Investment casting process for thin-wall annular casing casting

Abstract

The invention provides an investment casting process for a thin-wall annular casing casting. The investment casting process comprises the following steps that a wax mold is prepared according to a design drawing, the wax mold comprises an inner wax ring and an outer wax ring which are coaxially arranged, and the outer circumferential surface of the inner wax ring is connected together through a plurality of wax rib plates; brown pulverized corundum is put into a drying oven for drying and cooled to room temperature; the brown pulverized corundum is sprayed on the inner surface of the inner waxring and the outer surface of the outer wax ring and filled between any two adjacent wax rib plates to form a casting mold component, and the casting mold component is roasted to obtain a shell; anda metal material smelted into a liquid state is poured into the shell, and the thin-wall annular casing casting is manufactured after the metal material is condensed. By the adoption of the technicalscheme, the brown pulverized corundum is baked in advance, the defect of air holes in the casting is avoided, the brown pulverized corundum and the wax mold are firmly bonded by vibrating the brown pulverized corundum and using silica sol, the shell is roasted by adopting fine-grain brown pulverized corundum, the temperature difference of a local area is prevented from being too large, the defectof cracks in the casting is avoided, and the casting quality of the casting is improved.

Description

technical field [0001] The invention relates to the technical field of casting technology, in particular to an investment casting process for thin-walled annular casing castings. Background technique [0002] Investment precision castings are widely used in the field of aerospace. In the investment casting process, it is first necessary to prepare the corresponding wax mold according to the shape characteristics of the casting to be cast, and then spray refractory sand on the surface of the wax mold, and then remove it by high-temperature roasting and melting. After the wax model is obtained, the mold shell is poured into the mold shell and melted into a liquid metal material, and the casting is obtained after the metal material is cooled and condensed. With the development of technology, people have more and more requirements for the function of casting products. Correspondingly, higher requirements are put forward for the shape and structure of casting products, such as f...

AI Technical Summary

Problems solved by technology

[0002] Investment precision castings are widely used in the field of aerospace. In the investment casting process, it is first necessary to prepare the corresponding wax mold according to the shape characteristics of the casting to be cast, and then spray refractory sand on the surface of the wax mold, and then remove it by high-temperature roasting and melting. After the wax model is obtained, the mold shell is poured into the mold shell and smelted into a liquid metal material, and the casting is obtained after the metal material is cooled and condensed. With the development of technology, people have more and more requirements for the function of casting products. Correspondingly, higher requirements are put forward for the shape and structure of casting products, such as figure 1 The thin-walled annular casing casting shown, because of its thin wall, its wall thickness features appear as corresponding narrow cavities on the corresponding mold shell, and the rest of the solid features on the mold shell are baked by sand materials. For this For thin-walled annular casing castings, if the conventional shell preparation method is used, if the sand material is mixed with water before filling, the water will enter the shell when pouring the molten metal material into the shell. In the narrow cavity, and finally into the poured metal material, air hole defects are formed on the final molded casting, which affects the performance of the casting. In addition, because the narrow cavity on the shell is extremely narrow, if the sand adjacent to it is not filled Densification will also cause part of the sand to fall into the cavity, which will affect the dimensional accuracy of the corresponding features on the final molded casting and affect the molding quality of the casting.

Images