Open Radial Balance.  Strong for severe induced draft service (heavy chips, sawdust, etc.). Good for wearplates and housing liners. Simplest of all centrifugal fans and least efficient. Has high mechanical strength. For a given point of rating, this fan requires medium speed. Scroll-type housing of narrow design because of required high velocity discharge. High pressure characteristics. Power rises continually to free delivery. Used primarily for material-handling applications in industrial plants. Wheel is sometimes coated with special material. This design also used for high-pressure industrial requirements. 175-172,000 CFM, Static Pressures to 50". Temperature to 1800 Fahrenheit.