Embodiments of the invention provide a housing assembly for a knife gate valve with a knife gate. The housing assembly includes a valve body defining a passageway and having a first body half and a second body half, and a one-piece liner arranged between the first body half and the second body half. A first part of the one-piece liner includes a first chest portion, a first liner bore, and a first sealing bead that is configured to engage the knife gate and extends circumferentially around the passageway. The first sealing bead defines a varying protrusion height as the first sealing bead extends around the passageway.