Elbow precise casting mold

Abstract

The invention discloses an elbow precision casting mold. The elbow precision casting mold comprises a first elbow core pulling mold, a second elbow core pulling mold or a straight pipe core pulling mold, wherein the second elbow core pulling mold and the first elbow core pulling mold are used for respectively molding wax element models of a left elbow flange and a right elbow flange of a U-shaped flange elbow correspondingly along an axle wire; the wax element models of the left elbow flange and the right elbow flange are connected with square keys in a matched mode via stop holes, stop openings and square key slots which are matched with one another; the straight pipe core pulling mold is used for correspondingly molding a wax element model of a straight pipe flange; a molding cavity of the straight pipe core pulling mold is provided with a stop hole and a square key slot. According to the invention, when the flange elbow is cast precisely, wax elements are designed and manufactured in a separated mode, and a re-assembling technological technique is adopted, so that the problems of uneven wax element wall thickness, high rejection rate, large production field occupation area, long fusing time of a water soluble core, low productivity and relatively long elbow production cycle after water dissolving caused by crack and displacement of a water soluble core are solved.

Description

technical field [0001] The invention relates to a casting mold, in particular to a mold used for making wax pieces in investment precision casting of bent pipes. Background technique [0002] 90° stainless steel flange elbow (LB90° flange elbow) and U-shaped stainless steel flange elbow (U-shaped flange elbow) are the most common parts in heating and chemical equipment. In the prior art, the preparation process of the above-mentioned products is: forging and manufacturing flanges, pushing elbows, processing straight pipes, and finally welding and forming. This preparation process is more complicated, and the dimensional and position accuracy of the flanges is also difficult to guarantee. . [0003] Investment casting is a casting process with less cutting or no cutting. It refers to making a wax model with wax, wrapping a layer of refractory materials such as silica sol and clay on the outside, and heating the wax to melt and flow out. The empty shell formed by the refract...

AI Technical Summary

Problems solved by technology

However, due to the structure of the elbow flange, the mold design still cannot use the technology of direct core pulling or loose core pulling to produce wax parts, and the production of wax parts must also use water-soluble technology to manufacture molds; and due to the manufacturing accuracy of water-soluble wax cores, The problem of fit precision between the mold and the water-soluble, the influence of the wax injection pressure, the size and direction of the wax injection nozzle, the temperature of the wax and other factors, the water-soluble core still has fracture and displacement, which eventually leads to the melting of the water-soluble core. After the core, the wall thickness of the wax parts is uneven, and the scrap rate is high

Therefore, although the melting time of the water-soluble core is shorter than that of the integral core with the split design, the productivity is relatively low and the production cycle is still long

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