I-Butterfly valve, eyaziwa nangokuthi i-flap valve, i-valve elawulayo enesakhiwo esilula, esingase isetshenziselwe ukushintsha ukulawula okuphakathi nendawo epayipini lokucindezela okuphansi.Ivalve yovemvane isho ivalve ingxenye yayo yokuvala (i-valve disc noma ipuleti levemvane) iyidiski futhi izungeza i-valve shaft ukuze ivuleke futhi ivale.