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DESIGN OF SINGLE-HOOD SYSTEMS
Figure 8.6 Nomenclature for major duct elements in a local exhaust ventilation system. Hoods are identified by a number and junctions by a letter.
Figure 8.7 The solvent in a vapor-phase degreaser is heated with steam or electricity and a dense vapor is formed which fills the tank. The tank is equipped with a cold-water condenser jacket. The hot vapor condenses on the jacketed side of the tank and runs back into the sump. When parts are lowered into the vapor cloud, the hot solvent vapor condenses on the cold parts and strips off the oily residue, which drops to the tank bottom. Fugitive losses from the tank are commonly controlled with lateral slot exhaust hoods. (From J. A. Murphy, Surface Preparation and Finishes for Metals. Copyright 1971. Used with permission of McGraw-Hill Book Company.)