Ventilated brake disc casting device for improving production efficiency

Abstract

The application discloses a ventilated brake disc pouring device capable of improving production efficiency and relates to the technical field of ventilated brake disc pouring, which comprises a sprue unit and a mold unit, the sprue unit adopts a multi-stage sprue structure of a straight sprue, a cross sprue, a split cross sprue and a vertical sprue, and the mold unit comprises two symmetrical mold groups, each of which comprises two symmetrical forming molds arranged in an upper and lower mode; and each group of symmetrical vertical sprues is connected with inner gates of the two symmetrical forming molds arranged in an upper and lower mode. The device adopts a double-layer symmetrical mold layout of 'one mold four cavities', and is matched with a tree-shaped shunt structure of '1 straight sprue 2 cross sprues 4 split cross sprues 32 vertical sprues', so that molten iron can be quickly and uniformly distributed to the four cavities, synchronous efficient filling is supported, the output of castings per unit time is directly improved from the layout and the runner design, and the market demand for brake discs caused by the rapid development of the new energy automobile industry is effectively matched.

Description

Technical Field

[0001] This invention relates to the field of ventilated brake disc casting technology, and more particularly to a ventilated brake disc casting device for improving production efficiency. Background Technology

[0002] In recent years, the new energy vehicle industry has experienced rapid development. By 2025, domestic sales of new energy vehicles had reached nearly 40% of total passenger vehicle sales, becoming a core direction for the development of the automotive industry. Compared with traditional fuel vehicles, new energy vehicles have a significantly increased overall chassis weight due to the installation of drive battery packs, which places higher demands on the performance of the vehicle's braking system.

[0003] As a core component of the braking system, the automotive brake disc generates braking torque through friction with the friction pads to impede vehicle movement. To meet the braking requirements of new energy vehicles, the industry generally improves braking performance by increasing the brake disc diameter and friction area. Brake disc blanks are mainly produced from gray cast iron through a casting process, followed by machining, surface coating, and other processes to complete the finished product before being installed in vehicles.

[0004] However, in the existing casting production process, the increase in the diameter and area of ​​the brake disc has led to a significant reduction in the number of product cavities that can be arranged on the mold plate of conventional casting production molds. Traditional gating systems mostly adopt a two-cavity arrangement in one mold, which results in low production efficiency and makes it difficult to meet the market demand for brake discs under the rapid development of the new energy vehicle industry.

[0005] Traditional brake disc casting systems also have many technological defects: turbulence is easily generated during molten iron pouring, forming primary and secondary slag. Slag entering the mold cavity can easily cause slag hole defects in the brake disc, affecting product quality; unreasonable molten iron filling method and insufficient venting of the mold cavity can easily lead to air entrapment during filling, resulting in defects such as shrinkage porosity inside the brake disc; the centralized design of the ingate not only slows down the molten iron filling speed but also increases the difficulty of separating the ingate from the product, increasing the labor intensity of operators.

[0006] In addition, the existing ventilated brake disc casting system lacks rationality in the design of the gating structure and cross-sectional area ratio, resulting in uneven iron and water flow, low filling efficiency, and no effective filtration and flow stabilization structure, which cannot effectively purify the molten iron and further aggravates the product defect rate.

[0007] For example, invention application No. 202210526232.5 discloses a casting mold for brake discs. It connects and fixes the upper and lower sand boxes by setting a partition core sand and isolates the two cavities to ensure the forming effect of the brake disc. By setting multiple vent holes on the core head, air in the molten iron is discharged in time, which effectively solves defects such as scorching and porosity. However, it also has the following problems: the mold still adopts the traditional one-mold-two-cavity arrangement and does not optimize the filling path and flow rate of the molten iron. During the casting process, the molten iron may still generate oxide slag due to the turbulent flow. The overall improvement effect on reducing labor intensity and improving product quality is limited.

[0008] Therefore, there is a need for a ventilated brake disc casting system that can improve production efficiency, optimize product quality, and reduce the intensity of production operations, addressing the key needs of current industry pain points. Summary of the Invention

[0009] To address the aforementioned problems, the present invention aims to provide a ventilated brake disc casting device that improves production efficiency. This device solves the existing defects in ventilated brake disc casting systems, such as turbulent flow of molten iron, excessive oxide slag, insufficient venting of the mold cavity leading to air entrapment and loosening, concentrated internal gate design causing slow filling speed and separation difficulties, unreasonable runner structure and cross-sectional area ratio leading to uneven flow distribution and low filling efficiency, and lack of an effective filtration and flow stabilization structure to purify molten iron. This invention aims to improve production efficiency, optimize product quality, and reduce production workload.

[0010] The objective of this invention can be achieved through the following technical solution: a ventilated brake disc casting device for improving production efficiency, comprising:

[0011] The gating unit adopts a multi-level gating structure, including a straight gating, which connects to two symmetrical horizontal gatings, each of the horizontal gatings connects to two symmetrical sub-horizontal gatings, and each of the sub-horizontal gatings connects to multiple sets of symmetrical vertical gatings.

