V-method casting process for nodular cast iron casting

Abstract

The invention belongs to the technical field of spheroidal graphite cast iron casting processing, particularly relates to a V-method casting process for a spheroidal graphite cast iron casting, and provides the following scheme aiming at the problem that the shrinkage porosity tendency of a shrinkage cavity is relatively large when a thick and large-section casting is subjected to casting processing: S1, material selection; s2, core making and modeling; s3, smelting and pouring; s4, opening the box and taking the package; s5, fine processing; according to the method, the thick and large-section ductile iron casting is cast through V-method negative pressure, during casting of the casting, by controlling the sand mold, the compactness, the number of sprues, the number of dead heads and the number of chilling blocks and selecting the proper pouring temperature, the graphitization expansion force of the casting in the solidification casting process can effectively avoid shrinkage cavity and shrinkage porosity defects, and the casting quality is improved. The negative pressure pipe is pressurized at the thick and large part of the casting, so that the cooling speed is accelerated to prevent spheroidizing recession, and meanwhile, the graphitization expansion force is reduced, so that the phenomena of shrinkage cavities and shrinkage porosity of the casting are greatly reduced.

Description

technical field [0001] The invention relates to the technical field of ductile iron casting and processing, in particular to a V method casting process for ductile iron castings. Background technique [0002] Casting is an important manufacturing method in the basic industry. Large and medium-sized cast iron parts are generally cast by resin sand process, especially thick and large section ductile iron parts become the only option for resin sand process; however, resin sand process has high dimensional accuracy, clear external contour, Castings have the advantages of smooth surface, good appearance quality, dense structure and high comprehensive quality of castings; at the same time, they have the disadvantages of high quality of raw sand, strong irritating odor at the molding and pouring site, and high cost. [0003] When casting the head plate, second plate, tail plate castings of injection molding machine, and large-section ductile iron castings of injection molding machi...

AI Technical Summary

Problems solved by technology

[0005] The invention proposes a V-method casting process for ductile iron castings, which solves the problem that the shrinkage cavity and porosity tendency is relatively large when casting thick and large cross-section castings

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