Lost Foam Casting Using High Performance Coating Negative Pressure Combustion Empty Shell Pouring Flow Velocity Cold Elimination of Carbon Defects

Abstract

The invention discloses a method for eliminating carbon defects in lost foam casting by using high-performance coating negative pressure combustion, empty shell, pouring air flow, and cooling. The process is as follows: after the pattern is placed in a sand box and filled with dry sand, the sand layer is sealed with a plastic film, After starting the vacuum pump, the foam pattern is ignited from the gate under negative pressure to form a complete hollow shell cavity. More than 95% of the carbon has been discharged out of the molding flask, and then molten steel is poured. When the pouring is completed, the steel When the water is in the liquid phase-solid phase coexistence temperature zone, the sealing film on the top surface of the sand box is opened or cut, and the cold air flow is sucked into the sand box to quickly cool the casting. After the pouring stops, continue to draw air for 3-6 minutes, that is The vacuum pump can be turned off. In this way, carbon emission and carbon reduction of lost foam casting can be realized. Empty shell casting can eliminate carbon defects of castings, grain refinement, easy coating, smooth surface, comprehensively improve casting quality, save energy and reduce consumption, high efficiency, high benefit, and adapt to industrialization Mass production.

Description

technical field [0001] The invention relates to lost foam casting, in particular to a method for eliminating carbon defects of castings by adopting high-performance coating negative pressure combustion hollow shell pouring air flow velocity cooling. Background technique [0002] Lost foam casting (internationally referred to as LFC) is a new casting technology representing the 21st century. It has a history of 50 years in the world, and it has been industrialized in China for almost 20 years. There are about 2,000 lost foam casting factories in the country, and It is developing at a rapid rate, but the technology is not yet mature. Even in the United States, the original invention of international lost foam casting, the problem of serious carbon defects in lost foam castings is still in the research period. Their goal is to strive for 2013 Years are maturing. The main manifestations of carbon defects are serious carburization, carbon slag pores, carbon ash wrinkling, coars...

AI Technical Summary

Problems solved by technology

This method not only has cumbersome procedures, high cost, low efficiency, and poor operational reliability—the shell is easy to break and crack, and the molten steel is easy to lift the box or burst the shell during pouring, and it is only suitable for small cast steel with special requirements for carbon addition. The production of parts cannot be applied in large-scale industrial production, and it is even more difficult to promote in China

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