Structure for preventing casting flash from being generated at orifice of bolt hole of wear-resistant lining plate

Abstract

The utility model relates to a structure for preventing a wear-resistant lining plate bolt hole orifice from producing casting flashes, belongs to the technical field of casting molds, and solves the problems that in the prior art, the wear-resistant lining plate bolt hole orifice is easy to produce casting flashes and is difficult to polish and remove; and further, the problems of long processing period, high cost, uncontrollable product quality and the like are solved. The utility model discloses a structure for preventing casting flashes from being generated at an orifice. The structure comprises a bolt hole core, an auxiliary forming sheet and an upper box provided with a through hole, the bolt hole core is assembled in a positioning hole reserved in the lower box, and the bolt hole core and the through hole of the upper box are coaxially assembled; the auxiliary forming piece is assembled between the bolt hole core and the end face of the through hole of the upper box. According to the special structure provided by the invention, the auxiliary forming sheet is creatively adopted to carry out occupation in advance in the casting process, so that the generation of casting flashes is avoided, the subsequent processing difficulty is reduced, the processing period is shortened, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of casting molds, in particular to a structure for preventing casting flash from generating at the orifice of a bolt hole of a wear-resistant lining plate. Background Technique

[0002] The wear-resistant lining plate is used to protect the cylinder body of the autogenous mill, so that the cylinder body of the autogenous mill is not directly impacted and rubbed by the grinding media and materials. At the same time, wear-resistant lining plates with different structural forms can also be used to adjust the motion state of the grinding media, so as to enhance the crushing effect of the grinding media on the materials, help improve the grinding efficiency of the autogenous mill, increase the output, and reduce the metal consumption.

[0003] The wear-resistant lining plate itself has a bolt hole structure of 2 - 3. It is assembled and fixed with the cylinder body of the autogenous mill through bolts. Currently, resin sand manual molding is generally used for the lining plate, and the bolt hole is usually formed by casting with a separate core inserted.

[0004] When preparing a bolt hole of a similar wear-resistant lining plate by the existing process, flash in the forms of "steel bars", "cap-shaped plugs", "blind holes", etc. will be generated. Since the material used for the wear-resistant lining plate has strong toughness and high strength, it is difficult to remove the above-mentioned flash with conventional grinding tools, and cracks are likely to be generated near the orifice of the bolt hole during the process of removing the flash. Moreover, the above-mentioned grinding operation is generally carried out manually (because the shapes of the flash are diverse and the thickness has a large randomness, it is difficult to uniformly use machine grinding), resulting in low production efficiency, difficult control of product quality stability, and increased production costs.

[0005] In summary, it is very necessary to develop a structure for preventing casting flash from generating at the orifice of a bolt hole of a wear-resistant lining plate and a supporting use method, so as to effectively avoid the generation of flash or significantly reduce the difficulty of post-treatment of the flash. Content of the Utility Model

[0006] In view of the above analysis, the purpose of the utility model is to provide a structure for preventing casting flash from generating at the orifice of a bolt hole of a wear-resistant lining plate, so as to solve at least one of the problems in the prior art such as easy generation of flash at the orifice of the bolt hole of the wear-resistant lining plate, difficult treatment of the flash, easy generation of crack defects during the treatment process, long production cycle, and high treatment cost.

[0007] The purpose of the utility model is mainly achieved through the following technical solutions:

[0008] The utility model discloses a structure for preventing casting flash from generating at the orifice of a bolt hole of a wear-resistant lining plate, which is characterized in that the structure includes a bolt hole core 5, an auxiliary forming piece 7, and an upper box 1 provided with a through hole 3;

[0009] The core 5 of the bolt hole is assembled in the positioning hole 6 reserved in the lower box, and the core 5 of the bolt hole is coaxially assembled with the through hole 3 of the upper box 1; the auxiliary forming piece 7 is assembled between the end face of the core 5 of the bolt hole and the through hole 3 of the upper box 1.

