US 4,907,640 A · Foundry gating system

Abstract

A gravity poured foundry mold having a gating system and at least one complete mold casting cavity, the gating system allowing castings to be made in more compact molds, using less metal at lower temperature, obtaining less solidification strained castings, and requiring less fettling work and less pattern work. The gating system combines the use of a strainer such as a skin-strainer with any of several fluid restraining devices including but not limited to skin-strainer covers, restraining floating pieces, non-floating restraining pieces and blind floating pieces. Also disclosed are applications in which a skin-strainer is omitted. There is disclosed apparatus which may be standardized, thereby greatly increasing the ease, accuracy and confidence with which the gating system may be used in foundries which would have available to them sets of different sizes of standardized, interchangeable and prefabricated elements as disclosed herein. Also disclosed is a combination of this gating system with in-mold metallurgical treatment. The gating system may include a straining device at the casting skin level and or one or more straining devices at upstream levels in a sprue-feeder.

Claims38

Dependent claims

An apparatus for restraining the flow of molten metal through a skin-strainer in a gating system of a foundry mold comprising:

cover means for at least partially covering the open surface of said skin-strainer, said cover means having a bottom surface opposed to said skin-strainer;
means for moving said cover means so that the rate of flow of molten metal through the skin-strainer may be varied during the process of filling and feeding the mold;
said bottom surface having projections which extend into apertures in said skin-strainer.

Dependencies are inferred from the claim text.

Foundry gating system

Life of this patent

Foundry gating system

Life of this patent

Abstract

Claims38