CN114273650A - Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method - Google Patents

Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method Download PDF

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Publication number
CN114273650A
CN114273650A CN202111476602.0A CN202111476602A CN114273650A CN 114273650 A CN114273650 A CN 114273650A CN 202111476602 A CN202111476602 A CN 202111476602A CN 114273650 A CN114273650 A CN 114273650A
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CN
China
Prior art keywords
vacuum
pouring
cover plate
sealing cover
cylinder
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Pending
Application number
CN202111476602.0A
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Chinese (zh)
Inventor
袁明
于广文
史以兵
顾金才
徐文斌
王光玮
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Zhangjiagang Guangda Special Material Co ltd
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Zhangjiagang Guangda Special Material Co ltd
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Priority to CN202111476602.0A priority Critical patent/CN114273650A/en
Publication of CN114273650A publication Critical patent/CN114273650A/en
Pending legal-status Critical Current

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Abstract

The application discloses a vacuum tank cover, a vacuum pouring system with the vacuum tank cover and a pouring method, and relates to the technical field of pouring. This application improves vacuum tank's sealing performance through set up sealed apron on the sprue gate, can reduce the time of evacuation in advance before the pouring by a wide margin, and is favorable to keeping the vacuum in the vacuum tank behind the evacuation in advance. When the argon blowing device is used, after the refining package is provided with the sealing ring, the pressure above and below the sealing cover plate is balanced through the balance pipe, the sealing cover plate is pulled away from the pouring gate through the air cylinder, pouring is achieved, and then the argon blowing time of the sliding plate before pouring is shortened.