[0010] Specifically, the auxiliary forming piece 7 is made of a high melting point material that is easy to process.

[0011] Specifically, the auxiliary forming piece 7 is circular, and its diameter is larger than the diameter of the upper surface of the core 5 of the bolt hole and the lower hole diameter d of the through hole 3.

[0012] Specifically, the upper hole diameter D of the through hole 3 of the upper box 1 > the lower hole diameter d, and the through hole 3 of the upper box 1 is an inverted truncated cone.

[0013] Specifically, the generatrix angle of the truncated cone is 5° to 10°.

[0014] Specifically, the core 5 of the bolt hole is a resin self-hardening sand formed body, which is obtained by a bumping process.

[0015] Specifically, the gap between the upper surface of the core 5 of the bolt hole and the lower surface of the upper box 1 is 1 to 2 mm.

[0016] Specifically, the diameter of the auxiliary forming piece 7 is 30 to 50 mm larger than the diameter of the upper surface of the core 5 of the bolt hole, and the thickness of the auxiliary forming piece 7 is 0.2 to 0.3 mm.

[0017] Specifically, the diameter of the auxiliary forming piece 7 is 15 to 25 mm larger than the lower hole diameter d of the through hole 3 of the upper box 1.

[0018] Optionally, the auxiliary forming piece 7 is a soft thin steel sheet.

[0019] Specifically, the structure is applicable to the casting of wear-resistant medium chromium steel, wear-resistant high manganese steel, and wear-resistant low alloy steel components.

[0020] Compared with the prior art, the present utility model can at least achieve one of the following beneficial effects:

[0021] 1. The structure for preventing the generation of casting flash at the bolt hole orifice of the wear-resistant lining plate disclosed by the present utility model, combined with the matching usage method, can achieve the technical effects of avoiding the generation of flash and reducing the difficulty of subsequent grinding treatment, thereby reducing the processing cost and shortening the production cycle.

[0022] For the casting mold including the structure of the present utility model, after assembly, the backfill sand, the auxiliary forming piece, and the upper surface of the core in the through hole of the upper box are tightly combined, and the diameter of the auxiliary forming piece > the lower hole diameter of the through hole > the diameter of the upper surface of the core. Therefore, during the casting process, the casting liquid cannot enter the reserved bolt hole position, avoiding the generation of casting flash.

[0023] It should be noted that the auxiliary forming sheet actually occupies the gaps into which the casting liquid would penetrate in the existing process in the form of "occupying space", artificially turning the bolt holes into blind holes. After the casting is poured, since the auxiliary forming sheet is made of easily machined material, only a pointed hammer is needed to break it open subsequently, and conventional grinding tools can be used to remove the excess material to obtain through holes for the bolt holes. In fact, after grinding, an annular part of the auxiliary forming sheet will remain in place (becoming part of the casting, invisible in appearance). Through practical tests, the above-mentioned annular residue does not affect the overall strength of the wear-resistant lining plate (casting) nor its use. It should be noted that in order to ensure a stable structure of the auxiliary forming sheet during the casting process, the material of the auxiliary forming sheet should be selected as a material with a melting point higher than the temperature of the casting liquid to avoid melting during the casting process.

[0024] In the actual casting process, strictly speaking, there is still a tiny annular gap between the upper surface of the auxiliary forming sheet and the lower surface of the upper mold box (the backfill sand in the through hole of the upper mold box is at the center of the annulus). Since the height of this gap is very small and the casting liquid is not easy to enter, flash is not easy to generate; in addition, even if flash is generated, it is very fragile and scattered and is easy to remove. In actual production, since the diameter of the lower orifice of the through hole of the upper mold box (i.e., the diameter of the lower end face of the backfill sand) is larger than the diameter of the upper surface of the core, a relatively narrow annular platform will finally be formed at the upper orifice of the bolt hole. Even if these flashes are not removed, it will not affect the fixing effect of the bolt.

