A heavy spindle housing casting and casting method thereof

Abstract

The present invention discloses a heavy-duty spindle housing casting and a casting method thereof. A casting sand mold and multiple casting sand cores are manufactured according to the structural shape of the spindle housing. Multiple casting sand cores are lowered into the casting sand mold to obtain a casting cavity. The casting sand cores and the component sand mold are provided with a first chill assembly, a second chill assembly, and a third chill assembly. When manufacturing the casting sand mold, a pouring system is provided, wherein the pouring system includes a gate channel provided above a parting surface, the gate channel is connected to a horizontal runner, a vertical runner is provided below the horizontal runner, and a multi-layered ingrown runner is provided on the vertical runner. The ingrown runner is connected to the side wall of the casting cavity and a riser assembly is further provided above the vertical runner. After molten iron is smelted, the casting is poured, and the casting is naturally cooled after pouring. The chill, riser, and layered ingrown runner facilitate the flow of molten iron to the entire cavity structure, ensuring smooth and sufficient filling of the cavity and avoiding the generation of defects such as pores, inclusions, shrinkage cavities, and shrinkage.

Description

Technical Field

[0001] The invention relates to the technical field of heavy machine tool component casting, and in particular to a heavy spindle box casting and a casting method thereof. Background Art

[0002] The spindle box is a key component of the horizontal lathe, used to arrange the machine tool's working spindle and its transmission parts and corresponding additional mechanism components. There are many shaft holes distributed on the box, which are mainly used to carry the spindle. The dimensional accuracy of the shaft holes directly affects the machining accuracy of the machine tool. The spindle box is usually made of gray cast iron and is made by casting. The production of small spindle boxes is relatively simple, but for large and heavy spindle boxes, their casting defects will also be magnified and multiplied due to the increase in volume and weight. However, this type of box casting is not allowed to have defects such as shrinkage cavities, shrinkage, sand holes, slag holes, etc. after processing. Before the finished product is delivered, it is necessary to use a sample to detect the relevant dimensions of the inner cavity. The inner cavity of the casting is an oil tank and oil leakage is not allowed. Therefore, an effective casting method is required to produce qualified large-tonnage spindle box castings. Summary of the Invention

[0003] The purpose of the present invention is to provide a heavy-duty spindle housing casting and a casting method thereof in view of the problems existing in the prior art.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] On the one hand, the present invention provides a heavy-duty spindle box casting, including an integrally formed box bottom plate, a box top plate, a box left side plate, a box right side plate and a box back plate, and a front plate assembly arranged on the front side of the spindle box casting; a first parallel transverse partition and a second transverse partition are provided in the spindle box casting, the first transverse partition is arranged close to the box bottom plate, a vertical partition is provided between the second transverse partition and the box top plate, a large chamber is formed between the vertical partition and the box left side plate, and a small chamber is formed between the vertical partition and the box right side plate; a spindle mounting channel passing through up and down on the side where the large chamber is located is provided on the box top plate, the second transverse partition, the first transverse partition and the box bottom plate, and a secondary shaft mounting channel passing through up and down on the side where the small chamber is located; the spindle mounting channel is provided with a first columnar mounting area between the first transverse partition and the box bottom plate, and the spindle mounting channel is provided with a second columnar mounting area in the large chamber.

[0006] The spindle box casting forms a rectangular box structure through the box bottom plate, the box top plate, the box left plate, the box right plate, the box back plate and the front plate assembly, which can be used to arrange the working spindle of the machine tool and its transmission parts and components of the corresponding additional mechanisms. The spindle mounting channel on the side where the large chamber is located is mainly used to carry the spindle. In order to improve its bearing capacity and stability, the first cylindrical mounting area and the second cylindrical mounting area are set at the spindle mounting channel. The setting of these two mounting areas can also improve the dimensional accuracy and installation accuracy of the shaft hole, which is beneficial to improving the machining accuracy of the machine tool.

