Filtering-free pouring system and pouring process for low-slag-inclusion wind power ductile iron casting

Abstract

The invention discloses a filtering-free pouring system and pouring process for a low slag inclusion wind power ductile iron casting, the pouring system comprises a pouring cup, a sprue, a sprue nest, a drainage cross gate, an annular cross gate, a gap bridge, a tail end cross gate and an ingate, the pouring cup is used for blocking primary slag in molten iron to prevent the primary slag from entering the sprue; the drainage cross gate is used for reducing the flow speed of the molten iron input by the sprue and playing a role in stabilizing a flow field and scum, the annular cross gate is used for carrying out secondary scum blocking on the molten iron and uniformly draining the molten iron to the gap bridge, and the tail end cross gate is used for introducing the molten iron input by the gap bridge into the ingate. According to the structure, primary slag in molten iron is blocked through the pouring cup and the annular transverse pouring gate, the flow speed of the molten iron in the transverse pouring gate and the inner pouring gate is controlled through the reasonable section ratio of a pouring system, a large amount of secondary slag is prevented from being formed, and then a wind power ductile iron casting with the low slag inclusion amount is produced.

Description

Technical Field

[0001] The invention relates to a non-filtering pouring system and a pouring process for a low-slag wind power ductile iron casting, belonging to the technical field of casting process. Background Art

[0002] In the production process of ductile iron castings, there is a process of spheroidizing and inoculating the original molten iron. After the spheroidizing elements magnesium and rare earth are added to the molten iron, they will react with the sulfur and oxygen in the molten iron to form sulfides, oxides, magnesium silicate or complex sulfur-oxygen compounds containing magnesium and rare earth, thereby producing a large amount of slag. In addition, the spheroidizing elements will continuously react with sulfur and oxygen elements to form secondary slag during the subsequent molten iron transportation and pouring process. The working environment of wind power ductile iron castings is complex. In addition to sufficient strength and plasticity, they must also have sufficient low-temperature impact toughness. During the pouring process of wind power ductile iron castings, when the slag in the molten iron cannot be completely removed and enters the casting mold or a large amount of secondary slag is formed due to the unreasonable structure of the pouring system, the mechanical properties of wind power ductile iron castings, especially the impact toughness, will be greatly reduced, thereby reducing the service life of the casting products, and even directly leading to the scrapping of the castings.

[0003] In order to reduce the slag inclusion defects of wind power ductile iron castings, filters are traditionally installed in the pouring system to prevent the primary slag in the molten iron from entering the casting cavity. At the same time, the generation of secondary slag is reduced due to the reduced molten iron flow rate and stable flow field. However, wind power ductile iron castings are generally large in tonnage and take a long time to pour, and the filter has the risk of overload softening and breakage. The use of filter plates will also produce a cast iron filter chamber containing filter plates. Directly smelting them as recycled materials will result in excessive slag content in the molten iron, increasing the workload of slag removal before the furnace. In addition, the filter plates themselves are relatively expensive.

[0004] In view of this, it is necessary to provide a low-slag wind power ductile iron casting filterless casting system and casting process which has good slag blocking effect and can reduce the generation of secondary slag. Summary of the invention

[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides a filter-free pouring system and a pouring process for low-slag wind power ductile iron castings, thereby solving the above-mentioned technical problems.

[0006] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is: a filterless pouring system for low-slag wind power ductile iron castings, the pouring system comprising a pouring cup, a sprue, a sprue nest, a drainage runner, a ring runner, a bridge, an end runner, and an ingrown; one side of the pouring cup is connected to the sprue; one end of the sprue is connected to the sprue nest; the side of the sprue nest is connected with a plurality of drainage runners; one side of the drainage runner is connected to the ring runner; a plurality of bridges are connected around the ring runner; one side of the bridge is connected with the end runner; the pouring cup is used to intercept the primary slag in the molten iron to prevent it from entering the sprue, the drainage runner is used to reduce the flow rate of the molten iron input by the sprue and play a role in stabilizing the flow field and slag, the ring runner is used to block the slag for the second time and drain the molten iron evenly to the bridge, and the end runner is used to introduce the molten iron input by the bridge into the ingrown.