Description

Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method
Technical Field
The application relates to the technical field of vacuum steel ingot pouring, in particular to a vacuum tank cover, a vacuum pouring device with the vacuum tank cover and a pouring method.
Background
At present, most of VC vacuum casting equipment has a tundish as a transition, and the tundish has the advantages of multi-ladle secondary combined casting and capability of producing larger steel ingots, and can produce more than 600 tons of steel ingots. However, when the tundish is used for casting, the problems of secondary oxidation, the blockage bar can not be closed and slag can not be discharged, the tundish material can be corroded and the like exist, and foreign impurities are brought in the casting process, so that the nondestructive testing of the forge piece is unqualified. For a small-tonnage VC steel ingot, the requirement for product flaw detection is often higher than that for a large-tonnage forging piece, and a tundish-free direct injection process is developed while the control capability of a vacuum ingot with a tundish is improved to the utmost extent.
For example, the chinese patent application with publication number CN110216273A discloses a "sealing device for direct casting of refining ladle in vacuum state", which includes a sealing cavity welded at the bottom of the refining ladle and a sealing ring welded at the upper end of a vacuum tank cover, wherein an opening is arranged at the middle position of the outer side of the sealing cavity, and a guide sleeve is installed at the middle part of the opening, so that a closed space is formed between the bottom of the refining ladle and the vacuum tank cover, thereby solving the overall sealing performance under the conditions of sliding water gap switch, sliding plate argon blowing, water gap argon blowing and the like during vacuum steel ingot casting, and achieving the purpose of direct casting of refining ladle in vacuum state.
However, the pouring gate of the vacuum tank in the above technical scheme is not provided with a sealing device, so that in actual operation, after the ladle is placed on a pouring position on the vacuum tank, a vacuum system needs to be started for pre-pumping, pouring can be started until the vacuum degree is less than or equal to 67Pa, and the waiting time is related to the capacity of the vacuum system and the system sealing condition and is generally 7-10 minutes. In order to ensure smooth casting, an argon blowing sliding plate is usually adopted to blow argon in the air exhaust process of a vacuum system, and long-time argon blowing before casting has great threat to the quality of molten steel and is very easy to bring foreign impurities.
In order to solve the problems, a plurality of measures are taken in the prior art, and the sliding plate argon blowing time is shortened by pre-pumping a vacuum pouring system. It is now common practice to place a sheet of aluminum at the gate location for sealing. However, the aluminum plate is deformed under atmospheric pressure, the sealing effect is poor, the aluminum plate is melted into steel after casting, the molten steel composition is affected, and steel types with extremely high requirements for B-type inclusions may cause product rejection or failure in the use process due to unqualified inclusions.
Disclosure of Invention
The utility model aims at providing a vacuum tank cover sets up a seal structure in its runner position, takes out time and slide and blows the problem of argon time overlength in advance before solving among the prior art vacuum steel ingot pouring.
In order to achieve the above purpose, the embodiments of the present application adopt the following technical solutions: a vacuum canister cover disposed on a vacuum canister, the vacuum canister cover comprising: the sealing ring is arranged above the vacuum tank cover and is used for installing a refining ladle; a gate disposed within the sealing ring; the sealing cover plate is arranged on the pouring gate and seals the pouring gate; the cylinder is provided with a telescopic rod, and the telescopic rod is connected with the sealing cover plate; the balance pipe is communicated with the pouring port and the vacuum tank.
In the technical scheme, the sealing cover plate is arranged on the pouring gate, so that the sealing performance of the vacuum tank is improved, the time of pre-vacuumizing before pouring can be greatly reduced, and the vacuum degree in the vacuum tank can be kept after pre-vacuumizing. When the argon blowing device is used, after the refining package is provided with the sealing ring, the pressure above and below the sealing cover plate is balanced through the balance pipe, the sealing cover plate is pulled away from the pouring gate through the air cylinder, pouring is achieved, and then the argon blowing time of the sliding plate before pouring is shortened.
Further, according to the embodiment of the application, a sealing gasket is arranged below the sealing cover plate.
Further, according to the embodiment of the present application, wherein, a balance valve is disposed on the balance pipe.
Further, according to this application embodiment, wherein, the cylinder is fixed mounting on the lateral wall of sealing ring, the telescopic link passes through the sealing ring.
Further, according to this application embodiment, wherein, be provided with the guide holder on the telescopic link, the guide holder is installed on the vacuum tank, be provided with through-hole one on the guide holder, the telescopic link passes through-hole one.
Further, according to this application embodiment, wherein, the tip of telescopic link is provided with the connecting piece, the connecting piece with sealed apron is connected.