[0012] The mold unit adopts a four-cavity layout and includes two symmetrical mold groups, each of which includes two symmetrical molding molds, one upper and one lower.

[0013] Each set of symmetrical vertical runners connects to the inner gates of two symmetrical molding dies.

[0014] As a further embodiment of the present invention, the horizontal runner includes a first horizontal runner and a second horizontal runner; wherein, the first horizontal runner connects a first sub-horizontal runner and a third sub-horizontal runner, and the second horizontal runner connects a second sub-horizontal runner and a fourth sub-horizontal runner.

[0015] As a further embodiment of the present invention, the vertical gating system includes 16 upper vertical gating systems and 16 lower vertical gating systems;

[0016] The first horizontal gating channel connects the upper vertical gating channels No. 1-4 and the lower vertical gating channels No. 17-20;

[0017] The second horizontal gating channel connects the upper vertical gating channels No. 5-8 and the lower vertical gating channels No. 21-24.

[0018] The third horizontal gating channel connects the upper vertical gating channels 9-12 and the lower vertical gating channels 25-28.

[0019] The fourth horizontal gating channel connects the upper vertical gating channels No. 13-16 and the lower vertical gating channels No. 29-32.

[0020] As a further embodiment of the present invention, the mold unit includes a first mold group and a second mold group; the first mold group includes a first molding mold and a second molding mold; the second mold group includes a third molding mold and a fourth molding mold; wherein each molding mold is provided with 8 inlet gates;

[0021] The eight inlet gates of the first molding mold are respectively connected to the upper vertical runners No. 1 to 4 and the upper vertical runners No. 9 to 12;

[0022] The eight inlet gates of the second molding die are respectively connected to the upper vertical runners No. 5 to 8 and the upper vertical runners No. 13 to 16;

[0023] The eight inlet gates of the third molding mold are respectively connected to the No. 17-20 lower vertical runners and the No. 25-28 lower vertical runners;

[0024] The eight inlets of the fourth molding mold are respectively connected to the lower vertical runners No. 21-24 and No. 29-32.

[0025] As a further embodiment of the present invention, a filter sheet for filtering molten iron is provided on the inner side of the first horizontal pouring channel, and a filter sheet for filtering molten iron is provided on the inner side of the second horizontal pouring channel.

[0026] As a further embodiment of the present invention, in the multi-stage gating structure, the cross-sectional area ratio of the vertical gating runner: horizontal gating runner *2: sub-horizontal gating runner *4: vertical gating runner *32 is: .

[0027] As a further embodiment of the present invention, the cross-sectional area of ​​the direct gating system is determined based on the flow-blocking cross-sectional area, and is expressed as follows:

[0028]

[0029] Where m is the weight of the casting, ρ is the liquid phase density of cast iron, T is the casting time, μ is the flow resistance coefficient, g is the gravitational acceleration, and Hp is the head height.

[0030] As a further embodiment of the present invention, the casting time formula is expressed as:

[0031]

[0032] Where m is the weight of the casting. These are empirical values, ranging from 1.15 to 1.3.

[0033] As a further embodiment of the present invention, the formula for the pressure head height is expressed as:

[0034]

[0035] Where Ho is the height of the upper mold, P is the height of the upper mold of the casting, and C is the height of the casting.

[0036] The beneficial effects of this invention are:

[0037] 1. The device of this invention adopts a double-layer symmetrical mold layout of "one mold, four cavities". Addressing the industry pain point of low production efficiency caused by the traditional "one mold, two cavities" arrangement for large-size brake discs, this invention designs the mold unit as two symmetrical mold groups, each group containing two symmetrical forming molds, one above the other. This allows for the simultaneous production of four brake disc castings in a single pour, doubling the output compared to traditional methods. Simultaneously, the accompanying tree-like flow distribution structure of "1 sprue → 2 runners → 4 branch runners → 32 vertical runners" can quickly and evenly distribute molten iron to the four cavities, supporting synchronous and efficient filling. From the layout and flow channel design, this directly increases the casting output per unit time, effectively matching the market demand for brake discs driven by the rapid development of the new energy vehicle industry.

[0038] 2. This invention's device, through the synergistic effect of multiple structural designs, effectively controls the flow of molten iron and reduces casting defects. Ceramic filters are installed in the horizontal runners to effectively trap solid inclusions such as oxide scale and refractory material particles in the molten iron, purifying it at the source and reducing the risk of slag porosity and gas porosity defects in the castings. Secondly, the use of a progressively enlarging runner ratio buffers and reduces the molten iron flow rate, facilitating impurity uplift and gas discharge, achieving stable filling. The horizontal runners employ an arc-shaped design to fit the mold, with smooth transitions at each connection, significantly reducing flow resistance and eddy currents, avoiding secondary oxide slag caused by turbulent flow. Each forming mold receives flow through eight symmetrical ingates, allowing molten iron to fill the cavity evenly and smoothly from multiple directions, avoiding defects such as localized overheating, cold shuts, and shrinkage porosity caused by concentrated flow, thereby comprehensively improving the internal density, surface finish, and overall yield of the castings.