[0007] The first cylindrical mounting area is close to the end face of the spindle housing, and bearings and other components can be set to support the spindle. Its axial length is smaller than the axial length of the second cylindrical mounting area. The second cylindrical mounting area can better support the spindle in the middle, thereby improving the stability of the spindle installation and transmission.

[0008] Furthermore, the first columnar mounting area includes a first cylindrical structure connecting the first transverse partition and the box bottom plate, and the periphery of the first cylindrical structure is also provided with a plurality of reinforcing ribs connected to the first transverse partition and the box bottom plate.

[0009] Furthermore, the large chamber is provided with a pair of third transverse partitions connected to the left side panel of the box, the vertical partition and the back panel of the box, the second columnar mounting area includes a second cylindrical structure arranged between the pair of third transverse partitions, and the outer periphery of the second cylindrical structure is also provided with a plurality of reinforcing ribs connected to the third transverse partitions.

[0010] Furthermore, the small chamber is further provided with a plurality of fourth transverse partitions connected to the right side plate of the box, the vertical partitions and the back plate of the box, and the secondary shaft installation channels are multiple and arranged side by side.

[0011] Furthermore, a plurality of windows are provided on the right side panel of the box body; and the front panel assembly includes a plurality of crisscrossing panels.

[0012] A second aspect of the present invention provides a casting method for a heavy-duty spindle housing casting, the casting method comprising the following steps: selecting a parting surface, with the surface of the housing top plate being the parting surface; using a resin sand process, pit molding or sand box molding;

[0013] A casting sand mold and multiple casting sand cores are manufactured according to the structural shape of the spindle housing, and multiple casting sand cores are lowered into the casting sand mold to obtain a casting cavity; the casting sand core at least includes a first core head and a first sand core corresponding to the first cylindrical mounting area, and a second core head and a second sand core corresponding to the second cylindrical mounting area; the first sand core is arranged at the periphery of the first core head and a first chill assembly is provided thereat, the second sand core is located at the periphery of the second core head and a second chill assembly is provided thereat, and the casting sand mold is provided with a third chill assembly in the area corresponding to the first transverse partition and the second transverse partition;

[0014] When making the casting sand mold, a pouring system is provided, the pouring system comprising a gate channel provided above the parting surface, the gate channel being connected to a horizontal runner, a vertical runner being provided below the horizontal runner, a multi-layer ingrown runner being provided on the vertical runner, the ingrown runner being connected to the side wall of the casting cavity; a riser assembly is also provided on the parting surface;

[0015] Molten iron is smelted, and the composition of the molten iron is designed to be: C: 2.9%-3.1%, Si: 1.65-1.85%, Mn: 0.65%-0.85%, S: 0.05%-0.07%, P: 0.07%-0.085%, Cr: 0.2%-0.4%, and the rest is Fe;

[0016] Pouring: the pouring temperature is controlled at 1350-1380℃ and the pouring time does not exceed 150s; after pouring, the casting is cooled naturally.

[0017] Furthermore, the first chill assembly includes a plurality of chills embedded in the outer peripheral surface of the first core head, and a plurality of chills embedded in the casting sand mold corresponding to the first sand core and distributed around the first core head.

[0018] Furthermore, the second chill assembly includes a plurality of chills embedded in the outer circumference of the second core head and the inner circumference of the second sand core, and a plurality of chills are also provided below the second sand core and around the second core head.

[0019] Furthermore, the third chiller assembly is a chiller buried in the casting sand mold corresponding to the first transverse partition and the second transverse partition, and a chiller on the left side plate and the right side plate of the box between the first transverse partition and the second transverse partition; the riser assembly includes an insulating riser arranged around the outer ring and the shaft hole, and a shrinkage feeding riser arranged at different wall thicknesses.