Further, according to this application embodiment, wherein, sealed apron's side is provided with connecting portion, be provided with through-hole two on the connecting portion, the connecting piece passes through-hole two, the tip of connecting piece is provided with the barb.
Further, according to this application embodiment, wherein, the cylinder below is provided with the support, be provided with the baffle on the support, the baffle is used for blocking the cylinder.
Further, according to the embodiment of the application, wherein, the side of the pouring gate is provided with a support platform.
Further, according to the embodiment of the application, wherein, one side of the cylinder is provided with a cylinder scale.
Further, according to the embodiment of the application, a charging bell is arranged on the vacuum tank.
In order to achieve the purpose, the embodiment of the application also discloses a vacuum casting system which comprises the vacuum tank cover.
In order to achieve the above object, an embodiment of the present application further discloses a vacuum casting method, including the following steps:
pre-pumping: pre-vacuumizing the casting system under the condition that the sealing cover plate is closed to ensure that the vacuum degree is less than or equal to 67 Pa;
covering the steel ladle: opening argon of an argon blowing sliding plate, hoisting the steel ladle to the position above a vacuum tank cover, and opening a balance valve to balance pressure;
opening a sealing cover plate: confirming that the vacuum degree in the pouring system is less than or equal to 67Pa, operating the air cylinder to pull open the sealing cover plate, and confirming that the sealing cover plate is opened in place;
and (6) casting.
Compared with the prior art, the method has the following beneficial effects: this application improves vacuum tank's sealing performance through set up sealed apron on the sprue gate, can reduce the time of evacuation in advance before the pouring by a wide margin, and is favorable to keeping the vacuum in the vacuum tank behind the evacuation in advance. When the argon blowing device is used, after the refining package is provided with the sealing ring, the pressure above and below the sealing cover plate is balanced through the balance pipe, the sealing cover plate is pulled away from the pouring gate through the air cylinder, pouring is achieved, and then the argon blowing time of the sliding plate before pouring is shortened.
Drawings
The present application is further described below with reference to the drawings and examples.
Figure 1 is a schematic diagram of the construction of a vacuum canister lid of the present application.
Fig. 2 is a top view of fig. 1.
Fig. 3 is a partially enlarged view of a portion a in fig. 1.
Fig. 4 is a schematic structural diagram of the sealing cover plate in the present application.
Fig. 5 is a schematic view of the structure of the connector in the present application.
Fig. 6 is a partially enlarged view of fig. 2 at C.
Fig. 7 is a partially enlarged view of fig. 3 at B.
In the attached drawings
1. Vacuum tank cover 2, sealing ring 3 and pouring gate
4. Pouring gate 5, sealing cover plate 51, and sealing gasket
53. Connecting part 54, support table 6 and air cylinder
61. Telescopic rod 62, guide seat 63 and connecting piece
7. Support 71, stop 8 and balance pipe
81. Balance valve 9, cylinder scale 91 and guide wheel
92. Guide rail
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clear and fully described, embodiments of the present invention are further described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of some embodiments of the invention and are not limiting of the invention, and that all other embodiments obtained by those of ordinary skill in the art without the exercise of inventive faculty are within the scope of the invention.
In the description of the present invention, it should be noted that the terms "center", "middle", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "a," "an," "first," "second," "third," "fourth," "fifth," and "sixth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
For the purposes of simplicity and explanation, the principles of the embodiments are described by referring mainly to examples. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that the embodiments may be practiced without these specific details. In some instances, well-known methods and structures have not been described in detail so as not to unnecessarily obscure the embodiments. In addition, all embodiments may be used in combination with each other.
[ example 1 ]
Fig. 1 is a schematic structural view of a vacuum canister lid of the present embodiment, fig. 2 is a top view of fig. 1, and fig. 3 is a partial enlarged view of a portion a of fig. 1. As shown in fig. 1-3, a sealing ring 2 for mounting a refining ladle is arranged above a vacuum vessel cover 1 of the embodiment, a pouring gate 3 is arranged in the sealing ring 2, and the position of the pouring gate 3 corresponds to the position of a water gap of the refining ladle and is used for receiving molten steel from the refining ladle. Be provided with sealed apron 5 on pouring gate 3, sealed apron 5 shape and size and pouring gate 3 adaptation can cover pouring gate 3 completely and seal it. The side of sealed apron 5 is provided with cylinder 6, and this cylinder 6's telescopic link 61 is connected with sealed apron 5's side, can drive sealed apron 5 through the concertina movement of telescopic link and remove. The cylinder 6 is fixedly arranged on the outer side wall of the sealing ring 2, and the telescopic rod 61 penetrates through the sealing ring 2 to be connected with the sealing cover plate 5. The side of pouring gate 3 is provided with balance tube 8, and vacuum tank and pouring gate 3 are connected at the both ends of balance tube 8 for the pressure in balanced pouring gate 3 department and the vacuum tank is provided with balanced valve 81 on the balance tube 8.
