Gypsum mold having an internal structure ceramic body and a molding method thereof

Abstract

The present application relates to the technical field of ceramic manufacturing, and particularly relates to a gypsum mold with an internal structure ceramic body and a forming method thereof; the mold comprises an internal structure mold and an external main mold, the internal structure mold is used for manufacturing an internal structure model process green body, and the internal structure model process green body is placed in the external main mold and processed into a ceramic product green body; the present application provides a gypsum mold design and forming method of an internal structure ceramic product green body, the external main mold and the internal structure model are reasonably split, gypsum molds are respectively designed, a ceramic clay body mold with an internal structure is obtained, and a complex internal structure can be realized in a ceramic product.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ceramic manufacturing, in particular to a gypsum mold with internal structure ceramic body and a forming method thereof. BACKGROUND

[0002] Slip casting is a method of molding industrial products. It can also be used for molding slurry materials such as clay. Slip casting mainly includes slip casting mold pressing method. In the process of making ceramic slip casting mold, clay slip injection and mold pressing are usually used to obtain clay body. Clay slip injection is more popular and used more because it can form more diverse clay body.

[0003] However, the existing clay slip casting method is difficult to obtain a mold with internal structure such as cavity because the clay slip fills the inside of the mold. SUMMARY

[0004] The purpose of the present application is to provide a gypsum mold with internal structure ceramic body and a forming method thereof, which solves the following technical problems:

[0005] (1) How to obtain a ceramic product clay body with internal structure by slip casting.

[0006] The purpose of the present application can be achieved by the following technical solutions:

[0007] A gypsum mold with internal structure ceramic body, the mold includes an internal structure mold and an external main body mold, the internal structure mold is used to manufacture internal structure model process green body, the internal structure model process green body is placed in the external main body mold to process ceramic product green body.

[0008] As a further scheme of the present application: the internal structure mold includes a top mold and a bottom mold, the top mold and the bottom mold are provided with cavities on opposite sides for accommodating internal structure, the internal structure mold is provided with injection and discharge pipe and exhaust pipe respectively communicating with both ends of the cavity.

[0009] As a further scheme of the present application: the internal structure is a curved hollow pipe, and one side of the internal structure is provided with a process boss.

[0010] As a further scheme of the present application: the bottom mold is provided with a sealing boss near the injection and discharge pipe end, the bottom mold is provided with a positioning boss near the exhaust pipe end, and the top mold is provided with a positioning groove corresponding to the positioning boss.

[0011] As a further scheme of the present application: the external main body mold includes a forming upper mold and a forming lower mold, the forming lower mold is provided with a positioning groove for fixing the process boss, and the forming lower mold is provided with injection and discharge pipe at both ends.

[0012] As a further scheme of the present application: the external main mold is made of gypsum material.

[0013] The present application further discloses a forming method of a gypsum mold with an internal structure ceramic body, comprising the following steps:

[0014] Step 1: slurry casting is performed by using the internal structure mold, and an internal structure model process piece green body is obtained after pressure maintaining;

[0015] Step 2: the internal structure model process piece green body obtained in step 1 is fixed in the external main mold, and combined slurry casting is performed, and a ceramic product green body is obtained after pressure maintaining;

[0016] Step 3: the ceramic product green body in step 2 is placed in a process cutting mold for process cutting, and a ceramic product process piece clay body is obtained;

[0017] Step 4: the ceramic product process piece clay body in step 3 is reinforced, dried and surface treated, and a ceramic product clay body that can enter a kiln for firing is obtained.

[0018] As a further scheme of the present application: the process cutting mold in step 3 comprises a cutting upper mold and a cutting lower mold, the cutting lower mold is provided with a process cutting avoidance groove corresponding to the process boss, and the process boss is exposed from the process cutting avoidance groove after the cutting upper mold and the cutting lower mold are clamped.

[0019] The present application has the following beneficial effects:

[0020] 1. The present application provides a gypsum mold design and forming method of a ceramic product green body with an internal structure, the external main mold and the internal structure model are reasonably split, and gypsum molds are respectively designed, so that a ceramic clay body mold with an internal structure is obtained, and a complex internal structure can be realized in a ceramic product.

