Dummy ingot hook assembly used for continuous casting of stainless steel small square and round billets and using method

Abstract

The invention provides a dummy ingot hook assembly for continuous casting of stainless steel small square billets and round billets and a using method of the dummy ingot hook assembly. The dummy ingot hook (1) and the dummy ingot head (2) are detachably connected with each other; the invention further relates to a using method of the dummy ingot hook assembly. The using method comprises the steps that firstly, casting preparation is conducted; 2, casting is started, and the dummy bar hook (1) is connected with the dummy bar head (2); and 3, automatic ingot stripping is completed. The dummy ingot hook assembly is simple in structure, convenient to operate, simple in connection mode and convenient to disassemble, automatic ingot stripping can be achieved, the continuous casting emergence time is greatly shortened, and the breakout risk is reduced; the dummy bar head is effectively protected, and the service life of the dummy bar head is prolonged; the dummy ingot hook is made of common carbon steel, so that the production cost is reduced.

Description

Technical Field

[0001] The invention belongs to the field of stainless steel continuous casting, and in particular relates to an ingot starter hook assembly used in stainless steel small square and round billet continuous casting and a use method thereof. Background Art

[0002] Before the continuous casting machine starts pouring, the dummy rod needs to be sent from the secondary cooling zone into the copper tube of the crystallizer. At present, most of the dummy heads are designed with a dovetail groove structure. After the dummy head is sent to the set position, an asbestos rope is inserted between the dummy head and the copper tube of the crystallizer. Then some cold materials such as iron filings are put in. After the pouring starts, the high-temperature molten steel is injected into the crystallizer to melt the cold materials to form a billet. The billet in the dovetail groove is connected to the dummy rod, and the billet is gradually pulled out of the crystallizer through the straightening machine to realize continuous casting production.

[0003] However, for small square and round stainless steel billets, due to the relatively high pulling speed, the liquidus temperature of stainless steel is more than 30°C lower than that of carbon steel. Even if the molten steel in the tundish has a certain degree of superheat during casting, the molten steel is strongly cooled after entering the crystallizer, resulting in a rapid drop in temperature, and the cold material often cannot be completely melted. Moreover, since the pulling speed of small square and round billets is relatively high, the emergence time cannot be too short, resulting in the formation of a billet shell of a certain strength after the billet emerges from the crystallizer, but there is still a large amount of liquid steel in the middle part of the billet. If the pulling speed is not well controlled, it is particularly easy to break the billet, resulting in steel leakage accidents.

[0004] Therefore, there is an urgent need for a dummy hook assembly and method for continuous casting of small square and round stainless steel billets to overcome the bottleneck of the existing technology. Summary of the invention

[0005] The purpose of the invention is to provide a dummy hook assembly used for continuous casting of small square and round stainless steel billets and a using method thereof.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention relates to a dummy hook assembly for continuous casting of stainless steel small square billets and round billets, comprising: a dummy hook 1 and a dummy head 2, wherein the dummy hook 1 and the dummy head 2 are detachably connected;

[0008] The dummy hook 1 comprises: a plurality of steel bars 1-1, a first round bar 1-2, a bottom plate 1-3, a second round bar 1-4, a third round bar 1-5, and a fourth round bar 1-6; the third round bar 1-5 and the fourth round bar 1-6 are respectively arranged at the upper and lower ends of the bottom plate 1-3; the first round bar 1-2 is inserted on the fourth round bar 1-6, and the second round bar 1-4 is inserted on the third round bar 1-5, and is arranged parallel to the first round bar 1-2; the steel bar 1-1 is vertically arranged on the upper end surface of the bottom plate 1-3, and is surrounded by the fourth round bar 1-6; the components of the dummy hook 1 are connected by welding;

[0009] The ingot starter 2 comprises: a first groove 2-1, a second groove 2-2, and a rotating hole 2-3.

