One-casting-multiple-yielding casting method of thin-walled framework castings

Abstract

The invention relates to a one-casting-multiple-yielding casting method of thin-walled framework castings. The method comprises the steps: 1) die making; 2) sand core making; 3) sprue runner setting;4) casting forming, wherein the strength of a sand core is controlled to 0.8MPa to 0.9MPa in the step 2); the strength of external shape forming sand is controlled to 0.9MPa to 1.1MPa in the step 3);the requirements on casting fluid ingredient and casting fluid temperature during casting in the casting forming in the step 4) are as follows: casting fluid is prepared from chemical ingredients in percentage by weight: 3.65% to 3.80% of C, 2.20% to 2.65% of Si, less than or equal to 0.30% of Mn, less than or equal to 0.04% of P, less than or equal to 0.012% of S, 0.035% to 0.06% of Mg, less thanor equal to 0.02% of RE, 4.50% to 4.65% of CE and the balance of Fe; the addition of a nodulizer is 1.2% to 1.30%, and the addition of an inoculant is 0.8% to 1.0%; the temperature of the casting fluid is 1,350 DEG C to 1,380 DEG C. According to the method, the production efficiency of the thin-walled framework castings can be increased while the rate of finished products of the thin-walled framework castings is increased, and the castings are free of white microstructure and defects of shrinkage porosity, slag inclusion and the like.

Description

technical field [0001] The invention relates to the casting field of castings, in particular to a casting method for thin-walled frame castings with multiple castings. Background technique [0002] Energy saving and emission reduction has become an inevitable trend of development. In order to meet the needs of social development, modern equipment has also developed towards light weight, energy saving and high efficiency in recent years. Light weight of mechanical parts is an important way to save energy. Through the research and development of liquid forming technology for precision thin-walled ductile iron castings, the forming quality of castings has been improved, and deformation or damage caused by frequent stress during work can be avoided, thereby ensuring the life of mechanical equipment and realizing the lightweight of mechanical equipment. [0003] As we all know, the Fe-C phase diagram is a double duplicate phase diagram. Under different conditions, the molten iron...

AI Technical Summary

Problems solved by technology

[0004] Because the thin-walled frame ductile iron castings are easy to form white structure (free cementite) during eutectic solidification, the structure is hard and brittle, which seriously deteriorates the mechanical properties of ductile iron and hinders the popularization and application of thin-wall ductile iron.

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