Series 37G Insert


The Series 37G Thimble Insert is comprised of a Series 37G Check Valve mounted in a thimble. The 37G is pre-assembled, clamped and pinned into the thimble prior to shipment. The Thimble Insert can be provided flangeless or with a circular or rectangular flange. The 37G can either face the flange or away from the flange, depending on the installation orientation and flow direction.

The flangeless Thimble Insert is inserted into a pipe and grout is injected between the pipe I.D. and thimble O.D. to provide a seal. It is also recommended to pin the Thimble Insert to the pipe. The flanged Thimble Inserts are inserted into a pipe then anchored to the concrete wall. The flange can even be fabricated with a radius to match the inside radius of the manhole. Gaskets are provided with flanged Thimble Inserts.

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 37G.

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  • Reliable backflow prevention
  • Pre-assembled, ready for installation
  • Flange or flangeless designs available
  • 100% elastomer construction eliminates maintenance
  • Will not corrode, warp or freeze open or shut
  • 1”-2” cracking pressure
  • Custom built for each application based on pressure and flow conditions
  • Available in diameters from 4" (100mm) to 96” (2400mm)