Portable protective pouring device for continuous casting steel pouring operation and protective pouring method

Abstract

The invention relates to a portable protective pouring device for continuous casting steel pouring operation and a protective pouring method, and belongs to the technical field of continuous casting steel pouring equipment in the metallurgical industry. According to the technical scheme, a protective shell (1) is formed by combining two semicircular shell bodies, one ends of the two semicircular shell bodies are rotationally connected together, the other ends of the two semicircular shell bodies are provided with grips (7), and the grips (7) are connected together through a U-shaped lock (8); the protective shell (1) is provided with nozzle holes (10) matched with a tundish upper nozzle (13) and a submerged tundish lower nozzle (14), an annular blowing pipeline (3) is arranged in the protective shell (1), a protective gas pipeline connector (2) is arranged on the annular blowing pipeline (3), and a plurality of blowing holes (4) are formed in the circumferential direction of the annular blowing pipeline (3). The tundish nozzle sealing device has the beneficial effects that in the continuous casting steel pouring operation, secondary oxidation and nitrogen increase of molten steel caused by insufficient sealing of the tundish nozzle connecting position can be avoided, and the product quality is guaranteed.

Description

Technical Field

[0001] The invention relates to a portable protective pouring device and a protective pouring method for continuous casting and steel pouring operations, belonging to the technical field of continuous casting and steel pouring equipment in the metallurgical industry. Background Art

[0002] The secondary oxidation and nitrogen addition of molten steel in continuous casting are the main reasons for the reduction of ingot quality. The mechanism is as follows: due to the flow of molten steel, negative pressure is generated inside the nozzle, and air is affected by atmospheric pressure and enters the nozzle from the nozzle connection. The main components of air are N2 (78%) and O2 (21%). Dissolution and oxidation cause the above-mentioned oxidation and nitrogen addition of molten steel. Protective pouring is an effective means of improving the quality of continuous casting ingots. Inert gas argon is usually used as the main means of protective pouring. An argon atmosphere is created at the nozzle connection to prevent air from entering the nozzle. However, due to the influence of equipment, most of the connections between the upper nozzle of the tundish and the lower nozzle of the submerged tundish have no protective pouring measures, and it is impossible to smelt the graded steel or the quality of the cast ingot does not meet the requirements, which restricts the development of clean steel in enterprises to a certain extent. Summary of the invention

[0003] The purpose of the present invention is to provide a portable protective pouring device and a protective pouring method for continuous casting and steel pouring operations. In the continuous casting and steel pouring operations, the secondary oxidation and nitrogen addition of molten steel caused by insufficient sealing at the water inlet connection of the tundish can be avoided, the product quality can be ensured, and the problems existing in the background technology can be solved.

[0004] The technical solution of the present invention is: A portable protective pouring device for continuous casting and steel pouring operations comprises a protective shell, a protective gas pipeline joint, an annular blowing pipeline, blowing holes, a rotating shaft, a handle and a U-shaped lock, wherein the protective shell is composed of two semicircular shells, one end of the two semicircular shells are rotatably connected together by a rotating shaft, the other ends of the two semicircular shells are provided with handles, and the handles of the two semicircular shells are connected together by a U-shaped lock; a nozzle hole is provided on the protective shell to match the upper water inlet of the tundish and the lower water inlet of the immersed tundish, an annular blowing pipeline is provided inside the protective shell to match the connection between the upper water inlet of the tundish and the lower water inlet of the immersed tundish, a protective gas pipeline joint is provided on the annular blowing pipeline, and a plurality of blowing holes are provided in the circumferential direction of the annular blowing pipeline.

[0005] The diameter of the blowing holes in the circumferential direction of the annular blowing pipeline is 2-3 mm, and the spacing between the blowing holes is 10-20 mm.

[0006] The U-shaped lock is a U-shaped structure formed by bending a steel bar.

[0007] The handles of the two semicircular shells are provided with grooves matched with the U-shaped locks.

[0008] The protective shell is provided with a connecting chain connected with the U-shaped lock.

[0009] The protective shell is provided with a connecting slot.

[0010] A portable protective pouring method for continuous casting and steel pouring operation adopts the portable protective pouring device for continuous casting and steel pouring operation defined above and is operated according to the following steps: a. Hold the two handles of the protective shell and fix the protective shell under the steel shell at the bottom of the ladle, so that the protective shell covers the connection between the upper water inlet of the tundish and the lower water inlet of the immersion tundish, and the annular air blowing pipeline is higher than the connection between the upper water inlet of the tundish and the lower water inlet of the immersion tundish; b. Connect the protective gas pipeline joint to the argon gas source and adjust the argon gas flow rate. At this time, the argon gas enters the protective shell through the protective gas pipeline joint, the annular blowing pipeline and the blowing hole, forming an argon atmosphere at the connection between the upper water inlet of the tundish and the lower water inlet of the immersed tundish, so that the steel pouring process is in a protective state.