[0039] 3. This invention offers a systematic solution to several drawbacks of traditional brake disc casting systems (such as a limited number of cavities, turbulent molten iron flow, excessive oxide slag, uneven filling, and difficulty in separation due to concentrated ingates). It integrates multiple objectives, including improved production efficiency (four-cavity layout in a single mold), optimized flow process (multi-stage flow distribution and area ratio design), molten iron purification (filter settings), and mold protection (smooth, low-speed filling). By precisely calculating the cross-sectional area of ​​the sprue and optimizing the proportions of each gating stage, it achieves scientific control of filling speed and pressure. The multi-ingate design ensures rapid and uniform filling while dispersing the ingate cross-section, reducing the difficulty and operational intensity of separating the gating system from the casting. This effectively meets the demand for highly efficient and stable production of large-size, high-quality brake disc castings for new energy vehicles. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the external structure of the device of the present invention;

[0041] Figure 2 This is a schematic diagram of the gating unit of the present invention;

[0042] Figure 3 This is a schematic diagram of the mold unit of the present invention;

[0043] Figure 4 This is another structural schematic diagram of the gating unit of the present invention.

[0044] 100. Sprue unit; 110. Straight sprue; 111. Buffer chamber; 120. First horizontal sprue; 121. Filter plate one; 130. Second horizontal sprue; 131. Filter plate two; 140. First sub-horizontal sprue; 150. Third sub-horizontal sprue; 160. Second sub-horizontal sprue; 170. Fourth sub-horizontal sprue; 180. Upper vertical sprue; 190. Lower vertical sprue;

[0045] 200, Mold unit; 210, First mold group; 220, Second mold group; 230, First molding mold; 240, Second molding mold; 250, Third molding mold; 260, Fourth molding mold. Detailed Implementation

[0046] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols 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 are only used to explain the present invention, and should not be construed as limiting the present invention.

[0047] Example 1:

[0048] like Figure 1As shown, the present invention discloses a ventilated brake disc casting device for improving production efficiency, which mainly includes a gating unit 100 and a mold unit 200.

[0049] The gating unit 100 is used to form the molten iron gating channel when pouring the brake disc. The gating unit 100 adopts a multi-stage gating structure, specifically divided into four stages: a straight gating channel 110, a horizontal gating channel, a sub-horizontal gating channel, and a vertical gating channel.

[0050] The sprue 110 serves as the initial channel for molten iron to enter the casting system. Its upper end is connected to the pouring cup, and its lower end is connected to the sprue. Its cross-sectional area has been precisely calculated to ensure that the molten iron can be transported smoothly and continuously, reducing eddies and splashes.

[0051] The horizontal sprue receives the molten iron from the sprue 110 and distributes it to the subsequent horizontal sprues. The horizontal sprues adopt a symmetrical structure and are symmetrically arranged on both sides of the sprue 110, perpendicular to the sprue 110. This structure can ensure that the molten iron is evenly distributed in the horizontal sprue and avoid segregation or uneven filling caused by excessive flow on one side.

[0052] The total cross-sectional area of ​​the horizontal sprue is larger than that of the vertical sprue 110, which can buffer the flow rate of molten iron and stabilize the pressure.

[0053] The horizontal runner further divides the molten iron delivered from the horizontal runner. Based on the size of the brake disc and the number of cavities, several horizontal runners are set up, and each horizontal runner is connected to several vertical runners to achieve uniform distribution of molten iron.

[0054] The horizontal sprues also adopt a symmetrical structure, symmetrically set on both sides of the horizontal sprue. The length and cross-sectional area of ​​each horizontal sprue are optimized according to the number and position of the vertical sprues it connects to, so as to ensure that the molten iron flow rate and flow rate in each horizontal sprue are consistent.

[0055] The horizontal runner is curved, and the curvature matches the outer curvature of the mold assembly. This design allows the molten iron to flow more smoothly, reduces flow resistance, and avoids kinetic energy loss and eddy current phenomena caused by right-angle turns and other structures.

[0056] Furthermore, the sprue and the gating system are on the same plane, and the connection between the sprue and the gating system is smoothly transitioned, which further optimizes the flow of molten iron, reduces local resistance, and thus improves the filling efficiency and stability of the entire casting system.

[0057] As the final channel connecting the horizontal runners and the mold cavity, the vertical runners are arranged in groups with a symmetrical structure. One horizontal runner connects to multiple groups of vertical runners. Each group of vertical runners is symmetrically arranged on the upper and lower sides of the horizontal runner. The vertical runners are perpendicular to the horizontal runners. The upper and lower vertical runners connect to different molding dies. The diameter of the vertical runners is precisely calculated to match the flow rate of the horizontal runners and the filling requirements of the mold cavity.

