SpecialFocus

by Cope Plastics, Inc.

Coal mining can be a dangerous business. One company that specializes in advanced safety products turned to performance plastics for an armor housing on a proximity detection system used for underground mining. This system sounds audible and visual alarms if a worker comes within a certain range of equipment. The goal of this product is to reduce the instance of crushing or pinning accidents in underground environments.

The armor housing covers the electromagnetic sensor in this proximity system. It had to be strong enough to withstand rock falls, which are a chief concern in mining environments. The strength of this component was even more crucial because it serves a key role in a safety system that can save coal miners’ lives.

It also required a material that could stand up to the harsh chemicals of the mining environment, in addition to one that would machine to the tolerances needed for the application.

The part was 4″ thick, so material availability was another challenge. Finally, the housing’s design was intricate and required special equipment to machine the part per its design.

Several prototypes were designed and tested before acetal was identified as the material of choice for this application. Acetal is durable and able to resist rock falls, in addition to being highly machinable.

According to the customer, this armor housing has not had a single failure in the field. In fact, this product has been so successful that it is one of the preferred systems of the United States Mine Safety and Health Administration.

Because of the success of the acetal used for this application, more metal parts have been converted to performance plastics, improving safety and efficiency across the mining industry.