[0020] Furthermore, at least two vertical runners are provided on each side, and the ingates are distributed at least in the upper, middle and lower positions. The upper ingate corresponds to the position where the top plate of the box is formed, the lower ingate corresponds to the position where the bottom plate of the box is formed, and the middle ingate corresponds to the position where the second transverse partition is formed.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. The spindle box casting forms a rectangular box structure through the box bottom plate, the box top plate, the box left plate, the box right plate, the box back plate and the front panel assembly, which can be used to arrange the working spindle of the machine tool and its transmission parts and components of the corresponding additional mechanisms. The spindle mounting channel on the side where the large chamber is located is mainly used to carry the spindle. In order to improve its bearing capacity and stability, the first cylindrical mounting area and the second cylindrical mounting area are set at the spindle mounting channel. The setting of these two mounting areas can also improve the dimensional accuracy and installation accuracy of the shaft hole, which is beneficial to improving the processing accuracy of the machine tool; 2. In this casting method, cold irons are set on both the sand core and the sand mold, and inner and outer cold irons are designed at the shaft hole position. According to the position and shape of the shaft hole, the inner and outer cold irons are designed to be ring-shaped, which is beneficial to the conduction and dispersion of heat and improves the cooling efficiency and uniformity. Strengthen the chilling effect, balance the cooling rate of the entire casting, and avoid shrinkage defects in the hot zone near the shaft hole; 3. The layered design of the gate is conducive to the flow of molten iron to the entire cavity structure, ensuring smooth and sufficient filling of the cavity, avoiding the occurrence of defects such as pores and inclusions; the gate area is calculated by weight to avoid pouring time that is too long or too short, reduce solidification time, prevent excessive internal stress of the casting, and thus reduce deformation and cracks; and the gate is distributed along the rib plate to conform to the shape of the casting itself to ensure filling during the entire pouring process Smooth, without turbulence; 4. Design an inner gate along the parting surface, and replenish the parting surface molten iron in the later stage of pouring to avoid poor fusion with the core support due to temperature drop when the molten iron fills the parting surface. The core support set on the parting surface is to support the cover box. It is to melt in the molten iron after pouring and eventually become a part of the casting; 5. The insulation risers around the outer ring and the shaft hole, as well as the shrinkage feeding risers set at different wall thicknesses, are beneficial to the overall shrinkage feeding of the casting, especially the shrinkage feeding near the shaft hole, to ensure that there are no shrinkage holes or shrinkage defects in the installation channel where the shaft hole is located. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the overall structure of a heavy-duty spindle box casting of the present invention. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the overall structure of a heavy-duty spindle box casting of the present invention. Figure 2 ;

[0024] Figure 3This is a front structural schematic diagram of a heavy-duty spindle housing casting of the present invention;

[0025] Figure 4 A schematic diagram of the pouring system, chiller and riser arrangement of a heavy-duty spindle housing casting of the present invention;

[0026] Figure 5 A schematic side view of the pouring system, chiller and riser arrangement of a heavy-duty spindle housing casting of the present invention;

[0027] Figure 6 is a schematic diagram of a second chiller assembly of the present invention;

[0028] Figure 7 is a schematic diagram of a first chiller assembly of the present invention;

[0029] Figure 8 A front view schematic diagram of the gating system of the present invention relative to the casting cavity;

[0030] Figure 9 A side view of the gating system of the present invention relative to the casting cavity;

[0031] In the figure: 1. Box bottom plate; 2. Box top plate; 3. Box left side plate; 4. Box right side plate; 5. Box back plate; 6. Front panel assembly; 7. Second horizontal partition plate; 8. First horizontal partition plate; 9. Main shaft installation channel; 10. Sub-shaft installation channel; 11. Second columnar installation area; 1101. Second cylinder structure; 12. First columnar installation area; 1201. First cylinder structure; 13. Reinforcement rib plate; 14. Vertical partition plate; 1 5. Third horizontal partition; 16. Window; 17. First chiller assembly; 1701. Chiller one; 1702. Chiller two; 1703. Chiller three; 18. Second chiller assembly; 1801. Chiller four; 1802. Chiller five; 1803. Chiller six; 1804. Chiller seven; 19. Third chiller assembly; 20. Gate channel; 21. Horizontal runner; 22. Vertical runner; 23. Inner runner; 24. Insulation riser; 25. Feeding riser. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," etc., etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Example 1

