Series 35-1


In some applications, a Slip-on Tideflex Duckbill Check Valve (TF-1) is not feasible because of an existing mating flange or wall thimble, or a flanged connection is preferred, or it is desired to mount the valve directly to a concrete wall. In these cases, the Series 35-1 Duckbill Check Valve is the solution.

Series 35-1 Check Valves are manufactured similarly to the Tideflex TF-1 Check Valve, with the addition of an integral elastomeric flange. The flange size drilling conforms to ANSI Class 125/150# and is also available with DIN drillings and other standard or customized drilling patterns. All Series 35-1 Check Valves are furnished complete with retaining rings for installation.

For higher backpressure ratings or to lower headloss while maintaining backpressure ratings, the Saddle Support Technology (SST) can be used in conjunction with the Series 35-1.

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  • Reliable backflow prevention
  • Minimal bottom clearance required
  • 100% elastomer construction eliminates maintenance
  • Will not corrode, warp or freeze open or shut
  • 1”-2” cracking pressure, low headloss
  • Curved bill enhances sealing around debris
  • Custom built for each application based on pressure and flow conditions
  • Available in diameters from 4" (100mm) to 72” (1800mm)