Open Bonnet Design
The SlurryFlo Control Valve open bonnet design eliminates the bonnet cavity. A longer gate section replaces the stem, which retracts past the valve’s body. As a result, the packing material seals around the gate’s perimeter (similar to a traditional knife gate valve).
SAF will specify an open bonnet when certain conditions are expected (e.g. vertical pipe with horizontally mounted valve, fluids with high viscosity, high % solids, unique fluid characteristics, etc). The design decision is application dependent. In rare cases, where the flow conditions have changed significantly, an enclosed bonnet design can be converted to open bonnet with a field retrofit kit.