Large-sized ductile iron casting molten iron pouring equipment and molten iron preparation method
By combining a multi-layered pouring basin, a plug rod, and an inoculation hopper, the problems of high equipment cost and casting quality in the production of large ductile iron castings are solved, and a method for efficient production of large castings is realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-02
- Publication Date
- 2026-06-12
AI Technical Summary
When producing large ductile iron castings, existing foundries need to invest in a lot of large equipment, and primary slag on the surface of the molten iron ladle is easily drawn into the pouring basin, affecting the pouring quality and resulting in high equipment costs.
The design employs a multi-layered pouring basin and a plug rod, combined with an inoculation hopper, to ensure that slag does not enter the casting cavity during the first pouring stage by distributing molten iron multiple times, thereby reducing equipment requirements.
It enables the production of castings larger than 50 tons without increasing equipment investment, reducing casting costs and ensuring casting quality.
Smart Images
Figure CN122184277A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of ductile iron casting, and in particular to a large ductile iron casting molten iron pouring equipment and a molten iron preparation method. Background Technology
[0002] The ductile iron castings produced by foundries are becoming increasingly larger, ranging in weight from 50 tons to 100-150 tons. This necessitates foundries investing in larger equipment, such as electric furnaces and overhead cranes.
[0003] Currently, the foundry produces ductile iron castings with a weight of 50 tons, requiring two 25-ton melting electric furnaces and two pouring cranes. The pouring operation is as follows: First, melt two furnaces of 25 tons of molten iron; second, perform spheroidization treatment in the two 25-ton ladles; third, remove slag from the spheroidized molten iron in the two 25-ton ladles; fourth, the two pouring cranes simultaneously lift the two 25-ton ladles and pour the molten iron into the two pouring basins, thus beginning the pouring process and injecting the molten iron into the mold cavity.
[0004] However, in the above-mentioned casting method, primary slag on the surface of the molten iron ladle will be drawn into the pouring basin, affecting the casting quality. In addition, the foundry needs to install at least two or more large melting electric furnaces (capacity of 25 tons or more), two 50-ton overhead cranes, and large-volume quantitative ladles. This means that the foundry needs to invest more in equipment to cast castings weighing more than 50 tons. Therefore, there is a need for a method that can produce castings weighing more than 50 tons using the existing casting equipment and molten iron preparation method with a capacity of a dozen tons. Summary of the Invention
[0005] This application aims to at least partially address one of the technical problems in the related art.
[0006] Therefore, one objective of this application is to provide a large ductile iron casting molten iron pouring device, which, through the setting of a multi-layer pouring basin, eliminates the need for a filter screen and prevents primary slag from entering the casting, thus ensuring that primary slag does not enter the casting cavity.
[0007] To achieve the above objectives, this application proposes a large ductile iron casting molten iron pouring device, comprising a sand mold, multi-layer pouring basins, a stopper rod, and an inoculation hopper, wherein the sand mold has a gating channel; the multi-layer pouring basins are respectively arranged on the sand mold, and each layer of pouring basins is interconnected; the stopper rod and the inoculation hopper are arranged on the upper pouring basin.
[0008] In addition, the large ductile iron casting equipment proposed above in this application may also have the following additional technical features: In one embodiment of this application, the multi-layer gating basin includes a first gating basin and a second gating basin, wherein the first gating basin is disposed on the sand mold and communicates with the gating system of the sand mold; the second gating basin is stacked on the first gating basin; a plug bar is inserted into the gating gate of the second gating basin; and an inoculation hopper is disposed on the second gating basin.
[0009] In one embodiment of this application, the diameter of the plug rod increases from bottom to top, and the maximum diameter of the plug rod is adapted to the gate diameter of the second gate basin.
[0010] The second objective of this application is to provide a method for preparing molten iron for large ductile iron castings, which adopts a multi-dispensing method, enabling foundries with existing casting equipment and molten iron preparation methods of a dozen tons to produce castings with a weight of more than 50 tons, thereby reducing casting costs.