[0021] 2. The present application provides a gypsum mold design and forming method of a ceramic product green body with an internal structure, which adopts the technology of internal structure model separate forming + internal structure model and main model combined slurry casting, and in the combined slurry casting process, the reversibility of clay body and clay slurry in a certain humidity environment is fully utilized, so that the internal structure model process piece green body and the main model process piece green body are bonded into one body, the process is simple and stable.

[0022] 3. The present application provides a gypsum mold design and forming method of a ceramic product green body with an internal structure, each process piece, mold and shape correcting tooling can be designed by using 3D software, and the machining process of a three-dimensional five-axis numerical control machine tool is used, so that the production difficulty of the ceramic product can be greatly reduced, the production efficiency can be improved, and the batch production quality can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0023] The application will be further described in connection with the accompanying drawings.

[0024] Figure 1 A flow chart of the design and forming method of the gypsum mold for the green body of the ceramic product with internal structure provided by the application;

[0025] Figure 2 A schematic view of the ceramic product with internal structure;

[0026] Figure 3 A schematic view of the external body of the ceramic product with internal structure after being divided into blocks;

[0027] Figure 4 A schematic view of the internal structure of the ceramic product with internal structure after being divided into blocks;

[0028] Figure 5 A schematic view of the cross section of the ceramic product with internal structure after being divided into blocks;

[0029] Figure 6 A schematic view of the internal structure and the positioning structure

[0030] Figure 7 A schematic view of the external body and the positioning structure;

[0031] Figure 8 A schematic view of the mold structure of the internal structure;

[0032] Figure 9 A schematic view of the mold structure of the external body;

[0033] Figure 10 A schematic view of the process cutting mold;

[0034] Figure 11 A schematic view of the internal structure fixed in the external body mold;

[0035] Figure 12 A schematic view of the external body process piece fixed in the process cutting mold;

[0036] Explanation of the reference numerals:

[0037] 1. Process boss; 2. Process positioning table; 3. Positioning groove; 4. Positioning conical groove; 5. Top mold; 6. Bottom mold; 7. Positioning boss; 8. Positioning groove; 9. Injection and discharge pipe; 10. Exhaust pipe; 11. Process cutting avoidance groove; 12. Cutting groove; 13. Ceramic product clay body; 14. Internal structure piece; 15. Rib plate; 16. Forming lower mold; 17. Forming upper mold; 18. Cutting upper mold; 19. Cutting lower mold. DETAILED DESCRIPTION

[0038] Clearly, the described embodiments are merely a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort shall fall within the protection scope of the present application.

[0039] Please refer to Figures 1-12 The present application is a gypsum mold with internal structure ceramic body and a forming method thereof,

[0040] Embodiment 1

[0041] The gypsum mold with internal structure ceramic body comprises an internal structure mold and an external body mold, the internal structure mold is used to manufacture an internal structure model process green body, and the internal structure model process green body is placed in the external body mold to be processed into a ceramic product green body.

[0042] Specifically, the present application comprises an internal structure mold and an external body mold, wherein the internal structure mold is used to inject mud to obtain the internal structure 14, and the obtained internal structure 14 is called an internal structure model process green body. In order to smoothly complete the removal of the internal structure 14 and the next step processing, the obtained green body needs to have a certain strength. For this purpose, the present application adopts: 1. limiting the green body wall thickness H = H1 + M (10mm > H > 8mm), H1 is the internal structure mold wall thickness process size (10mm > H > 8mm), M is the fusion layer thickness of the mud surface layer after the mud is fused and then bonded (1mm < M < 2mm); 2. pre-drying the green body under the condition of 32℃ ~ 38℃ and relative humidity of 30% ~ 38%, so that the water content of the internal structure model process green body is reduced from 19% to 14%. Figure 5 Then the internal structure 14 is placed in the external body mold, slurry is injected, and the slurry is discharged after a certain pressure maintaining time, so as to obtain a ceramic body with internal structure. The pressure maintaining time satisfies T1 = T + T*Z*Y, T is the time required for the first slurry injection and pressure maintaining under the condition of ensuring the thickness of the mud body, Z is the number of slurry injection (80 times > Z > 90 times), Y is the water absorption loss coefficient of the gypsum mold single slurry injection (Y = 0.65%), and the principle is that the external body mold adopts a material with better water absorption than the body, such as gypsum. After a certain pressure maintaining time, the external body mold has better water absorption, so a body layer with certain strength will be formed along the inner wall of the external body mold cavity, and then the remaining slurry is discharged, so as to obtain a ceramic body with internal structure.