[0011] In the step a, the positional relationship between the blowing holes in the circumferential direction of the annular blowing pipeline and the connection between the upper water inlet of the tundish and the lower water inlet of the submerged tundish is: a horizontal spacing of 30-80 mm and a vertical spacing of 10-30 mm.

[0012] The beneficial effects of the present invention are as follows: the present invention can install the device at the bottom water outlet of the tundish as needed according to the requirements of the type of steel to be smelted, and connect the argon gas pipeline, so that steel pouring operations can be performed under the protection of inert gas, thereby avoiding air from entering the inside of the water outlet due to the negative pressure at the water outlet connection, thereby ensuring the quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the use state of the present invention; Figure 2 for Figure 1 A partial enlarged view of Figure 3 It is the front view of the present invention; Figure 4 A top view of the present invention; Figure 5 It is the AA cross-sectional view of the present invention; Figure 6 It is the BB cross-sectional view of the present invention; Figure 7 The main view of the present invention is unfolded; Figure 8 It is the CC section view; Fig. 9 Schematic diagram of the connection chain of the present invention Fig.10 This is a schematic diagram of the U-shaped lock; In the figure: protective shell 1, protective gas pipeline joint 2, annular blowing pipeline 3, blowing hole 4, connecting slot 5, rotating shaft 6, handle 7, U-shaped lock 8, connecting chain 9, water inlet hole 10, base slot 11, ladle bottom steel shell 12, tundish upper water inlet 13, immersed tundish lower water inlet 14, tundish water inlet seat brick 15, stopper rod 16, molten steel 17. DETAILED DESCRIPTION

[0014] The present invention will be further described below by way of examples with reference to the accompanying drawings.

[0015] See attached Figure 1-10 A portable protective pouring device for continuous casting and steel pouring operation, comprising a protective shell 1, a protective gas pipeline joint 2, an annular blowing pipeline 3, a blowing hole 4, a rotating shaft 6, a handle 7 and a U-shaped lock 8. The protective shell 1 is composed of two semicircular shells, one end of the two semicircular shells are rotatably connected together through a rotating shaft 6, and the other ends of the two semicircular shells are each provided with a handle 7, and the handles 7 of the two semicircular shells are connected together through a U-shaped lock 8; a nozzle hole 10 is provided on the protective shell 1 to match the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersed tundish, an annular blowing pipeline 3 is provided inside the protective shell 1 to match the connection between the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersed tundish, a protective gas pipeline joint 2 is provided on the annular blowing pipeline 3, and a plurality of blowing holes 4 are provided in the circumferential direction of the annular blowing pipeline 3.

[0016] In this embodiment, refer to the attached Figure 1-10 The present invention is divided into a blowing part, a protective shell part, a fixing part and a locking part. The blowing part includes a protective gas pipeline joint 2, an annular blowing pipeline 3 and a blowing hole 4; the protective shell part includes a protective shell 1, a rotating shaft 6 and a nozzle hole 10; the fixing part includes a connecting slot 5 and a base slot 11; the locking part includes a handle 7, a U-shaped lock 8 and a connecting chain 9.