[0010] Arranging the first round rod 1-2 at the fourth round rod 1-6 can reduce the area in the middle part that needs to be filled with liquid steel, and can increase the adhesion between the ingot hook 1 and the molten steel 3, to ensure that the ingot hook 1 does not separate from the billet during billet drawing; this greatly shortens the emergence time of pouring, and at the same time can ensure that the billet leaving the crystallizer has sufficient strength to meet the billet drawing needs.

[0011] A plurality of steel bars 1-1 are arranged on the outer ring of the bottom plate 1-3, and the spacing between each steel bar 1-1 is more than 20 mm. The purpose is that since stainless steel has high viscosity and poor fluidity, if the spacing is too close (when the spacing is less than 20 mm), the flow of molten steel will be seriously affected, resulting in the molten steel being unable to fully fill the end of the ingot hook.

[0012] Preferably, the diameter of the steel bar 1-1 is 10 mm, and the length h1 is 100-150 mm.

[0013] Preferably, the thickness of the bottom plate 1-3 is 10 to 25 mm, and its size and shape are related to the crystallizer copper tube 3. When a round billet is used, the bottom plate 1-3 is round, and when a square billet is used, the bottom plate 1-3 is square, and the chamfers of the four corners are larger than the inner chamfers of the crystallizer copper tube 3. The size of the bottom plate 1-3 is smaller than the crystallizer copper tube 3, and a gap of about 5 mm is left on one side.

[0014] Preferably, the diameters Φd1 of the first round rod 1 - 2 and the second round rod 1 - 4 are equal, and 20 mm ≤ Φd1 ≤ Φd2.

[0015] Preferably, the diameters Φd2 of the third round rod 1-5 and the fourth round rod 1-6 are equal, and 50 mm ≤ Φd2 ≤ 2 / 5 of the thickness.

[0016] Preferably, the first groove 2-1 is the working area of ​​the third round rod 1-5 when the ingot hook 1 is connected to the ingot head 2; the second groove 2-2 is the position where the second round rod 1-4 is connected to the ingot head 2; the rotating hole 2-3 is the position where the ingot head 2 is connected to the ingot rod, and the ingot head 2 rotates around the rotating hole 2-3 when stripping the ingot.

[0017] Preferably, the opening slope of the second groove 2 - 2 is 10°.

[0018] Preferably, the distance between the thickness center of the starter head 2 and the slope of the second groove 2-2 is 5 mm greater than the diameter Φd2 of the third round rod 1-5.

[0019] Preferably, the chamfer angle a of the starter head 2 is 10° to 20°.

[0020] The present invention also relates to a method for using the aforementioned dummy hook assembly for continuous casting of stainless steel small square billets and round billets, comprising the following steps:

[0021] Step 1, preparation for firing: first, put the dummy head 2 into the copper tube 3 of the crystallizer, continue to push the dummy rod upward until the dummy head 2 is exposed 300mm from the upper mouth of the copper tube 3 of the crystallizer, hang the second round bar 1-4 at the second groove 2-2, start the straightening machine to pull the dummy rod downward along the billet discharge direction until the dummy head 2 reaches the set position, insert a certain amount of asbestos rope between the bottom plate 1-3 and the copper tube 3 of the crystallizer, press it with an iron brazing rod, lay asbestos cloth on the top surface of the bottom plate 1-3, and sprinkle cold material or iron filings on it, that is, the dummy is sealed, and wait for molten steel 4 to prepare for pouring;

[0022] Step 2, pouring: the molten steel 4 in the tundish enters the copper tube 3 of the crystallizer through the immersion nozzle. After the high-temperature molten steel 4 meets the cold material, the cold material melts quickly, and the steel bar 1-1 contacts the high-temperature molten steel 4, so that the high-temperature molten steel is quickly cooled to form a solidified billet shell; and because the ingot hook 1 is provided with a fourth round rod 1-6, the middle part does not need to be filled with high-temperature molten steel, and because the round rod 1-6 in the middle of the ingot hook 1 is strong enough, the solidified molten steel 4 and the fourth round rod 1-6 are solidified together, and the ingot hook 1 is connected to the ingot head 2; there is a fourth round rod 1-6 in the middle of the upper part of the ingot hook 1, and the fourth round rod 1-6 is provided with a first round rod 1-2 with a slightly smaller diameter, so that the area in the middle part where the liquid molten steel needs to be filled can be reduced, and the bonding between the ingot hook 1 and the molten steel 4 can be increased to ensure that the ingot hook is not separated from the billet when drawing. In this way, the emergence time of pouring is greatly shortened, and at the same time, it can ensure that the billet out of the crystallizer has sufficient strength to meet the needs of billet drawing.

