Ribbed steel bar hot rolling method and equipment

Abstract

The invention discloses a ribbed steel bar hot rolling method and device, and belongs to the technical field of metal hot rolling machining.The ribbed steel bar hot rolling device comprises a hot rolling rack, an intermediate rolling mill and a finishing mill are installed at the top of the hot rolling rack, rolling racks are connected to the positions, corresponding to the rear portions of the intermediate rolling mill and the finishing mill, of the top of the hot rolling rack, and sleeving assemblies are connected to the rolling racks; the inner side of the sleeving assembly is rotationally connected with pretreatment assemblies, the multiple pretreatment assemblies are sleeved with the same torsion assembly, and the torsion assembly is used for driving the multiple pretreatment assemblies to rotate on the inner side of the sleeving assembly at the same time. The processing in the finish rolling stage is more stable, the rolled piece processed in the finish rolling stage is cooled again, so that the temperature of the steel bar material is reduced, the grain structure is kept uniform, the finally produced ribbed steel bar is stable in performance, the grain size meets the requirement, and the comprehensive mechanical performance of the ribbed steel bar is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metal hot rolling processing, and in particular relates to a method and equipment for hot rolling ribbed steel bars. Background Art

[0002] GB 1499.2-2024, "Steel for Reinforced Concrete - Part 2: Hot-rolled Ribbed Bars," allows for the microalloying of steel with elements such as vanadium, niobium, and titanium to improve strength. After years of production practice, vanadium-nitrogen alloys have become the most commonly used microalloying raw material for steel. Vanadium primarily affects steel strength by forming V(C,N) particles with carbon and nitrogen, which precipitate between grains and produce precipitation strengthening. At a vanadium-to-nitrogen stoichiometric ratio of 3.64, vanadium fully combines with nitrogen to form vanadium nitride particles, exerting its strengthening effect. Currently used vanadium-nitrogen alloys have a stoichiometric ratio of approximately 5.0. Due to insufficient nitrogen content, some vanadium fails to combine with nitrogen and thus fails to exert precipitation strengthening. This necessitates the addition of additional manganese-silicon alloys to maintain steel strength, resulting in high alloy material consumption and production costs. Some companies use nitrogen purging during smelting to increase nitrogen content in molten steel, but this has been unsatisfactory. Firstly, the nitrogen absorption rate is low and unstable, and secondly, prolonged nitrogen purging can cause the molten steel temperature to drop, making subsequent operations difficult. Therefore, it is necessary to study the method of increasing nitrogen in molten steel, give full play to the strengthening effect of vanadium, reduce the consumption of silicon-manganese alloy, provide a low-cost and moderate-performance production method for hot-rolled ribbed steel bar HRB400E, and create its due social and economic value.

[0003] In the prior art, some invention patents in the field of metal hot rolling processing technology are disclosed. Among them, the invention patent with the publication number of CN116651927B discloses a preparation device for a Cr-containing HRB400E hot-rolled ribbed steel bar product, including a workbench; a first deviation measurement unit is arranged on the workbench; a first deviation determination unit determines the first maximum deviation position and the first maximum deviation value of the pre-hot-rolled steel bar; a rough rolling mechanism is arranged on the workbench and performs the first hot rolling on the pre-hot-rolled steel bar under the first rough rolling condition; a second deviation measurement unit is arranged on the workbench to obtain the second deviation value and / or the current maximum deviation position and the current maximum deviation value of the current first maximum deviation position; a second deviation determination unit determines that the finishing rolling mechanism performs the second hot rolling on the pre-hot-rolled steel bar under the first finishing rolling condition; the finishing rolling mechanism is arranged on the workbench and determines to perform the second hot rolling on the first hot-rolled steel bar under the first finishing rolling condition, and performs two processes of rough rolling and finishing rolling on the pre-hot-rolled steel bar. The straightening effect is good and the production efficiency is improved. The distance between the intermediate rolling mill and the finishing rolling mill is designed to be relatively close, resulting in a relatively high temperature of the rolled piece entering the finishing rolling mill after intermediate rolling, a relatively large temperature difference between the surface and the core of the steel bar, and the finishing rolling stage often gives large deformations in multiple passes, resulting in a relatively high temperature rise of the rolled piece and uneven grain structure, ultimately causing the performance of the produced threaded steel bar to be unstable, the grain size not meeting the requirements of fine-grained steel bars, and the comprehensive mechanical properties being relatively poor.

