Raw materials used to make fiberglass are received via bulk over the road tankers and railroad cars. A change was made to receive a larger percentage of materials via railroad car to save on transportation costs. A potential problem was seen with railroad car unloading capacity when a second furnace was started. The plant wanted to unload railroad cars only on day shift for safety reasons and was concerned they wouldn’t be able to unload the required number of cars fast enough in the available time.

The time to stage, test samples and unload different railroad cars was time studied. A capacity model was created to predict the required time per day to unload the required number of cars based on the two furnace production forecast. It was found that the required number of cars could not be unloaded in the available time due to process constraints. The study provided the necessary data for the company to increase the unloading speed via capital improvements in the long-term and to move some materials to over the road trucks in the short-term.