[0034] like Figures 1 to 3 As shown, a heavy-duty spindle box casting comprises an integrally formed box bottom plate 1, a box top plate 2, a box left side plate 3, a box right side plate 4 and a box back plate 5, as well as a front plate assembly 6 arranged on the front of the spindle box casting; a parallel first transverse partition plate 8 and a second transverse partition plate 7 are provided in the spindle box casting, the first transverse partition plate 8 is arranged close to the box bottom plate 1, a vertical partition plate 14 is provided between the second transverse partition plate 7 and the box top plate 2, and a large partition plate is formed between the vertical partition plate 14 and the box left side plate 3. A small chamber is formed between the chamber and the right side plate 4 of the box body; a main shaft mounting channel 9 running through the upper and lower parts is provided on the box body top plate 2, the second transverse partition 7, the first transverse partition 8 and the box body bottom plate 1 on the side where the large chamber is located, and a secondary shaft mounting channel 10 running through the upper and lower parts is provided on the side where the small chamber is located; the main shaft mounting channel 9 is provided with a first columnar mounting area 12 between the first transverse partition 8 and the box body bottom plate 1, and the main shaft mounting channel 9 is provided with a second columnar mounting area 11 in the large chamber.

[0035] The spindle box casting forms a rectangular box structure through the box bottom plate 1, the box top plate 2, the box left side plate 3, the box right side plate 4, the box back plate 5 and the front panel assembly 6, which can be used to arrange the working spindle of the machine tool and its transmission parts and components of the corresponding additional mechanisms. The spindle mounting channel on the side where the large chamber is located is mainly used to carry the spindle. In order to improve its bearing capacity and stability, the first cylindrical mounting area and the second cylindrical mounting area are set at the spindle mounting channel. The setting of these two mounting areas can also improve the dimensional accuracy and installation accuracy of the shaft hole, which is beneficial to improving the machining accuracy of the machine tool.

[0036] The first cylindrical mounting area 12 is close to the end face of the spindle housing, and bearings and other components can be set to support the spindle. Its axial length is smaller than the axial length of the second cylindrical mounting area. The second cylindrical mounting area 11 can better support the spindle in the middle, thereby improving the stability of the spindle installation and transmission.

[0037] Due to the importance of the first cylindrical mounting area 12 and the second cylindrical mounting area 11, the dimensional accuracy and shape assurance during their production are also very important. Therefore, during the casting process of the spindle box casting, the molding requirements of these two areas are relatively high, and it is necessary to ensure that there are no defects such as shrinkage cavities, porosity, and sand holes in these areas.

[0038] In addition to separating the internal area of ​​the entire box into different spaces, the first transverse partition 8, the second transverse partition 7 and the vertical partition 14 also serve to assist in the installation of shaft parts and increase the structural strength and stability; the area between the first transverse partition 8 and the second transverse partition 7 can be used to install transmission parts, so that the main shaft and the secondary shaft are connected together through a gear set, so that this area is connected; the large chamber and the small chamber separated by the vertical partition are used to arrange the main shaft and the secondary shaft respectively, which can provide better support on the one hand and separate the two on the other hand to avoid mutual influence during operation.

[0039] Furthermore, the first cylindrical mounting area 12 includes a first cylindrical structure 1201 connecting the first transverse partition 8 and the box bottom plate 1. The outer periphery of the first cylindrical structure 1201 is also provided with a plurality of reinforcing ribs 13 connected to the first transverse partition 8 and the box bottom plate 1. The inner periphery of the first cylindrical structure 1201 is provided with bearings to support the main shaft, and the reinforcing ribs provided on the outer periphery can improve strength and stability.

[0040] Furthermore, the large chamber is provided with a pair of third transverse partitions 15 connected to the left side panel 3 of the box (or the vertical partition on the left), the vertical partition 14 on the right and the back panel 5 of the box, and the second columnar mounting area 11 includes a second cylindrical structure 1101 arranged between the pair of third transverse partitions 15, and the outer periphery of the second cylindrical structure 1101 is also provided with a plurality of reinforcing ribs 13 connected to the third transverse partitions.

