Atlas Model Railroad Co.

 N Scale 

The Pressure Differential (PD) covered hopper was designed as a competitor to the General American Transportation Airslide hopper in the early 1970s to transport light, powdered materials. Unlike the Airslide, which forced pressurized air up through a fabric liner to help fluidize the cargo, the PD series of hoppers applied both a positive pressure of about 15 lbs. psi above the outlets as well as a vacuum at the outlet to help draw the cargo from the car. This design was well suited to products with very small particle size, such as talc, clay, plaster and cement, which would readily foul the fabric liner in an Airslide design. In addition, since the upper hatches did not need to be opened during unloading, the PD hopper was also ideal for transporting goods where contamination by outside air, dirt or moisture could affect the load.

Features:

• Fully assembled and ready for your layout
• Accurately painted and printed
• Based on the original North American Car Company design for a 5150 cubic foot PD covered hopper, later manufactured by Trinity Industries as a 5125 cubic foot model
• Highly detailed body with many separately applied parts
• Etched metal roof walk
• Free-rolling trucks
• Factory-equipped with AccuMate® knuckle couplers
• Minimum radius: 11"

Accumate® couplers are made under license from AccuRail, Inc.