泥门 meaning in Chinese

dump door

Technical requirement for repairing special equipment of trailing hopper suction dredgers part 4 : conical bottom valve
耙吸挖泥船专用设备修理技术要求第4部分：斜盘式泥门
Technical requirement for repairing special equipment of trailing hopper suction dredgers part 3 : box shape bottom doors
耙吸挖泥船专用设备修理技术要求第3部分：铰链式泥门
Technical requirement for repairing special equipment of trailing hopper suction dredgers part 2 : sliding bottom values
耙吸挖泥船专用设备修理技术要求第2部分：水平滑移式泥门