[0011] To achieve the above objectives, this application proposes a method for preparing molten iron for large ductile iron castings, applicable to the molten iron casting equipment for large ductile iron castings as described in any one of claims 1-3, comprising the following steps: Iron preparation: Three 12.5-ton electric furnaces and two 13-ton ladles are used for multiple batches of melting and composition adjustment. The molten iron is then collected into two 25-ton ladles through batch spheroidization treatment. Iron pouring: One 25-ton ladle of molten iron is lifted by a crane to the upper pouring basin to pour the molten iron, and then another 25-ton ladle of molten iron is lifted by a crane to the top of the upper pouring basin. Open the plug rod, and the molten iron in the upper pouring basin flows into the sand mold's gating channel through the lower pouring basin. At the same time, molten iron from another 25-ton ladle is added to the upper pouring basin.
[0012] In one embodiment of this application, the preparation of molten iron includes the following steps: Two of the three 12.5-ton electric furnaces each melt 12.5 tons of molten iron; The molten iron in one of the 12.5-ton electric furnaces was poured into a 13-ton ladle and kept at a constant temperature. The remaining two 12.5-ton electric furnaces each melted 12.5 tons of molten iron; The molten iron in the three 12.5-ton electric furnaces was adjusted to the process composition, and the molten iron from one of the 12.5-ton electric furnaces was poured into another 13-ton ladle. The molten iron from the first 13-ton ladle is poured into an empty 12.5-ton electric furnace to raise the temperature and adjust the composition. The 12.5 tons of molten iron from the first 12.5-ton electric furnace is poured into the first 25-ton ladle for spheroidization treatment, and then the molten iron from the second 13-ton ladle is poured into this 25-ton ladle. The 12.5 tons of molten iron from the second electric furnace are poured into the second 25-ton ladle for spheroidization, and then the 12.5 tons of molten iron from the third electric furnace are poured into the second 25-ton ladle.
[0013] In one embodiment of this application, before all the molten iron in a 12.5-ton electric furnace is poured into a 13-ton ladle, the temperature of the molten iron is raised to any value between 1510°C and 1520°C; after the molten iron is poured in, an insulating covering agent is laid on the surface of the molten iron for heat preservation.
[0014] In one embodiment of this application, during the molten iron pouring step, the inoculant is continuously added to the pouring basin by the inoculation bucket during the molten iron pouring process.
[0015] The beneficial effects of the large ductile iron casting equipment and molten iron preparation method according to the embodiments of this application are as follows: By employing a multi-stage pouring method, the foundry's existing casting equipment and molten iron preparation methods, which typically have a capacity of a few dozen tons, can now produce castings with a weight exceeding 50 tons. This reduces casting costs and allows for the production of large castings without requiring upgrades to the existing plant. Furthermore, the multi-layered pouring basins eliminate the need for filters and prevent primary slag from entering the casting cavity.
[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0017] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the structure of a molten iron casting apparatus according to an embodiment of this application; Figure 2 This is a process flow diagram of a method for preparing molten iron according to an embodiment of this application; Figure 3 This is a process flow diagram of a molten iron pouring method according to an embodiment of this application.
[0018] As shown in the figure: 1. Sand mold; 20. First pouring basin; 21. Second pouring basin; 3. Plugging rod; 4. Inoculation bucket. Detailed Implementation
[0019] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.
[0020] The following description, in conjunction with the accompanying drawings, describes a large ductile iron casting equipment for pouring molten iron parts according to an embodiment of this application.
[0021] like Figures 1-3 As shown, the large ductile iron casting equipment of this application embodiment includes a sand mold 1, a multi-layer pouring basin, a plug rod 3, and an inoculation hopper 4.
[0022] The sand mold 1 has a gating channel, and multiple gating basins are set on the sand mold 1. Each gating basin is interconnected, and the plug rod 3 and the incubation hopper 4 are set on the upper gating basin.