[0004] Based on this, the present invention designs a hot rolling method and equipment for ribbed steel bars to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to propose a hot rolling method and equipment for ribbed steel bars to solve the problems that the distance between the intermediate rolling mill and the finishing rolling mill is designed to be relatively close, resulting in a relatively high temperature of the rolled piece entering the finishing rolling mill after intermediate rolling, a relatively large temperature difference between the surface and the core of the steel bar, and the finishing rolling stage often gives large deformations in multiple passes, resulting in a relatively high temperature rise of the rolled piece and uneven grain structure, ultimately causing the performance of the produced threaded steel bar to be unstable, the grain size not meeting the requirements of fine-grained steel bars, and the comprehensive mechanical properties being relatively poor.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A hot rolling equipment for ribbed steel bars includes a hot rolling frame. A medium rolling mill and a finishing rolling mill are respectively installed on the top of the hot rolling frame. Rolling frames are connected to the rear of the medium rolling mill and the finishing rolling mill respectively on the top of the hot rolling frame. A sleeving assembly is connected to the rolling frames. A pretreatment assembly is rotatably connected to the inner side of the sleeving assembly. The same torsion assembly is sleeved on multiple pretreatment assemblies for simultaneously driving the multiple pretreatment assemblies to rotate inside the sleeving assembly. Vibration generating assemblies are clamped in the ports of the multiple pretreatment assemblies.

[0008] As a further description of the above technical solution:

[0009] The set of components includes a plurality of clamp clips connected to the top of the rolling stand. An elastic sleeve is filled inside the clamp clips. The clamp clips are rotationally connected to a set of parts through the elastic sleeve. The set of parts includes an outer sleeve rotationally connected to the elastic sleeve. A plurality of suction holes arranged in an annular array are formed on the circumferential surface of the end of the outer sleeve. First sealing bearings are sleeved on both sides of the outer sleeve corresponding to the suction holes, and the same first adapter ring is sleeved on the two first sealing shafts;

[0010] The outer ring surface of the first adapter ring is connected to a first bridging frame. The first adapter ring is connected to the clamp clip through the first bridging frame. The same suction pipe is connected to a plurality of first adapter rings. The tail end of the suction pipe is communicated with a filter head. A machine frame is connected to the rear side of the rolling stand. A water pump is installed on the machine frame. The other end of the filter head is communicated with the input port of the water pump. A motor is installed on the machine frame. A transmission shaft for transmission is connected between the motor and the water pump.

[0011] As a further description of the above technical solution:

[0012] Filling rings are clamped inside both ports of the outer sleeve, and an annular groove is formed on the inner ring surface of the outer sleeve.

[0013] As a further description of the above technical solution:

[0014] The preprocessing component includes an inner sleeve sleeved inside one of the filling rings. A plurality of spray holes are formed on the outer ring surface of one end of the inner sleeve, and the plurality of spray holes are arranged in a spiral shape. A plurality of adjustment holes are formed on the outer ring surface of the inner sleeve;

[0015] An adjustment sleeve is rotationally connected to the inner ring surface of the outer sleeve. A plurality of adjustment parts are connected to the inner ring surface of the adjustment sleeve corresponding to the plurality of adjustment holes. The adjustment part includes an outer adapter joint connected to the inner ring surface of the adjustment sleeve. The inner side of the other end of the outer adapter joint is rotationally connected to an adjustment shaft. The other end of the adjustment shaft is rotationally connected to an inner adapter joint. The other end of the inner adapter joint is elastically connected to a vibrator acting on the ribbed steel bar;

[0016] An arc-shaped adjustment opening is formed on the outer ring surface of the outer sleeve. A threaded sleeve is inserted into the arc-shaped adjustment opening. The end of the threaded sleeve is connected to the adjustment sleeve. An adjustment bolt is threadedly connected to the other port of the threaded sleeve. An arc-shaped sealing piece is rotationally connected to the adjustment bolt. The arc-shaped sealing piece is rotationally connected to the outer ring surface of the outer sleeve and is used for sealing the arc-shaped adjustment opening.

[0017] As a further description of the above technical solution:

[0018] The torsion assembly includes a plurality of first driven gears respectively sleeved on a plurality of outer sleeves, a first driving gear is sleeved on the transmission shaft, and the first driving gear and the plurality of first driven gears are sleeved with the same first transmission gear belt.

[0019] As a further description of the above technical solution:

[0020] The vibration generating assembly comprises a vibration sleeve which is sleeved in the port of the inner sleeve, a vibration tube is rotatably connected in the vibration sleeve, and a pendulum is sleeved on the other end of the vibration tube.

[0021] As a further description of the above technical solution:

[0022] The plurality of vibration tubes are sleeved with a same second driven tooth surface wheel, the transmission shaft is sleeved with a second driving tooth surface wheel, the second driving tooth surface wheel and the plurality of second driven tooth surface wheels are sleeved with a same second transmission tooth surface belt, the plurality of vibration tubes are rotatably connected to a same support frame, and the end of the support frame is connected to a support pile connected to the top of the rolling stand.

