Site:               VAW alucast GmbH
                    Industriepark Staustufe
                    D-66746
                    P.O. Box 1367
                    Dillingen (Saar), Germany
                    Tel.: 6831-906-155; Fax: 6831-906-139

Date Visited:       September 20, 1995

WTEC Attendees:     T. Piwonka (report author)

Hosts:              Dr. Azita Khalili, Technical Director

BACKGROUND

VAW alucast GmbH is a greenfield foundry that began production for the first time in early 1995. It is dedicated to the production of aluminum alloy cylinder blocks and heads for Ford. The foundry is a subsidiary of VAW, a large German metal conglomerate that specializes in aluminum. Capacity is rated at two blocks or two heads every 45 seconds, with manpower at less than 65 workers per shift (many of whom are maintenance crew, since the plant is highly automated). At full production, this plant appears to be able to out-perform die casting plants that have a higher capital investment.

PROCESSING DETAILS

The plant has an in-line layout as shown in Fig. VAW.1.


Fig. VAW.1. Plant in-line layout.

Molds are made of silica sand, bonded by phenolic urethane, and assembled in "core packages." No green sand is used. The head core package consists of eight layers of cores, which are assembled by robots. For the blocks, the base and crankshaft cores, as well as the oil galleries, are set by hand; all other cores are set by robots. When the core packages are assembled, they move on to the pouring station.

VAW uses the Georg Fischer "Contact Pouring" method, in which a bottom-pour ladle contacts the top of the mold and a stopper rod is raised, releasing metal into the sprue. In the VAW gating system, the metal drops to a bottom runner, which then feeds upward through gates and risers. Electric and gas furnaces are used and the metal is Sr modified. When the mold is full, the core package is rotated so that the risers are on top. A filter is placed in the runner system.

When the castings have solidified but not cooled to room temperature, the entire mold is moved into the heat treat furnace. Here the temperature of the furnace burns off the resin binder (which provides half the heat generated to run the furnace) and while the castings are being heat treated, the sand falls off onto a conveyor belt which runs to a cooler so that the sand can be reused. At shake-out, a robot grabs each casting and manipulates it so that the remaining sand falls out of the internal passages. The castings then progress to gate and riser cut-off and rough machining before being palletized for shipping. All machining chips are recycled within the plant. Solidification modeling has been used to gate the castings. There is interest in investigating the mold-blowing mechanism.

Note that this plant was in the start-up stage at the time of the WTEC visit and that production details may well have changed within the following year. VAW has plans to open a new foundry in Mexico to serve the North American market.


Published: March 1997; WTEC Hyper-Librarian