Compression molding remains a popular method of manufacturing plastics. The Diemolding Corporation in Canastota, New York, used compression molding to transform asbestos-containing plastic molding compound into hard plastic parts for a variety of machinery and cookware.

The Preform Molding Process and Exposure to Asbestos

In the preform department, bags and barrels of asbestos-containing plastic molding compound were ripped and pried open and dumped into a hopper, where the material was pressurized and weighed. Plastic molding compound is granular, similar to the composition of sugar, and thus difficult to handle. Opening and dumping these bags and barrels of compound created a cloud of dust which the workers inhaled. Once placed into the preform machine, the raw molding compound was compressed and punched into discs, similar to the shape of a hockey puck.

The Mold Room, Finishing Process and Exposure to Asbestos

In the mold department, the plastic molding compound discs were placed by hand into an oven and warmed. It took about two minutes for the discs to become soft and malleable. Molders then transferred the softened plastic from the oven into a mold. A hydraulic press then shaped and formed the material into plastic products. Diemolding, for example, manufactured flat irons, handles for pots and pans, and other hard plastic products. After the molding compound was pressed and had time to harden and cure, the molders removed the newly formed pieces and placed them in a tray or barrel, which was then sent to the finishing department. Before the next batch of plastic compound entered the hydraulic press, the molder used an air hose to blow out any remaining dust and debris from the mold. This was done to protect the integrity of the next product. This process was repeated every time the press was emptied, and it created asbestos dust in the breathing zone of the molders.

After the molding compound was pressed and hardened into molded products, including handles and knobs for kitchen-wares, the pieces were finished in a tumbling machine. The tumbling machine produced an action similar to that of a clothing dryer. Molded pieces were placed, by hand, into this machine, and tumbled for three to four minutes. During this process, the machine removed imperfections or excess plastic from the finished pieces. After the tumbling cycle was completed, the tumbling machine operator removed the molded plastic pieces from the machine and sent them to another finishing department employee to remove additional excess plastic by hand. The tumbling machine operator used an air hose to blow out all excess dust and debris that collected in the machine from the tumbling process. Air-hosing took place after every machine run and it generated a visible cloud of dust the tumbling machine operator inhaled.

When the tumbling process did not completely remove the rough edges left behind from the mold, additional filing of the pieces was required. Workers in the finishing department hand-filed, sanded and polished the finished pieces. Hand-filing and sanding created even more dust these workers inhaled. Finally, the end product was then packaged and shipped.

If you or a loved one has been diagnosed with mesothelioma, lung cancer or another asbestos-related disease because you worked with or around asbestos-containing plastic molding compound, please contact us today.

Additional Information

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