[0023] As a further description of the above technical solution:

[0024] The outer arc surface of the other end of the outer sleeve is provided with a plurality of diversion holes in a circular array, and second sealed bearings are mounted on both sides of the corresponding diversion holes on the outer arc surface of the outer sleeve, and the same second adapter ring is mounted on the two second sealed bearings, and the second adapter ring is connected to a second bridge frame, and the second adapter ring is connected to the clamp through the second bridge frame, and the multiple second adapter rings are connected to the same drainage tube.

[0025] A method for hot rolling ribbed steel bars, comprising:

[0026] Hot metal pretreatment: The sulfur content (wt%) of hot metal transferred from the blast furnace to the converter is ≤0.05%, and the remaining elements comply with YB / T 5296-2011 "Pig Iron for Steelmaking";

[0027] Converter smelting: adopt quantitative charging system, molten iron ratio is 1:3, first add scrap steel, then add molten iron, adopt single slag method smelting, slag basicity is controlled at 2.8-3.2, lime is added in two batches, 1 / 2-2 / 3 of the total weight is added at the beginning of blowing, including an appropriate amount of light-burned dolomite, after the first batch of slag is melted, the second batch of materials is added gradually in small amounts several times, generally added over 4-6 minutes, oxygen pressure is 0.80MPa, oxygen flow rate is 27000m3 / h, and 28000m3 / h in the later stage of blowing, endpoint control adopts one-time carbon pulling method, and tapping temperature is controlled at 1630±10℃;

[0028] Deoxidizing alloying: First, add multi-element nitrogen alloy, deoxidizer, and carburizer into the ladle during tapping from the converter. The addition amount of the multi-element nitrogen alloy is 0.6 - 0.8 kg / t. When the molten steel is seen in the ladle, open the nitrogen supply valve to blow nitrogen. The gas blowing method adopts the eccentric bottom blowing method with a porous plug for gas supply, and the pressure is controlled at 0.40 - 1.20 MPa. It is appropriate to control the pressure so that the molten steel does not splash out of the ladle. Then, add ferrosilicon manganese alloy, vanadium nitride alloy, and final deoxidizer during the process of tapping to 1 / 4 - 3 / 4. The final chemical composition range is: C: 0.23% - 0.25%, Si: 0.25% - 0.35%, Mn: 1.25% - 1.40%, N: 0.012% - 0.016%, V: 0.020% - 0.025%, P: ≤0.040%, S: ≤0.040%, and the rest are residual elements;

[0029] Continuous casting: Transfer the ladle of molten steel to the casting position, open the sliding gate of the ladle. When starting casting from the tundish, the liquid level in the tundish reaches about 300 mm. Appropriately close the sliding gate of the ladle, add a covering agent to the liquid surface of the molten steel, and control the thickness of the covering agent at 15 - 20 mm. Start casting when the liquid level in the tundish reaches 400 mm. The water volume in the mold is ≮90 m³ / h·strand·h, the specific water volume of secondary cooling is 1.0 - 1.5 L / kg, the casting speed is 2.5 - 3.5 m / min, and the cross-sectional size of the billet is 165 mm × 165 mm;

[0030] Rolling: After the billet is cut at the continuous caster, it is heated in a heating furnace. The furnace temperature in the soaking section is 1180 ± 20 °C, the starting rolling temperature is 1000 ± 20 °C, no controlled rolling is carried out in the middle, the temperature entering the finishing mill is ≤1000 °C, and the temperature on the cooling bed is 900 ± 30 °C.

[0031] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are:

[0032] 1. In the present invention, the temperature of the reinforcing bar material is reduced after medium rolling, so that the temperature difference between the surface and the core of the reinforcing bar material remains consistent, and the processing in the finishing rolling stage is more stable. After the rolled piece processed in the finishing rolling stage is cooled again, the temperature of the reinforcing bar material is reduced, ensuring that the grain structure remains uniform, making the performance of the finally produced ribbed steel bars stable, the grain size meets the requirements, and improving its comprehensive mechanical properties.

[0033] 2. In the present invention, compared with the traditional use of a water cooling pool, it can avoid the leakage of smoke and irritating gases to a greater extent, avoid environmental pollution, and provide a good working environment for workers.

[0034] 3. In the present invention, when the swirl acts on the surface of the steel bar material, the iron oxide scale on the surface of the steel bar material is blown off, and at the same time, the compressed air flow squeezes out the oxygen inside the inner sleeve, and the inlet and outlet are sealed to a certain extent, reducing the contact between the steel bar material and oxygen, thereby reducing the generation of iron oxide scale. Compared with the above-mentioned existing technology, this solution facilitates the removal of iron oxide scale and reduces the generation of pitting.