[0025] In addition, since the wear-resistant lining plate is a consumable, there is no need to overly pursue the smoothness and beauty of the casting surface. On the premise of not affecting its use, reducing the processing cost and shortening the production cycle are the top priorities, and the present utility model can exactly achieve the above effects.

[0026] 2. The structure and the supporting use method disclosed by the present utility model are simple and easy to implement, and can meet the implementation requirements by modifying the existing equipment; it is suitable for factory production and wide promotion.

[0027] In the present utility model, the above-mentioned various technical solutions can also be combined with each other to achieve more preferred combined solutions. Other features and advantages of the present utility model will be described in the subsequent content, and some advantages can be made obvious from the description or understood by implementing the present utility model. The purpose and other advantages of the present utility model can be achieved and obtained from the content specifically pointed out in the text and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings are only for the purpose of showing specific embodiments and are not considered as a limitation to the present utility model. Throughout the drawings, the same reference signs represent the same components.

[0029] Figure 1 Schematic diagram of the structure (assembly state) for preventing casting flash at the orifice of the bolt hole of the wear-resistant lining plate

[0030] Reference numerals:

[0031] 1 - upper box; 2 - back filling sand; 3 - through hole; 4 - wear-resistant lining plate; 5 - bolt hole core; 6 - positioning hole; 7 - auxiliary forming piece Detailed implementation manners

[0032] The following will specifically describe the preferred embodiments of the present invention with reference to the accompanying drawings. The accompanying drawings form a part of this application and are used together with the embodiments of the present invention to explain the principle of the present invention, rather than to limit the scope of the present invention

[0033] The present invention discloses a structure for preventing casting flash at the orifice of the bolt hole of a wear-resistant lining plate, characterized in that the structure includes a bolt hole core 5, an auxiliary forming piece 7, and an upper box 1 provided with a through hole 3

[0034] The bolt hole core 5 is assembled in the positioning hole 6 reserved in the lower box, and the bolt hole core 5 is coaxially assembled with the through hole 3 of the upper box 1; the auxiliary forming piece 7 is assembled between the end faces of the bolt hole core 5 and the through hole 3 of the upper box 1

[0035] In the assembled state, the auxiliary forming piece 7 is arranged on the upper surface of the bolt hole core 5, and the through hole 3 (lower end face) of the upper box 1 is located above the auxiliary forming piece 7. The three (axis of the through hole 3, axis of the core, and center of the auxiliary forming piece 7) are preferably located on the same vertical line, which helps the tight combination of the contact surfaces (the force conduction is preferably on the same line), and can also avoid the occurrence of phenomena such as the inclination of the core during the assembly process

[0036] Specifically, the auxiliary forming piece 7 is made of a high melting point material that is easy to process. It should be noted that in order to ensure the stable structure of the auxiliary forming piece 7 during the casting process, the material should be selected with a melting point higher than the temperature of the casting liquid to avoid the melting of the auxiliary forming piece 7 during the casting process

[0037] Specifically, resin self-hardening sand (back filling sand 2) is arranged in the through hole 3. In the assembled state, the resin self-hardening sand, the auxiliary forming piece 7, and the upper surface of the bolt hole core 5 are closely attached to each other from top to bottom in sequence. For the casting mold including the above structure, after assembly, the resin self-hardening sand, the auxiliary forming piece 7, and the upper surface of the core in the through hole 3 of the upper box 1 are closely combined, and the diameter of the auxiliary forming piece 7 > the diameter of the lower orifice of the through hole 3 > the diameter of the upper surface of the core. Therefore, during the casting process, the casting liquid will not enter the reserved bolt hole position, avoiding the generation of casting flash

[0038] It should be noted that the auxiliary forming piece 7 actually occupies the gaps that the casting liquid would penetrate into in the existing process in the form of "occupying space", artificially turning the bolt hole into a blind hole. After the casting is demolded, since the auxiliary forming piece 7 is made of an easy-to-process material, subsequently, it only needs to be broken by a pointed hammer, and a conventional grinding tool can be used to remove the excess material to obtain the through hole 3 of the bolt hole. In fact, after grinding, a circular part of the auxiliary forming piece 7 will remain in place. After practical tests, the above circular residue will not affect the overall strength of the wear-resistant lining plate 4 (casting) nor its use.

