Series DB D U C K B I L L C H E C K VA LV E S Four Styles to Suit a Wide Variety of Applications The Duckbill Series valve allows material to flow through... ...and then prevents it from returning to its source. DESCRIPTION Cla-Val Series DB Duckbill Check Valves are a flexible sleeve design made of quality fabric-reinforced elastomer materials for maximum resistance to corrosion and wear caused by continuous operation with abrasive slurries, sludge, or effluent. The flexible sleeve provides maximum flow with a minimum pressure drop across the valve at all times. The principal of operation is simple. Upstream pressure in the valve forces the lips or "duckbill" apart to permit flow. As pressure or flow increases, the lips open further, allowing more flow. This feature allows solids to pass unhindered with low pressure loss. When there is backpressure or reverse flow, the lips squeeze tightly together, preventing backflow. Even with some wear, the "duckbill" check sleeve will still function including sealing around entrapped solids. The "duckbill" concept check valve has been in use for over 100 years in waterworks and commonly accepted for use in industrial process piping systems and in waste and storm water or sewer piping systems. The simple, one-piece "duckbill" sleeve eliminates moving components and intrusive body structures that create problems with conventional check valve designs. There are no mechanical parts that can freeze, corrode, bind, or otherwise inhibit smooth operation. Unlike conventional check and flap gate valves, the Cla-Val Duckbill Check valve does not require regular maintenance to replace worn seats, hinge pins, balls, or flappers. STYLES & MATERIALS Choice of (4) inlet connection styles allow Cla-Val Series DB Duckbill Check Valves to be installed in a wide variety of applications. The "duckbill" fabric-reinforced elastomer choices include: Ethylene Propylene, Viton, Buna-N, Hypalon, Butyl, Neoprene, and Natural Rubber for compatibility with most fluids. When ordering above Elastomers add first letter of the material after the model number ie: 4"-DB-N (N for Neoprene)

Elastomer Selection Guide Ethylene Propylene Rubber Most effective for applications involving potable water. waste or diluted acids. Resists solvents, halogenated hydrocarbons, oxygen. weather, ozone, oils and chemicals. Resistant to kerosene, moderate chemicals, fats, oils, grease and many hydrocarbons. Natural Rubber Good abrasion resistance, tensile strength and resilien- cy. Also suitable for applications with organic acids, alcohols, ketones and most moderate chemicals. Resists strong acids and bases, ozone, weathering, heat and oxidizing chemicals. Good resistance to animal and vegetable...

Flanged Style Duckbill Cla-Val Series DBF Duckbill Flanged Style Check Valves feature an integral, metal-backed, rubber flange for attaching directly to flangedend connections from tank or head wall. A variety of elastomers allow DBF valves to be used with many different fluids. When ordering. specify Model DBF, valve ID size, flange drilling, and add first letter of elastomer material ie: 4"-DB-N (N for Neoprene) Model DBF Dimension Chart (inches) Size ID Wt. 2.5 4 5 8 11 15 17 21 25 37 59 75 124 205 315 400 475 551 Lbs Note: Dimensions are for clearance purposes only. Actual product dimensions...

Jacket Style Duckbill Cla-Val Series DBJ Duckbill Jacket Style Check Valves feature an all-metal enclosure for the Duckbill valve installed in pipelines as a whisper quiet, non-slamming, low-maintenance, low pressure-drop check valve. A variety of elastomers allow DBJ valves to be used with many different fluids. When ordering, specify Model DBJ, nominal pipe, flange drilling, and add first letter of elastomer material ie: 4"-DBJ-N (N for Neoprene) Model DBJ Dimension Chart (inches) Size ID Note: Dimensions are for clearance purposes only. Actual product dimensions may vary based upon specific...