[0041] The arrangement of a pair of the third transverse partitions 15 can form a structure connecting the second cylindrical structure 1101. A reinforcing rib 13 is also arranged between the two to enhance strength and stability. Bearings can also be arranged on the inner periphery of the second cylindrical structure 1101 to support the main shaft.

[0042] Furthermore, the small chamber is provided with a plurality of fourth transverse partitions connected to the right side panel 4 of the box, the vertical partition 14 and the back panel 5 of the box, and the secondary shaft installation channels are arranged in four rows, two large and two small.

[0043] Furthermore, a plurality of windows 16 are provided on the right side panel 4 of the box to facilitate the installation of components such as the secondary shaft, as well as subsequent maintenance; the front panel assembly 6 includes a plurality of crisscrossing panels, the box bottom panel, the box top panel, the box left side panel, the box right side panel, the box back panel, and the first, second, third, and fourth horizontal partitions and vertical partitions. The panels are all provided at the front end face, that is, a slightly wider structure, forming a front panel assembly. This structure can also improve strength and stability, while leaving open space for subsequent installation and maintenance. Example 2

[0044] A casting method for a heavy spindle housing casting in embodiment 1, combined with Figures 4 to 9 As shown, the above structure is cast in an integrated manner, and the casting method includes the following steps:

[0045] Select the parting surface and use the surface where the box top plate 2 is located as the parting surface; adopt resin sand technology, pit molding or sand box molding; in this way, the entire cavity part of the spindle box casting can be arranged in the pit or sand box, which can reduce the difficulty of casting and is also beneficial to its overall molding. The pit and the sand box can be equipped with a cover box, and the structure of the cover box will also be simpler.

[0046] The spindle box casting described in Example 1 has a tonnage of more than 50 tons and an outline size of 2824*2689*3126mm. The box has many structures inside and contains multiple layers of cavities. Using traditional casting methods, the wall thickness at locations such as the casting shaft hole is large, which is prone to shrinkage defects.

[0047] A casting sand mold and multiple casting sand cores are manufactured according to the structural shape of the spindle housing, and the multiple casting sand cores are lowered into the casting sand mold to obtain a casting cavity; the casting sand core includes at least a first core head and a first sand core corresponding to the first cylindrical mounting area 12, and a second core head and a second sand core corresponding to the second cylindrical mounting area 11; the first sand core is arranged at the periphery of the first core head and a first chill assembly 17 is provided thereat, the second sand core is located at the periphery of the second core head and a second chill assembly 18 is provided thereat, and a third chill assembly 19 is provided in the region of the casting sand mold corresponding to the first transverse partition 8 and the second transverse partition 7;

[0048] For the entire spindle box casting, it is necessary to set up a lot of sand cores. From the description of Example 1, it can be seen that the molding of the first cylindrical area and the second cylindrical area where the spindle is installed is more critical, and the wall thickness of these areas is inconsistent, and there are more hot nodes. Therefore, the sand cores and sand molds are treated differently when setting them. The first chill assembly, the second chill assembly and the third chill assembly are set to enhance the chilling effect of these areas, so that the cooling rate of the entire casting can be controlled, and shrinkage cavities and shrinkage defects in thick and large sections are avoided.

[0049] The sand core design incorporates two main air outlet channels to ensure unobstructed air flow and reduce the risk of choking during pouring. First, a φ20 / 30 air outlet rod is designed at the core head of the multi-layer sand core, connecting it from top to bottom to ensure unobstructed air flow for the lower sand core. Second, six air outlet slots are designed at the core head of the sand mold (outer mold). Air cords are used to guide each layer of sand core into the air outlet slot to assist in air release.

[0050] A hard point is designed on the top sand core near the parting surface, and a hard point is designed at the corresponding position of the cover box (the hard point is for placing refractory bricks) so that core supports can be placed to prevent the core from lifting.