[0039] Specifically, the auxiliary forming piece 7 is circular, and its diameter is larger than the diameter of the upper surface of the bolt hole core 5 and the lower hole diameter d of the through hole 3 to ensure that the auxiliary forming piece 7 can fully "occupy space" and avoid the generation of flash.

[0040] Specifically, the upper hole diameter D of the through hole 3 > the lower hole diameter d, and the through hole 3 is an inverted truncated cone. The through hole 3 in the shape of an inverted truncated cone is beneficial to the mold stripping and the sand filling operation in the subsequent backfilling sand 2 process, and can fully conduct the pressure to the auxiliary forming piece 7 to ensure the tight combination of the resin self-hardening sand (backfilling sand 2), the auxiliary forming piece 7, and the upper surface of the core.

[0041] Specifically, the generatrix angle of the truncated cone is 5° - 10°. An appropriate angle is selected according to the height of the upper box 1. The greater the height, the smaller the angle; the smaller the height, the larger the angle to ensure that the mold forming the through hole 3 can be stripped smoothly.

[0042] Specifically, the bolt hole core 5 is a resin self-hardening sand formed body obtained by the ramming process; the bolt hole core 5 is obtained by the ramming process of resin self-hardening sand, and the resin sand in the through hole 3 is added by the backfilling sand process and waits for it to naturally harden. The core obtained by the ramming process has a higher strength, and the resin self-hardening sand in the through hole 3 is slightly tamped during the backfilling sand process and waits for it to naturally harden (the strength is lower than that of the ramming core) to avoid the core below being damaged or deformed due to too large an impact force. Preferably, the material of the core (resin self-hardening sand) and the resin self-hardening sand in the through hole 3 are of the same kind.

[0043] It should be noted that the length of the core should be made as long as possible within an appropriate range so that its lower end can be firmly buried in the positioning hole 6 reserved in the lower box to prevent the core from tilting during the casting process.

[0044] Specifically, the gap between the upper surface of the bolt hole core 5 and the lower surface of the upper box 1 is 1 - 2 mm to prevent the upper box 1 from crushing the core.

[0045] Specifically, the diameter of the auxiliary forming sheet 7 is 30 - 50 mm larger than the diameter of the upper surface of the core, so as to ensure that the auxiliary forming sheet 7 can be well embedded in the casting body after pouring, preventing the generation of high-strength and high-toughness flash around the circle; the thickness of the auxiliary forming sheet 7 is 0.2 - 0.3 mm. This thickness not only meets the production requirements but also facilitates the removal of the auxiliary forming sheet 7 after pouring. If it is too thick, the strength will be too high, which is not conducive to removal.

[0046] In addition, during the actual casting process, strictly speaking, there is still a tiny annular gap between the upper surface of the auxiliary forming sheet 7 and the lower surface of the upper box 1 (the backfill sand 2 in the through hole 3 of the upper box 1 is at the center of the annulus). Since the height of this gap is very small (gap height = the gap height between the upper surface of the bolt hole core 5 and the lower surface of the upper box 1 - the thickness of the auxiliary forming sheet 7), the casting liquid is not easy to enter, so flash is not easy to generate; moreover, even if flash is generated, it is very fragile and scattered, and is easy to remove. In actual production, since the diameter of the lower orifice of the through hole 3 in the upper box 1 (i.e., the diameter of the lower end face of the backfill sand 2) is larger than the diameter of the upper surface of the core, a relatively narrow annular platform will eventually be formed at the upper orifice of the bolt hole. Even if these flashes are not removed, it will not affect the fixing effect of the bolt.