[0007] Furthermore, the pouring cup includes a molten iron injection chamber, a molten iron outlet chamber, a gate groove, an iron plate and a drainage straight runner; a refractory gate is arranged in the gate groove to separate the molten iron injection chamber and the upper half of the molten iron outlet chamber; the iron plate is placed at the bottom of the molten iron outlet chamber and separates the molten iron outlet chamber from the drainage straight runner.

[0008] Furthermore, the height difference between the bottom surface of the molten iron outlet chamber and the bottom surface of the molten iron injection chamber is 5-6 times the diameter of the drainage straight runner, and the thickness of the iron plate placed at the bottom of the molten iron outlet chamber is 5-8mm.

[0009] Furthermore, the water inlet of the sprue is connected to the drainage sprue, the diameter of the sprue is slightly smaller than the diameter of the drainage sprue, the water outlet of the sprue is connected to the sprue nest by bottom reversal, and the diameter of the sprue nest is 2-4 times the diameter of the sprue.

[0010] Furthermore, the ratio of the cross-sectional height to the width of the drainage runner is not less than 1.5, and the drainage runner is arranged to be an arc with a length of not less than 200 mm, with 2-4 runners, and the two ends are respectively connected to the sprue nest and the annular runner.

[0011] Furthermore, the cross section of the bridge is wide and thin flat with a thickness of 10-15 mm. The bridge is connected to the lower part of the annular runner and the upper part of the terminal runner. The height ratio of the annular runner to the bridge is greater than 5.

[0012] Furthermore, the cross-sectional dimensions of the annular runner and the terminal runner are the same as those of the drainage runner, and the cross-sectional dimensions of the terminal runner and the cross-sectional dimensions of the annular runner are inverted in the up and down directions. The drainage runner and the annular runner are mainly located above the parting surface of the casting, and the terminal runner and the bridge are mainly located below the parting surface of the casting.

[0013] Furthermore, the water inlet of the ingrate is introduced from the bottom of the terminal runner, and the water outlet is connected to the casting cavity through the bottom reverse.

[0014] Furthermore, the sprue nest, drainage runner, annular runner, bridge, terminal runner and ingates are all located at the bottom of the casting cavity. The total cross-sectional dimensions of the sprue, drainage runner, bridge and ingates are in a ratio of 1:3-5:3-5:4-6.

[0015] A casting process of a non-filtered casting system for low-slag wind power ductile iron castings, comprising the following steps: step 1: after the casting sand mold is assembled, a sand box corresponding to a pouring cup is bonded to the casting sand mold using a casting adhesive, so that the drainage sprue of the pouring cup is connected to the sprue, and an iron plate is placed at the bottom of the molten iron outlet chamber of the pouring cup; Step 2: Use an electric furnace to melt ductile iron molten iron according to the composition requirements, and quickly heat the molten iron to 1520-1540°C after the composition is qualified, then cut off the power and let the molten iron stand for 5-8 minutes. During the standing period, repeatedly sprinkle the slag remover into the molten iron and remove the slag; Step 3: After the standing period, pour the molten iron into the ladle according to the pouring weight requirement, use the wire feeding method to spheroidize and inoculate the molten iron, and then sprinkle the slag remover again and remove the slag; Step 4: Transfer the spheroidizing inoculated ladle to the casting sand mold, measure the temperature of the molten iron and place slag-blocking cotton at the ladle mouth, pour at 1350-1380℃, then quickly pour the molten iron into the molten iron injection chamber within 15-20s until the molten iron in the pouring cup is nearly full. When the molten iron level in the pouring cup begins to drop, continue to pour molten iron into the molten iron injection chamber and keep the molten iron level in the pouring cup always in a nearly full state. Stop pouring when the weight of the poured molten iron reaches the expected weight. During the process of pouring the molten iron from the ladle to the molten iron injection chamber, perform flow inoculation on the molten iron to improve the inoculation effect and prevent inoculation decline.

[0016] The beneficial effects of the present invention are as follows: when pouring starts, the pouring cup is quickly filled, and the slag in the molten iron in the pouring cup can float to the surface; then the iron plate in the pouring cup melts, so that the pouring cup is connected to the sprue, and clean molten iron then enters the sprue. The pouring cup maintains the depth of the molten iron in the pouring cup because it is replenished with subsequent molten iron at the same time; the primary slag in the molten iron that has not been cleaned off always floats on the upper surface of the molten iron in the pouring cup during the pouring process.