[0058] The inlet of the vertical sprue and the outlet of the horizontal sprue both feature a smooth transition design, ensuring that molten iron flows smoothly from the horizontal sprue into the vertical sprue and avoiding turbulence. The length of the vertical sprue is adjusted according to the position of the mold in the sand mold, so that the molten iron can enter the cavity at a suitable speed and pressure, ensuring full filling while preventing the cavity walls from being washed away or gas from being trapped due to excessive flow rate.

[0059] The gating unit 100 of this invention adopts a four-level structure: a sprue 110, a horizontal sprue, a sub-horizontal sprue, and a vertical sprue. The sprue 110 serves as the primary channel for molten iron to enter the casting system. Its cross-sectional dimensions are precisely determined based on the total mass of the casting and the casting time. It typically employs a tapered structure, wider at the top and narrower at the bottom, to ensure stable flow of molten iron under gravity and reduce slag entrapment and oxidation. The horizontal sprue receives the molten iron from the sprue 110 and performs initial distribution. It is located near the parting line and uses a uniform cross-section design to ensure uniform flow velocity of molten iron within the horizontal sprue, avoiding uneven flow distribution due to velocity differences. The sub-horizontal sprues extend from the horizontal sprue and are distributed radially, further distributing the molten iron to the various vertical sprues. The number and location of the vertical sprues are rationally planned according to the layout of the mold cavity to achieve a balanced supply of molten iron.

[0060] Furthermore, a filter is installed inside the horizontal runner, which can effectively remove inclusions in the molten iron and improve the quality of the casting. The filter can be made of high-temperature resistant ceramic material, and its pore structure is precisely designed to trap solid impurities such as oxide scale and refractory material particles in the molten iron.

[0061] This design not only prevents impurities from entering the mold cavity with the molten iron, thus avoiding defects such as porosity and slag inclusions in the casting, but also reduces the problem of poor mold filling caused by impurities. As a result, the casting qualification rate is improved while the workload of subsequent cleaning processes is reduced.

[0062] The horizontal sprue features inward inclination on both sides of the filter plate, typically controlled between 3° and 5°. This design guides the molten iron smoothly through the filter plate, preventing impact from excessively high local flow velocities. It also helps maintain good fluidity of the molten iron before and after filtration, reducing eddies and turbulence. Through the combined effect of the inclined structures on both sides, the molten iron forms a gradual flow field as it enters the filter plate area, resulting in more uniform stress on the filter plate, extending its service life, further ensuring the stability of the filtration effect, and guaranteeing the purity of the molten iron entering subsequent sprues.

[0063] The mold unit 200 and the runner unit 100 are configured to correspond, as follows: Figure 3 As shown, the mold unit 200 includes two symmetrical mold groups, each mold group including two symmetrical molding molds, one upper and one lower.

[0064] Each forming mold cavity is equipped with heat dissipation fins, friction surface protrusions, and a central shaft hole forming pillar that match the structure of the ventilated brake disc. The cavity surface is polished to ensure the surface finish of the casting. The two mold groups form a symmetrical layout, allowing the gating unit 100 to simultaneously pour castings into the forming molds in both mold groups, enabling simultaneous production of both groups and significantly increasing the casting output per unit time.

[0065] Specifically, each molding die has multiple ingates symmetrically opened on both sides. Each ingate corresponds to the upper or lower vertical runner connected to the horizontal runner. In this way, each molding die is connected to the two horizontal runners through the vertical runners on both sides.

[0066] After being diverted through the horizontal gating system, the molten iron smoothly enters the mold cavity through the upper or lower vertical gating systems on either side of the forming mold, respectively, via the ingates on both sides of the mold. This symmetrical arrangement of multiple ingates ensures uniform filling of the mold cavity with molten iron, preventing defects such as slag entrapment and oxidation caused by excessively fast or slow flow rates in certain areas. It also reduces porosity and shrinkage within the casting, ensuring uniform density throughout the brake disc. The rational distribution of multiple ingates also shortens the molten iron flow path, reduces flow resistance, and further increases the filling speed, thus meeting the efficiency requirements of simultaneous dual-group production and providing a strong guarantee for achieving efficient and stable casting production.

[0067] Example 2:

[0068] Based on Example 1, this example discloses a specific structure of a ventilated brake disc casting device for improving production efficiency, specifically as follows: Figure 1 and Figure 2 As shown,

[0069] The sprue includes a first sprue 120 and a second sprue 130. The first sprue 120 and the second sprue 130 are symmetrically arranged side by side on both sides of the sprue 110, and their extension directions are perpendicular to the axis of the sprue 110, forming an inverted "T" shaped distribution structure. The bottom of the sprue 110 is provided with a downwardly recessed buffer cavity 111. The bottom of the buffer cavity 111 is connected to the middle of the first sprue 120 and the second sprue 130 through a transition section, so that the molten iron flowing down from the sprue 110 can first enter the buffer cavity 111 for preliminary flow stabilization and pressure reduction, and then be evenly distributed into the first sprue 120 and the second sprue 130.

