In Our Backflow Prevention World We Accept the Following Truths to be Self- Evident 1. A Backflow Incident Is Foreseeable, Not A Question Of If, But Rather When 2. Backflow Preventers Are A Reasonable & Reliable Method To Protect our Drinking Water From Backflow at a Cross Connection 3. An Enforceable Backflow Prevention Ordinance Is A Necessary Component In A Thorough & Complete Cross Connection Control Program 4. Backflow Preventers Only Provide Value If They are Tested and Maintained On A Regular Basis As Required In An Enforceable Ordinance 5. The Internal Backflow Preventer Check Valves Are The Key Components That Actually Prevent Backflow.
Backflow Preventer Check Valves *Recent History Of the 3 Main Differences in Backflow Preventers, The Internal Check Valves Provide the Most Important Differences 1. Pressure Drop 2. Ease of Maintenance AND The Internal Check Valves are the Components that Prevent Backflow!
Backflow Prevention Technology Update Check Valve Components Critical Engineered Parts Guiding Components* Guiding Components* 1. Center Stem Guided Poppet Check 2. Clapper Check
Evolution in Backflow Prevention Management
1960s Evolution of Backflow Preventers 2017
Evolution in Backflow Preventer Check Valves 1950 1970s Lead Weighted Checks
From Mid 1970s to Current Poppet Checks Center Stem Guided W/ Captured Springs Reversible, Replaceable Elastomer Seat Discs Without Dealing with Spring Load Bronze or Epoxy Coated Iron Disc Holder Bronze or Epoxy Coated Spring Retainer Bronze Separate Seat Ring Drop into Seat, Cover Retained Check Pressure Loss Increases as Flow Increases* Apollo (Conbraco) 40 Series Febco 825 / 805 / 806 / 826 Series Wilkins 975 / 950 Series Watts 909 / 709 Series
Mid 1990s to Current Ames / Watts Silver Bullet Clapper Style Check Design Captured Spring* Roller Fitting / Pivoting Cam Arm Guide Not Reversible, or Replaceable Discs Plastic (Noryl?) Built in Seat Threads into the body; 8 & Larger Bolted in Initial Pressure Loss Spike, Then Decreases* Ames 2000/3000/4000/5000 Series Watts 774 / 774 DCDA / 994 / 994 RPDA Series
Mid 1990 to Current Apollo 4SG / 4S Clapper Style Check Design Captured Spring Module Roller against Stationary Plate Guide Reversible, Replaceable Seat Disc Noryl Built in Seat Check Presses into Body w/ Oring Seal Low, Flat Pressure Losses All Flows* Apollo (Conbraco) 4SG, 4S Series
1990s to Current Center Stem Guided Compound Check Zurn Wilkins Check Design Captured Springs Roller Arms Against 2 Descending Ramps Reversible, Replaceable Seat Discs Noryl Built In Seat Retained in Body By Retaining Clips, Spring Fittings; 8 & Larger Bolted in Place Small Spike, Ramp Mechanical Assist for Low Pressure Losses* Zurn Wilkins 350 / 450 Series
2000 to Current Colt / Maxim Ames / Watts Check Clapper Style Check Design Retained Arm Attached to Spring Reversible, Replaceable Seat Discs Noryl Built in Seats, Check Body Check Retained in Body by set in retainer, sliding sleeve; 8 & larger Grooved Couplings & Surrounding Retainer Pressure loss - A rise at low flows, dropping lower at mid-range, then increasing* Ames Colt, Maxim 200 / 300 / 400 / 500, Watts 757, 957 Series
2009 to Current Apollo Center Stem Guided Tri-Force Check Design Captured Springs Rotating Springs Mechanical Assist Reversible, Replaceable Seat Discs Noryl, Bronze Built in Seats, Check Body Retained in Body by SS retainer, 8 & larger Bolted in Place Pressure Loss Small Rise, Then Decreasing Until Wide Open* Apollo 4A, 4An series
Check Valve Design Causes Pressure Loss Performance
What will the Next Generation of Check Valves Bring? For Backflow Prevention Program Administrators, Backflow Preventer Technicians And Backflow Preventer End Users / Owners, It s Important to Understand: 1. The Advantages & any Disadvantages of each Design 2. The Typical & Standard Maintenance Steps of Each Design 3. The Life Expectancy & so Life Cycle Costs A. Initial Purchase Price of the Assembly B. Testing, Seating Performance C. Maintenance Time & Replacement Parts Costs D. Component Durability & Assembly Life Backflow Internal Check Valves Protect the Drinking Water Supply!
Without Training, The Next Generation Might As Well be Standing on Their Heads!
Les, Thank You for your Always Willing And Valuable Guidance And, Congratulations on Your Retirement!!!!!
Thank You! Questions?