[0023] Since the dummy hook 1 is provided with the protection of the bottom plate 1-3, the high-temperature molten steel 4 will not contact the dummy head 2, thus extending the service life of the dummy head 2 and saving production costs.

[0024] Step 3, after the ingot comes out of the straightening machine and reaches the stripping position, the stripping roller 5 rises, the ingot head 2 swings upward along the pin connecting the ingot head 2 and the ingot chain, and the second round rod 1-4 at the lower part of the ingot hook 1 comes out of the second groove 2-2, and the front roller table rotates at a high speed in the direction of billet discharge, transporting the ingot rod above the roller table to the set position, completing the automatic stripping.

[0025] The present invention has the following advantages:

[0026] (1) The ingot guide hook assembly used in the continuous casting of small square and round stainless steel billets involved in the present invention has a simple structure and is easy to operate.

[0027] (2) The ingot hook assembly used in the continuous casting of small square and round stainless steel billets involved in the present invention has a simple component connection method and is easy to operate, which greatly shortens the emergence time of continuous casting and reduces the risk of steel leakage.

[0028] (3) Effectively protect the ingot head and increase its service life.

[0029] (4) Automatic spindle stripping can be achieved.

[0030] (5) The ingot starter hook assembly used for continuous casting of small square and round stainless steel billets involved in the present invention is made of ordinary carbon steel, thereby reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the dummy hook;

[0032] Figure 2 It is a side view of the dummy hook;

[0033] Figure 3 Draw head for use with draw hook

[0034] Figure 4 Elevation side view of the dummy head for use with the dummy hook

[0035] Figure 5 A top view of a dummy head used in conjunction with a dummy hook;

[0036] Figure 6 The state display diagram of the upper mouth of the crystallizer is sent out by the ingot starter;

[0037] Figure 7 A state display diagram of installing a dummy hook for the dummy head to be sent out of the upper opening of the crystallizer;

[0038] Figure 8 The state display diagram of installing the ingot hook on the ingot head and sending it to the designated position for capping;

[0039] Fig. 9 This is a diagram showing the relationship between the molten steel, the ingot hook and the ingot head after pouring;

[0040] Fig.10 The dummy rod is pulling the ingot to the stripping position.

[0041] Fig.11 This is a diagram showing the debonding state;

[0042] The attached drawings are marked as follows: 1 is the ingot hook, 2 is the ingot head, 3 is the copper tube of the crystallizer, 4 is the molten steel, 5 is the stripping roller, and 6 is the ingot; 1-1 is the steel bar, 1-2 is the first round rod, 1-3 is the bottom plate, 1-4 is the second round rod, 1-5 is the third round rod, and 1-6 is the fourth round rod; 2-1 is the first groove, 2-2 is the second groove, and 2-3 is the rotating hole. DETAILED DESCRIPTION

[0043] The present invention is described in detail below in conjunction with specific embodiments. It should be noted that the following embodiments are only further descriptions of the present invention, but the protection scope of the present invention is not limited to the following embodiments.