[0070] The cross-sectional areas of the first sprue 120 and the second sprue 130 near the end of the sprue 110 are slightly larger than the cross-sectional area of ​​the sprue 110. This design can effectively avoid turbulence and splashing caused by the sudden reduction of the flow area when the molten iron enters the sprue, and ensure that the molten iron can smoothly and continuously transition from the sprue 110 to the sprue.

[0071] Furthermore, such as Figure 4 As shown, a filter plate 121 is installed inside the first horizontal runner 120, and a filter plate 131 is installed inside the second horizontal runner 130. The filter plates can effectively remove inclusions in the molten iron and improve the quality of the casting. The filter plates are located after the transition section connecting the horizontal runner and the buffer cavity 111, about one-third of the length from the end of the horizontal runner. This allows the molten iron to be filtered after it has been initially stabilized in the buffer cavity 111, preventing inclusions from accumulating further in the horizontal runner or entering the subsequent cavity with the molten iron.

[0072] Furthermore, to facilitate replacement, the sides of the first horizontal runner 120 and the second horizontal runner 130 are provided with detachable observation and maintenance ports corresponding to the filter positions. These ports are sealed by a cover plate. When the filter reaches the end of its service life or becomes clogged, the cover plate can be quickly opened for replacement, effectively shortening equipment maintenance time and ensuring the continuity of the pouring process.

[0073] Furthermore, the first horizontal runner 120 connects the first sub-horizontal runner 140 and the third sub-horizontal runner 150, and the second horizontal runner 130 connects the second sub-horizontal runner 160 and the fourth sub-horizontal runner 170. The sum of the cross-sectional areas of the sub-horizontal runners is slightly larger than the sum of the cross-sectional areas of the horizontal runners.

[0074] The first and third horizontal runners 140 and 150 are symmetrical about the first horizontal runner 120, and the second and fourth horizontal runners 160 and 170 are symmetrical about the second horizontal runner 130. The horizontal runners are arc-shaped, and the arc conforms to the outer arc of the mold assembly. This design allows the molten iron to flow more smoothly, reduces flow resistance, and avoids the loss of molten iron kinetic energy and eddy current phenomena caused by right-angle turns and other structures.

[0075] The first horizontal gating 140, the third horizontal gating 150, the second horizontal gating 160, and the fourth horizontal gating 170 are each connected to a vertical gating duct.

[0076] Specifically, the vertical gating system includes 16 upper vertical gating channels 180 and 16 lower vertical gating channels 190. The first horizontal gating channel 140 connects upper vertical gating channels 1-4 (180) and lower vertical gating channels 17-20 (190); the second horizontal gating channel 160 connects upper vertical gating channels 5-8 (180) and lower vertical gating channels 21-24 (190); the third horizontal gating channel 150 connects upper vertical gating channels 9-12 (180) and lower vertical gating channels 25-28 (190); and the fourth horizontal gating channel 170 connects upper vertical gating channels 13-16 (180) and lower vertical gating channels 29-32 (190).

[0077] Corresponding to the structure of the runner unit 100, the mold unit 200 includes a first mold group 210 and a second mold group 220; the first mold group 210 includes a first molding mold 230 and a second molding mold 240; the second mold group 220 includes a third molding mold 250 and a fourth molding mold 260, and each molding mold is provided with 8 inlet gates.

[0078] The eight ingates on the first forming mold 230 are respectively connected to the upper vertical runners 1-4 and 5-8, ensuring that the molten iron flowing from the first horizontal runner 140 and the second horizontal runner 160 can enter the cavity of the first forming mold 230 accurately and evenly through these ingates.

[0079] The eight ingates of the second forming mold 240 are connected to the lower vertical runners 17-20 and 21-24, respectively, to receive molten iron from the first horizontal runner 140 and the second horizontal runner 160.

[0080] The eight ingates on the third forming mold 250 are connected to the upper vertical sprues 180 (numbers 9-12) and the upper vertical sprues 180 (numbers 13-16), so that the molten iron transported by the third horizontal sprue 150 and the fourth horizontal sprue 170 can be smoothly injected into the second forming mold 240.

[0081] The eight ingates of the fourth forming mold 260 are connected to the lower vertical runners 190 (numbers 25-28) and 190 (numbers 29-32) respectively, receiving the molten iron distributed by the third horizontal runner 150 and the fourth horizontal runner 170.

