A feeding screw machine for feeding a processing screw machine having - a housing, - at least two housing bores (47, 48) formed in the housing and penetrating each other, - a supply opening formed in the housing for supplying material into the at least two housing bores (47, 48), - a feeding opening formed in the housing for feeding the material to a processing screw machine, and - at least two screw shafts (49, 50) rotatably arranged in the at least two housing bores (47, 48) for conveying the material in a conveying direction from the supply opening to the feeding opening, -- wherein the at least two housing bores (47, 48) and the at least two screw shafts (49, 50) in a respective cross-sectional plane (E(x)) define a free volume V(x) = A(x) · H(x), wherein A(x) describes a free cross-sectional area in the cross-sectional plane (E(x)), H(x) describes a pitch of the screw shafts (49, 50) on the basis of an inclination (S(x)) in the cross-section plane (E(x)), and x describes a conveying point in the conveying direction, -- wherein, for continuous compression of the material, the free volume V(x) decreases monotonically in the conveying direction at least in some regions, and -- wherein a screw outer diameter (D a (x)) of the at least two screw shafts (49, 50) decreases at least regionally in the conveying direction, characterized in that a tapering K = D a x 1 2 L · D a x 3 is defined for a conical configuration of the at least two screw shafts (49, 50), wherein 0.05 ≤ K ≤ 1 applies, wherein D a (x 1) describes the screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 1 which corresponds to a screw shaft start of the at least two screw shafts (49, 50), D a (x 3) describes a screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 3 which corresponds to a screw shaft end of the at least two screw shafts (49, 50), and L describes a length of the at least two screw shafts (49, 50). - a housing, - at least two housing bores (47, 48) formed in the housing and penetrating each other, - a supply opening formed in the housing for supplying material into the at least two housing bores (47, 48), - a feeding opening formed in the housing for feeding the material to a processing screw machine, and - at least two screw shafts (49, 50) rotatably arranged in the at least two housing bores (47, 48) for conveying the material in a conveying direction from the supply opening to the feeding opening, -- wherein the at least two housing bores (47, 48) and the at least two screw shafts (49, 50) in a respective cross-sectional plane (E(x)) define a free volume V(x) = A(x) · H(x), wherein A(x) describes a free cross-sectional area in the cross-sectional plane (E(x)), H(x) describes a pitch of the screw shafts (49, 50) on the basis of an inclination (S(x)) in the cross-section plane (E(x)), and x describes a conveying point in the conveying direction, -- wherein, for continuous compression of the material, the free volume V(x) decreases monotonically in the conveying direction at least in some regions, and -- wherein a screw outer diameter (D a (x)) of the at least two screw shafts (49, 50) decreases at least regionally in the conveying direction, characterized in that a tapering K = D a x 1 2 L · D a x 3 is defined for a conical configuration of the at least two screw shafts (49, 50), wherein 0.05 ≤ K ≤ 1 applies, wherein D a (x 1) describes the screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 1 which corresponds to a screw shaft start of the at least two screw shafts (49, 50), D a (x 3) describes a screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 3 which corresponds to a screw shaft end of the at least two screw shafts (49, 50), and L describes a length of the at least two screw shafts (49, 50). -- wherein the at least two housing bores (47, 48) and the at least two screw shafts (49, 50) in a respective cross-sectional plane (E(x)) define a free volume V(x) = A(x) · H(x), wherein A(x) describes a free cross-sectional area in the cross-sectional plane (E(x)), H(x) describes a pitch of the screw shafts (49, 50) on the basis of an inclination (S(x)) in the cross-section plane (E(x)), and x describes a conveying point in the conveying direction, A(x) describes a free cross-sectional area in the cross-sectional plane (E(x)), H(x) describes a pitch of the screw shafts (49, 50) on the basis of an inclination (S(x)) in the cross-section plane (E(x)), and x describes a conveying point in the conveying direction, -- wherein, for continuous compression of the material, the free volume V(x) decreases monotonically in the conveying direction at least in some regions, and -- wherein a screw outer diameter (D a (x)) of the at least two screw shafts (49, 50) decreases at least regionally in the conveying direction, that a tapering K = D a x 1 2 L · D a x 3 is defined for a conical configuration of the at least two screw shafts (49, 50), wherein 0.05 ≤ K ≤ 1 applies, wherein D a (x 1) describes the screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 1 which corresponds to a screw shaft start of the at least two screw shafts (49, 50), D a (x 3) describes a screw outer diameter of the at least two screw shafts (49, 50) at a conveying point x 3 which corresponds to a screw shaft end of the at least two screw shafts (49, 50), and L describes a length of the at least two screw shafts (49, 50).