[0043]

[0044] ​Specifically, the inner structure mold comprises a top mold 5 and a bottom mold 6, and the top mold 5 and the bottom mold 6 are provided with cavities for accommodating the inner structure 14, and the inner structure mold is provided with injection and discharge pipes 9 and exhaust pipes 10 which are respectively communicated with both ends of the cavities.

[0045] Referring to Figure 8 , the inner structure mold of the present application has injection and discharge pipes 9 and exhaust pipes 10, wherein the injection and discharge pipes are arranged at the end of the bottom mold 6 away from the ground, i.e. the highest position of the bottom mold 6, and the exhaust pipes 10 are arranged at the end of the bottom mold 6 close to the ground, i.e. the lowest position of the bottom mold 6.

[0046] Specifically, the inner structure 14 is a curved hollow pipe, and one side of the inner structure 14 is provided with a process boss 1.

[0047] Referring to Figure 6 , the main structure of the inner structure 14 of the present application is a curved arc, and a rib plate 15 is arranged on the inner side perpendicular to the warping direction of the arc, and a group of process bosses 1 are arranged at the end of the rib plate 15 away from the arc, which are used for positioning and fixing during the injection molding of the outer main mold, so as to prevent the position of the inner structure 14 from changing during the injection molding.

[0048] Specifically, the bottom mold 6 is provided with a sealing boss at the end close to the injection and discharge pipes 9, and the bottom mold 6 is provided with a positioning boss 7 at the end close to the exhaust pipe 10, and the top mold 5 is provided with a positioning groove 8 corresponding to the positioning boss 7.

[0049] Referring to Figure 8 , the sealing boss, the positioning boss 7 and the positioning groove 8 in the present application are used for better alignment and sealing when the bottom mold 6 and the top mold 5 are clamped, and other clamping and sealing structures can also be used for this purpose.

[0050] Specifically, the outer main mold comprises a forming upper mold 17 and a forming lower mold 16, and the forming lower mold 16 is provided with a positioning groove 3 for fixing the process boss 1, and the forming lower mold 16 is provided with injection and discharge pipes at both ends.

[0051] Referring to Figure 9 , the present application is provided with injection and discharge pipes at both ends of the forming lower mold 16, and the positions of the two are based on better injection and discharge, and for this purpose, the two can also be arranged at other positions of the forming lower mold 16 or the forming upper mold 17.

[0052] Specifically, the outer main mold is made of gypsum material.

[0053] Referring to Figure 9 , in order to realize the rapid formation of a blank body with certain strength inside the outer main mold, the gypsum material with good water absorption and loose texture is selected, and for this purpose, other materials with such properties can also be used to make the outer main mold.

[0054] Specifically, the application also discloses a process cutting mold, and the process cutting mold in step 3 comprises a cutting upper mold 18 and a cutting lower mold 19, the cutting lower mold 19 is provided with a process cutting avoidance groove 11 corresponding to the process boss 1, and the process boss 1 is exposed from the process cutting avoidance groove 11 after the cutting upper mold 18 and the cutting lower mold 19 are clamped.

[0055] Referring to Figure 10 After the external main body obtained after slip casting is placed in the process cutting mold, the cutting upper mold 18 and the cutting lower mold 19 are clamped, and the position and angle of the external main body are adjusted before clamping, so that the process boss 1 is aligned with the process cutting avoidance groove 11, the process boss 1 passes through the process cutting avoidance groove 11 and is exposed after clamping, at this time, the process boss 1 can be cut through the process cutting avoidance groove 11 without damaging other parts of the external main body, so that a complete green body is obtained.

