Casting structure of a shearer transition frame
By setting riser units and chills at key parts of the coal mining machine transition frame, the gating system was optimized, casting defects were resolved, and casting quality and service life were improved.
Patent Information
- Application Number
- CN202521474398.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-15
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-07-15
AI Technical Summary
Existing coal mining machine transition frame casting structures often exhibit casting defects such as porosity, shrinkage cavities, and gas porosity, affecting service life and casting quality.
Riser units, including multiple risers and chills, are set in key parts of the sand core to optimize the gating system and solve casting defects by compensating for the shrinkage of the molten metal.
It improves the density of the transition frame material, reduces casting defects, extends service life, and lowers casting costs.
Smart Images
Figure CN224673741U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of coal mining machine technology, specifically relating to a casting structure for a coal mining machine transition frame. Background Technology
[0002] Casting is the process of pouring molten metal into a mold, allowing it to cool and solidify to obtain parts with the desired shape and properties. For cast steel components like the transition frame of a coal mining machine, due to their large size and complex structure, the support plates, cylinder connecting lugs, and traction connecting lugs are all critical load-bearing parts, especially the base of the support plate which bears the weight of the entire machine and the transmission of mining force during coal mining. However, existing casting structures or processes often exhibit casting defects such as porosity, shrinkage cavities, or cracks at hot spots. These defects significantly impact casting quality, casting precision, casting cost, and casting automation, severely affecting the service life of the transition frame. Utility Model Content
[0003] The purpose of this utility model is to address the shortcomings of existing technologies by providing a casting structure for a coal mining machine transition frame, which solves the main casting defects such as porosity, shrinkage cavities, and air holes that occur inside the cast steel parts of large and complex transition frames, and ensures the material density of the transition frame material.
[0004] This utility model provides a casting structure for a transition frame of a coal mining machine. The transition frame includes a support plate for supporting the entire machine and transmitting coal mining force during the coal mining process, and a cylinder connecting lug and a traction connecting lug respectively connected to a hydraulic cylinder and a traction device. The casting structure includes: a sand core for casting to form the transition frame; and a riser unit composed of multiple risers, at least on the upper surface of the sand core and corresponding to the positions of the hydraulic cylinder connecting lug, the traction connecting lug, and the intersection of the support plate with the hydraulic cylinder connecting lug and the traction connecting lug.
[0005] Preferably, the riser unit includes a first riser disposed on the upper surface of the sand core at a position corresponding to the traction connecting lug, and the number of the first risers is two, each corresponding to one of the two traction connecting lugs.
[0006] Preferably, the riser unit further includes a second riser disposed on the upper surface of the sand core at a position corresponding to the intersection of the support plate, the cylinder connecting lug, and the traction connecting lug, the second riser being cuboid in shape.
[0007] Preferably, there are two second risers, which are arranged side by side.
[0008] Preferably, the first riser and / or the second riser are at least 200 mm above the top of the pallet and at least 100 mm away from the vertical surface of the pallet 101.
[0009] Preferably, the riser unit further includes a third riser disposed above the second riser, the third riser being smaller than the second riser.
[0010] Preferably, the riser unit further includes a fourth riser located on the upper surface of the sand core at a position corresponding to the top surface of the support plate.
[0011] Preferably, the casting structure further includes chills located at the bottom of the traction connecting lug and / or the bottom of the hydraulic cylinder connecting lug.
[0012] Preferably, the casting structure further includes a gating system, which includes an inner gate located at the bottom of the riser to avoid the trunnion hole sand core of the traction connecting lug and / or the hydraulic cylinder connecting lug.
[0013] Preferably, the gating system includes an ingate, a runner, and a sprue, wherein the ingate and the runner are perpendicular to each other, one end of the ingate is connected to the runner or the sprue, and the other end is connected to the riser; the ingate employs two runners. The ceramic ingate; and / or, the ratio of the cross-sectional areas of the sprue, the runner and the ingate is 1:1.15:1.5.
[0014] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of this utility model.
[0015] The positive and progressive effects of this utility model are as follows:
[0016] According to the coal mining machine transition frame casting structure involved in this utility model, risers are respectively set on the upper surface of the sand core body at the positions corresponding to the cylinder connecting ears, traction connecting ears, and the intersection of the support plate with the cylinder connecting ears and traction connecting ears. In this way, during the steel pouring process, the risers can compensate for the shrinkage of the molten metal during the casting process, solve the casting defects such as porosity, shrinkage cavities and gas pores generated inside the large transition frame cast steel parts, and ensure the material density of the transition frame material. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of the transition frame of the coal mining machine in an embodiment of this utility model.
[0018] Figure 2 This is a schematic diagram of the completed casting structure of the coal mining machine transition frame in an embodiment of this utility model.