[0023] It should be noted that the stopper rod 3 described in this embodiment can control the flow rate of molten iron. That is, the diameter of the stopper rod 3 increases from the bottom to the top, and the maximum diameter is the same as the pouring diameter of the pouring basin. When relevant personnel control the flow rate of molten iron, they can raise the stopper rod 3 to different heights.
[0024] It should be noted that the multi-layer gating basin described in this embodiment is set to at least two. By setting up the multi-layer gating basin, it is ensured that primary slag does not enter the mold cavity, and a filter screen is not required, and primary slag will not enter the casting.
[0025] Specifically, during the actual operation, the relevant staff pulled out the plug rod 3, and the molten iron flowed from the upper pouring basin to the lower pouring basin, and then entered the sand mold 1 through the gating channel. During this process, the inoculant hopper 4 evenly discharged the inoculant, and the molten iron cooled in the sand mold 1 to complete the casting of the sand mold 1.
[0026] In one embodiment of this application, such as Figure 1 As shown, the multi-layer gating basin includes a first gating basin 20 and a second gating basin 21.
[0027] The first pouring basin 20 is set on the sand mold 1 and connected to the gating system of the sand mold 1. The second pouring basin 21 is connected to the first pouring basin 20. The plug rod 3 is inserted into the gating system of the second pouring basin 21. The incubation hopper 4 is set on the second pouring basin 21.
[0028] It should be noted that the inoculation bucket 4 described in this embodiment is a common component in the casting industry and is existing technology, so it will not be described in detail here.
[0029] In one embodiment of this application, such as Figure 1-3As shown, the method for preparing molten iron for large ductile iron castings includes the following steps: S01 molten iron preparation: Three 12.5-ton electric furnaces and two 13-ton ladles are used for multiple batches of melting and composition adjustment. The molten iron is then collected into two 25-ton ladles through batch spheroidization treatment. S02 molten iron pouring: One 25-ton ladle of molten iron is lifted by a crane to the upper pouring basin to pour the molten iron, and then another 25-ton ladle of molten iron is lifted by a crane to the top of the upper pouring basin. When the plug rod is opened, the molten iron in the upper pouring basin (or the second pouring basin 20) flows into the gating channel of the sand mold 1 through the lower pouring basin (or the first pouring basin 21), and at the same time, the molten iron in another 25-ton ladle is added to the upper pouring basin.
[0030] It should be noted that the method described in this embodiment is applicable to castings weighing 50 tons, and the same method can be applied to castings weighing more than 50 tons.
[0031] In one embodiment of this application, such as Figure 2 The flowchart shown illustrates the process of molten iron preparation, which includes the following steps: S011: Two of the three 12.5-ton electric furnaces each melt 12.5 tons of molten iron; S012: All the molten iron in one of the 12.5-ton electric furnaces is poured into a 13-ton ladle and kept at a constant temperature; S013: The remaining two 12.5-ton electric furnaces will each melt 12.5 tons of molten iron; S014: The molten iron in the three 12.5-ton electric furnaces is adjusted to the process composition, and the molten iron from one of the 12.5-ton electric furnaces is poured into another 13-ton ladle. S015: Pour the molten iron from the first 13-ton ladle into one of the empty 12.5-ton electric furnaces to raise the temperature and adjust the composition; S016: The 12.5 tons of molten iron from the first 12.5-ton electric furnace is poured into the first 25-ton ladle for spheroidization treatment, and then the molten iron from the second 13-ton ladle is poured into this 25-ton ladle. S017: 12.5 tons of molten iron from the second electric furnace are poured into the second 25-ton ladle for spheroidization treatment, and then 12.5 tons of molten iron from the third electric furnace are poured into the second 25-ton ladle.
