南京市江河圩堤及小型水库放水涵洞,多为潜孔式钢筋混凝土平面闸门,采用螺杆式启闭机。闸门用混凝土与混凝土、磨石子与磨石子止水,由于手工制作平整光洁精度差,容易漏水。螺杆式启闭机工作时螺杆需要转动平轮,螺杆力为 P_2(kg),平轮直径为 D(cm)时,会产生转动力矩为 P_2D(kg·cm),P 也称为力偶矩,此力偶矩通过螺杆的螺纹倾斜面,使螺 Nanjing River dike and small reservoir drainage culverts, mostly for the DTH reinforced concrete flat gate, the use of screw hoist. Gate with concrete and concrete, terrazzo and terrazzo water, due to the smoothness of hand-made smooth and poor precision, easy to leak. Screw hoist working screw need to turn the flat wheel, screw force P_2 (kg), flat wheel diameter D (cm), will have a rotating moment P_2D (kg · cm), P also known as the moment of force, This moment of force through the screw thread inclined surface, so screw