Among the above-mentioned technical scheme, this embodiment is through setting up sealed apron on sprue gate 3, improves vacuum tank's sealing performance, can reduce the time of evacuation in advance before the pouring by a wide margin, and be favorable to keeping the vacuum degree in the vacuum tank after evacuation in advance, after packing the last sealing ring 2 of refining, open balanced valve 81 for the pressure balance about sealed apron 5, rethread cylinder 6 drags sealed apron 5 from the sprue gate, realizes opening and waters, and then shortens the slide argon blowing time before the pouring.
Among them, the lower end of the sealing cover plate 5 is provided with the gasket 51, so that the sealing performance thereof can be further improved.
The telescopic rod 61 is provided with a guide seat 62, the guide seat 62 is fixedly installed on the vacuum tank cover 1, a first through hole is formed in the guide seat 62, and the telescopic rod 61 penetrates through the first through hole.
The end of the telescopic rod 61 is provided with a connecting piece 63, and the connecting piece 63 is connected with the sealing cover plate 5. Specifically, the structure of the sealing cover 5 is shown in fig. 4, and the structure of the connecting member 63 is shown in fig. 5. The lateral wall of sealed apron 5 is provided with connecting portion 53, is provided with through-hole two on connecting portion 53, and connecting piece 63 passes this through-hole two and the tip of its connecting piece 63 is provided with the barb for connecting piece 63 hangs and establishes in connecting portion 53, realizes being connected of telescopic link 61 and sealed apron 5 and be detachable construction, if sealed apron produces deformation or breakage, can dismantle the replacement.
A bracket 7 is arranged below the air cylinder 6, the bracket 7 is fixed on the side wall of the vacuum tank cover 1, and a baffle 71 is arranged on the bracket 7, and the baffle 71 is used for blocking the air cylinder 7 to prevent the air cylinder 7 from being displaced.
Fig. 6 is a partially enlarged view of a portion C in fig. 2, and in fig. 6, a support stand 54 is provided on a side of the pouring gate 3. The purpose of the abutment table 54 is to provide a supporting force when the sealing cover plate 5 is to be detached from the pouring opening 3. The support platform 54 is specifically configured as two elongated blocks, which are transversely disposed on both sides of the pouring gate 3 and the telescopic rod 61.
[ example 2 ]
The present embodiment is different from embodiment 1 in that a cylinder scale 9 is provided at one side of the cylinder 6 to display the telescopic position of the telescopic rod 61, thereby determining the position of the sealing cover 5. Specifically, fig. 7 is a partial enlarged view of a portion B in fig. 3, and in conjunction with fig. 6-7, the cylinder scale 9 is a long rod, which is disposed at one side of the cylinder 6 and penetrates through the side wall of the sealing ring 2. One end of the cylinder scale 9 is exposed outside the sealing ring 2, the other end of the cylinder scale is connected with the end of the telescopic rod 61, and when the telescopic rod 61 stretches, the cylinder scale 9 is driven to move. When the refining bag is installed on the sealing ring 2, the situation in the sealing ring 2 is covered, namely, the positions of the telescopic rod 61 and the sealing cover plate 5 can be determined through the cylinder scale exposed outside.
Specifically, below the cylinder scale 9, a guide wheel 91 is provided, the guide wheel 91 being mounted on a guide rail 92, the guide rail 92 being mounted within the sealing ring 2.
[ example 3 ]
The difference between the embodiment and the embodiment 1 is that a charging bell 4 is further arranged on the vacuum tank cover 1, and the charging bell 4 is used for connecting a quick coupling.
[ example 4 ]
This embodiment discloses a vacuum casting apparatus having a vacuum can lid as described in the previous embodiments.
[ example 5 ]
The embodiment discloses a vacuum casting method, and the vacuum casting device in the embodiment comprises the following steps:
pre-pumping: pre-vacuumizing the casting system under the condition that the sealing cover plate 5 is closed to ensure that the vacuum degree is less than or equal to 67 Pa;
covering the steel ladle: opening argon of an argon blowing sliding plate, hoisting the steel ladle to the position above a vacuum tank cover, and opening a balance valve to balance pressure;
opening a sealing cover plate: confirming that the vacuum degree in the pouring system is less than or equal to 67Pa, operating the air cylinder to pull open the sealing cover plate, and confirming that the sealing cover plate is opened in place;
and (6) casting.
The vacuum pouring device is used for pouring, the vacuum degree of a pouring system during pouring can be guaranteed to be less than or equal to 40Pa, the waiting time after the steel ladle is covered is 40-60s, and the argon blowing time of the sliding plate is shortened. The sealing cover plate 5 can be recycled for more than 10 times, the power system is stable, 100% uncovering can be ensured, and the self-opening rate of the ladle can also reach 100%.
Although the illustrative embodiments of the present application have been described above to enable those skilled in the art to understand the present application, the present application is not limited to the scope of the embodiments, and various modifications within the spirit and scope of the present application defined and determined by the appended claims will be apparent to those skilled in the art from this disclosure.

