 2022-09-15 | 2023-09-15 | Rapid heat treatment production line of strip steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211122193.9A CN117702034A (en) | 2022-09-15 | 2022-09-15 | Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117702034A true CN117702034A (en) | 2024-03-15 |
Family
ID=90161217
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211122193.9A Pending CN117702034A (en) | 2022-09-15 | 2022-09-15 | Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117702034A (en) |
-
2022
- 2022-09-15 CN CN202211122193.9A patent/CN117702034A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105088073B (en) | 600MPa grades of high-elongation hot-dip aluminizing zincs of yield strength and color coated steel sheet and its manufacture method | |
| CN105063484B (en) | 500MPa grades of high-elongation hot-dip aluminizing zincs of yield strength and color coated steel sheet and its manufacture method | |
| CN101812578B (en) | Flexible strip processing line suitable for producing various high-strength steel | |
| CN101812579B (en) | Flexible strip steel treating line suitable for producing various high-strength steel | |
| KR101862206B1 (en) | Method of producing galvannealed steel sheet | |
| CN106715726A (en) | Method and apparatus for producing high-strength hot-dipped galvanized steel sheet | |
| CN101270409A (en) | Anneal technique for producing SPCC steel grade with zincing wire annealing oven | |
| CN105074021B (en) | Continuous fusion galvanizing device | |
| CN1176668A (en) | Primary cooling method in continuously annealing steel strip | |
| CN108220566A (en) | Compact fine grain high-strength plate output strip line flexible manufacturing method | |
| CN113403462B (en) | Preparation method of green-peel steel with yield strength of 700-1000 MPa | |
| CN101660091A (en) | Full hard hot dip galvanized steel plate with high strength and good surface quality and production method thereof | |
| CN117702034A (en) | Flexible cold-rolled strip steel post-treatment production line suitable for producing various high-strength steels | |
| CN117737633A (en) | Cold-rolled strip steel flexible aftertreatment production line suitable for producing various high-strength steels | |
| CN117737398A (en) | Flexible post-treatment line suitable for producing various ultra-high-strength strip steels | |
| CN117737399A (en) | Flexible cold rolling post-treatment production line suitable for producing various ultra-high-strength strip steels | |
| CN117737358A (en) | Multipurpose high-strength steel production line | |
| WO2024056085A1 (en) | Rapid heat treatment production line of strip steel | |
| CN117737634A (en) | Flexible production line for producing various high-strength/ultrahigh-strength steel | |
| CN117737635A (en) | Flexible cold-rolled strip steel post-treatment line suitable for producing various high-strength steel | |
| CN117702035A (en) | Flexible cold-rolled strip steel post-treatment line suitable for producing various high-strength steel | |
| CN117701869A (en) | Continuous annealing or hot galvanizing dual-purpose high-strength strip steel production line | |
| CN117737396A (en) | Flexible cold rolling post-treatment production line suitable for producing various ultra-high strength strip steels | |
| CN117737630A (en) | Quick hot galvanizing high-strength strip steel production line | |
| CN117701872A (en) | Continuous annealing or hot galvanizing dual-purpose ultra-high-strength strip steel production line |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |