This article presents the results of studies of the nickel cations diffusion mobility in an equimolar potassium borosilicate melt, which is the basis of ground enamel for insulating main pipelines. It was found that in the region of nickel oxide solubility (up to 3.0 wt% NiO), the diffusion coefficients changed by 2-4 orders of magnitude depending on the study temperature, which is explained by polymerization-depolymerization reactions in borosilicate melt. The experimental data in the lnD-T -1 coordinates are described by straight lines, which indicates the activation character of the diffusion of nickel cations. A correlation has been established between the diffusion coefficients of nickel cations and the activation energy. The dependences of ED and DNi2+ on the NiO concentration are complex and nonlinear, which may indicate changes in the structure of the K2O∙B2O3∙SiO2 melt. It has been established that the areas of nickel oxide concentrations with the maximum D values provide the greatest adhesion strength of enamel to steel, from which the main pipelines are made. The content of nickel oxide additives, providing the best adhesion of enamel to steel (0.5 and 2.25 wt.% NiO), is established, which increases the safety of the technological process of pumping oil.