[0044] Example

[0045] This embodiment relates to a dummy hook assembly used for continuous casting of small square and round stainless steel billets, comprising: a dummy hook 1 and a dummy head 2, wherein the dummy hook 1 and the dummy head 2 are detachably connected;

[0046] Among them, see Figure 1 As shown, the dummy hook 1 comprises: a plurality of steel bars 1-1, a first round bar 1-2, a bottom plate 1-3, a second round bar 1-4, a third round bar 1-5, and a fourth round bar 1-6; the third round bar 1-5 and the fourth round bar 1-6 are respectively arranged at the upper and lower ends of the bottom plate 1-3; the first round bar 1-2 is inserted and arranged on the fourth round bar 1-6, and the second round bar 1-4 is inserted and arranged on the third round bar 1-5, and is arranged parallel to the first round bar 1-2; the steel bar 1-1 is vertically arranged on the upper end surface of the bottom plate 1-3, and is arranged around the fourth round bar 1-6; the various components of the dummy hook 1 are welded;

[0047] The dummy hook 1 is a welded part, the bottom plate 1-3 has a hole in the middle welded on the third round rod 1-5, the third round rod 1-5 and the fourth round rod 1-6 are separated by the bottom plate 1-3; the top of the bottom plate 1-3 is welded with a steel bar 1-1 with a diameter of 10mm and a length h1 of 100mm on the outer ring;

[0048] See Figure 2 As shown, the thickness of the bottom plate 1-3 is generally 10-25 mm, and its size and shape are related to the crystallizer copper tube 3. When the round billet is used, the bottom plate 1-3 is round, and when the square billet is used, the bottom plate 1-3 is square, and the four corner chamfers are larger than the inner chamfers of the crystallizer copper tube 3. The size of the bottom plate 1-3 is smaller than the crystallizer copper tube 3, and a gap of about 5 mm is left on one side. The diameter of the steel bar roller 1-1 is about 10 mm, the length h1 is between 100 and 150, and the length h2 is between (50 and 100).

[0049] The diameter Φd1 of the first round rod 1-2 and the second round rod 1-4 is related to the casting section, but the minimum shall not be less than 20mm. The diameter Φd2 of the third round rod 1-5 and the fourth round rod 1-6 is related to the casting section, but the minimum shall not be less than 50mm, and can be appropriately increased when the section is large; d3 is the length, width of 1-3 or the diameter of 1-3 when it is a round billet.

[0050] See Figure 3 As shown, the ingot starter head 2 used in conjunction with the ingot starter hook 1 includes: a first groove 2-1, a second groove 2-2, and a rotation hole 2-3;

[0051] The first groove 2-1 is the working area of ​​the round rod 1-5 when the ingot hook 1 is connected to the ingot head 2; the second groove 2-2 is the part where the second round rod 1-4 is connected to the ingot head 2. The rotating hole 2-3 is the other connection position between the ingot head 2 and the ingot rod, and the ingot head 2 rotates around the rotating hole 2-3 when the ingot is stripped.

[0052] like Figure 4 As shown, the thickness g of the ingot starter 2 is 5 mm less than the casting section, and the width e of the second groove 2-2 is 2 mm larger than the round rod 1-5. The opening slope b of the second groove 2-2 is about 10°, which is convenient for stripping. The distance between the thickness center of the ingot starter 2 and the slope of the second groove 2-2 is 5 mm larger than the diameter Φd2 of the round rod 1-5. This allows the third round rod 1-5 of the ingot starter hook 1 to be stuck in the second groove 2-2 of the ingot starter 2, but not to be easily disengaged, and is convenient for stripping when stripping.

[0053] The chamfer angle a of the starter head 2 is between 10° and 20°.

[0054] See Figure 4 In the figure, the value of f is half of the thickness of the starter head plus the sum of the diameters of the third round bars 1-5 plus 5 mm. Figure 4 In the figure, j is the distance from the center of the groove 2-2 to the end surface of the ingot starter 2.

[0055] See Figure 5 As shown, m is the width of the casting section minus 5 mm, n is the width of the first groove 2-1, which can be 2 mm larger than the third round rod 1-5. j can be 2 mm smaller than h2. Rn is the internal chamfer of the first groove 2-1, and its size is half of the width of the first groove 2-1.