[0047] Specifically, the diameter of the auxiliary forming sheet 7 is 15 - 25 mm larger than the diameter d of the lower orifice of the through hole 3.

[0048] Optionally, the auxiliary forming sheet 7 is a soft thin steel sheet, and the material is one of common carbon steel materials such as Q235A and Q235B.

[0049] Specifically, the structure is applicable to the casting of wear-resistant medium chromium steel, wear-resistant high manganese steel, and wear-resistant low alloy steel components.

[0050] The casting mold including the structure of the present utility model can be used according to the following process:

[0051] S1: Prepare the bolt hole core 5 (manufactured by the impact process), the upper box 1 provided with the through hole 3, the lower box reserved with the positioning hole 6, and the auxiliary forming sheet 7, and assemble them as required. The specific assembly process can refer to the existing casting operation procedures; during the assembly process, it should be ensured as much as possible that the axes of the through hole 3, the center of the auxiliary forming sheet 7, and the axis of the core are on the same vertical line (as shown in Figure 1 ).

[0052] S2: Fill the resin self-hardening sand into the through hole 3 of the upper box 1 through the backfill sand process. When filling the bottom layer, it can be slightly tamped to ensure that the resin self-hardening sand, the auxiliary forming sheet 7, and the core are closely fitted, but attention should be paid to avoiding damage to the core. After filling, wait for the resin self-hardening sand to naturally harden, and then casting can be carried out;

[0053] S3: After casting, cooling, knocking out the mold, and cleaning the sand, a semi-finished component is obtained; use a pointed hammer to break the middle part of the auxiliary forming piece 7, and use a conventional grinding tool to remove the redundant auxiliary forming piece 7 to obtain a bolt hole through hole that meets the requirements, and finally obtain a casting product.

[0054] As mentioned above, it is only the preferred specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model.

Claims

1. A structure for preventing casting flash from occurring at the orifice of the bolt hole of the wear-resistant lining plate (4), characterized in that, The structure includes a bolt hole core (5), an auxiliary forming sheet (7), and an upper box (1) provided with a through hole (3); The bolt hole core (5) is assembled in a positioning hole (6) reserved in the lower box, and the bolt hole core (5) is coaxially assembled with the through hole (3) of the upper box (1); the auxiliary forming sheet (7) is assembled between the end face of the bolt hole core (5) and the through hole (3) of the upper box (1).

2. The structure according to claim 1, characterized in that, The auxiliary forming sheet (7) is circular, and its diameter is larger than the diameter of the upper surface of the bolt hole core (5) and the lower hole diameter d of the through hole (3).

3. The structure according to claim 1, characterized in that, The upper hole diameter D of the through hole (3) of the upper box (1) is greater than the lower hole diameter d, and the through hole (3) of the upper box (1) is an inverted truncated cone.

4. The structure according to claim 3, characterized in that, The generatrix angle of the truncated cone is 5° to 10°.

5. The structure according to claim 1, characterized in that, The bolt hole core (5) is a resin self-hardening sand formed body.

6. The structure according to claim 1, characterized in that, The gap between the upper surface of the bolt hole core (5) and the lower surface of the upper box (1) is 1 to 2 mm.

7. The structure according to claim 1, characterized in that, The diameter of the auxiliary forming sheet (7) is 30 to 50 mm larger than the diameter of the upper surface of the bolt hole core (5), and the thickness of the auxiliary forming sheet (7) is 0.2 to 0.3 mm.

8. The structure according to claim 1, wherein The diameter of the auxiliary forming sheet (7) is 15 to 25 mm larger than the lower hole diameter d of the through hole (3) of the upper box (1).

9. The structure according to claim 1, wherein The auxiliary forming sheet (7) is a soft thin steel sheet.

10. The structure according to claim 1, wherein The structure is applicable to the casting of wear-resistant medium chromium steel, wear-resistant high manganese steel, and wear-resistant low alloy steel components.

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