[0056] Embodiment 2

[0057] The forming method of the gypsum mold with the internal structure ceramic green body comprises the following steps:

[0058] Step 1: slip casting is performed by using an internal structure mold, and an internal structure model process piece green body is obtained after pressure maintaining;

[0059] Step 2: the internal structure model process piece green body obtained in step 1 is fixed in an external main body mold, and slip casting is performed, and a ceramic product green body is obtained after pressure maintaining;

[0060] Step 3: the ceramic product green body in step 2 is placed in a process cutting mold to perform process cutting, and a ceramic product process piece green body is obtained;

[0061] Step 4: the ceramic product process piece green body in step 3 is subjected to reinforcement, drying and surface treatment, and a ceramic product green body 13 that can enter a kiln for firing is obtained.

[0062] In the application, in step 1, according to the shape of the ceramic product model and the size and shape of the internal structure, the ceramic product model is divided into an external main body mold and a plurality of internal structure models, the gap between the non-positioning surfaces of the internal structure models is 90mm>S1>6mm, and the gap between the two positioning surfaces is 150mm>S2>20mm, so as to ensure that enough space is reserved for slurry flow during slip casting, and also prevent bonding between the internal structure pieces 14.

[0063] The gap between the non-positioning surfaces of the internal structure models is 100mm>S1>6mm Figure 5 , which refers to the space distance between the surfaces of two internal structure models after the internal structure models are installed in the main body mold, and the gap between the two positioning surfaces is 120mm>S2>20mmFigure 5 ), refers to the space distance between the adhering surface of the internal structure model and the mold after the internal structure model is installed in the main mold.

[0064] In the present application, in step 2, when designing the injection molding process piece and the injection molding gypsum mold, first, according to the placing mode of the green body when entering the kiln for firing, the horizontal and vertical dimensions of the product are distinguished and converted into horizontal and vertical process dimensions respectively, and then the process piece and the injection molding gypsum mold are designed according to the process dimensions. The thickness process dimension of the internal structure model process piece needs to leave enough space for the surface layer of the green body to be re-melted into slurry. Figure 5 The internal structure model process piece needs to be designed with a process positioning structure, the main model process piece and the internal structure model process piece need to be separated when designing the gypsum mold, and the mold needs to be designed to ensure the stability of the product.

[0065] The distinction between the horizontal and vertical dimensions is based on the fact that the shrinkage rate in the vertical direction is different from that in the horizontal direction under the action of gravity, and in order to ensure the size and shape of the product, the gravity direction is taken as the reference to distinguish all the dimensions of the product into horizontal and vertical dimensions (i.e. the gravity direction is the vertical direction).

[0066] The horizontal process dimension Axy = A / Nxy, A is the horizontal dimension, Nxy is the shrinkage rate of the green body in the horizontal direction (0.8 < Nxy < 0.89), and the vertical process dimension Bz = B / Nz, B is the vertical dimension, Nz is the shrinkage rate of the green body in the vertical direction (0.9 < Nz < 0.92).

[0067] When designing the positioning structure, a process boss 1 is designed on the internal structure model process piece, two process positioning tables 2 are designed at both ends of the external main mold process piece, a positioning groove 3 is designed on the external main mold gypsum mold to cooperate with the process boss 1 for positioning the internal structure model process piece, and two positioning conical grooves 4 are designed on the process cutting mold to cooperate with the process positioning tables 2 for positioning the external main mold green body.

[0068] As shown in Figure 8 , Figure 9 The gypsum mold includes a top mold 5 and a bottom mold 6, the bottom mold 6 is designed with a positioning boss 7, the top mold 5 is designed with a positioning groove 8 cooperating with the process boss 7, the injection and discharge pipe 9 and the exhaust pipe 10 are placed at the highest and lowest positions of the bottom mold 6, and the positions of the injection and discharge pipe 9 and the exhaust pipe connected to the product are preferably the low and high positions of the internal cavity of the product. After the product is formed by injection molding, the residual slurry in the injection hole and the exhaust hole can be easily cut without the need for hole plugging and shaping.

