Sand core structure for casting middle hole of hollow shaft of large ore mill
By designing a new sand core structure, including a pouring system and a ventilation rope layer, the problem of insufficient ventilation in the center hole of the hollow shaft of a large mining mill was solved, the casting quality and production efficiency were improved, and the production cost was reduced.
Patent Information
- Application Number
- CN202422681415.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-05
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2034-11-05
AI Technical Summary
In the existing casting method, the sand core structure of the hollow shaft hole of the large mining mill leads to unstable casting quality, the existence of inner cavity crack defects caused by insufficient ventilation, and low repair efficiency, which increases production costs.
A new sand core structure is adopted, including a pouring system, a casting cavity and a sand core, which is designed as a ring structure with a ventilation rope layer. The distance between the ventilation rope layers is a hollow structure. The ventilation rope layer is connected to the air holes to realize a ventilation layer, thereby enhancing the air permeability of the sand core. By increasing the air permeability of the sand core, the frequency of air hole defects in the inner cavity is reduced.
The production efficiency of the hollow shaft hole of the large-scale mining mill is improved, the probability of the occurrence of cracks on the inner cavity surface is reduced, and the production cost is reduced.
Smart Images
Figure CN223368148U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of casting, and in particular relates to a sand core structure used for casting a central hole of a hollow shaft of a large-scale mining mill. Background Art
[0002] The hollow shaft, one of the important components of large-scale mining grinding equipment, usually has a cylindrical cavity on the inside and an I-shaped rotating body on the outside. In the commonly used casting method, the middle cavity is a cylindrical sand core. The existing casting method is to put foam in the sand core to increase the air permeability of the sand core. However, the amount of foam material put in each time is not fixed and the placement is also irregular, which makes the quality of the cast hollow shaft unstable and cannot effectively solve the cracks in the hollow shaft cavity caused by insufficient ventilation of the sand core. The crack defects can only be repaired at a later stage, and the repair is generally carried out by welding. This not only reduces production efficiency but also increases the production cost of the enterprise. Utility Model Content
[0003] In view of the problems existing in the background technology, the utility model provides a sand core structure for casting the center hole of the hollow shaft of a large-scale mining mill.
[0004] To achieve the above-mentioned purpose, the utility model adopts the following technical solutions: a sand core structure for casting the center hole of the hollow shaft of a large mining mill, comprising a pouring system, a casting cavity and a sand core, the pouring system being connected to the bottom of the casting cavity, the upper end face of the casting cavity being provided with a riser, and the riser being connected to the casting cavity; a vertical sand core is provided at the center of the casting cavity; the sand core is provided on a groove at the bottom center of the casting cavity, and a vertical air hole is provided at the center of the upper end face of the sand core; a ventilation rope layer is horizontally provided inside the sand core, the height between the ventilation rope layers is b, and the ventilation ropes of each layer are radially distributed with the air hole as the center.
[0005] The pouring system includes a gate, a sprue, a runner and an ingrown runner; the lower end of the gate is connected to the sprue, and the lower end of the sprue is connected to the runner; the ingrown runner is located below the casting cavity, the upper end of the ingrown runner is connected to the bottom of the casting cavity, and the lower end of the ingrown runner is connected to the runner.
[0006] A parting line is provided at the upper end of the casting cavity, which divides the casting cavity into an upper box and a lower box; positioning holes are provided on the contact surfaces of the upper box and the lower box, and the upper and lower positioning holes correspond to each other.
[0007] The riser is an annular structure, the outer diameter of the riser is larger than the outer diameter of the casting cavity, and the inner diameter of the riser is smaller than the inner diameter of the casting cavity.
[0008] A sand core seat is provided at the lower end of the sand core, and the sand core seat is matched with the groove at the bottom of the casting cavity.
[0009] The ventilation rope is a hollow structure, one end of the ventilation rope is connected to the air hole; the other end of the ventilation rope is buried in the sand core, and the distance between the ventilation rope and the outer wall of the sand core is amm, 50≤a≤70.
[0010] The height between the ventilation rope layers is bmm, 150≤b≤200.
[0011] The ventilation ropes of the ventilation rope layer are distributed radially, and the maximum distance between the ventilation ropes is cmm, 150≤c≤200.