[0051] A special core bone is set in the sand core to increase the core bone strength, enhance the stability and deformation resistance of the sand core, and prevent it from moving or breaking during the casting process. The core bone has multiple layers of annular round steel, and the outer periphery of the annular round steel is provided with axial round steel connected to it.

[0052] When making the sand mold of the casting, a pouring system is set up, and the pouring system includes a gate channel 20 arranged above the parting surface, the gate channel 20 is connected to a horizontal runner 21, a vertical runner 22 is provided below the horizontal runner 21, and a multi-layer ingrown runner 23 is provided on the vertical runner 22. The ingrown runner 23 is connected to the side wall of the casting cavity; a riser assembly is also arranged on the parting surface.

[0053] Molten iron is smelted, and the composition of the molten iron is designed to be (mass percentage): C: 2.9%-3.1%, Si: 1.65%-1.85%, Mn: 0.65%-0.85%, S: 0.05%-0.07%, P: 0.07%-0.085%, Cr: 0.2%-0.4%, and the rest is Fe;

[0054] Taking the material grade HT300 of the spindle housing casting as an example, the following alloy composition is designed:

[0055] Table 1: Molten iron composition (%)

[0056]

[0057] During pouring, the pouring temperature is controlled at 1360°C and the pouring time is about 140 seconds; after pouring, the casting is cooled naturally.

[0058] Before actually making sand cores, sand molds and pouring, a finite element simulation of the molding process of the spindle box casting will be carried out based on the above design and generation. Numerical simulation will be performed using PROcast software to analyze the large shrinkage tendency in the hot spot of the shaft hole of the casting. Based on the analysis results, the process will be improved and an internal cooling iron will be designed to fit the hot spot to prevent shrinkage defects in key areas.

[0059] Furthermore, the first cold iron assembly 17 includes a plurality of cold irons 1701 embedded in the outer peripheral surface of the first core head, and a plurality of cold irons 1702 embedded in the casting sand mold corresponding to the first sand core and distributed around the first core head, and cold irons 1703 are provided at the sand cores corresponding to the partitions on both sides.

[0060] The second cold iron assembly 18 includes several cold irons 1801 and 1802 buried in the outer circumference of the second core head and the inner circumference of the second sand core. Several cold irons 1803 are also provided around the second core head below the second sand core. Cold irons 1804 are provided at the sand cores corresponding to the vertical partitions on both sides.

[0061] This chiller arrangement is to install chillers on both the sand core and the sand mold. The chillers in these areas are arranged in correspondence. For castings, this means that inner and outer chillers are installed (in the first cylindrical structure 1201 and the second cylindrical structure 1101). That is, inner and outer chillers are designed at the shaft hole position. According to the position and shape of the shaft hole, the inner and outer chillers are designed into a ring shape, which is conducive to heat conduction and dispersion, and improves cooling efficiency and uniformity. It strengthens the chilling effect, balances the cooling rate of the entire casting, and avoids shrinkage defects such as shrinkage cavities and porosity in the hot zone near the shaft hole. Compared with the simple external chiller setting, this arrangement of the present method can achieve better cooling effect.

[0062] Furthermore, the third chill assembly 19 is a chill buried in the casting sand mold corresponding to the first transverse partition and the second transverse partition, as well as the chill on the left side plate and the right side plate of the box between the first transverse partition and the second transverse partition. This area is also a relatively important processing surface and is located below the pouring system. The arrangement of these chills is conducive to timely cooling of the molten iron that enters this area later.

[0063] The material grade of the above-mentioned chills is HT250, which is different from the material grade of the casting body. The side facing the casting cavity is also provided with coated sand or refractory coating, so that while it plays a cooling role, it also avoids its own melting and the casting sticking to the chill, ensuring the surface quality of the casting.

