Casting process of square groove shell

Abstract

The invention relates to a casting process of a square groove shell. The casting process is characterized by comprising the following specific casting processes: S1, preparing a sand mold and a mold core; s2, liquid rising; s3, mold filling; s4, crusting; s5, pressurizing; s6, maintaining pressure and crystallizing; s7, pressure relief; the clamping process blocks are integrally cast on the outer contour of the square groove shell during casting, so that the clamping process blocks are distributed in a triangular shape; when the square groove casting shell is machined, a clamp is adopted to directly clamp the clamping process block structure; the thin-wall position of the square groove casting shell does not need to be clamped, and the clamping mode can effectively prevent deformation of the square groove shell in the conventional clamping machining process and the problem that the machining precision is poor due to the fact that the machining face is changed for multiple times.

Description

Technical Field

[0001] The invention relates to the technical field of shell casting, and in particular to a casting process of a square trough shell. Background Art

[0002] In the prior art, when aluminum alloy castings are poured at low pressure, the smelted liquid metal is directly injected into the mold cavity. However, the liquid molded structure is loose and the grains are coarse, and it is easy to produce shrinkage cavities, shrinkage porosity, air holes and other defects inside, which makes the casting quality unstable and leads to low mechanical properties. Especially for large thin-walled aluminum castings, the wall thickness requirements are relatively high; For the thin-walled square groove shell structure, due to its thin wall and low self-strength; during the machining process, the requirements are high and there are many machining surfaces, and the conventional clamping method of the square groove is easy to cause the clamping deformation of the square groove product; therefore, a new square groove casting shell structure is needed to facilitate the clamping processing of the square groove. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a casting process for a square trough shell, so as to solve the problem that a general square trough shell has no casting cavity for clamping process blocks during casting, resulting in low efficiency and poor processing accuracy in subsequent processing of the product.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a casting process of a square trough shell, and its innovation lies in: the specific casting process is as follows: S1: Prepare sand mold and core: the sand mold includes a square trough outer sand mold, and the core includes a square trough inner core and an axial hole core; the square trough outer sand mold has three clamping process block casting cavities distributed in a triangular shape near the edge; a square trough shell casting cavity is formed between the square trough outer sand mold and the square trough inner core; the square trough shell casting cavity has a horizontal casting cavity and a side casting cavity, and an axial hole core is arranged at the horizontal casting cavity, which is used to form an axial hole at the horizontal casting surface of the square trough shell; S2: Liquid lifting: Before liquid lifting, the position of the axial hole core at the horizontal casting cavity is controlled, and the aluminum liquid is injected into the square trough shell casting cavity from the gate by low-pressure liquid lifting casting method; the temperature of the aluminum liquid entering the square trough shell casting cavity is 720℃-730℃, the liquid lifting speed is controlled at 50-100mm / s, and the pressurization rate is 1.27-1.75kPa / s, which is conducive to the discharge of gas in the square trough shell casting cavity; S3: Filling: The aluminum liquid rises to the top of the square trough shell casting cavity, filling the square trough shell casting cavity, and the filling time is controlled to be 40-45s, and then continues to rise to the top of the riser, filling the riser cavity, and the filling time is controlled to be 45-70s; S4: crusting: After the filling is completed, the pressure remains unchanged and the crusting time is 15-30s; S5: Pressurization: After the crusting is completed, the pressure is increased based on the filling pressure. The pressure is 1.15-1.20 kP / m 2 , the aluminum liquid compensates the shrinkage of the casting under pressure, eliminates shrinkage cavities and shrinkage, and improves density; S6: Pressure-holding crystallization: The pressure-holding time after pressurization is 10-20 minutes; S7: Pressure relief: After crystallization is completed, pressure relief is performed, and then cooling is performed for 1-2 minutes to open the mold.

[0005] Furthermore, a plurality of concave cavities are arranged in the square trough outer sand mold and the square trough inner sand mold in the casting cavity of the square trough shell, which are used to form a plurality of reinforcing protrusions on the horizontal casting surface of the square trough shell.

[0006] The advantages of the present invention are: 1) In the present invention, a clamping process block is integrally cast on the outer contour of the square groove shell during casting, so that the clamping process block is distributed in a triangular shape; when the square groove casting shell is processed, a clamp is used to directly clamp the clamping process block structure; there is no need to clamp the thin-wall position of the square groove casting shell. This clamping method can effectively prevent the deformation of the square groove shell during the conventional clamping process and the problem of poor processing accuracy caused by multiple changes in the processing surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0008] Figure 1 The present invention is a casting process flow chart of a square trough shell.

