QM Series No groove bi-directional seal knife gate valve, cast iron body with the over all structure knife gate valve, including valve’ body, gate, and U-shaped flexible seal at the bottom of the body with grooves. When the valve is closed, the bottom of the gate edge contact with the seal and then compress the seal into the groove in the body and sealed gate realization; when the gate opens, separate gate from the bottom edge of the seal, seal will bounce to same level as groove, which will prevent the media sediment accumulated in the body cavity of the groove, no clogging, no residue, pipe easy to clean, so as to effectively improve the sealing effect knife gate valve to prevent leakage when the valve is closed.