[0035] 4. In the present invention, different vibration frequencies are used to move the oxide scale on the surface of the steel bar material to the side with faster vibration, thereby reducing the pressure of the cooling water rotary spray cleaning, ensuring that the heat treatment processing equipment can achieve dual and efficient removal of oxide scale waste chips on the surface of the steel bar material when hot rolling the steel bar material. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the overall structure of a ribbed steel bar hot rolling method and equipment proposed by the present invention;

[0037] Figure 2 This is a schematic structural diagram of a disassembled pretreatment component in a method and apparatus for hot rolling ribbed steel bars proposed by the present invention;

[0038] Figure 3 This is a structural schematic diagram of a pretreatment component in a method and apparatus for hot rolling ribbed steel bars proposed in the present invention from another perspective;

[0039] Figure 4 This is a structural schematic diagram of a ribbed steel bar hot rolling method and equipment proposed by the present invention from another perspective;

[0040] Figure 5 This is a schematic diagram of the structure of a ribbed steel bar hot rolling method and equipment proposed by the present invention;

[0041] Figure 6 This is a schematic structural diagram of a set of components in a method and equipment for hot rolling ribbed steel bars proposed by the present invention;

[0042] Figure 7 This is a schematic structural diagram of the disassembled components of a ribbed steel bar hot rolling method and equipment proposed by the present invention;

[0043] Figure 8 This is a structural schematic diagram of a vibration generating component in a ribbed steel bar hot rolling method and equipment proposed by the present invention.

[0044] Legend:

[0045] 1. Hot rolling stand; 2. Medium rolling mill; 3. Finish rolling mill; 4. Rolling stand; 5. Sleeve assembly; 501. Clamp; 502. Elastic sleeve; 503. Sleeve part; 5031. Outer sleeve; 5032. Suction hole; 5033. First sealed bearing; 5034. First adapter ring; 5035. First bridging frame; 504. Filler ring; 505. Suction pipe; 506. Water pump; 507. Motor; 508. Transmission shaft; 509. Filter head; 6. Pretreatment assembly; 601. Inner sleeve; 602. Injection hole; 603. Adjusting sleeve; 604. Adjusting part; 6041. Outer adapter; 6042. Inner adapter; 6043. Adjusting shaft; 6044. Vibrator; 605. Arc-shaped sealing piece; 606. Threaded sleeve; 607. Adjusting bolt; 7. Torsion assembly; 701. First driven gear face wheel; 702. First driving gear face wheel; 703. First driving gear belt; 8. Vibration generating assembly; 801. Vibration pipe; 802. Pendulum; 803. Second driven gear face wheel; 804. Second driving gear belt; 805. Second driving gear face wheel; 806. Support frame; 807. Support pile; 9. Second adapter ring; 10. Second sealed bearing. Detailed implementation manners

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0047] Please refer to the attached Figure 1 - attached Figure 8 The present invention provides a technical solution: a ribbed steel bar hot rolling device, including a hot rolling stand 1, a medium rolling mill 2 and a finish rolling mill 3 are respectively installed on the top of the hot rolling stand 1, rolling stands 4 are connected to the rear of the medium rolling mill 2 and the finish rolling mill 3 correspondingly on the top of the hot rolling stand 1, a sleeve assembly 5 is connected to the rolling stand 4, a pretreatment assembly 6 is rotatably connected to the inner side of the sleeve assembly 5, the same torsion assembly 7 is sleeved on a plurality of pretreatment assemblies 6 for simultaneously driving the plurality of pretreatment assemblies 6 to rotate inside the sleeve assembly 5, and a vibration generating assembly 8 is clamped in the ports of the plurality of pretreatment assemblies 6.

[0048] Preferably, the set assembly 5 includes a plurality of clamp clips 501 connected to the top of the rolling stand 4. An elastic sleeve 502 is filled inside the clamp clip 501. The clamp clip 501 is rotationally connected to a set piece 503 through the elastic sleeve 502. The set piece 503 includes an outer sleeve 5031 rotationally connected to the elastic sleeve 502. A plurality of suction holes 5032 arranged in an annular array are formed on the circumferential surface of the end of the outer sleeve 5031. First sealing bearings 5033 are sleeved on both sides of the outer sleeve 5031 corresponding to the suction holes 5032. The same first transfer ring 5034 is sleeved on the two first sealing shafts.

[0049] A first bridging frame 5035 is connected to the outer ring surface of the first transfer ring 5034. The first transfer ring 5034 is connected to the clamp clip 501 through the first bridging frame 5035. The same suction pipe 505 is connected to a plurality of first transfer rings 5034. The tail end of the suction pipe 505 is communicated with a filter head 509. A machine frame is connected to the rear side of the rolling stand 4. A water pump 506 is installed on the machine frame. The other end of the filter head 509 is communicated with the input port of the water pump 506. A motor 507 is installed on the machine frame. A transmission shaft 508 for transmission is connected between the motor 507 and the water pump 506.

[0050] Preferably, packing rings 504 are clamped inside both ports of the outer sleeve 5031. An annular groove is formed on the inner ring surface of the outer sleeve 5031.