[0064] The riser assembly includes insulating risers 24 arranged around the outer ring and the shaft hole, and feeding risers 25 arranged at different wall thicknesses. The provision of these two risers facilitates shrinkage feeding of the entire casting, particularly near the shaft hole, ensuring that the mounting channel where the shaft hole is located is free of shrinkage cavities and porosity defects. Both the feeding riser and the insulating riser include a truncated cone-shaped portion that is larger at the top and smaller at the bottom, and a rectangular connecting portion. The truncated cone-shaped portion has an axial length of approximately 700 mm, a diameter at the small end of 110-140 mm, and a diameter at the large end of 160-190 mm. The rectangular connecting portion has a side length of 50-80 mm and a height of 30-40 mm.

[0065] Furthermore, at least two vertical runners 22 are provided on each side, and the ingrowns are distributed at least in the upper, middle and lower positions. The upper ingrown 23 corresponds to the position where the top plate of the box is formed, the lower ingrown 23 corresponds to the position where the bottom plate of the box is formed, and the middle ingrown corresponds to the position where the second transverse partition is formed.

[0066] The layered design of the gate facilitates the flow of molten iron to the entire cavity structure, ensuring smooth and sufficient filling of the cavity and avoiding defects such as air holes and inclusions.

[0067] The ingate area is calculated by weight to avoid excessive pouring time, shorten solidification time, and prevent excessive internal stress in the casting, thereby reducing deformation and cracking. The ingates are distributed along the ribs, conforming to the shape of the casting itself, ensuring smooth filling throughout the pouring process without turbulence.

[0068] An inner gate is designed along the parting surface, and molten iron is added to the parting surface in the later stage of pouring to avoid poor fusion with the core support due to temperature drop when the molten iron fills the parting surface. The core support set on the parting surface is to support the cover box, and it will melt in the molten iron after pouring and eventually become a part of the casting.

[0069] Specifically, a horizontal runner 21 is provided on each side of the casting cavity at the parting surface. Four vertical runners 22 are provided below each horizontal runner 21, with two vertical runners 22 forming a group and arranged in the front-to-back direction. Four ingates 23 are arranged spaced apart from top to bottom on each vertical runner 22. The horizontal runner 21 is 2600-2650 mm long and has a trapezoidal cross-section. The vertical runner 22 is 3100-3150 mm long and has a circular cross-section. The ingates 23 are 110-115 mm long and have a rectangular cross-section.

[0070] Assuming that the cross-sectional area of ​​the horizontal runner is S1, the cross-sectional area of ​​the vertical runner is S2, and the cross-sectional area of ​​the ingrown runner is S3, then S1>S2>S3; preferably, S1:S2=(2.8-3):1, S2:S3=(4-5):1; specifically, in this embodiment, S1=15000mm 2 , S2=5024mm 2 , S3=1150mm 2 This cross-sectional area setting ensures complete filling of the casting cavity, allowing multiple molten iron paths from top, middle, and bottom to enter the cavity in a stable and orderly manner, avoiding turbulence and insufficient pouring of molten iron in the cavity, and also contributing to uniform temperature in all parts of the casting.