[0017] The sprue nest, drainage runner, annular runner, bridge, end runner and ingates are all located at the bottom of the casting and can be filled quickly, thus avoiding the phenomenon of molten iron entrainment.

[0018] The cross section of the annular runner is high and narrow, and the cross section of the aisle piece is wide and thin. This structural form can retain the slag that enters the pouring system due to the incomplete retention of the pouring cup in the runner, so that the molten iron can be purified twice.

[0019] The cross-sectional dimensions of the sprue, drainage runner, aisle plate and ingates gradually increase, forming a completely open pouring system. The flow rate of molten iron in the pouring system is gradually reduced to achieve low-speed and stable filling, prevent molten iron turbulence and splashing, and reduce the formation of secondary slag.

[0020] The wind power ductile iron casting system can be used to replace the traditional casting system for placing filter plates, thereby saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a non-filtered pouring system for low-slag wind power ductile iron castings of the present invention; Figure 2 For the present invention Figure 1 A top view of the gating system; Figure 3 For the present invention Figure 1 Schematic diagram of the pouring cup in the pouring system; Figure 4 For the present invention Figure 2 Middle AA section view; Figure 5 A three-dimensional diagram of the casting process of a wind power ductile iron casting bearing seat according to an embodiment of the present invention; Figure 6 Another perspective of the casting process of the wind power ductile iron casting bearing seat according to the embodiment of the present invention; Figure 7 It is a three-dimensional diagram of the casting process of the main shaft of the wind power ductile iron casting according to an embodiment of the present invention; Figure 8 This is another perspective of the casting process of the main shaft of the wind power ductile iron casting according to the embodiment of the present invention.

[0022] In the figure: 1. pouring cup; 101. molten iron injection chamber; 102. molten iron outlet chamber; 103. gate groove; 104. iron plate; 105. drainage sprue; 2. sprue; 3. sprue nest; 4. drainage runner; 5. annular runner; 6. bridge; 7. end runner; 8. inner runner; 9. wind power ductile iron casting bearing seat; 10. wind power ductile iron casting main shaft. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below through the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. Example

[0025] refer to Figures 1 to 6 The present embodiment relates to a filter-free pouring system for a low-slag wind power ductile iron casting bearing seat, the pouring system comprising: a pouring cup 1, a sprue 2, a sprue nest 3, a drainage runner 4, a ring runner 5, a bridge 6, an end runner 7, and an inner runner 8.

[0026] The pouring cup 1 includes a molten iron injection chamber 101, a molten iron outlet chamber 102, a gate groove 103, an iron plate 104 and a drainage sprue 105. A refractory gate is arranged in the gate groove 103 to separate the molten iron injection chamber 101 from the upper half of the molten iron outlet chamber 102, and an iron plate with a thickness of 6 mm is placed at the bottom of the molten iron outlet chamber 102 to separate the molten iron outlet chamber 102 from the drainage sprue 105. The molten iron outlet chamber 102 is deeper than the molten iron injection chamber 101, and the height difference from the bottom surface of the molten iron outlet chamber 102 to the bottom surface of the molten iron injection chamber 101 is 5-6 times the diameter of the drainage sprue 105. When the pouring cup is used to pour the ductile iron casting bearing seat, the pouring cup is first filled quickly, and the slag in the molten iron in the pouring cup can float to the surface. Then the iron plate in the pouring cup melts, so that the pouring cup is connected to the sprue, and clean molten iron begins to enter the sprue. Then, molten iron continues to be poured into the molten iron injection chamber 101 of the pouring cup to maintain the depth of the molten iron in the pouring cup. The primary slag that has not been scraped off from the molten iron always floats on the upper surface of the molten iron in the pouring cup to prevent the slag from entering the sprue.

[0027] The water inlet of the sprue 2 is connected to the drainage sprue 105, and its diameter is slightly smaller than the drainage sprue 105, which is conducive to filling the sprue and reducing the air intake of the sprue. The water outlet of the sprue 2 is connected to the sprue nest 3 by bottom reversal. The diameter of the sprue nest 3 is 4 times the diameter of the sprue 2, which is conducive to slowing down the molten iron.