[0009] Figure 2 This is a casting roughcast diagram of a square trough shell of the present invention. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0011] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] like Figure 1 Figure 2 The casting process of a square trough shell shown in the figure is as follows: S1: Prepare sand mold and core: the sand mold includes a square trough outer sand mold, and the core includes a square trough inner core and an axial hole core; the square trough outer sand mold has three clamping process block casting cavities distributed in a triangular shape near the edge; a square trough shell casting cavity is formed between the square trough outer sand mold and the square trough inner core; the square trough shell casting cavity has a horizontal casting cavity and a side casting cavity, and an axial hole core is arranged at the horizontal casting cavity, which is used to form an axial hole at the horizontal casting surface of the square trough shell; S2: Liquid lifting: Before liquid lifting, the position of the axial hole core at the horizontal casting cavity is controlled, and the aluminum liquid is injected into the square trough shell casting cavity from the gate by low-pressure liquid lifting casting method; the temperature of the aluminum liquid entering the square trough shell casting cavity is 720℃-730℃, the liquid lifting speed is controlled at 50-100mm / s, and the pressurization rate is 1.27-1.75kPa / s, which is conducive to the discharge of gas in the square trough shell casting cavity; S3: Filling: The aluminum liquid rises to the top of the square trough shell casting cavity, filling the square trough shell casting cavity, and the filling time is controlled to be 40-45s, and then continues to rise to the top of the riser, filling the riser cavity, and the filling time is controlled to be 45-70s; S4: crusting: After the filling is completed, the pressure remains unchanged and the crusting time is 15-30s; S5: Pressurization: After the crusting is completed, the pressure is increased on the basis of the filling pressure. The pressure is 1.15-1.20kP / m2. The aluminum liquid is pressurized to compensate for the shrinkage of the casting under the action of pressure to eliminate shrinkage cavities and shrinkage and improve density. S6: Pressure-holding crystallization: The pressure-holding time after pressurization is 10-20 minutes; S7: Pressure relief: After crystallization is completed, pressure relief is performed, and then cooling is performed for 1-2 minutes to open the mold.

[0013] A plurality of concave cavities are arranged in the casting cavity of the square trough shell at the sand mold outside the square trough and at the molding sand inside the square trough, and are used to form a plurality of reinforcing protrusions on the horizontal casting surface of the square trough shell.

[0014] Those skilled in the art should understand that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, and these changes and improvements shall all fall within the scope of the present invention claimed for protection.

Claims

1. A casting process for a square trough shell, characterized in that: The specific casting process is as follows: S1: Prepare sand mold and core: the sand mold includes a square trough outer sand mold, and the core includes a square trough inner core and an axial hole core; the square trough outer sand mold has three clamping process block casting cavities distributed in a triangular shape near the edge; a square trough shell casting cavity is formed between the square trough outer sand mold and the square trough inner core; the square trough shell casting cavity has a horizontal casting cavity and a side casting cavity, and an axial hole core is arranged at the horizontal casting cavity, which is used to form an axial hole at the horizontal casting surface of the square trough shell; S2: Liquid lifting: Before liquid lifting, the position of the axial hole core at the horizontal casting cavity is controlled, and the aluminum liquid is injected into the square trough shell casting cavity from the gate by low-pressure liquid lifting casting method; the temperature of the aluminum liquid entering the square trough shell casting cavity is 720℃-730℃, the liquid lifting speed is controlled at 50-100mm / s, and the pressurization rate is 1.27-1.75kPa / s, which is conducive to the discharge of gas in the square trough shell casting cavity; S3: Filling: The aluminum liquid rises to the top of the square trough shell casting cavity, filling the square trough shell casting cavity, and the filling time is controlled to be 40-45s, and then continues to rise to the top of the riser, filling the riser cavity, and the filling time is controlled to be 45-70s; S4: crusting: After the filling is completed, the pressure remains unchanged and the crusting time is 15-30s; S5: Pressurization: After the crusting is completed, the pressure is increased based on the filling pressure. The pressure is 1.15-1.20 kP / m 2 , the aluminum liquid compensates the shrinkage of the casting under pressure, eliminates shrinkage cavities and shrinkage, and improves density; S6: Pressure-holding crystallization: The pressure-holding time after pressurization is 10-20 minutes; S7: Pressure relief: After crystallization is completed, pressure relief is performed, and then cooling is performed for 1-2 minutes to open the mold.

2. The casting process of a square trough shell according to claim 1, characterized in that: A plurality of concave cavities are arranged in the casting cavity of the square trough shell at the sand mold outside the square trough and at the molding sand inside the square trough, and are used to form a plurality of reinforcing protrusions on the horizontal casting surface of the square trough shell.

Images