[0071] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A casting method for a heavy spindle housing casting, characterized in that: The heavy-duty spindle box casting comprises an integrally formed box bottom plate, a box top plate, a box left side plate, a box right side plate and a box back plate, as well as a front plate assembly arranged on the front side of the spindle box casting; a parallel first transverse partition plate and a second transverse partition plate are provided in the spindle box casting, the first transverse partition plate being close to the box bottom plate, a vertical partition plate being provided between the second transverse partition plate and the box top plate, a large chamber is formed between the vertical partition plate and the box left side plate, and a small chamber is formed between the vertical partition plate and the box right side plate; a spindle mounting channel penetrating up and down is provided on the box top plate, the second transverse partition plate, the first transverse partition plate and the box bottom plate on the side where the large chamber is located, and a secondary shaft mounting channel penetrating up and down is provided on the side where the small chamber is located; the spindle mounting channel is provided with a first columnar mounting area between the first transverse partition plate and the box bottom plate, and the spindle mounting channel is provided with a second columnar mounting area in the large chamber; The casting method comprises the following steps: selecting a parting surface, with the surface of the box top plate being the parting surface; adopting resin sand technology, pit molding or sand box molding; A casting sand mold and multiple casting sand cores are manufactured according to the structural shape of the spindle housing, and multiple casting sand cores are lowered into the casting sand mold to obtain a casting cavity; the casting sand core at least includes a first core head and a first sand core corresponding to the first cylindrical mounting area, and a second core head and a second sand core corresponding to the second cylindrical mounting area; the first sand core is arranged at the periphery of the first core head and a first chill assembly is provided thereat, the second sand core is located at the periphery of the second core head and a second chill assembly is provided thereat, and the casting sand mold is provided with a third chill assembly in the area corresponding to the first transverse partition and the second transverse partition; When making the casting sand mold, a pouring system is provided, the pouring system comprising a gate channel provided above the parting surface, the gate channel being connected to a horizontal runner, a vertical runner being provided below the horizontal runner, a multi-layer ingrown runner being provided on the vertical runner, the ingrown runner being connected to the side wall of the casting cavity; a riser assembly is also provided on the parting surface; Molten iron is smelted, and the composition of the molten iron is designed to be: C: 2.9%-3.1%, Si: 1.65-1.85%, Mn: 0.65%-0.85%, S: 0.05%-0.07%, P: 0.07%-0.085%, Cr: 0.2%-0.4%, and the rest is Fe; Pouring: the pouring temperature is controlled at 1350-1380℃ and the pouring time does not exceed 150s; after pouring, the casting is cooled naturally.

2. The method for casting a heavy-duty spindle housing according to claim 1, characterized in that: The first chill assembly includes a plurality of chills embedded in the outer peripheral surface of the first core head, and a plurality of chills embedded in the casting sand mold and distributed around the first core head corresponding to the first sand core.

3. The method for casting a heavy-duty spindle housing according to claim 1, characterized in that: The second chill assembly includes a plurality of chills embedded in the outer circumference of the second core head and the inner circumference of the second sand core. A plurality of chills are also provided below the second sand core and around the second core head.

4. The method for casting a heavy-duty spindle housing casting according to claim 1, characterized in that: The third chiller assembly is a chiller buried in the casting sand mold corresponding to the first transverse partition and the second transverse partition, as well as a chiller on the left side plate and the right side plate of the box body between the first transverse partition and the second transverse partition; the riser assembly includes an insulating riser arranged around the outer ring and the shaft hole, and a shrinkage feeding riser arranged at different wall thicknesses.

5. The method for casting a heavy-duty spindle housing casting according to claim 1, characterized in that: At least two vertical runners are provided on each side, and the ingates are distributed at least in the upper, middle and lower positions. The upper ingates correspond to the position where the top plate of the box is formed, the lower ingates correspond to the position where the bottom plate of the box is formed, and the middle ingates correspond to the position where the second transverse partition is formed.

6. The method for casting a heavy-duty spindle housing according to claim 1, characterized in that: The first columnar mounting area includes a first cylindrical structure connecting the first transverse partition and the box bottom plate, and a plurality of reinforcing ribs connected to the first transverse partition and the box bottom plate are further provided on the periphery of the first cylindrical structure.

7. The method for casting a heavy-duty spindle housing casting according to claim 1, characterized in that: A pair of third transverse partitions connected to the left side panel of the box, the vertical partition and the back panel of the box are provided in the large chamber, and the second columnar mounting area includes a second cylindrical structure arranged between the pair of third transverse partitions, and the outer periphery of the second cylindrical structure is also provided with a plurality of reinforcing ribs connected to the third transverse partitions.

8. The method for casting a heavy-duty spindle housing casting according to claim 1, characterized in that: The small chamber is further provided with a plurality of fourth transverse partitions connected to the right side plate of the box, the vertical partitions and the back plate of the box, and the secondary shaft installation channels are arranged in a plurality in parallel.

9. The method for casting a heavy-duty spindle housing casting according to claim 1, characterized in that: The right side panel of the box body is also provided with a plurality of windows; the front panel assembly includes a plurality of crisscrossing panels.

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