[0051] Preferably, the pretreatment assembly 6 includes an inner sleeve 601 sleeved inside one of the packing rings 504. A plurality of spray holes 602 are formed on the outer ring surface of one end of the inner sleeve 601. The plurality of spray holes 602 are arranged in a spiral shape. A plurality of adjustment holes are formed on the outer ring surface of the inner sleeve 601.

[0052] An adjustment sleeve 603 is rotationally connected to the inner ring surface of the outer sleeve 5031. A plurality of adjustment members 604 are connected to the inner ring surface of the adjustment sleeve 603 corresponding to the plurality of adjustment holes. The adjustment member 604 includes an outer side adapter 6041 connected to the inner ring surface of the adjustment sleeve 603. The inner side of the other end of the outer side adapter 6041 is rotationally connected to an adjustment shaft 6043. The other end of the adjustment shaft 6043 is rotationally connected to an inner side adapter 6042. The other end of the inner side adapter 6042 is elastically connected to a vibrator 6044 acting on the ribbed steel bar.

[0053] An arc-shaped adjustment opening is formed on the outer ring surface of the outer sleeve 5031. A threaded sleeve 606 is inserted into the arc-shaped adjustment opening. The end of the threaded sleeve 606 is connected to the adjustment sleeve 603. An adjustment bolt 607 is threadedly connected to the other port of the threaded sleeve 606. An arc-shaped sealing piece 605 is rotationally connected to the adjustment bolt 607. The arc-shaped sealing piece 605 is rotationally connected to the outer ring surface of the outer sleeve 5031 and is used to block the arc-shaped adjustment opening.

[0054] Preferably, the torsion assembly 7 includes a plurality of first driven bevel gears 701 respectively sleeved on a plurality of outer sleeves 5031. A first driving bevel gear 702 is sleeved on the transmission shaft 508. The first driving bevel gear 702 and the plurality of first driven bevel gears 701 are sleeved with the same first transmission belt 703.

[0055] Preferably, the vibration generating assembly 8 includes a vibration sleeve sleeved inside the port of the inner sleeve 601. A vibration tube 801 is rotatably connected inside the vibration sleeve. The other end of the vibration tube 801 is sleeved with a pendulum 802.

[0056] Preferably, a plurality of second driven bevel gears 803 are sleeved on the plurality of vibration tubes 801. A second driving bevel gear 805 is sleeved on the transmission shaft 508. The second driving bevel gear 805 and the plurality of second driven bevel gears 803 are sleeved with the same second transmission belt 804. A same support frame 806 is rotatably connected to the plurality of vibration tubes 801. The end of the support frame 806 is connected with a support pile 807 connected to the top of the rolling stand 4.

[0057] Preferably, a plurality of diversion holes arranged in an annular array are formed on the outer arc surface at the other end of the outer sleeve 5031. Second sealing bearings 10 are sleeved on both sides of the outer arc surface of the outer sleeve 5031 corresponding to the diversion holes. A same second adapter ring 9 is sleeved on the two second sealing bearings 10. A second bridging frame is connected to the second adapter ring 9. The second adapter ring 9 is connected to the clamp 501 through the second bridging frame. A same drainage pipe is communicated with the plurality of second adapter rings 9.

[0058] A method for hot rolling ribbed steel bars, the method for hot rolling ribbed steel bars includes:

[0059] Hot metal pretreatment: The content of S element in the hot metal transferred from the blast furnace to the converter is wt% ≤ 0.05%, and the other elements comply with YB / T5296-2011 "Pig Iron for Steelmaking";

[0060] Converter smelting: Adopt a quantitative charging system, the hot metal ratio is 1:3. First, add scrap steel, and then add hot metal. Adopt the single slag method for smelting. Control the slag basicity at 2.8 - 3.2. Add lime in two batches. When starting to blow, add 1 / 2 - 2 / 3 of the total weight first, including an appropriate amount of light burned dolomite. After the first batch of slag materials are melted, add the second batch of materials gradually in multiple small amounts, generally adding them within 4 - 6 minutes. The oxygen pressure is 0.80MPa, the oxygen flow rate is 27000m3 / h, and the oxygen flow rate in the later stage of blowing is 28000m3 / h. The end point control adopts the one-time carbon-pulling method, and the tapping temperature is controlled at 1630 ± 10°C;

[0061] Deoxidation and alloying: Multi-element nitrogen alloy, deoxidizer and recarburizer are first added to the converter ladle. The amount of multi-element nitrogen alloy added is 0.6-0.8kg / t. When molten steel appears in the ladle, the nitrogen supply valve is opened for nitrogen blowing. The blowing method adopts eccentric bottom blowing with air-permeable bricks. The pressure is controlled at 0.40-1.20MPa. It is best to control the pressure so that the molten steel does not splash out of the ladle. Then, silicon-manganese alloy, vanadium-nitrogen alloy and final deoxidizer are added during the process of tapping 1 / 4 to 3 / 4. The final chemical composition range is: C: 0.23%-0.25%, Si: 0.25%-0.35%, Mn: 1.25%-1.40%, N: 0.012%-0.016%, V: 0.020%-0.025%, P: ≤0.040%, S: ≤0.040%, and the rest are residual elements.

