Nobake Molding and Pouring System Eases Changes at Canadian Ferrous Foundry.

Norcast (Tritech Precision, Inc.) operates two ferrous foundries in Mont-Joli, Quebec, Canada; one producing grinding media and the other producing wearparts for the world market. Liner plates, lifter bars, grates, etc., are produced up to an individual casting weight of 3000 kg.

In 1997, the decision was made to change the molding process from green sand to furan nobake, forcing a major shift in thinking and equipment. The transformation would require the installation of a complete nobake molding and pouring system, including shakeout and sand reclamation, into the existing facility. The system selected was supplied by IMF srl, Luino, Italy, through the branch company IMF North America, Muskegon, Michigan, and uses a molding bolster plate measuring 134 x 71 in. and a pouring and cooling plate of the same size. The molding and pouring system and part of the cooling system were installed in late 1998, and commissioning of these sections occurred just before Christmas of the same year.

The system is designed to run at 6-8 average-sized molds/hr but can handle molds sized 124 x 65 x 25/25 in. at 6/hr. It can handle mold weights, including sand and casting, of up to 14 tons.

With these large poured weight molds, the mold cooling system at Norcast had to be able to carry at least 15 tons/pouring plate. Because of the alloys produced and the heavy section thickness of the castings, long cooling times are required for many of the molds. The foundry has 310 cooling positions on two levels, using nine double-deck cooling conveyors of heavy construction. The system is computer-controlled, and the computer operations are fully integrated into the foundry's main computer system. Once a mold is poured and sent to the cooling system, the required cooling time is observed and then the mold is automatically sent to shakeout.

Norcast has accomplished a great deal in a short time while executing this project, including major building extensions, a third induction melting furnace body and five new heat treat furnaces to increase its production capacity. The foundry systems give it a production capacity of 30,000 tons/yr of finished wearparts with improved dimensional accuracy and surface finish.