[0032] Specifically, the three 12.5-ton electric furnaces can be divided into the first electric furnace, the second electric furnace, and the third electric furnace; the two 13-ton molten iron ladles can be divided into the first 13-ton molten iron ladle and the second 13-ton molten iron ladle; and the two 25-ton molten iron ladles can be divided into the first 25-ton molten iron ladle and the second 25-ton molten iron ladle.
[0033] S011: During operation, the first and second electric furnaces each melt 12.5 tons of molten iron, while the third electric furnace is idle.
[0034] S012: All the molten iron in the first electric furnace is poured into the first 13-ton ladle and kept warm. At this time, the first electric furnace is empty. In addition, the molten iron in the first electric furnace is heated to 1510℃-1520℃ before being poured in, and then a heat-insulating covering agent is used to keep the surface of the molten iron warm after pouring.
[0035] S013: The first and third electric furnaces each melt 12.5 tons of molten iron, at which point all three furnaces have 12.5 tons of molten iron. S014: The molten iron in the three electric furnaces is adjusted according to the process composition (the specific adjustment is based on existing technology and will not be described in detail here). The molten iron from the third electric furnace is poured into the second 13-ton ladle. At this time, the third electric furnace is empty, while the first and second 13-ton ladles both contain molten iron.
[0036] S015: Pour the molten iron from the first 13-ton ladle into the empty third 12.5-ton electric furnace for heating and composition adjustment. At this time, the first 13-ton ladle is empty, and all three electric furnaces contain molten iron.
[0037] S016: 12.5 tons of molten iron from the first 12.5-ton electric furnace is poured into the first 25-ton ladle for spheroidization. Then, molten iron from the second 13-ton ladle is poured into the 25-ton ladle. At this time, the first electric furnace is empty, the second 13-ton ladle is empty, the second 25-ton ladle is empty, and the second and third electric furnaces and the first 13-ton ladle all contain molten iron.
[0038] S017: 12.5 tons of molten iron from the second electric furnace are poured into the second 25-ton ladle for spheroidization treatment. Then, 12.5 tons of molten iron from the third electric furnace are poured into the second 25-ton ladle. At this time, all three electric furnaces and the two 13-ton ladles are empty, and the two 25-ton ladles are fully loaded with spheroidized molten iron. Slag removal is then performed on the two 25-ton ladles. After slag removal, the process proceeds to the next casting step.
[0039] S02: During pouring (e.g.) Figure 3 (The diagram shows the molten iron pouring process). After the first 25-ton ladle of molten iron is lifted by a crane to the upper pouring basin and poured out, the crane lifts the second 25-ton ladle of molten iron to the top of the upper pouring basin.
[0040] When the plug rod 3 is opened, the molten iron in the upper pouring basin leaks out through the lower pouring basin into the gating channel of the sand mold 1, and the molten iron in the second 25-ton ladle leaks out into the upper pouring basin.
[0041] During the molten iron pouring process, the inoculant hopper 4 continuously adds inoculant to the pouring basin along with the molten iron pouring process.
[0042] The molten iron cooled and solidified in sand mold 1, completing the pouring of a 50-ton casting.
[0043] In one embodiment of this application, such as Figure 2 As shown, the spheroidizing process involves taking half (12.5 tons) of molten iron for spheroidizing treatment, and then pouring the other half (12.5 tons) of molten iron directly into the ladle containing the spheroidized molten iron.
[0044] Understandably, by using the above-mentioned spheroidizing process—that is, first spheroidizing 12.5 tons of molten iron, and then mixing the remaining 12.5 tons of unspheroidized molten iron with the spheroidized molten iron—compared to spheroidizing 25 tons of molten iron at once, this process results in a milder spheroidizing reaction, higher operational safety, reduced oxidation and burn-off of spheroidizing elements, increased absorption rate of spheroidizing agent, smaller overall temperature drop of molten iron, better protection of casting temperature, and strong turbulent stirring during the mixing process, which improves the uniformity of molten iron composition and spheroidizing elements. It can also adapt to the equipment capacity limitations of large-tonnage spheroidizing treatment and optimize the problems of violent reaction and uneven composition that are prone to occur in one-time spheroidizing of large-tonnage molten iron.
