Vapor Motive Company continues the development of the Unaflow steam engine based on the best designs of the past 100 years. We start from the original drawings and encompass improvements from operational experience of legacy engines, new engineering techniques, and incorporate features for modern production techniques, long-life, high degree of serviceability, and overall low life-cycle costs. |
Key aspects of VMC’s design are:

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Gray iron castings from 3D printed sand molds and cores
Customization of our design to meet vertical or horizontal frame configurations, length of stroke, steam conditions, and dead-center loading
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A variety of alternate steam temperature compensating double-beat poppet valve designs as well as low-clearance volume configurations to meet your application requirements are also available.