[0017] Figure 1 , 2, 3, 4, 6, and 7 show that the protective shell 1 is two semi-cylindrical structures, which are connected by a rotating shaft 6 located at the busbar position at the apex of the semicircle and fixed into an openable cylindrical protective shell; an annular air blowing pipeline 3 is welded inside the protective shell 1, and the annular air blowing pipeline 3 is evenly divided into two sections, which are respectively located inside the two semi-cylindrical protective shells 1; holes are evenly opened on the inner side of the annular air blowing pipeline 3 as blowing holes 4, and a protective gas pipeline connector 2 is provided on the outer side of the annular air blowing pipeline 3 to pass through the protective shell 1 for connecting the gas source; water inlet holes 10 are opened at the center positions of the top and bottom of the protective shell 1 respectively; there are two sections of semi-annular connecting grooves 5 on the top of the protective shell 1, corresponding to the base grooves 11 of the bottom steel shell 12 of the middle bag; two handles 7 are symmetrically welded on the busbar on the opposite side of the rotating shaft 6; a connecting chain 9 is welded on the right side of the two handles 7, and the other end of the connecting chain 9 is connected to a U-shaped lock 8; Figure 2 , 5 It is shown that the two sections of the annular air blowing pipeline 3 are on the same plane, and when the two semi-cylindrical protective shells 1 are closed, the cross sections of the two sections of the annular air blowing pipeline 3 just touch each other; Figure 2 , 5 It is shown that the shielding gas pipeline connector 2 passes through the protective shell 1 from the left side at a 90° position, and the shielding gas pipeline connector 2 and the protective shell 1 are fully welded and sealed; Figure 2 , 5 6 shows that the inner side of the annular blowing pipeline 3 is evenly opened as the blowing holes 4, the diameter of the blowing holes is 2-3mm, and the center distance of the blowing holes is 10-20mm; Figure 2 , 4 It is shown that water inlet holes 10 are respectively opened at the top and bottom center positions of the protective shell 1, the diameter of the top water inlet hole 10 is 4mm-6mm larger than the diameter of the upper water inlet 13 of the tundish, and the diameter of the bottom water inlet hole 10 is 4mm-6mm larger than the diameter of the lower water inlet 14 of the submerged tundish; Figure 2 , 6 7 shows that the connection slot 5 at the top of the protective shell 1 is used to connect to the base slot 11 of the bottom steel shell 12 of the tundish. When the protective shell 1 is closed, the protective shell 1 can be fixed on the bottom steel shell 12. At this time, the tundish upper water inlet 13 and the immersion tundish lower water inlet 14 pass through the water inlet holes 10 at the top and bottom of the protective shell 1. Figure 3 , 4 , 8, and 10 show that there are symmetrically arranged grooves on the outer sides of the two handles 7. When the protective shell is closed, the U-shaped lock 8 is placed on the grooves on the outer sides of the two handles 7 to lock the protective shell 1 to prevent accidental opening; Figure 1 , 2It is shown that the centers of the connection slot 5, the base slot 11, the tundish upper water inlet 13, the immersion tundish lower water inlet 14, and the protective shell 1 are collinear. By adjusting the height of the base slot 11, the connection between the tundish upper water inlet 13 and the immersion tundish lower water inlet 14 is controlled to be located at about 2 / 3 of the height inside the protective shell 1; Figure 3 , 10 It is shown that the U-shaped lock 8 is obtained by bending a rectangular steel bar until the two sides are parallel, and the distance between the two sides of the U-shaped lock 8 is consistent with the distance between the grooves of the two handles 7 after the protective shell 1 is closed; Figure 2 It shows that the diameter of the annular air blowing pipeline 3 is 25-50mm, the annular air blowing pipeline 3 is slightly higher than the connection between the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersed tundish, the position relationship between the air blowing hole 4 and the connection between the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersed tundish is 30-80mm horizontally and 10-30mm vertically, the height of the protective shell 1 is 200-300mm, the diameter is determined according to the size of the lower water inlet 14 of the immersed tundish, and the wall thickness of the protective shell 1 is 3-6mm.

[0018] Figure 2 , 3 , 7, 8 show that the method of using the present invention is as follows: After installing the lower water inlet 14 of the immersion tundish to the lower end of the upper water inlet 13 of the tundish and fixing it, take down the U-shaped lock 8 in the device, hold the handle 7, open the protective shell 1 of the device, move to the water inlet position of the bottom steel shell 12 of the tundish, and after adjusting the position, align the connecting slot 5 with the base slot 11, close the protective shell 1 of the device, cover the connection between the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersion tundish, and then install the U-shaped lock 8 to the groove position of the handheld handle 7 to lock the device.

[0019] Connect the shielding gas pipeline joint 2 to the argon gas source and adjust the argon flow rate. At this time, the argon gas enters the protective shell 1 through the shielding gas pipeline joint 2, the annular blowing pipeline 3 and the blowing hole 4, and forms an argon atmosphere at the connection between the upper water inlet 13 of the tundish and the lower water inlet 14 of the immersed tundish, so that the steel pouring process is in a protective state, avoiding the secondary oxidation of the molten steel 17.

[0020] When the submerged tundish water outlet 14 is replaced or the pouring operation is finished, the device needs to be disassembled and the above process can be performed in reverse.

[0021] The present invention has a simple structure and is convenient to install and disassemble at any time according to the process requirements of steel grades, thereby making up for the production capacity of old equipment and avoiding secondary oxidation and nitrogen addition of molten steel caused by insufficient sealing at the water inlet connection of the tundish during continuous casting and steel pouring operations, thereby ensuring product quality.