[0019] Figure 3 This is a simulation diagram of the casting process of the coal mining machine transition frame casting structure in an embodiment of this utility model. Detailed Implementation
[0020] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.
[0021] <Example>
[0022] like Figure 1 and Figure 2 As shown, this embodiment discloses a casting structure for a coal mining machine transition frame, used to cast the coal mining machine transition frame 100 shown in the figure. Figure 1 As shown, the transition frame 100 includes a support plate 101 for supporting the entire machine and transmitting mining force during the coal mining process, and a cylinder connecting lug 102 and a traction connecting lug 103 respectively connected to the hydraulic cylinder (not shown in the figure) and the traction device (not shown in the figure). Based on the structure of the transition frame 100, the corresponding casting structure includes: a sand core body 10 and a riser unit 20.
[0023] like Figure 2 As shown, the sand core 10 and the transition frame 100 are structurally matched and used to form the transition frame 100 by pouring molten steel. It should be noted that, to better illustrate the optimized casting structure of this embodiment corresponding to the molten steel pouring process, and to highlight the structural design of the riser unit 20, Figure 2 The diagram shows the structure after the molten steel has been poured. Only a portion of the sand core 10 is shown in the diagram, which does not affect the description of the casting structure in this embodiment.
[0024] The riser unit 20 consists of multiple risers, all of which are located on the upper surface of the sand core 10, and at least at the positions corresponding to the cylinder connecting lug 102, the traction connecting lug 103, and the intersection of the support plate 101 with the cylinder connecting lug 102 and the traction connecting lug 103. Thus, during the steel pouring process, the riser unit 20 can compensate for the shrinkage of the molten metal during casting, resolving casting defects such as porosity, shrinkage cavities, and gas porosity inside the large transition frame cast steel parts. Specifically, as shown... Figure 3 As shown, by setting riser units 20 for feeding, the porosity (structure of the area marked 210 in the figure), shrinkage cavities (structure of the area marked 220 in the figure), or air holes are concentrated at each riser of riser unit 20, avoiding these casting defects in the casting and ensuring the material density of the transition frame.
[0025] Specifically, in Figure 2 In the sand core 10, the riser unit 20 includes a first riser 21 located on the upper surface of the sand core 10 at a position corresponding to the traction connecting lug 103. The first riser 21 is cylindrical. In a preferred embodiment, there are two first risers 21, each corresponding to one of the two traction connecting lugs 103.
[0026] Secondly, the riser unit 20 also includes a second riser 22 disposed on the upper surface of the sand core 10 at a position corresponding to the intersection of the support plate 101 with the cylinder connecting lug 102 and the traction connecting lug 103. The second riser 22 is cuboid in shape and its size is larger than that of the first riser 21. In a preferred embodiment, there are two second risers 22, which are arranged side by side.
[0027] Through the first riser 21 and the second riser 22 arranged as described above, the molten metal is effectively fed during the pouring process, ensuring the material density inside the casting.
[0028] In another embodiment, such as Figure 2 As shown, the first riser 21 and / or the second riser 22 are at least 200mm above the top of the support plate 101 and at least 100mm away from the vertical surface of the support plate 101. This increases the static pressure head, which is beneficial for liquid feeding of the casting, and also forms a concentrated heat zone, improving the feeding efficiency of the core riser, increasing the process yield, and facilitating subsequent riser cutting operations, reducing the skill requirements for workers.
[0029] In another embodiment, such as Figure 2 As shown, the riser unit 20 also includes a third riser 23 disposed above the second riser 22. The size of the third riser 23 is much smaller than that of the second riser 22, and it is used for venting.
[0030] In another embodiment, such as Figure 2 As shown, the riser unit 20 also includes a fourth riser 24 located on the upper surface of the sand core 10 at a position corresponding to the top surface of the pallet 101, for venting, thereby enabling the smooth discharge of gas inside the pallet 101 and having a certain function of collecting slag and dirt, reducing inclusions and porosity defects at the top of the pallet.
[0031] In another embodiment, such as Figure 2 As shown, the casting structure of this embodiment also includes chills 30 located at the bottom of the traction connecting lug 103 and / or the bottom of the hydraulic cylinder connecting lug 103. Thus, in the casting process of a thick and irregularly shaped cast steel part like the coal mining machine transition frame 100, based on the structural characteristics of the transition frame 100, the use of chills at key locations and hot spots, such as the bottom of the traction connecting lug and the bottom of the hydraulic cylinder connecting lug, not only enhances the cooling of the casting near the chills and improves the metallographic structure, but also continuously lowers the temperature of the molten steel in contact with the phase during filling, causing the molten steel to shrink prematurely, thereby improving the feeding capacity of the gating system and reducing the shrinkage of the casting after solidification in the gating system.