Claims (13)

1. A vacuum can lid disposed on a vacuum can, the vacuum can lid comprising:
the sealing ring is arranged above the vacuum tank cover and is used for installing a refining ladle;
a gate disposed within the sealing ring;
the sealing cover plate is arranged on the pouring gate and seals the pouring gate;
the cylinder is provided with a telescopic rod, and the telescopic rod is connected with the sealing cover plate;
the balance pipe is communicated with the pouring port and the vacuum tank.
2. The vacuum can lid according to claim 1, wherein a gasket is disposed under the sealing cover.
3. The vacuum can lid according to claim 1, wherein the balancing pipe is provided with a balancing valve.
4. The vacuum canister lid according to claim 1, wherein the cylinder is fixedly mounted on the outer sidewall of the sealing ring, and the expansion rod passes through the sealing ring.
5. The vacuum can cover according to claim 1, wherein the extension rod is provided with a guide seat, the guide seat is mounted on the vacuum can, the guide seat is provided with a first through hole, and the extension rod passes through the first through hole.
6. The vacuum canister lid according to claim 1, wherein the end of the telescoping rod is provided with a connector that is connected to the sealing cover plate.
7. The vacuum can cover as claimed in claim 6, wherein the sealing cover plate has a connecting portion at its side edge, a second through hole is formed in the connecting portion, the connecting member passes through the second through hole, and a barb is formed at the end of the connecting member.
8. The vacuum can cover according to claim 1, wherein a support is provided under the cylinder, and a baffle is provided on the support for blocking the cylinder.
9. The vacuum can lid according to claim 1, wherein the side of the pouring opening is provided with a support platform.
10. The vacuum can lid as defined in claim 1, wherein a cylinder scale is provided on one side of said cylinder.
11. The vacuum can lid of claim 1 wherein said vacuum can is provided with a filler bell.
12. A vacuum casting system comprising a vacuum canister lid according to any one of claims 1 to 11.
13. A vacuum casting method, comprising the steps of:
pre-pumping: pre-vacuumizing the casting system under the condition that the sealing cover plate is closed to ensure that the vacuum degree is less than or equal to 67 Pa;
covering the steel ladle: opening argon of an argon blowing sliding plate, hoisting the steel ladle to the position above a vacuum tank cover, and opening a balance valve to balance pressure;
opening a sealing cover plate: confirming that the vacuum degree in the pouring system is less than or equal to 67Pa, operating the air cylinder to pull open the sealing cover plate, and confirming that the sealing cover plate is opened in place;
and (6) casting.
CN202111476602.0A 2021-12-06 2021-12-06 Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method Pending CN114273650A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111476602.0A CN114273650A (en) 2021-12-06 2021-12-06 Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111476602.0A CN114273650A (en) 2021-12-06 2021-12-06 Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method

Publications (1)

Publication Number Publication Date
CN114273650A true CN114273650A (en) 2022-04-05

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ID=80870919

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Application Number Title Priority Date Filing Date
CN202111476602.0A Pending CN114273650A (en) 2021-12-06 2021-12-06 Vacuum tank cover, vacuum pouring device with vacuum tank cover and pouring method

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1168680A (en) * 1957-02-26 1958-12-12 Improved method and device for the ingot casting of steels and other ferrous compounds
CH448398A (en) * 1965-12-29 1967-12-15 Von Roll Ag Device for degassing metal, in particular steel
US4037644A (en) * 1974-09-23 1977-07-26 Vereinigte Edelstahlwerke Aktiengesellschaft (Vew) Process for casting steel ingots under a vacuum
CN104707984A (en) * 2015-03-31 2015-06-17 中国重型机械研究院股份公司 Automatic control system for pouring box plug rod for vacuum casting
CN110216273A (en) * 2019-07-16 2019-09-10 上海电气上重铸锻有限公司 It is a kind of for refining the sealing device being directly poured under packet vacuum state

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1168680A (en) * 1957-02-26 1958-12-12 Improved method and device for the ingot casting of steels and other ferrous compounds
CH448398A (en) * 1965-12-29 1967-12-15 Von Roll Ag Device for degassing metal, in particular steel
US4037644A (en) * 1974-09-23 1977-07-26 Vereinigte Edelstahlwerke Aktiengesellschaft (Vew) Process for casting steel ingots under a vacuum
CN104707984A (en) * 2015-03-31 2015-06-17 中国重型机械研究院股份公司 Automatic control system for pouring box plug rod for vacuum casting
CN110216273A (en) * 2019-07-16 2019-09-10 上海电气上重铸锻有限公司 It is a kind of for refining the sealing device being directly poured under packet vacuum state

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