[0056] See Figure 6 As shown, the ingot starter 2 is sent out of the upper end of the crystallizer copper tube 3 by about 300 mm.

[0057] See Figure 7As shown, after the starter head 2 is sent out of the upper end of the crystallizer copper tube 3 by 300 mm, the second round rod 1-4 of the starter hook 2 is installed in the second groove 2-2 of the starter head 2. The third round rod 1-5 of the starter hook is installed in the first groove 2-1 of the starter head 2.

[0058] See Figure 8 As shown, after the dummy hook 1 is installed on the dummy head 2, the dummy rod is sent to the set position, asbestos cloth is laid above the bottom plate 1-3 of the dummy hook 1, and asbestos rope is inserted between the bottom plate 1-3 of the dummy hook 1 and the crystallizer copper tube 3. Then, cold material is sprinkled on the asbestos cloth to prepare for casting.

[0059] See Fig. 9 As shown, after the high-temperature molten steel 4 enters the copper tube 3 of the crystallizer after pouring, the relationship between the high-temperature molten steel 4, the ingot hook 1, and the ingot head 2 is shown.

[0060] See Fig.10 As shown, the dummy head 2 pulls the dummy hook 1, and the dummy hook 1 is bonded to the ingot 6 to reach the stripping position.

[0061] See Fig.11 As shown, the ingot starter head 2 pulls the ingot starter hook 1, and the ingot starter hook 1 is bonded with the ingot 6 to reach the stripping position. After the stripping roller 5 is raised, the ingot starter head 2 rotates along the pin shaft arranged in cooperation with the rotating hole 2-3, and the second round rod 1-4 of the ingot starter hook 1 is stripped out of the second groove 2-2 of the ingot starter head 2, completing the separation of the ingot starter hook 1 and the ingot starter head 2, and the roller conveyor transports the ingot starter rod to the set position at high speed to complete the stripping work.

[0062] Working principle of the present invention:

[0063] First, send the ingot starter 2 to the top of the crystallizer copper tube 3, install the ingot starter hook 1 in the groove of the ingot starter 2, and send the ingot starter hook 1 to the set position. Insert a certain amount of asbestos rope between the bottom plate 1-3 and the crystallizer copper tube 3, press it with an iron braze, lay asbestos cloth on the top surface of the bottom plate 1-3, and sprinkle some cold material on it to complete the sealing of the ingot and prepare for pouring.

[0064] Secondly, after pouring, the outer ring of the dummy hook 1 is provided with a plurality of steel bars 1-1 in contact with the molten steel 4, so that the high-temperature molten steel is rapidly cooled to form a solidified shell. Since the fourth round rod 1-6 is provided in the middle of the dummy hook 1, it is not necessary to fill the high-temperature molten steel. The solidified molten steel 4 is solidified together with the fourth round rod 1-6 and connected with the dummy head 2, thereby ensuring the connection between the dummy hook 1 and the dummy head 2; since the fourth round rod 1-6 is provided with a first round rod 1-2 with a slightly smaller diameter, the bonding between the dummy hook 1 and the molten steel 4 is increased, and the dummy hook 1 does not separate from the cast billet during billet drawing, shortening the emergence time of pouring, ensuring the strength of the shell of the billet out of the crystallizer, and meeting the billet drawing requirements.

[0065] Finally, after the ingot comes out of the straightening machine and reaches the stripping position, the stripping roller 5 rises, and the automatic stripping can be completed.

[0066] Compared with the prior art, the present invention has the following advantages: the ingot guide hook assembly of the present invention has a simple structure, is easy to operate, has a simple connection method, is easy to disassemble, can realize automatic ingot stripping, greatly shortens the emergence time of continuous casting, and reduces the risk of steel leakage; effectively protects the ingot guide head and increases the service life of the ingot guide head; the ingot guide hook involved in the present invention is made of ordinary carbon steel, which reduces the production cost.

[0067] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which will not affect the essence of the present invention.