[0082] With the above structure, each molding die receives molten iron from different runners through eight ingates. This multi-ingate layout design allows molten iron to fill the cavity simultaneously and evenly from multiple directions, effectively shortening the filling time and reducing defects such as cold shuts and incomplete filling caused by excessive local flow distances of molten iron. Simultaneously, the rational distribution of the eight ingates creates a relatively stable flow field within the cavity, preventing excessive turbulence and slag entrapment during filling, which is beneficial for improving the internal quality and surface finish of the casting.

[0083] The position and size of each ingate are precisely calculated to match the outlet of the sprue and the inlet of the mold cavity, ensuring that the molten iron has the appropriate flow rate and volume when entering the forming mold cavity. This avoids defects such as sand erosion and oxidation caused by excessive flow rate, and also prevents problems such as cold shut and incomplete pouring caused by excessive flow rate, thereby ensuring that each forming mold can stably and efficiently form castings.

[0084] Example 3:

[0085] Based on Embodiment 1 or 2, this embodiment optimizes the cross-sectional areas of the straight pouring channel 110, the horizontal pouring channel, the sub-horizontal pouring channel, and the vertical pouring channel to create a hierarchical difference. Specifically, the cross-sectional area of ​​the straight pouring channel 110 is the smallest, followed by the cross-sectional areas of the horizontal pouring channel, then the sub-horizontal pouring channel, and finally the cross-sectional area of ​​the vertical pouring channel is the largest.

[0086] This tiered design, with its progressively increasing cross-sectional area from the sprue 110 to the gating system, conforms to the pressure and flow rate variations during molten iron flow. When molten iron flows from the sprue 110 into the runner, the flow velocity decreases due to the larger cross-sectional area of ​​the runner, helping to stabilize the flow and reduce turbulence. Subsequently, the molten iron enters the gating system, where its cross-sectional area further increases, and the flow velocity continues to slow down, allowing for a more even distribution of molten iron to each gating system within the gating system. As the final channel connecting the gating system and the ingate, the larger cross-sectional area of ​​the gating system ensures a sufficient and stable supply of molten iron to each ingate, preventing insufficient local flow from affecting the filling process.

[0087] Through this hierarchical optimization of cross-sectional area, the flow of molten iron in the entire casting system becomes more orderly and stable, and the pressure loss is effectively controlled, further improving the uniformity and stability of molten iron filling the cavity, thus laying a solid foundation for improving casting quality and production efficiency.

[0088] Specifically, the cross-sectional area of ​​the sprue 110 is determined based on the flow-blocking cross-sectional area. The cross-sectional area of ​​the sprue 110 is approximately equal to the flow-blocking cross-sectional area. The diameter of the sprue 110 pipe can be determined based on the cross-sectional area of ​​the sprue 110. The calculation of the flow-blocking cross-sectional area requires comprehensive consideration of key parameters such as the weight of the poured weight, the density of the molten iron, the pouring time, and the acceleration due to gravity. It is precisely derived through a specific fluid mechanics formula, which is expressed as follows:

[0089]

[0090] Where m is the pouring weight, ρ is the liquid phase density of cast iron, T is the pouring time, μ is the flow obstruction coefficient, g is the gravitational acceleration, and Hp is the pressure head height. The specific values ​​of each parameter need to be determined comprehensively in conjunction with the structural characteristics and production process requirements of the ventilated brake disc. By accurately controlling these parameters, the accuracy of the flow obstruction cross-sectional area calculation can be ensured, thereby providing a reliable basis for the dimensional design of the sprue 110 and subsequent runners, and achieving efficient and stable operation of the pouring system.

[0091] Furthermore, the formula for pouring time is expressed as:

[0092]

[0093] Where m is the weight of the casting. These are empirical values, ranging from 1.15 to 1.3.

[0094] The formula for indenter height is expressed as:

[0095]

[0096] Where Ho is the height of the upper mold, P is the height of the upper mold of the casting, and C is the height of the casting. The physical meaning and values ​​of each parameter must strictly follow the casting process specifications.

[0097] Ho, the upper mold height, refers to the vertical distance from the top surface of the sand box to the parting surface. Its value is determined according to the casting size and sand box specifications. Usually, sufficient static pressure head of molten iron is required to achieve smooth filling. P is the upper mold height of the casting, representing the height of the casting in the upper mold part. This parameter directly affects the flow path and pressure distribution of molten iron in the mold cavity. C is the total height of the casting, which covers the overall vertical dimension of the casting from the upper mold to the lower mold and is an important reference when calculating the pressure head height.

[0098] By accurately calculating the Hp value, key data support is provided for the derivation of the flow obstruction cross-sectional area, thereby ensuring the scientific and rational design of the entire gating system and helping the ventilated brake disc achieve efficient and high-quality casting production.