[0069] As shown in Figure 10As shown, the process cut-off mold, on the top die 5 process cut-off clearance groove 11 for cutting off the process boss 1, the bottom die 6 on both ends of the ceramic body to make cutting groove 12 for the blade cutting both ends of the process positioning platform 2.

[0070] In the present application, in step 3, the internal structure model is formed by internal structure mold injection, and a plurality of internal structure model green bodies are obtained after pressure maintaining for 7 minutes, the wall thickness of the structure model green body is H = H1 + M, H1 is the internal structure model wall thickness process size (10 mm > H > 8 mm), M is the thickness of the fusion layer after the surface layer of the clay body is fused into mud and then bonded (1 mm < M < 2 mm);

[0071] In the present application, in step 4, the plurality of internal structure model green bodies in step 3 are pre-dried and subjected to preliminary reinforcement treatment. The drying is preferably carried out under the conditions of temperature 35℃, relative humidity 40%, and flow rate 0, so that the water content of the internal structure model green body is reduced from 18% to 14%, so that the internal structure model green body has a certain strength while maintaining a certain humidity, and the surface of the clay body is simply treated to obtain the internal structure process piece 13.

[0072] In the present application, in step 5, the internal structure model process piece 13 obtained in step 4 is fixed in the external main body mold ( Figure 11 ), and combined injection molding is carried out. After the internal structure model process piece is positioned in the positioning structure reserved in the external main body mold, the main body model process piece is combined and injected with gypsum mold. During the combined injection molding process, the surface layer of the internal structure model process piece is diluted into mud state again by the water in the mud, and the internal structure model process piece and the main body model process piece are automatically bonded into one body in the process of water absorption of the gypsum mold. After pressure maintaining for a suitable time, a ceramic product green body is obtained.

[0073] The injection molding pressure maintaining time T1 = T + T*Z*Y, T is the initial injection molding pressure maintaining time required for the mold under the condition of ensuring the thickness of the clay body, Z is the injection molding frequency (80 times Z > 90 times), and Y is the influence coefficient of water absorption loss of single injection molding of gypsum mold on pressure maintaining time (Y = 0.65%).

[0074] In the present application, in step 6, the ceramic product green body obtained in step 5 is fixed in the positioning structure of the process cut-off mold ( Figure 10 、 Figure 12 ), and the process positioning platform 2 and the process boss 1 at both ends are cut off to obtain a complete ceramic product green body;

[0075] In the present application, in step 7, the ceramic product green body obtained in step 6 is dried, shaped and surface treated. The drying is preferably carried out under the conditions of temperature 38℃, relative humidity 32%, and flow rate 15 m / s. After the product is completely dried, the clay pores and cracks on the surface of the clay body are repaired to obtain a qualified ceramic product green body.

[0076] The working principle of the present application: the design and forming method of the gypsum mold of the ceramic product green body with internal structure in the present application adopts internal structure model to form separately, and then combines with the external main body mold structure to form by grouting, from inside to outside, so as to realize the forming of the ceramic product green body with internal structure, and provide a solution for the forming of the ceramic product green body with internal structure.

[0077] The above has carried out the detailed description to one embodiment of the present application, but the content described is only the preferred embodiment of the present application, and cannot be considered to limit the implementation range of the present application. Any equivalent change and improvement made according to the application range of the present application should still belong to the patent coverage range of the present application.

