FIELD: manufacture of long products from powders of various, including polymeric, materials.
SUBSTANCE: can be used for the manufacture of long hollow products with various cross-sectional shapes, with area equal to or greater than the extruder cross-sectional area. A method for producing long-length hollow products from discrete and plasticized materials by compacting the material, feeding it through channels between the mandrel holder ribs into the device channel formed by a die and a mandrel, deformation processing of the material blank to form a hollow blank, moulding and calibrating the hollow blank to obtain a finished product. In this case, the deformation processing of the workpiece is carried out by giving it a draft and shear deformations by exposing it to profiled protrusions located on part of the length of the die and the mandrel with an angular step equal in the circumferential direction and the same for the die and the mandrel. Moreover, a device with profiled protrusions in the form of helical protrusions is used, the hollow workpiece is upset in directions orthogonal to the surfaces of the hollow workpiece and opposite to each other in the direction with a displacement in the circumferential direction relative to each other up to half the angular pitch of the helical protrusions, and opposite rotations are imparted to its inner and outer surfaces in the process of moving the hollow workpiece along the channel by screw protrusions, causing shear deformations in the material of the hollow billet, reaching maximum values in the areas of the hollow billet, where the distance between its surfaces is minimal. Therewith, the area of the deforming channel in the annular sections orthogonal to its axis is 10-15% less than the total area of the mandrel holder channels. Moreover, the maximum values of the sums of deformations given to the workpiece are provided in those areas of the workpiece where the material was cut by the ribs of the mandrel holder when it was fed into the channel of the device, and the deformation processing is carried out along the channel in several successive stages, while at each subsequent stage the workpiece areas with the maximum values of the sums deformations are displaced in the circumferential direction relative to the indicated zones in the previous stage by an angle of up to half the circumferential step between the indicated areas.
EFFECT: possibility of obtaining long-length hollow products from discrete and plasticized materials with a non-porous, defect-free and homogeneous material structure, the maximum cross-sectional area of which is equal to or greater than the cross-sectional area of the screw or plunger path of the extrusion press.
3 cl, 18 dwg
