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　　The shaftless screw conveyor is like a rotating screw shaft that drives a nut to move along its axial direction.The screw body is equivalent to the screw shaft,and the material is equivalent to the nut.When the screw body rotates continuously,the material is also transported continuously.The spiral body of the shaftless screw conveyor is a thick belt shaped blade,which is driven by the driving end shaft.There is no shaft in the middle,and the spiral body contacts the bottom lining plate of the inner wall of the casing.