Inner cavity near-net-shaping device for micro cast-rolling additive manufacturing of large-scale special-shaped pipe

An inner cavity near-net-shaping device for micro cast-rolling additive manufacturing of large-scale special-shaped pipe, comprising:

• a main transmission assembly, an inner cavity near-net-shaping assembly and a main feed assembly, wherein
• the main transmission assembly comprises a servo motor, a servo motor base, a main transmission coupling, a first main shaft bearing seat, a second main shaft bearing seat, a first main shaft lower slider, a second main shaft lower slider, a first bearing end cover, a second bearing end cover, a third bearing end cover, a fourth bearing end cover, a first main shaft bearing, a second main shaft bearing and a hexagon head bolt;
• and the main feed assembly comprises a main guide, a ball screw, a stepping motor, a stepping motor seat, a coupling, a main feed ball screw nut, a is first ball screw nut, a second ball screw nut, a ball screw bearing seat, a ball screw bearing, a first ball screw bearing end cover and a second ball screw bearing end cover;
• and
• the inner cavity near-net-shaping assembly comprises an inner cavity mold, an expansion cylinder and an expansion push rod, the expansion cylinder is provided with a gap in a direction of a thin wall thickness thereof, an inner cavity surface of the expansion cylinder is evenly distributed along a circumferential direction thereof with an inner wedge-shaped slider, and the expansion push rod comprises a first shaft section, a second shaft section, an outer wedge-shaped slider and a third shaft section, an outer surface of the second shaft section of the expansion push rod is evenly distributed along a circumferential direction thereof with an outer wedge-shaped slider, a slope surface of the inner wedge-shaped slider is connected to a slope surface of the outer wedge-shaped slider, and the first shaft section of the expansion push rod passes through an inner diameter of the second bearing end cover, an inner diameter of the first main shaft bearing and an inner diameter of the first bearing end cover respectively and is connected to a second end of the main transmission coupling, and the third shaft section of the expansion push rod passes through an inner diameter of the third bearing end cover and an inner diameter of the fourth bearing end cover respectively and is connected to an inner diameter of the second main shaft bearing.