A Strange Model Pump and the Story of the Real One

(The impeller stays stationary and the housing rotates)

Strange pump

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7574 So. 74 Street Franklin, Wisconsin 53132.

While I was employed as a mechanical engineer by the Chicago, Milwaukee, St. Paul and Pacific Railroad (the Milwaukee Road) a strange pump was sent to our main shop for repairs. The pump was supposed to be a 'very good and powerful pump,' but the seals were worn out and leaked.

The centrifugal pump was of aluminum construction and the name tag was from a now unknown manufacturer in the northwest corner of the United States (either Washington, Oregon, or Idaho). The intake and pressure port was through the center of the hollow shaft, so the water was sucked in the end of the shaft and was pumped out the other end of the same shaft. The shaft, with its main impeller, stayed stationary and was held tight in the frame. The housing, with its attached pulley, was belted to an electric motor and rotated around the shaft and its stationary impeller. The outside dimension of the housing was about 36 inches.

The manufacturer was long out of business and the ceramic seals were obsolete. I made new drawings for adapting a Crane Packing Company seal to the pump castings. These housing castings had to be machined to accept the new seals.

After assembly, the pump worked fine and was sent to a Bensenville, Illinois roundhouse to provide pressure for washing diesel locomotive trucks before disassembly. I always figured that if the pump was ever discarded, I would purchase it, and power it with one of my gas engines at the shows.

The Milwaukee Road was dissolved and sold to the Soo Line. The Milwaukee shops were closed and I was laid off and found other employment. I lost track of the pump. By the time I did inquire into its whereabouts, it had been scrapped.

The strange pump stayed in my mind and I had to recreate it in a model. I made patterns and castings and machined the parts. After assembly, I piped it to a tank with hardware store plastic hose and spun the housing by hand. It pumped water!

The photo shows the model pump. I can only guess that the original purpose for a pump like this was to insert it in a pipeline to create or boost pressure. This is a speculation on my part.

Have any of the GEM readers ever seen a pump like this, or perhaps own one? If so, please let me know.