TECHNICAL FIELD

The present invention relates to a flexible liner for use in association with a chute for dispensing uncured or partially-cured foundry molding mix into a mold or pattern, where the curing process is completed. Such a liner is made up of an upper border region having means for affixing the liner to an interior of the chute, an intermediate region of a woven material that is adapted to line the chute with which it is used, and an outlet region.

BACKGROUND OF THE ART

The use of gaseous catalysts, and especially tertiary amines, as curing agents in the cold box process of curing phenol formaldehyde and poly-isocyanate resins is known in the art. As an example, the applicant is the owner of U.S. Pat. No. 6,686,402 to Woodson, which describes the polyurethane cold box (PUCB) process in which a large percentage of an aggregate material, such as a silica sand, is mixed with two parts of a binder system that are kept separate until the time of use. Upon being mixed, the binder mix parts begin a reaction that will form the polyurethane and the combined parts adhere to the aggregate and provide a workable foundry molding mix that is suitable to be dispensed into a core mold or pattern. Once dispensed and shaped in the core mold or pattern, a gaseous medium is blown through the shaped molding mix, hardening the foundry mix into a usable form. A typical gas used for this hardening is a tertiary amine. Sulfur dioxide or carbon dioxide are also used in other types of binder systems as the gas.

In many of the commercial applications, a mixer vessel in which the binder mix parts and the aggregate are mixed is positioned above the core machine in which the cores or patterns are formed, with a chute, between the mixer and core machine used to direct the workable foundry molding mix into the core machine. The ongoing presence of the hardening gas in the environs exposes the workable foundry mix to the hardening gas. When this occurs, the workable foundry molding mix can prematurely harden on the surfaces of the chute, etc., providing an on-going clean-up project.

It is an unmet need of the prior art to provide a flexible liner element to protect interior and exterior surface of the chute and the surroundings.

SUMMARY OF THE INVENTION

These and other unmet needs are met by a liner for protecting an interior surface of a chute for transferring the workable foundry molding mix from a mixer to a machine for molding and hardening the workable foundry molding mix, the liner comprising: an upper border portion, sized and adapted for securing the liner to an upper portion of the chute; and a body portion, having at least one panel of a flexible material, the body portion sized and adapted to line the interior surface of the chute.

In some embodiments, the upper border portion has at least one panel of a flexible material.

In some of these embodiments, the liner further comprises means for attaching the upper border portion to the upper portion of the chute, deployed on the upper border portion. In some of these embodiments, the means for attaching comprises a plurality of apertures through the upper border portion, each of the apertures positioned for passage therethrough by a one of a plurality of fasteners that attaches the chute to the mixer. In particular, the liner further comprises a plurality of reinforcing grommets, with each of the plurality of apertures provided with one of the reinforcing grommets.

In many of the embodiments, the flexible material of the body portion and, optionally, the upper border portion, is a woven fabric comprising polymeric fibers, especially a woven polymeric fabric that is further coated with a polymeric coating.