[0032] In another embodiment, the casting structure also includes a gating system 40, which adopts an open gating system design principle and a bottom-pouring design. That is, the gating system includes an ingate located at the bottom of the riser unit 20. Specifically, the molten metal enters the mold cavity through the bottom of the traction connecting lug 103 to avoid the sand core of the trunnion hole of the traction connecting lug 103 and / or the hydraulic cylinder connecting lug 103, so that the molten steel can directly enter the mold cavity, reducing the impact force of the molten steel on the sand core and reducing defects such as sand inclusion and sand adhesion caused by the impact of molten steel.
[0033] Specifically, the gating system includes an ingate, a horizontal gating system, and a vertical gating system. The ingate and the horizontal gating system are perpendicular to each other. One end of the ingate connects to the horizontal gating system or the vertical gating system, and the other end connects to the riser. In a preferred embodiment, based on the structure of the coal mining machine transition frame 100, the gating weight (GC) is approximately 6950 kg. Therefore, two ingates can be used. The system utilizes a ceramic ingate. Furthermore, the final selected gating system features a cross-sectional ratio of approximately 1:1.15:1.5 for the sprue, runner, and ingate, ensuring a high flow rate and stable filling of the molten steel. Additionally, a gating recess can be placed in front of the ingate to slow down the filling speed of the molten steel and provide some slag-blocking effect.
[0034] The casting structure of this embodiment features a rationally designed riser, chill, and gating system. The process is optimized and verified through computer simulation technology. The rational and efficient use of risers, chills, and gating system during the casting process successfully solves the main casting defects such as porosity, shrinkage cavities, and gas pores that occur inside the complex structure of large transition frame cast steel parts.
[0035] The scope of protection of this utility model is not limited to the above-described embodiments. Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its scope and spirit. If these modifications and variations fall within the scope of the claims of this utility model and their equivalents, then the intent of this utility model also includes these modifications and variations.
Claims
1. A casting structure for a transition frame of a coal mining machine, the transition frame comprising a support plate for supporting the entire machine and transmitting mining force during coal mining, and hydraulic cylinder connecting ears and traction connecting ears respectively connected to a hydraulic cylinder and a traction device, characterized in that, The casting structure includes: Sand core body, used for casting to form the transition frame; A riser unit consisting of multiple risers is provided at least on the upper surface of the sand core and at a position corresponding to the intersection of the cylinder connecting lug, the traction connecting lug, and the support plate with the cylinder connecting lug and the traction connecting lug.
2. The casting structure of the coal mining machine transition frame according to claim 1, characterized in that, The riser unit includes a first riser located on the upper surface of the sand core at a position corresponding to the traction connecting lug. There are two first risers, each corresponding to one of the two traction connecting ears.
3. The casting structure of the coal mining machine transition frame according to claim 2, characterized in that, The riser unit further includes a second riser disposed on the upper surface of the sand core at a position corresponding to the intersection of the support plate, the cylinder connecting lug, and the traction connecting lug. The second riser is cuboid in shape.
4. The casting structure of the coal mining machine transition frame according to claim 3, characterized in that, There are two second risers, which are arranged side by side.
5. The casting structure of the coal mining machine transition frame according to claim 3, characterized in that, The first riser and / or the second riser are at least 200mm above the top of the pallet and at least 100mm away from the vertical surface of the pallet.
6. The casting structure of the coal mining machine transition frame according to claim 4, characterized in that, The riser unit further includes a third riser disposed above the second riser, the third riser being smaller than the second riser.
7. The casting structure of the coal mining machine transition frame according to claim 1, characterized in that, The riser unit also includes a fourth riser located on the upper surface of the sand core at a position corresponding to the top surface of the support plate.
8. The casting structure of the coal mining machine transition frame according to claim 1, characterized in that, The casting structure also includes chills located at the bottom of the traction connecting lug and / or the bottom of the hydraulic cylinder connecting lug.
9. The casting structure of the coal mining machine transition frame according to claim 1, characterized in that, The casting structure also includes a gating system. The gating system includes an inner gating port located at the bottom of the riser to avoid the trunnion hole sand core of the traction connecting lug and / or the hydraulic cylinder connecting lug.
10. The casting structure of the coal mining machine transition frame according to claim 9, characterized in that, The gating system includes an ingate, a runner, and a sprue. The ingate and the runner are perpendicular to each other. One end of the ingate is connected to the runner or the sprue, and the other end is connected to the riser. The ingate uses two channels. The ceramic ingate; and / or, the ratio of the cross-sectional areas of the sprue, the runner and the ingate is 1:1.15:1.5.