Selecting the Perfect Check Valve for Your Wilden® Saniflo™ Hygienic™ Series (HS) Pump

by Wilden | Jun 02, 2025

The most hygienic applications demand the most hygienic AODD pumps.

Perfect for high cleanliness requirements, the Wilden® Saniflo™ Hygienic™ Series (HS) Pump features a free-draining flow path that enables clean-in-place (CIP) capability, eliminates areas where products can become trapped, and reduces the potential for contamination.

But for niche applications that handle shear-sensitive fluids, large solids and viscous products, the Saniflo HS pump can be equipped with three different valve types: ball, flap and mushroom.

Here’s everything you need to know about how these valves function and how to choose the best option for your application:

Transfer Shear-Sensitive Fluids with Ball Valves

As the most common check valve for all AODD pumps, the ball valve seals against the seat of the pump to keep fluid moving in only one direction. Saniflo HS pumps equipped with ball valves are ideal for shear-sensitive fluids and applications that require high suction capabilities. 

Paired with a free-draining flow path and a CIP swivel stand, the Saniflo HS pump with ball valves offers unmatched cleanability and is best suited for the following products:

  • Noodles
  • Fruit Preserves
  • Grapes for Wine
  • Salsa

Pump Larger Solids with Flap Valves

Replacing the standard check ball configuration, the flap valve operates by having a stainless steel flap valve plate that presses against the stainless steel flap valve body. This flap can open up fully inside the pump, making it suitable for applications with positive inlet pressure that require moving larger solids up to 60.3 mm (2-3/8”).

The natural gentleness of the Saniflo HS pump, coupled with flap valves, enables larger solids to be pumped easily and without damage. This includes:

  • Poultry
  • Eggs
  • Meat Products
  • Waste

Move Viscous Products with Mushroom Valves

Similar to standard check balls, mushroom valves have a rounded bulb that seals against the liquid chamber. However, it has a central stem that holds it in place, allowing the valve to move only up and down, eliminating any ball chatter.

Compared to standard check balls, Saniflo HS pumps equipped with mushroom valves are perfect for pushing viscous fluids, such as:

  • Peanut Butter
  • Molasses
  • Ketchup
  • Gels and Creams

Harnessing the Power of the Wilden Design: Patented Eccentric Valve Housing

All Wilden check valve options have one thing in common: a patented eccentric valve housing design that offers greater versatility than conventional designs.

Traditional valve housing on hygienic AODD pumps is made from a straight pipe that does not offer any wiggle room to account for the varying thicknesses and compressibility of different diaphragm options.

As such, pumps with thicker or less compressible diaphragm materials will not allow the liquid chambers and the manifolds to easily align. This increases the stress on the parts and makes assembly more difficult.

Wilden solves this issue with the patented eccentric valve housing design that features two sealing faces of the valve housing offset from each other. By spinning the eccentric valve housing, the offset distance can change and align with the natural state of the liquid chambers and the manifolds.

Because the patented valve housing design from Wilden uses standard pipe connections, it allows for upgrading existing installations of specific hygienic AODD pumps. 

Conclusion

Designed with a free-draining flow path that enables CIP capability, the Saniflo Hygienic Series (HS) Pump is an ideal pumping solution for various products and applications that require high cleanliness.

But when specific handling requirements are needed for shear-sensitive fluids, larger solids and viscous products, it’s important to consider your check valve type: ball, flap and mushroom.

With the ideal check valve option in place, the Saniflo HS can meet your application needs while maintaining the simple, reliable and efficient performance all Wilden AODD pumps are known for.

To learn more about how the Wilden Saniflo Hygienic Series (HS) Pump can refine your hygienic applications, please contact your local distributor or click here to fill out our contact form.