[0099] Furthermore, based on the determined cross-sectional area of ​​the sprue 110, the cross-sectional areas of the horizontal sprue, the sub-horizontal sprues, and the vertical sprues are determined. Specifically, in the multi-stage sprue structure, the sprue 110 connects to two horizontal sprues, each horizontal sprue connects to two sub-horizontal sprues, and each sub-horizontal sprue connects to eight vertical sprues, forming a tree-like flow distribution structure of "1 sprue 110 → 2 horizontal sprues → 4 sub-horizontal sprues → 32 vertical sprues". This multi-stage flow distribution design can effectively reduce the flow velocity of molten iron, allowing the molten iron to undergo a sufficiently smooth transition before entering the mold cavity, avoiding defects such as slag entrapment and oxidation caused by excessive flow velocity.

[0100] Specifically, the cross-sectional area ratio of the sprue: 2 horizontal runners: 4 separate horizontal runners: 32 vertical runners is 1:1.2:1.4-1.5:1.6-2.0. These ratios are determined based on the flow characteristics of molten iron, the structural features of the casting, and production experience. The horizontal runner has a slightly larger cross-sectional area than the sprue (1:1.2), which provides a buffer and stabilizes the flow, reducing the impact of molten iron entering the horizontal runner and aiding in the floating and separation of impurities. The cross-sectional area of ​​the separate horizontal runners is further increased to 1.4-1.5 times that of the sprue (110), further reducing the flow rate and allowing the molten iron to be distributed more evenly to each vertical runner. As the final channel for molten iron to enter the mold cavity, the vertical sprue is designed to have a total cross-sectional area 1.6-2.0 times that of the sprue 110, making it the largest part in the entire gating system. This design aims to reduce the final filling speed of the molten iron by using a larger ingate cross-sectional area, ensuring that the molten iron fills the mold cavity smoothly and orderly, avoiding erosion of the mold, and also facilitating the smooth discharge of gas inside the mold cavity, reducing the generation of casting defects such as porosity and sand holes, thereby ensuring the casting quality of the ventilated brake disc.

[0101] Example 4:

[0102] This embodiment illustrates the process of determining the cross-sectional area of ​​the direct casting channel based on Embodiment 3.

[0103] The data for the ventilation disc in this embodiment are as follows: casting weight is 16.5kg, outer diameter Ф350mm, height 50mm, mold plate size 800mm*900mm, and upper and lower sand mold heights are both 250mm; the gating system is calculated as follows:

[0104] Runner calculation: based on the formula for obstructing cross-sectional area:

[0105]

[0106] Where m is the casting weight, the theoretical casting weight is calculated as 16.5*4 / 0.80=82.5kg based on the product weight and expected yield.

[0107] ρ is the liquid phase density of cast iron, taken as 0.007 kg / cm³.

[0108] T is the pouring time, according to the formula μ′ is calculated to be 1.15-1.3 based on empirical values ​​for horizontal gray iron casting; for rapid filling, μ′ is taken as 1.15, and T is calculated as 1.15*. =10.5s.

[0109] μ is the flow resistance coefficient. This process is a wet sand process, so μ is taken as 0.5.

[0110] Hp is the indentation head height, expressed by the formula:

[0111]

[0112] Where Ho is the height of the upper mold, P is the height of the upper mold of the casting, and C is the height of the casting. Calculate Hp = 200 - 60² / 2 * 50 = 16cm (control the pouring liquid level at a height of 200mm in the upper mold).

[0113] calculate

[0114] =82.5 / (0.007*10.5*0.5*(2*980*16)½)=12.7cm²=1270mm².

[0115] Since the minimum area of ​​the gating system is the area of ​​the sprue 110, the diameter of the sprue 110 is calculated to be 40.2mm based on the S resistance. Considering the need for rapid filling, a 44mm diameter sprue 110 is selected.

[0116] To ensure slag-blocking effect, the ratio of the gating channels is: [first horizontal gating channel + second horizontal gating channel]: [first sub-horizontal gating channel + second sub-horizontal gating channel + third sub-horizontal gating channel + fourth sub-horizontal gating channel]: [32 * vertical gating channel] cross-sectional area ratio = 1:1.2:1.4-1.5:1.6-2.0; the cross-sectional areas of the 32 vertical gating channels are equal.

[0117] For example, the area of ​​the sprue 110 is 1520 mm²; the total area of ​​[first horizontal runner + second horizontal runner] is 1823 mm²; the total area of ​​[first sub-horizontal runner + second sub-horizontal runner + third sub-horizontal runner + fourth sub-horizontal runner] is 2203 mm²; and the total area of ​​[32*vertical runners] is 2736 mm².

