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Armstrong on Twitter: "Armstrong uses Permanent Magnet motors in all Design Envelope 4300, 4322, 4372 and 4380 pumps up to 10hp, as well as Compass H and Compass R circs. The efficiency
![Design Envelope Compass R Circulators - cross reference chart - S. A. Armstrong Limited - PDF Catalogs | Technical Documentation | Brochure Design Envelope Compass R Circulators - cross reference chart - S. A. Armstrong Limited - PDF Catalogs | Technical Documentation | Brochure](https://img.directindustry.com/pdf/repository_di/56193/design-envelope-compass-r-circulators-cross-reference-chart-783301_1mg.jpg)
Design Envelope Compass R Circulators - cross reference chart - S. A. Armstrong Limited - PDF Catalogs | Technical Documentation | Brochure
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COMPASS R20-35 and R40-45 Circulators – Armstrong Fluid Technology | 2020-07-29 | Engineered Systems Magazine
![The 2000'-diameter compass rose (world's largest), in which aircraft can land into the wind in any direction on Rogers Dry Lake bed, Dryden FRC, now NASA Neil A. Armstrong Flight Research Center, The 2000'-diameter compass rose (world's largest), in which aircraft can land into the wind in any direction on Rogers Dry Lake bed, Dryden FRC, now NASA Neil A. Armstrong Flight Research Center,](https://external-preview.redd.it/MN5Lp2OsWCQdhnWo4SEvbKcFG3p_VOVZys94VD6MlIQ.jpg?width=640&crop=smart&auto=webp&s=f3d846d85f22055c144e4abc7535696aef64ba51)