[0028] The sprue nest 3 is connected to three arc-shaped drainage runners 4, which are used to further reduce the flow rate of the molten iron input by the sprue 2 and play a role in stabilizing the flow field. The length of the drainage runner 4 is not less than 200 mm, the ratio of the cross-sectional height to the width is 1.5, and it is high and narrow. The end is connected to the annular runner 5, which is conducive to the slag inclusion in the molten iron floating and stored on the upper surface of the annular runner 5. The cross-sectional size of the annular runner 5 is the same as that of the drainage runner 4.

[0029] Six flat bridges 6 with wide and thin cross-sections are connected to the bottom of the annular runner 5, with a thickness of 12 mm. The height ratio of the annular runner 5 to the bridge 6 is greater than 5, so as to increase the height difference between the slag on the upper part of the molten iron in the annular runner 5 and the bridge 6, avoid the slag adsorption area of ​​the bridge 6, and play a further slag blocking role.

[0030] The ends of the bridge 6 are connected to 6 groups of terminal runners 7. The cross-sectional dimensions of the terminal runners 7 are the same as those of the drainage runners 4 and the annular runners 5, and the cross-sectional dimensions are opposite to those of the end runners 7 in the vertical direction, that is, the cross-sectional dimensions of the terminal runners 7 and the annular runners 5 are inverted in the vertical direction. The terminal runners 7 are used to connect the bridge 6 and the ingates 8, and at the same time, they further reduce the flow rate of the molten iron and stabilize the flow field to reduce the formation of secondary slag.

[0031] Fifteen ingates 8 are introduced at the bottom of the terminal cross runner 7, and the ends of the ingates 8 are connected to the sand mold cavity of the casting in the form of a bottom reversal.

[0032] During pouring, the molten iron flows in the following order: pouring cup 1, sprue 2, sprue nest 3, drainage runner 4, annular runner 5, bridge 6, end runner 7, inner runner 8, and finally enters the sand mold cavity of the casting.

[0033] In this embodiment, the sprue nest 3, the drainage runner 4, the annular runner 5, the bridge 6, the terminal runner 7, and the ingrate 8 are all arranged at the bottom of the casting sand mold cavity. When filling the mold, the pouring system is quickly filled with molten iron, which is conducive to the floating slag in the molten iron and avoids the occurrence of air entrainment in the pouring system. The total cross-sectional size ratio of the sprue 2, the drainage runner 4, the bridge 6, and the ingrate 8 is 1:4:4.5:6, which is a completely open pouring system. The speed of the molten iron gradually slows down during the flow from the sprue to the ingrate, so that the slag has enough time to float in the pouring system, and at the same time, it prevents the molten iron from splashing and entraining during filling, reduces the oxidation of the molten iron during filling, and reduces the generation of secondary slag.

[0034] When the pouring system provided in this embodiment 1 is used to pour the wind power ductile iron casting bearing seat, the specific pouring method steps are as follows: Step 1: Use the pouring system in this embodiment to prepare a casting sand mold. After the casting sand mold is assembled, use a casting adhesive to stick the sand box corresponding to the pouring cup 1 and the casting sand mold together, so that the drainage straight runner 105 of the pouring cup 1 is connected with the straight runner 2, and place an iron plate 104 at the bottom of the molten iron outlet chamber 102 of the pouring cup 1.

[0035] Step 2: Use an electric furnace to melt the ductile iron raw iron according to the composition requirements. After the composition is qualified, the raw iron is quickly heated to 1520~1540℃, and then the power is turned off and the molten iron is allowed to stand for 5~8 minutes. During the standing period, the slag remover is repeatedly sprinkled into the molten iron and the slag is removed.

[0036] Step 3: After standing, pour the molten iron into the ladle according to the pouring weight requirement, use the wire feeding method to spheroidize the molten iron, and then sprinkle the slag remover again and beat the slag.