[0022] An embodiment of the present invention is as follows: The outer diameter of the submerged tundish outlet 14 is 200 mm, the maximum outer diameter at the bell mouth is 314 mm, and the bell mouth height is 115 mm; The outer diameter of the tundish upper water inlet 13 is 200 mm. After the submerged tundish lower water inlet 14 is installed to the tundish upper water inlet 13, the distance between the bell mouth plane and the bottom steel shell of the tundish is 98 mm. The upper and lower bottom diameters of the protective shell 1 are 465 mm, the height is 214 mm, and the wall thickness is 5 mm; the upper and lower water inlet holes have a diameter of 205 mm; The position relationship between the blowing hole 4 and the connection between the tundish upper water inlet 13 and the submerged tundish lower water inlet 14 is 74.6 mm horizontally and 26.6 mm vertically; the diameter of the annular blowing pipeline 3 is 50 mm, the diameter of the blowing hole 4 is 3 mm, and the center distance of the blowing hole 4 is 15 mm; The connection slot 5 is 20 mm high, the base slot 11 is 21.4 mm high, and both are 7 mm thick.

[0023] The length of the grip 7 is 140 mm, the height is 40 mm, and the thickness is 23 mm; after the two grips are combined, the gap between them is 8.4 mm, and the groove spacing is 42 mm.

Claims

1. A portable protective pouring device for continuous casting and steel pouring operation, characterized in that: The invention comprises a protective shell (1), a protective gas pipeline joint (2), an annular air blowing pipeline (3), an air blowing hole (4), a rotating shaft (6), a handle (7) and a U-shaped lock (8). The protective shell (1) is composed of two semicircular shells, one end of the two semicircular shells are rotatably connected together through the rotating shaft (6), the other end of the two semicircular shells are provided with a handle (7), and the handles (7) of the two semicircular shells are connected together through the U-shaped lock (8); the protective shell (1) is provided with a nozzle hole (10) matched with a tundish upper water inlet (13) and an immersion tundish lower water inlet (14), the protective shell (1) is provided with an annular air blowing pipeline (3) matched with the connection between the tundish upper water inlet (13) and the immersion tundish lower water inlet (14), the annular air blowing pipeline (3) is provided with a protective gas pipeline joint (2), and the annular air blowing pipeline (3) is provided with a plurality of air blowing holes (4) in the circumferential direction.

2. A portable protective pouring device for continuous casting and steel pouring according to claim 1, characterized in that: The diameter of the blowing holes (4) in the circumferential direction of the annular blowing pipeline (3) is 2-3 mm, and the spacing between the blowing holes (4) is 10-20 mm.

3. The portable protective pouring device for continuous casting and steel pouring according to claim 1, characterized in that: The U-shaped lock (8) is a U-shaped structure formed by bending a steel bar.

4. A portable protective pouring device for continuous casting and steel pouring according to claim 3, characterized in that: The handles (7) of the two semicircular shells are provided with grooves matching with the U-shaped locks (8).

5. A portable protective pouring device for continuous casting and steel pouring according to claim 1 or 3, characterized in that: The protective shell (1) is provided with a connecting chain (9) connected to the U-shaped lock (8).

6. The portable protective pouring device for continuous casting and steel pouring according to claim 1, characterized in that: The protective shell (1) is provided with a connecting slot (5).

7. A portable protective pouring method for continuous casting steel pouring operation, characterized in that: A portable protective pouring device for continuous casting and steel pouring operation as defined in claims 1 to 5 is used and operated according to the following steps: a. Hold the two handles (7) of the protective shell (1) and fix the protective shell (1) under the ladle bottom steel shell (12) so that the protective shell (1) covers the connection between the tundish upper water inlet (13) and the immersion tundish lower water inlet (14), and the annular air blowing pipeline (3) is higher than the connection between the tundish upper water inlet (13) and the immersion tundish lower water inlet (14); b. Connect the protective gas pipeline joint (2) to the argon gas source and adjust the argon gas flow rate. At this time, the argon gas enters the interior of the protective shell (1) through the protective gas pipeline joint (2), the annular blowing pipeline (3) and the blowing hole (4), and forms an argon gas atmosphere at the connection between the upper water inlet (13) of the tundish and the lower water inlet (14) of the immersed tundish, thereby putting the steel pouring process in a protective state.

8. A portable protective pouring method for continuous casting and steel pouring according to claim 7, characterized in that: In the step a, the positional relationship between the blowing holes (4) in the circumferential direction of the annular blowing pipeline (3) and the connection between the upper water inlet (13) of the tundish and the lower water inlet (14) of the submerged tundish is: a horizontal spacing of 30-80 mm and a vertical spacing of 10-30 mm.

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