Claims

1. A forming method of a gypsum mold having an internal structure ceramic body, characterized by, The mold comprises an inner structure mold and an outer body mold, the inner structure mold is used to manufacture inner structure model process green bodies, and the inner structure model process green bodies are placed in the outer body mold to be processed into ceramic product green bodies; The inner structure part (14) is a curved hollow pipe, and one side of the inner structure part (14) is provided with a process boss (1); The main structure of the inner structure part (14) is a curved arc, and a rib plate (15) is arranged on the inner side perpendicular to the warping direction of the arc, and a group of process bosses (1) are arranged at the end of the rib plate (15) away from the arc, which are used for positioning and fixing during slurry forming of the outer body mold, so as to prevent the position of the inner structure part (14) from changing during slurry forming; The outer body mold comprises a forming upper mold (17) and a forming lower mold (16), the forming lower mold (16) is provided with a positioning groove (3) for fixing the process boss (1), and the two ends of the forming lower mold (16) are provided with a slurry injection pipe and a slurry discharge pipe; The method comprises the following steps: Step 1: slurry forming is performed by using the inner structure mold, and inner structure model process green bodies are obtained after pressure maintaining; Step 2: the inner structure model process green bodies obtained in step 1 are fixed in the outer body mold, and combined slurry forming is performed, and ceramic product green bodies are obtained after pressure maintaining; Step 3: the ceramic product green bodies in step 2 are placed in a process cutting mold for process cutting, and ceramic product process green bodies are obtained; Step 4: the ceramic product process green bodies in step 3 are reinforced, dried and surface treated, and ceramic product green bodies (13) that can enter a kiln for firing are obtained; In step 1, according to the shape and inner structure size and shape of the ceramic product model, the ceramic product model is divided into an outer body mold and a plurality of inner structure models, the gap between the non-positioning surfaces of the inner structure models is 90mm>S1>6mm, the gap between the two positioning surfaces is 150mm>S2>20mm, sufficient space is reserved for slurry flow during slurry injection, and bonding between the inner structure parts (14) is prevented; The gap between the non-positioning surfaces of the inner structure models is 100mm>S1>6mm, which refers to the space distance between the surfaces of two inner structure models after the inner structure models are arranged in the body mold, and the gap between the two positioning surfaces is 120mm>S2>20mm, which refers to the space distance between the surfaces of the inner structure models and the mold after the inner structure models are arranged in the body mold; In step 3, the inner structure models are slurry formed by using the inner structure mold, and a plurality of inner structure model green bodies are obtained after pressure maintaining for 7 minutes, the wall thickness H of the structure model green body is H1+M, H1 is the wall thickness process size of the inner structure model, and M is the fusion layer thickness after the surface layer of the green body is fused into slurry and then bonded. The process cutting mold in step 3 includes an upper cutting mold (18) and a lower cutting mold (19), the lower cutting mold (19) is provided with a process cutting avoidance groove (11) corresponding to the process boss (1), and the process boss (1) is exposed from the process cutting avoidance groove (11) after the upper cutting mold (18) and the lower cutting mold (19) are clamped. In step 5, the internal structure model process piece (13) obtained in step 4 is fixed in the external main body mold, and combined slip casting is performed, the internal structure model process piece is positioned in the positioning structure reserved in the external main body mold, and then the main body model process piece gypsum mold is combined and slip cast, in the combined slip casting process, the surface layer of the internal structure model process piece is diluted into a slurry state again by water in the slurry, and the internal structure model process piece and the main body model process piece are automatically bonded into an integrated body in the process of water absorption of the gypsum mold, and a ceramic product green body is obtained after a suitable pressure maintaining time; In step 6, the ceramic product green body obtained in step 5 is fixed in the positioning structure of the process cutting mold, and the process positioning table (2) and the process boss (1) at both ends are cut off, and a complete ceramic product green body is obtained.

2. A forming method of a gypsum mold having an internal structure ceramic body according to claim 1, characterized in that, The internal structure piece mold includes a top mold (5) and a bottom mold (6), the top mold (5) and the bottom mold (6) are provided with cavities on opposite sides for accommodating the internal structure piece (14), and the internal structure piece mold is provided with injection and discharge slurry pipes (9) and exhaust pipes (10) respectively communicating with both ends of the cavities.

3. A method of forming a gypsum mold having an internal structure ceramic body according to claim 2, characterized in that, The bottom mold (6) is provided with a sealing boss near the injection and discharge slurry pipes (9), the bottom mold (6) is provided with a positioning boss (7) near the exhaust pipe (10), and the top mold (5) is provided with a positioning groove (8) corresponding to the positioning boss (7).

4. A method of forming a gypsum mold having an internal structure ceramic body according to claim 3, characterized in that, The external main body mold is made of gypsum.

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