FIELD: electrical engineering. SUBSTANCE: cable duct equipment has at least one cable duct tube made from thermosoftening plastic material with round cross-section duct which inner wall has parallel sliding ribs. Sliding ribs are produced with sliding zones in the form of screw lines with opposite direction of cooling passing with development of inner wall of duct in the form of series of waves. Length of series of waves lies within internal from 80 to 160 cm. Amplitude of these waves is less than one quarter of internal perimeter of cable duct. EFFECT: expanded application field. 7 cl, 4 dwg
