Atlas O Premier 3-Bay Centerflow Hopper

Although covered hoppers had achieved widespread use by the 1950s, it wasn’t until the following decade that they began to carry North America’s grain harvest. Prior to the 1960s, U.S. and Canadian farmers sent their wheat and other grains to market in 40’ box cars. The crop was packed in sacks or in cars with disposable grain doors that covered most of the door opening and turned the car into a rolling grain bin. Either way, loading and unloading was labor-intensive and time-consuming.

All that changed with American Car and Foundry’s (ACF’s) introduction of the Centerflow covered hopper in 1961, followed the next year by Pullman-Standard’s competitive PS-2CD covered hopper. Prior to the Centerflow, the typical covered hopper was little more than a coal hopper with a roof. Dry products such as salt were loaded through roof hatches and unloaded by gravity through doors in the floor. Like most freight cars of their era, these cars had a center sill. This support beam ran down the middle of the car between the left and right sets of unloading doors, and that led to problems in emptying the car. Typically some of the load would cake or “bridge” on the center sill, and the car would have to be vibrated to loosen the mess and achieve full unloading. Of course the vibration tended to shorten the life of the car.

The Centerflow’s key innovation was the elimination of the center sill by relocating the car’s main support beams to the bottom edge of each side. This enabled the discharge hopper doors to be located along the centerline of the car, allowing for easier, more complete unloading and banishing the problem of caking on the center sill. In addition, the car sides were curved to allow for more complete filling of the car. Stub center sills at each end provided a place to mount the trucks. The Centerflow was the first larger-capacity covered hopper designed for grain and products of similar density.

By the 1980s, ACF’s Centerflow, along with covered grain hoppers from other builders, had spelled the end of the 40’ box car in grain service. In addition to grain, Centerflows found work hauling a variety of other light to medium-density dry commodities, including salt, clay, chemicals, phosphates and other minerals.


  • Intricately Detailed Durable ABS Body
  • Metal Wheels and Axles
  • Die-Cast 4-Wheel Trucks
  • Operating Die-Cast Metal Couplers
  • Colorful, Attractive Paint Schemes
  • Fast-Angle Wheel Sets
  • Needle-Point Axles
  • 1:48 Scale Dimensions
  • Unit Measures:13 7/8” x 2 11/16” x 3 7/8”
  • Operates On O-31 Curves (3-Rail)

Check availability of this product on the Atlas Online Store

3-Rail Item# Road Name 2-Rail Item#
October 2023
3-Rail MSRP: $79.95 2-Rail MSRP: $84.95
O 3-Bay Centerflow Hopper - New Paint Schemes!
3001623 Canadian National/WC (Brown/White) 3002623
3001624 Erie Lackawanna (Gray/Black) 3002624
3001625 Georgia Pacific (Blue/White) 3002625
3001626 Ralston Purina (Gray/Red) 3002626
3001627 Sclair (Orange/White/Black) 3002627
3001628 Union Pacific/SP Patch (Gray/Black) 3002628
November 2021
3-Rail MSRP: $79.95 2-Rail MSRP: $84.95
3-Rail4-Pack MSRP: $319.80 2-Rail 4-Pack MSRP: $339.80
O 3-Bay Centerflow Hopper
3009955 BNSF (Brown/White) 3002140
3009956 Chicago & North Western (Green/Yellow) 3002141
3009957 Grand Trunk Western (Blue/White) 3002142
3009958 Missouri Pacific (Gray/Black) 3002143
3009959 Union Pacific (Gray/Black) 3002144
3009960 Vermont Railway (Yellow/Black) 3002145
3009982 Union Pacific (Gray/Black) 3002146
3009983 BNSF (Brown/White) 3002147