[0012] The beneficial effects of the utility model are as follows: the utility model provides a sand core structure for casting the middle hole of the hollow shaft of a large mining mill. The sand core structure increases the cylindrical cavity of the sand core and uses an air outlet rope to connect the cavity, thereby enhancing the air outlet of the sand core, reducing the frequency of air hole defects in the inner cavity, reducing the probability of cracks on the surface of the inner cavity, improving production efficiency, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a structural diagram of the present utility model.
[0014] Figure 2 This is a top view of BB.
[0015] Figure 3 This is a bottom view of the BB.
[0016] Figure 4 This is the main view of the sand core.
[0017] Figure 5 This is the AA cross-section view.
[0018] Figure 6 This is a cross-sectional view of the ventilation rope.
[0019] In the figure: 1. gate, 2. sprue, 3. runner, 4. ingrown gate, 5. casting cavity, 8. positioning hole, 9. sand core, 10. riser, 11. upper box, 12. lower box, 91. sand core holder, 92. air hole, 93. ventilation rope. DETAILED DESCRIPTION
[0020] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the specification. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0021] The following is combined with Figure 1-6The specific embodiment of the present invention is further elaborated in detail: a sand core structure for casting a large-scale mining mill hollow shaft hole, comprising a pouring system, a casting cavity 5 and a sand core 9, wherein the pouring system is connected to the bottom of the casting cavity 5; the pouring system comprises a gate 1, a sprue 2, a runner 3 and an ingrown gate 4; the lower end of the gate 1 is connected to the sprue 2, and the lower end of the sprue 2 is connected to the runner 3; the ingrown gate 4 is located below the casting cavity 5, the upper end of the ingrown gate 4 is connected to the bottom of the casting cavity 5, and the lower end of the ingrown gate 4 is connected to the runner 3 connected; in this embodiment, the runner 3 is located below the casting cavity 5 and is connected to the casting cavity 5 through the ingrown channel 4; the runner 3 can be a circular cavity located below the casting cavity 5; when the runner 3 is a circular cavity, the ingrown channels 4 are multiple and evenly distributed above the runner 3; a riser 10 is provided on the upper end surface of the casting cavity 5, and the riser 10 is connected to the casting cavity 5; the riser 10 is an annular structure, the outer diameter of the riser 10 is larger than the outer diameter of the casting cavity 5, the inner diameter of the riser 10 is smaller than the inner diameter of the casting cavity 5, and is larger than the diameter of the vent hole of the sand core 9;
[0022] The upper end of the casting cavity 5 is provided with a parting line, which divides the casting cavity 5 into an upper box 11 and a lower box 12; positioning holes 8 are provided on the contact surface of the upper box 11 and the lower box 12, and the upper and lower positioning holes 8 correspond to each other; in order to facilitate sand casting, in this embodiment, the parting line is set at the connection between the middle and the upper end of the casting cavity 5; the positioning holes 8 are for facilitating the closing of the boxes;
[0023] A vertical sand core 9 is provided at the center of the casting cavity 5. The sand core 9 is arranged in a groove at the center bottom of the casting cavity 5. A sand core seat 91 is provided at the lower end of the sand core 9, and the sand core seat 91 is adapted to the groove at the bottom of the casting cavity 5. A vertical air hole 92 is provided at the center of the upper end surface of the sand core 9. A ventilation rope layer is horizontally provided inside the sand core 9. The height between the ventilation rope layers is bmm, 150≤b≤200. The ventilation ropes 93 in each layer are radially distributed with the air hole 92 as the center. The maximum distance between the ventilation ropes 93 is cmm, 150≤c≤200. Experiments have shown that maintaining the distance between the ventilation cords 93 between 150 mm and 200 mm not only saves costs but also ensures good ventilation inside the sand core. The ventilation cords 93 are hollow in structure, with one end of the ventilation cords 93 communicating with the air holes 92. The other end of the ventilation cords 93 is embedded in the sand core 9. The distance between the ventilation cords 93 and the outer wall of the sand core 9 is a mm, with 50 ≤ a ≤ 70. Experiments have shown that when a > 50 mm, molten steel will not leak out. When a > 70 mm, the design requirements cannot be met. In this example, a = 60 mm is used.
