Hopper car optimization 

SC Hopper Car

With a mix of jumbo and standard-sized railcars and varying capacities, the ExxonMobil Chemical Polyolefins rail fleet was difficult to load efficiently at manufacturing sites. An optimization effort was launched with three primary initiatives:

  • Match fleet size with production planning: This reorganization ensured that a shipment used all jumbo or standard-sized railcars, allowing the proper matching of railcars to production planning and fleets to be loaded at a greater overall capacity.
  • Implement spin loaders: These devices were used to increase loads by evenly spreading product into a railcar, eliminating unused hopper car space that previously existed when product was loaded and formed a conical shape.
  • Recertify rail routes: The increase in hopper car payloads resulted in a need to recertify all routes. ExxonMobil Chemical partnered with railroads to ensure all routes were recertified to handle increased loads.

These initiatives enabled Polyolefins to increase hopper car payload capacity by approximately 1,500 pounds per car and decrease fuel consumption by 136,000 gallons in 2008. The fuel savings equates to eliminating 1385 million metric tons of carbon dioxide -equivalent emissions, or the equivalent of removing about 254 cars from U.S. roads.