[0037] Step 4: Transfer the molten iron ladle after spheroidizing inoculation treatment to the casting sand mold, measure the temperature of the molten iron, place slag-blocking cotton at the ladle mouth of the molten iron ladle, and pour at a temperature of 1350-1380°C. First, quickly pour the molten iron into the molten iron injection chamber 101 within a time range of 15-20s until the molten iron in the pouring cup 1 is nearly full. When the molten iron level in the pouring cup 1 begins to drop, continue to pour molten iron into the molten iron injection chamber 101 and keep the molten iron level in the pouring cup 1 always in a nearly full state. Stop pouring when the weight of the poured molten iron reaches the expected weight. During the pouring process, the molten iron is inoculated with the flow to improve the inoculation effect and prevent inoculation decline. Example

[0038] refer to Figure 1-5 and Figure 7-8 The present embodiment relates to a filter-free pouring system for a main shaft of a low-slag wind power ductile iron casting, the pouring system comprising: a pouring cup 1, a sprue 2, a sprue nest 3, a drainage runner 4, a ring runner 5, a bridge 6, an end runner 7, and an inner runner 8.

[0039] The pouring cup 1 includes a molten iron injection chamber 101, a molten iron outlet chamber 102, a gate groove 103, an iron plate 104 and a drainage sprue 105. A refractory gate is arranged in the gate groove 103 to separate the molten iron injection chamber 101 from the upper half of the molten iron outlet chamber 102, and an iron plate with a thickness of 6 mm is placed at the bottom of the molten iron outlet chamber 102 to separate the molten iron outlet chamber 102 from the drainage sprue 105. The molten iron outlet chamber 102 is deeper than the molten iron injection chamber 101, and the height difference from the bottom surface of the molten iron outlet chamber 102 to the bottom surface of the molten iron injection chamber 101 is 5 to 6 times the diameter of the drainage sprue 105. When the pouring cup is used to pour the ductile iron casting bearing seat, the pouring cup is first filled quickly, and the slag in the molten iron in the pouring cup can float to the surface. Then the iron plate in the pouring cup melts, so that the pouring cup is connected to the sprue, and clean molten iron begins to enter the sprue. Then, molten iron continues to be poured into the molten iron injection chamber 101 of the pouring cup to maintain the depth of the molten iron in the pouring cup. The primary slag that has not been scraped off from the molten iron always floats on the upper surface of the molten iron in the pouring cup to prevent the slag from entering the sprue.

[0040] The water inlet of the sprue 2 is connected to the drainage sprue 105, and its diameter is slightly smaller than the drainage sprue 105, which is conducive to filling the sprue and reducing the air intake of the sprue. The water outlet of the sprue 2 is connected to the sprue nest 3 by bottom reversal. The diameter of the sprue nest 3 is 3 times the diameter of the sprue 2, which is conducive to slowing down the molten iron.

[0041] The sprue nest 3 is connected to three arc-shaped drainage runners 4, which are used to further reduce the flow rate of the molten iron input by the sprue 2 and play a role in stabilizing the flow field. The length of the drainage runner 4 is not less than 200 mm, the ratio of the cross-sectional height to the width is 1.5, and it is high and narrow. The end is connected to the annular runner 5, which is conducive to the slag inclusion in the molten iron floating and stored on the upper surface of the annular runner 5. The cross-sectional size of the annular runner 5 is the same as that of the drainage runner 4.

[0042] Six flat bridges 6 with wide and thin cross-sections are connected to the bottom of the annular runner 5, with a thickness of 15 mm. The height ratio of the annular runner 5 to the bridge 6 is greater than 5, so as to increase the height difference between the slag on the upper part of the molten iron in the annular runner 5 and the bridge 6, avoid the slag adsorption area of ​​the bridge 6, and play a further slag blocking role.

[0043] The ends of the bridge 6 are connected to 6 groups of terminal runners 7. The cross-sectional dimensions of the terminal runners 7 are the same as those of the drainage runners 4 and the annular runners 5, and the cross-sectional dimensions are opposite to those of the end runners 7 in the vertical direction, that is, the cross-sectional dimensions of the terminal runners 7 and the annular runners 5 are inverted in the vertical direction. The terminal runners 7 are used to connect the bridge 6 and the ingates 8, and at the same time, they further reduce the flow rate of the molten iron and stabilize the flow field to reduce the formation of secondary slag.

[0044] Twelve ingates 8 are introduced at the bottom of the terminal cross runner 7, and the ends of the ingates 8 are connected to the sand mold cavity of the casting in the form of a bottom reversal.

[0045] During pouring, the molten iron flows in the following order: pouring cup 1, sprue 2, sprue nest 3, drainage runner 4, annular runner 5, bridge 6, end runner 7, inner runner 8, and finally enters the sand mold cavity of the casting.