[0062] Continuous casting: Turn the molten steel ladle to the pouring position, open the ladle sliding nozzle, and when the ladle starts pouring, the liquid level in the tundish should reach about 300mm. Appropriately close the ladle sliding nozzle, add covering agent to the molten steel surface, and control the thickness of the covering agent to 15-20mm. When the tundish liquid level reaches 400mm, pouring should start. The water volume of the crystallizer should be ≥90m3 / h·flow hour, the secondary cooling water ratio should be 1.0-1.5L / kg, the casting speed should be 2.5-3.5m / min, and the cross-sectional size of the billet should be 165mm×165mm.

[0063] Rolling: After the billet is cut at the continuous casting machine, it is heated in a heating furnace with the temperature of the soaking section at 1180±20℃ and the starting rolling temperature at 1000±20℃. No controlled rolling is performed in the middle. The temperature entering the finishing mill 3 is ≤1000℃ and the temperature of the upper cooling bed is 900±30℃.

[0064] Working principle, when using:

[0065] After high-temperature heating, the steel bar material is sequentially subjected to three hot rolling processes: rough rolling, intermediate rolling, and finish rolling. The intermediate rolling and finish rolling are respectively completed by the intermediate rolling mill 2 and the finish rolling mill 3. After the intermediate rolling and finish rolling, the steel bar material is cooled and surface treated.

[0066] During the hot rolling process of the steel bar material, after entering the outer sleeve 5031, it passes through the inner sleeve 601 and the vibration tube 801 in sequence, controls the operation of the motor 507, and the output shaft of the motor 507 drives the water pump 506 to work through the transmission shaft 508. During the rapid rotation process, the transmission shaft 508 uses the first active tooth surface wheel 702, the first transmission tooth surface belt 703 and the multiple first driven tooth surface wheels 701 to simultaneously drive the multiple outer sleeves 5031 to rotate. In this process, the cooling water of the steel bar material is introduced into the inner side of the second adapter ring 9 through the drainage pipe. The cooling water flows into the annular groove opened on the inner ring surface of the outer sleeve 5031 through multiple diversion holes, and then passes through The multiple spray holes 602 spray water onto the steel bar material. Since the inner sleeve is in a rotating state and the multiple spray holes 602 are arranged in a spiral shape, the cooling water sprayed through the multiple spray holes 602 will generate a swirl flow, and the swirl flow direction is opposite to the transmission direction of the steel bar material. The steel bar material is cooled after the intermediate rolling, so that the temperature difference between the surface and the core of the steel bar material is kept consistent, and the processing in the finishing rolling stage is more stable. The ribbed steel bar processed in the finishing rolling stage is cooled again to reduce the temperature of the steel bar material, ensuring that the grain structure remains uniform, so that the performance of the ribbed steel bar finally produced is stable, the grain size meets the requirements, and its comprehensive mechanical properties are improved.

[0067] The vortex flows inside the regulating sleeve 603 toward the suction hole 5032. The water pump 506 simultaneously extracts the cooling water in the outer sleeve 5031 through the suction pipe 505. When the cooling water cools the steel bar material, smoke and irritating gases are generated. At the same time, the cooling water also carries metal slag that falls off the surface of the steel bar material. The smoke, irritating gases and metal slag are filtered and adsorbed by the filter head 509 and then discharged by the water pump 506 for secondary use. Compared with the traditional use of a water cooling pool, the leakage of smoke and irritating gases can be avoided to a greater extent, thus avoiding environmental pollution and providing a good working environment for workers.

[0068] When the swirl acts on the surface of the steel bar, the iron oxide scale on the surface of the steel bar is blown off. At the same time, the compressed airflow squeezes out the oxygen inside the inner sleeve 601, sealing the inlet and outlet to a certain extent, reducing the contact between the steel bar and oxygen, thereby reducing the generation of iron oxide scale. Compared with the above-mentioned existing technologies, this solution facilitates the removal of iron oxide scale and reduces the generation of pitting.

