Practical importance of studying the nature of technological factors influencing the performance properties of polymeric insulation of covered conductors is found. It is shown that the structure of polyethylene insulation is very sensitive to such technological factors as the quality of raw material, the composition of the materials used, technological modes of crosslinking and extrusion of insulation covering. The given examples show the influence of technological factors on the microstructure of covering insulation, which determines its resistance to oxidation and wetting. On the basis of executed tests the experimental curves were obtained for the relationship between the main performance properties and the technological parameters, such as as cross-linking time and extrusion rate which define the degree of molecule orientation and density of the three-dimensional structure of material inside polymeric insulation of the covered conductor. A common pattern in the obtained graph functions is the increase of relative lengthening and durability of the material when linear speed of extrusion molding of the process increases.