[0046] Furthermore, the sprue nest 3, the drainage runner 4, the annular runner 5, the bridge 6, the terminal runner 7, and the ingrate 8 are all arranged at the bottom of the casting sand mold cavity. When filling the mold, the pouring system is quickly filled with molten iron, which is conducive to the floating slag in the molten iron and avoids the occurrence of air entrainment in the pouring system. The total cross-sectional size ratio of the sprue 2, the drainage runner 4, the bridge 6, and the ingrate 8 is 1:3.5:4.5:5.5, which is a completely open pouring system. The speed of the molten iron gradually slows down during the flow from the sprue to the ingrate, so that the slag has enough time to float in the pouring system, and at the same time, it prevents the molten iron from splashing and entraining during filling, reduces the oxidation of the molten iron during filling, and reduces the generation of secondary slag.

[0047] When the pouring system provided in this embodiment is used to pour the main shaft of the wind power ductile iron casting, the specific pouring method steps are as follows: Step 1: Use the pouring system in this embodiment to prepare a casting sand mold. After the casting sand mold is assembled, use a casting adhesive to stick the sand box corresponding to the pouring cup 1 and the casting sand mold together, so that the drainage straight runner 105 of the pouring cup 1 is connected with the straight runner 2, and place an iron plate 104 at the bottom of the molten iron outlet chamber 102 of the pouring cup 1.

[0048] Step 2: Use an electric furnace to melt the ductile iron raw iron according to the composition requirements. After the composition is qualified, the raw iron is quickly heated to 1520-1540℃, and then the power is turned off and the molten iron is allowed to stand for 5-8 minutes. During the standing period, the slag remover is repeatedly sprinkled into the molten iron and the slag is removed.

[0049] Step 3: After standing, pour the molten iron into the ladle according to the pouring weight requirement, use the wire feeding method to spheroidize the molten iron, and then sprinkle the slag remover again and beat the slag.

[0050] Step 4: Transfer the molten iron ladle after the spheroidizing inoculation treatment to the casting sand mold, measure the temperature of the molten iron, place slag-blocking cotton at the ladle mouth of the molten iron ladle, and pour at a temperature of 1350-1380°C. First, quickly pour the molten iron into the molten iron injection chamber 101 within a time range of 15-20s until the molten iron in the pouring cup 1 is nearly full. When the molten iron level in the pouring cup 1 begins to drop, continue to pour molten iron into the molten iron injection chamber 101 and keep the molten iron level in the pouring cup 1 always in a nearly full state. Stop pouring when the weight of the poured molten iron reaches the expected weight. During the pouring process, the molten iron is inoculated with the flow to improve the inoculation effect and prevent inoculation decline.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A filter-free pouring system for low-slag wind power ductile iron castings, characterized in that: The pouring system comprises a pouring cup (1), a sprue (2), a sprue nest (3), a drainage runner (4), an annular runner (5), a bridge (6), an end runner (7), and an inner runner (8); one side of the pouring cup (1) is connected to the sprue (2); one end of the sprue (2) is connected to the sprue nest (3); a side of the sprue nest (3) is connected to a plurality of drainage runners (4); one side of the drainage runner (4) is connected to the annular runner (5); and the annular runner (5) is connected to the inner runner (8). There are a plurality of bridges (6); one side of the bridge (6) is connected to a terminal runner (7); the pouring cup (1) is used to intercept the primary slag in the molten iron to prevent it from entering the sprue (2); the drainage runner (4) is used to reduce the flow rate of the molten iron input from the sprue (2) and play a role in stabilizing the flow field and slag; the annular runner (5) is used to block the slag of the molten iron for the second time and drain the molten iron evenly to the bridge (6); the terminal runner (7) is used to guide the molten iron input from the bridge (6) into the inner runner (8).

2. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The pouring cup (1) comprises a molten iron injection chamber (101), a molten iron outlet chamber (102), a gate groove (103), an iron plate (104) and a drainage sprue (105); a refractory gate is arranged in the gate groove (103) to separate the molten iron injection chamber (101) from the upper part of the molten iron outlet chamber (102); the iron plate (104) is placed at the bottom of the molten iron outlet chamber (102) and separates the molten iron outlet chamber (102) from the drainage sprue (105).