[0069] The transmission shaft 508 also drives a plurality of vibration tubes 801 simultaneously through a transmission system composed of a second driving tooth surface wheel 805, a second transmission tooth belt 804, and a plurality of second driven tooth surface wheels 803. The vibration tubes 801 drive the pendulums 802 to rotate rapidly and generate vibrations. The vibrations act on the surface of the steel bar material through the vibrators 6044, and the scale on the surface of the steel bar material is moved to the side with faster vibrations through different vibration frequencies, reducing the pressure of the rotating spray cleaning with cooling water, ensuring that the heat treatment processing equipment can achieve dual and efficient removal of the scale waste on the surface of the steel bar material during the hot rolling processing of the steel bar material;

[0070] Loosen the adjusting bolt 607, and move the arc-shaped sealing piece 605 to drive the threaded sleeve 606. The threaded sleeve 606 drives the adjusting sleeve 603 to rotate. During the rotation of the adjusting sleeve 603, it will simultaneously drive a plurality of outer adapter sleeves to move relative to the corresponding inner adapters 6042. The outer adapter 6041 generates a thrust or a pull force on the inner adapter 6042 through the adjusting shaft 6043, so that a plurality of vibrators 6044 can be brought closer to or away from each other, and thus can be adaptively adjusted according to the model of the steel bar material, with high flexibility and strong practicability.

[0071] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A hot rolling equipment for ribbed steel bars, comprising a hot rolling frame (1), a medium rolling mill (2) and a finishing mill (3) are respectively installed at the top of the hot rolling frame (), rolling frames (4) are connected to the rear of the medium rolling mill (2) and the finishing mill (3) correspondingly at the top of the hot rolling frame (1), and it is characterized in that, A set of components (5) is connected to the rolling stand (4). A pretreatment component (6) is rotatably connected to the inner side of the set of components (5). A torsion component (7) is sleeved on a plurality of the pretreatment components (6) and is used to simultaneously drive the plurality of pretreatment components (6) to rotate inside the set of components (5). A vibration generating component (8) is clamped in the ports of the plurality of pretreatment components (6).

2. The hot rolling equipment for ribbed steel bars according to claim 1, characterized in that, The set of components (5) includes a plurality of clamp clips (501) connected to the top of the rolling stand (4). An elastic sleeve (502) is filled inside the clamp clip (501). The clamp clip (501) is rotatably connected to a sleeve part (503) through the elastic sleeve (502). The sleeve part (503) includes an outer sleeve (5031) rotatably connected to the elastic sleeve (502). A plurality of suction holes (5032) arranged in an annular array are formed on the circumferential surface at the end of the outer sleeve (5031). A first sealing bearing (5033) is sleeved on both sides of the outer sleeve (5031) corresponding to the suction holes (5032). The same first adapter ring (5034) is sleeved on the two first sealing shafts. A first bridging frame (5035) is connected to the outer ring surface of the first adapter ring (5034). The first adapter ring (5034) is connected to the clamp clip (501) through the first bridging frame (5035). The same suction pipe (505) is connected to a plurality of the first adapter rings (5034). The tail end of the suction pipe (505) is communicated with a filter head (509). A machine frame is connected to the rear side of the rolling stand (4). A water pump (506) is installed on the machine frame. The other end of the filter head (509) is communicated with the input port of the water pump (506). A motor (507) is installed on the machine frame. A transmission shaft (508) for transmission is connected between the motor (507) and the water pump (506).

3. The hot rolling equipment for ribbed steel bars according to claim 2, characterized in that, Packing rings (504) are clamped in both ports of the outer sleeve (5031). An annular groove is formed on the inner ring surface of the outer sleeve (5031).

4. The hot rolling equipment for ribbed steel bars according to claim 3, characterized in that, The pretreatment component (6) includes an inner sleeve (601) sleeved in one of the packing rings (504). A plurality of injection holes (602) are formed on the outer ring surface of one end of the inner sleeve (601). The plurality of injection holes (602) are arranged in a spiral shape. A plurality of adjustment holes are formed on the outer ring surface of the inner sleeve (601). An adjustment sleeve (603) is rotatably connected to the inner ring surface of the outer sleeve (5031). A plurality of adjustment members (604) are connected to the inner ring surface of the adjustment sleeve (603) corresponding to the plurality of adjustment holes. The adjustment member (604) includes an outer side adapter (6041) connected to the inner ring surface of the adjustment sleeve (603). The inner side of the other end of the outer side adapter (6041) is rotatably connected to an adjustment shaft (6043). The other end of the adjustment shaft (6043) is rotatably connected to an inner side adapter (6042). The other end of the inner side adapter (6042) is elastically connected to an oscillator (6044) acting on ribbed steel bars. The outer ring surface of the outer sleeve (5031) is provided with an arc-shaped adjustment opening, a threaded sleeve (606) is inserted into the arc-shaped adjustment opening, the end of the threaded sleeve (606) is connected to an adjustment sleeve (603), a regulating bolt (607) is threadedly connected to the other port of the threaded sleeve (606), an arc-shaped sealing piece (605) is rotatably connected to the regulating bolt (607), and the arc-shaped sealing piece (605) is rotatably connected to the outer ring surface of the outer sleeve (5031) and is used for plugging the arc-shaped adjustment opening.