[0118] To address the issue of limited single-mold placement for large-size brake discs, this invention employs a double-layer symmetrical mold group design, increasing the number of cavities per casting from the traditional "one mold, two cavities" to "one mold, four cavities," effectively doubling the number of castings cast per batch and directly improving production line efficiency. A tree-like multi-stage flow distribution structure is used: "1 sprue 110 → 2 runners → 4 branch runners → 32 ingates." Molten iron enters from the pouring cup and is distributed step-by-step through the sprue 110, runners, and branch runners, ultimately being injected simultaneously, evenly, and rapidly into four cavities from both sides through eight ingates per mold, totaling 32. This design shortens the molten iron flow path, reduces flow resistance, and achieves rapid, synchronous filling. Simultaneously, filter plates are installed in the runners to effectively intercept primary inclusions in the molten iron and stabilize the turbulence caused by the direct flow from the sprue 110, reducing the generation of secondary oxide slag. Furthermore, each runner stage utilizes an optimized proportion with progressively larger cross-sectional areas for flow field optimization. This gradually reduces the flow rate of molten iron, acting as a buffer and stabilizing agent, which helps impurities float to the surface and gases escape, reducing the risk of air entrapment during molding.

[0119] This invention achieves a doubling of production capacity through a "one mold, four cavities" layout. Through a comprehensive design that combines multi-stage diversion, slag removal, area ratio optimization, and flow channel structure optimization, it solves quality problems such as uneven filling, slag inclusions, and porosity that are prone to occur when casting multiple cavities simultaneously. Thus, while improving production efficiency, it ensures the stability and excellence of casting quality.

[0120] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0121] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0122] Furthermore, 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 invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0123] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0124] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

Claims

1. A ventilated brake disc casting device for improving production efficiency, characterized in that, include: The gating unit adopts a multi-level gating structure, including a straight gating, which connects to two symmetrical horizontal gatings, each of the horizontal gatings connects to two symmetrical sub-horizontal gatings, and each of the sub-horizontal gatings connects to multiple sets of symmetrical vertical gatings. The mold unit adopts a four-cavity layout and includes two symmetrical mold groups, each of which includes two symmetrical molding molds, one upper and one lower. Each set of symmetrical vertical runners connects to the inner gates of two symmetrical molding dies.

2. The ventilated brake disc casting device for improving production efficiency according to claim 1, characterized in that, The horizontal runner includes a first horizontal runner and a second horizontal runner; The first horizontal runner connects the first sub-horizontal runner and the third sub-horizontal runner, and the second horizontal runner connects the second sub-horizontal runner and the fourth sub-horizontal runner.

3. The ventilated brake disc casting device for improving production efficiency according to claim 2, characterized in that, The vertical gating system includes 16 upper vertical gating systems and 16 lower vertical gating systems; The first horizontal gating channel connects the upper vertical gating channels No. 1-4 and the lower vertical gating channels No. 17-20; The second horizontal gating channel connects the upper vertical gating channels No. 5-8 and the lower vertical gating channels No. 21-24. The third horizontal gating channel connects the upper vertical gating channels 9-12 and the lower vertical gating channels 25-28. The fourth horizontal gating channel connects the upper vertical gating channels No. 13-16 and the lower vertical gating channels No. 29-32.

4. The ventilated brake disc casting device for improving production efficiency according to claim 3, characterized in that, The mold unit includes a first mold group and a second mold group; the first mold group includes a first molding mold and a second molding mold; the second mold group includes a third molding mold and a fourth molding mold; wherein each molding mold is provided with 8 inlet gates; The eight inlet gates of the first molding mold are respectively connected to the upper vertical runners No. 1 to 4 and the upper vertical runners No. 5 to 8; The eight inlet gates of the second molding die are respectively connected to the lower vertical runners No. 17-20 and No. 21-24; The eight inlet gates of the third molding mold are respectively connected to the upper vertical runners No. 9-12 and No. 13-16; The eight inlet gates of the fourth molding mold are respectively connected to the lower vertical runners No. 25-28 and No. 29-32.

5. A ventilated brake disc casting device for improving production efficiency according to claim 2, characterized in that, A filter plate for filtering molten iron is provided on the inner side of the first horizontal pouring channel, and a filter plate for filtering molten iron is provided on the inner side of the second horizontal pouring channel.

6. A ventilated brake disc casting device for improving production efficiency according to claim 1, characterized in that, In the multi-stage gating structure, the cross-sectional area ratio of the vertical gating runner: 2 horizontal gating runners: 4 sub-horizontal gating runners: 32 vertical gating runners is: .

7. A ventilated brake disc casting device for improving production efficiency according to claim 6, characterized in that, The cross-sectional area of ​​the direct gating system is determined based on the flow-obstructing cross-sectional area, and is expressed as follows: Where m is the weight of the casting, ρ is the liquid phase density of cast iron, T is the casting time, μ is the flow resistance coefficient, g is the gravitational acceleration, and Hp is the head height.

8. A ventilated brake disc casting device for improving production efficiency according to claim 7, characterized in that, The formula for the pouring time is expressed as follows: Where m is the weight of the casting. These are empirical values, ranging from 1.15 to 1.

3.

9. A ventilated brake disc casting device for improving production efficiency according to claim 7, characterized in that, The formula for the indenter height is expressed as follows: Where Ho is the height of the upper mold, P is the height of the upper mold of the casting, and C is the height of the casting.

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