Core release spray application method and apparatus

Abstract

A method for forming a core includes the step of providing a corebox defining in a closed configuration thereof a closed internal core-forming cavity and providing at least one external opening through the corebox into said cavity in the closed configuration (902). A core release substance is applied through the opening directly onto at least one surface of the closed core-forming cavity with the corebox in the closed configuration (904). A forming material is added to the cavity (906) followed by an addition of a core bonding agent (908). A core that has formed in said closed core-forming cavity is allowed to dry and removed from the cavity (910).

Description

FIELD OF THE INVENTION [0001] This invention relates to casting methods, including but not limited methods used to form cores for use in casting molds. BACKGROUND OF THE INVENTION [0002] A typical sand casting operation includes a series of steps or processes for forming and preparing a mold for casting. A model or pattern for a component to be cast is created and used to form a mold and various internal cores, as is known in the art. The same model is typically used to create a large number of molds. The molds and cores created are typically made by compaction of a granular material such as sand that has a high resistance to heat. The sand used to form cores is further bonded to retain its shape by an appropriate material, for example, an epoxy or phenolic material. [0003] Tooling for forming cores, or coreboxes, are typically assembled from at least two, typically three or four, separate pieces to facilitate handling and forming of the cores. In a previous process, a forming opera...

AI Technical Summary

Benefits of technology

[0006] A core-forming apparatus includes a multipiece corebox defining in a closed configuration thereof an internal cavity with at least one opening into the internal cavity in the closed configuration and an externally-supplied spray head for dispensing a core release substance. The spray head is disposed inside the corebox through the opening to spray the core release substance directly onto a surface of the internal cavity while the corebox is closed, thereby avoiding overspray onto non-core-forming surfaces of the corebox.

Problems solved by technology

A major disadvantage of the traditional spraying application for the core release substance is that much of the core releases substance is wasted.

Spraying onto the tooling uses more of the substance than is necessary for the core contact areas of the tooling, due to overspray, and yet is not effective in ensuring that the core release substance will adequately cover the intricate core forming surfaces of the tooling dies.

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