[0045] In summary, the large ductile iron casting equipment and molten iron preparation method of this application adopt a multi-distribution method, which enables foundries with existing casting equipment and molten iron preparation methods of more than ten tons to produce castings with a weight of more than 50 tons, thereby reducing casting costs.
[0046] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0048] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. A large-scale ductile iron casting equipment, characterized in that, Includes sand molds, multi-layer gating bowls, plug rods, and inoculation hoppers, among which, The sand mold is provided with a gating channel; The multiple layers of gating basins are respectively arranged on the sand mold, and the gating basins of each layer are interconnected; The plug rod and the inoculation hopper are mounted on the upper pouring basin.
2. The large ductile iron casting equipment according to claim 1, characterized in that, The multi-layered gating system includes a first gating system and a second gating system, wherein, The first pouring bowl is disposed on the sand mold and communicates with the gating system of the sand mold; The second gating bowl is stacked on top of the first gating bowl; The plug rod is inserted into the gate of the second gating bowl; The incubation hopper is installed on the second pouring basin.
3. The large ductile iron casting equipment according to claim 1, characterized in that, The diameter of the plug rod increases from bottom to top, and the maximum diameter of the plug rod is adapted to the gate diameter of the second gate basin.
4. A method for preparing molten iron for large ductile iron castings, characterized in that, The large ductile iron casting equipment according to any one of claims 1-3 includes an iron preparation step and an iron casting step. Iron preparation: Three 12.5-ton electric furnaces and two 13-ton ladles are used for multiple batches of melting and composition adjustment. The molten iron is then collected into two 25-ton ladles through batch spheroidization treatment. Iron pouring: One 25-ton ladle of molten iron is lifted by a crane to the upper pouring basin to pour the molten iron, and then another 25-ton ladle of molten iron is lifted by a crane to the top of the upper pouring basin. Open the plug rod, and the molten iron in the upper pouring basin flows into the sand mold's gating channel through the lower pouring basin. At the same time, molten iron from another 25-ton ladle is added to the upper pouring basin.
5. The method for preparing molten iron for large ductile iron castings according to claim 4, characterized in that, The preparation of molten iron includes the following steps: Two of the three 12.5-ton electric furnaces each melt 12.5 tons of molten iron; The molten iron in one of the 12.5-ton electric furnaces was poured into a 13-ton ladle and kept at a constant temperature. The remaining two 12.5-ton electric furnaces each melted 12.5 tons of molten iron; The molten iron in the three 12.5-ton electric furnaces was adjusted to the process composition, and the molten iron from one of the 12.5-ton electric furnaces was poured into another 13-ton ladle. The molten iron from the first 13-ton ladle is poured into an empty 12.5-ton electric furnace to raise the temperature and adjust the composition. The 12.5 tons of molten iron from the first 12.5-ton electric furnace is poured into the first 25-ton ladle for spheroidization treatment, and then the molten iron from the second 13-ton ladle is poured into this 25-ton ladle. The 12.5 tons of molten iron from the second electric furnace are poured into the second 25-ton ladle for spheroidization, and then the 12.5 tons of molten iron from the third electric furnace are poured into the second 25-ton ladle.
6. The method for preparing molten iron for large ductile iron castings according to claim 5, characterized in that, Before pouring all the molten iron from a 12.5-ton electric furnace into a 13-ton ladle, the temperature of the molten iron is raised to any value between 1510℃ and 1520℃; after the molten iron is poured in, an insulating covering is laid on the surface of the molten iron for heat preservation.
7. The method for preparing molten iron for large ductile iron castings according to claim 4, characterized in that, In the molten iron pouring step, the inoculation hopper continuously adds inoculant to the pouring basin during the molten iron pouring process.