Claims

1. A dummy hook assembly for continuous casting of stainless steel billets and round billets, characterized in that: include: A starter hook (1) and a starter head (2), wherein the starter hook (1) and the starter head (2) are detachably connected; The dummy hook (1) comprises: a plurality of steel bars (1-1), a first round bar (1-2), a bottom plate (1-3), a second round bar (1-4), a third round bar (1-5), and a fourth round bar (1-6); the third round bar (1-5) and the fourth round bar (1-6) are respectively arranged at the upper and lower ends of the bottom plate (1-3); the first round bar (1-2) is inserted and arranged on the fourth round bar (1-6), and the second round bar (1-4) is inserted and arranged on the third round bar (1-5), and is arranged parallel to the first round bar (1-2); the steel bar (1-1) is vertically arranged on the upper end surface of the bottom plate (1-3), and is arranged around the fourth round bar (1-6); The ingot starter (2) comprises: a first groove (2-1), a second groove (2-2), and a rotating hole (2-3).

2. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The diameter of the steel bar (1-1) is 10 mm, and its length h1 is 100-150 mm.

3. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The thickness of the bottom plate (1-3) is 10 to 25 mm.

4. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The diameters Φd1 of the first round rod (1-2) and the second round rod (1-4) are equal, and 20mm≤Φd1≤Φd2.

5. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The diameters Φd2 of the third round rod (1-5) and the fourth round rod (1-6) are equal, and 50mm≤Φd2≤2 / 5 of the thickness.

6. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The first groove (2-1) is the working area of ​​the third round rod (1-5) when the dummy hook (1) is connected to the dummy head (2); the second groove (2-2) is the position where the second round rod (1-4) is connected to the dummy head (2); the rotating hole (2-3) is the position where the dummy head (2) is connected to the dummy rod, and the dummy head (2) rotates around the rotating hole (2-3) when the dummy head (2) is stripped.

7. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The opening inclination of the second groove (2-2) is 10°.

8. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The distance between the thickness center of the ingot starter (2) and the slope of the second groove (2-2) is 5 mm greater than the diameter Φd2 of the third round rod (1-5).

9. The dummy hook assembly for continuous casting of stainless steel billets and round billets according to claim 1, characterized in that: The chamfer angle a of the starter head (2) is between 10° and 20°.

10. A method for using the dummy hook assembly for continuous casting of stainless steel billets and round billets as claimed in claim 1, characterized in that: The following steps are involved: Step 1, preparation for firing: first, insert the dummy head (2) into the copper tube (3) of the crystallizer, continue to push the dummy rod upward until the dummy head (2) is exposed 300 mm above the upper end of the copper tube (3) of the crystallizer, hang the second round bar (1-4) at the second groove (2-2), start the straightening machine to pull the dummy rod downward along the billet discharge direction until the dummy head (2) reaches the set position, insert a certain amount of asbestos rope between the bottom plate (1-3) and the copper tube (3) of the crystallizer, press it with an iron brazing rod, lay asbestos cloth on the top surface of the bottom plate (1-3), and sprinkle cold material or iron filings on it, thus completing the sealing of the dummy head, waiting for molten steel (4), and preparing to start pouring; Step 2, pouring: the molten steel (4) in the tundish enters the copper tube (3) of the crystallizer through the immersion nozzle. After the high-temperature molten steel (4) meets the cold material, the cold material melts rapidly. The steel bar (1-1) contacts the high-temperature molten steel (4), so that the high-temperature molten steel is rapidly cooled to form a solidified shell. The solidified molten steel (4) and the fourth round rod (1-6) are solidified together, and the ingot hook (1) is connected to the ingot head (2). Step 3, after the ingot is out of the straightening machine and reaches the stripping position, the stripping roller (5) rises, the dummy head (2) swings upward along the pin connecting the dummy head (2) and the dummy chain, the second round rod (1-4) at the lower part of the dummy hook (1) comes out of the second groove (2-2), the front roller table rotates at high speed in the direction of billet discharging, and the dummy rod above the roller table is transported to the set position, completing the automatic stripping.

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