5. The hot rolling equipment for ribbed steel bars according to claim 4, characterized in that, The torsion assembly (7) includes a plurality of first driven bevel gears (701) respectively sleeved on a plurality of outer sleeves (5031), a first driving bevel gear (702) is sleeved on the transmission shaft (508), and the first driving bevel gear (702) and the plurality of first driven bevel gears (701) are sleeved with the same first transmission belt (703).

6. The hot rolling equipment for ribbed steel bars according to claim 5, characterized in that, The vibration generating assembly (8) includes a vibration sleeve sleeved in the port of the inner sleeve (601), a vibration pipe (801) is rotatably connected in the vibration sleeve, and a pendulum (802) is sleeved at the other end of the vibration pipe (801).

7. The hot rolling equipment for ribbed steel bars according to claim 6, characterized in that, The same second driven bevel gear (803) is sleeved on a plurality of the vibration pipes (801), a second driving bevel gear (805) is sleeved on the transmission shaft (508), the second driving bevel gear (805) and the plurality of second driven bevel gears (803) are sleeved with the same second transmission belt (804), the same support frame (806) is rotatably connected to the plurality of vibration pipes (801), and the end of the support frame (806) is connected to a support pile (807) connected to the top of the rolling stand (4).

8. A ribbed steel bar hot rolling device according to claim 7, characterized in that, A plurality of diversion holes in an annular array are provided on the outer arc surface at the other end of the outer sleeve (5031), second sealing bearings (10) are sleeved on both sides of the outer arc surface of the outer sleeve (5031) corresponding to the diversion holes, the same second adapter ring (9) is sleeved on the two second sealing bearings (10), a second bridging frame is connected to the second adapter ring (9), the second adapter ring (9) is connected to the clamp (501) through the second bridging frame, and the same drainage pipe is communicated with the plurality of second adapter rings (9).

9. A hot rolling method for ribbed steel bars, according to the hot rolling equipment for ribbed steel bars described in any one of claims 1-8, characterized in that, The method for hot rolling ribbed steel bars includes: Hot metal pretreatment: The content of S element (wt%) in the hot metal transferred from the blast furnace to the converter is ≤ 0.05%, and the other elements meet YB / T 5296-2011 "Pig Iron for Steelmaking". Converter smelting: The quantitative charging system is adopted, the hot metal ratio is 1:3, scrap steel is added first, and then hot metal is added. The single slag method is used for smelting, the slag basicity is controlled at 2.8 - 3.2, lime is added in two batches. When starting to blow, 1 / 2 - 2 / 3 of the total weight is added first, including an appropriate amount of light burned dolomite. After the first batch of slag materials are melted, the second batch of materials is added gradually in multiple small amounts, generally added within 4 - 6 minutes. The oxygen pressure is 0.80 MPa, the oxygen flow rate is 27000 m3 / h, and the oxygen flow rate in the later stage of blowing is 28000 m3 / h. The end point control adopts the one-time carbon drawing method, and the tapping temperature is controlled at 1630 ± 10 °C. Deoxidizing alloying: First, add multi-element nitrogen alloy, deoxidizer and carburizer into the ladle when tapping steel from the converter. The addition amount of multi-element nitrogen alloy is 0.6 - 0.8 kg / t. Open the nitrogen supply valve to blow nitrogen as soon as the molten steel is seen in the ladle. The gas blowing method adopts the eccentric bottom blowing method with a porous plug for gas supply, and the pressure is controlled at 0.40 - 1.20 MPa. It is appropriate to control the pressure so that the molten steel does not splash out of the ladle. Then, add ferrosilicon manganese alloy, vanadium nitride alloy and final deoxidizer during the process of tapping steel to 1 / 4 - 3 / 4. The final chemical composition range is: C: 0.23% - 0.25%, Si: 0.25% - 0.35%, Mn: 1.25% - 1.40%, N: 0.012% - 0.016%, V: 0.020% - 0.025%, P: ≤0.040%, S: ≤0.040%, and the rest are residual elements; Continuous casting: Transfer the ladle of molten steel to the casting position, open the sliding gate of the ladle. When starting casting in the tundish, the liquid level in the tundish reaches about 300 mm. Appropriately close the sliding gate of the ladle, and add a covering agent to the liquid surface of the molten steel. The thickness of the covering agent is controlled at 15 - 20 mm. Start casting when the liquid level in the tundish reaches 400 mm. The water volume in the mold is ≮90 m3 / h·strand, the secondary cooling water ratio is 1.0 - 1.5 L / kg, the casting speed is 2.5 - 3.5 m / min, and the cross-sectional size of the billet is 165 mm × 165 mm; Rolling: After the billet is cut at the continuous caster, it is heated in a heating furnace. The furnace temperature in the soaking section is 1180 ± 20 °C, the starting rolling temperature is 1000 ± 20 °C, controlled rolling is not carried out in the middle, the temperature entering the finishing mill (3) is ≤1000 °C, and the temperature on the cooling bed is 900 ± 30 °C.

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