3. A filter-free pouring system for low-slag wind power ductile iron castings according to claim 2, characterized in that: The height difference between the bottom surface of the molten iron outlet chamber (102) and the bottom surface of the molten iron injection chamber (101) is 5-6 times the diameter of the drainage sprue (105), and the thickness of the iron plate (104) placed at the bottom of the molten iron outlet chamber (102) is 5-8 mm.

4. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The water inlet of the sprue (2) is connected to the drainage sprue (105), the diameter of the sprue (2) is slightly smaller than the diameter of the drainage sprue (105), the water outlet of the sprue (2) is connected to the sprue nest (3) by bottom reversal, and the diameter of the sprue nest (3) is 2-4 times the diameter of the sprue (2).

5. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The ratio of the cross-sectional height to the width of the drainage runner (4) is not less than 1.

5. The drainage runner (4) is configured to be an arc with a length of not less than 200 mm, with 2 to 4 runners in number, and the two ends are respectively connected to the sprue nest (3) and the annular runner (5).

6. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The cross section of the bridge (6) is wide and thin and flat, with a thickness of 10-15 mm. The bridge is connected to the lower part of the annular runner (5) and the upper part of the terminal runner (7), and the height ratio of the annular runner (5) to the bridge (6) is greater than 5.

7. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The cross-sectional dimensions of the annular runner (5) and the terminal runner (7) are the same as the cross-sectional dimensions of the drainage runner (4); the cross-sectional dimensions of the terminal runner (7) and the cross-sectional dimensions of the annular runner (5) are inverted in the vertical direction; the drainage runner (4) and the annular runner (5) are mainly located above the casting parting surface, and the terminal runner (7) and the bridge are mainly located below the casting parting surface.

8. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The water inlet of the entrapment (8) is introduced from the bottom of the terminal runner (7), and the water outlet is connected to the casting cavity through the bottom reverse.

9. The filter-free pouring system for low-slag wind power ductile iron castings according to claim 1, characterized in that: The sprue nest (3), the drainage runner (4), the annular runner (5), the bridge (6), the terminal runner (7), and the ingrate (8) are all located at the bottom of the casting cavity; the total cross-sectional dimensions of the sprue (2), the drainage runner (4), the bridge (6), and the ingrate (8) are in a ratio of 1:3-5:3-5:4-6.

10. The pouring process of the non-filter pouring system for low-slag wind power ductile iron casting according to claim 1, characterized in that: The following steps are involved: Step 1: After the casting sand mold is assembled, a casting adhesive is used to glue the sand box corresponding to the pouring cup (1) and the casting sand mold together, so that the drainage sprue (105) of the pouring cup (1) is connected to the sprue (2), and an iron plate (104) is placed at the bottom of the molten iron outlet chamber (102) of the pouring cup (1); Step 2: Use an electric furnace to melt ductile iron molten iron according to the composition requirements, and quickly heat the molten iron to 1520-1540°C after the composition is qualified, then cut off the power and let the molten iron stand for 5-8 minutes. During the standing period, repeatedly sprinkle the slag remover into the molten iron and remove the slag; Step 3: After the standing period, pour the molten iron into the ladle according to the pouring weight requirement, use the wire feeding method to spheroidize and inoculate the molten iron, and then sprinkle the slag remover again and remove the slag; Step 4: The molten iron ladle after the spheroidizing inoculation treatment is transferred to the casting sand mold, the temperature of the molten iron is measured and slag cotton is placed at the ladle mouth of the molten iron ladle, and pouring is performed at a temperature of 1350-1380°C. Subsequently, the molten iron is quickly poured into the molten iron injection chamber (101) within a time range of 15-20 seconds until the molten iron in the pouring cup (1) is nearly full. When the molten iron level in the pouring cup (1) begins to drop, the molten iron is continued to be poured into the molten iron injection chamber (101) and the molten iron level in the pouring cup (1) is always kept in a nearly full state. When the weight of the poured molten iron reaches the expected weight, the pouring is stopped. During the process of pouring the molten iron from the molten iron ladle into the molten iron injection chamber (101), the molten iron is subjected to inoculation treatment along the flow to improve the inoculation effect and prevent inoculation decline.

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