[0024] The use process of the present utility model is as follows: first, a casting cavity 5 and a pouring system are made, a riser 10 is arranged on the upper end surface of the casting cavity 5, and a sand core 9 is arranged on the groove at the center bottom of the casting cavity 5, and the upper box 11 and the lower box 12 are installed together; after the casting model is completed, molten steel is poured; the molten steel enters from the gate 1, passes through the sprue 2, the runner 3 and the ingrowth 4 in sequence, and is filled from the bottom up from the lower end of the casting cavity 5; after the pouring is completed, the casting begins to cool; during the filling and cooling process, the molten steel will release a large amount of heat, and the water and air in the sand core 9 will expand due to the heat, and these mixed gases enter the central channel of the ventilation rope 93, and enter the air hole 92 in the center of the sand core 9 through the central channel of the ventilation rope 93, and finally overflow from the air hole 92, thereby avoiding cracks caused by poor exhaust during the shrinkage of the hollow shaft casting.
[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
[0026] The parts not described in detail in this utility model are prior art.
Claims
1. A sand core structure for casting a large-scale mining mill hollow shaft hole, comprising a pouring system, a casting cavity (5) and a sand core (9), characterized by: The pouring system is connected to the bottom of the casting cavity (5), and the upper end surface of the casting cavity (5) is provided with a riser (10), and the riser (10) is connected to the casting cavity (5); a vertical sand core (9) is provided at the center of the casting cavity (5); the sand core (9) is provided on a groove at the bottom center of the casting cavity (5), and a vertical air hole (92) is provided at the center of the upper end surface of the sand core (9); a ventilation rope layer is horizontally provided inside the sand core (9), and the height between the ventilation rope layers is b, and the ventilation ropes (93) of each layer are radially distributed with the air hole (92) as the center.
2. The sand core structure for casting the center hole of the hollow shaft of a large mining mill according to claim 1, characterized in that: The pouring system comprises a gate (1), a sprue (2), a runner (3) and an ingrown runner (4); the lower end of the gate (1) is connected to the sprue (2), and the lower end of the sprue (2) is connected to the runner (3); the ingrown runner (4) is located below the casting cavity (5), the upper end of the ingrown runner (4) is connected to the bottom of the casting cavity (5), and the lower end of the ingrown runner (4) is connected to the runner (3).
3. The sand core structure for casting the central hole of the hollow shaft of a large-scale mining mill according to claim 1 is characterized by: A parting line is provided at the upper end of the casting cavity (5), and the parting line divides the casting cavity (5) into an upper box (11) and a lower box (12); positioning holes (8) are provided on the contact surfaces of the upper box (11) and the lower box (12), and the upper and lower positioning holes (8) correspond to each other.
4. The sand core structure for casting the center hole of the hollow shaft of a large mining mill according to claim 1 is characterized by: The riser (10) is an annular structure, the outer diameter of the riser (10) is larger than the outer diameter of the casting cavity (5), and the inner diameter of the riser (10) is smaller than the inner diameter of the casting cavity (5).
5. The sand core structure for casting the center hole of the hollow shaft of a large mining mill according to claim 1, characterized in that: The lower end of the sand core (9) is provided with a sand core seat (91), and the sand core seat (91) is adapted to the groove at the bottom of the casting cavity (5).
6. The sand core structure for casting the center hole of the hollow shaft of a large mining mill according to claim 1, characterized in that: The ventilation rope (93) is a hollow structure, one end of the ventilation rope (93) is connected to the air hole (92); the other end of the ventilation rope (93) is buried in the sand core (9), and the distance between the ventilation rope (93) and the outer wall of the sand core (9) is amm, 50≤a≤70.
7. The sand core structure for casting the center hole of the hollow shaft of a large-scale mining mill according to claim 1 is characterized by: The height between the ventilation rope layers is bmm, 150≤b≤200.
8. The sand core structure for casting the center hole of the hollow shaft of a large mining mill according to claim 1, characterized in that: The ventilation ropes (93) of the ventilation rope layer are distributed radially, and the maximum distance between the ventilation ropes (93) is cm, 150≤c≤200.