[en] To study the regularities of the BN type reactor fuel can distortion a method of statistical modelling has been developed. At the stage of initial data analysis the correlation of within cluster mean and standard deviations has been reduced by dissection of fuel elements profilometry data matrix in terms of the can diameter value for a number of cross sections chosen after preliminary data interpolation. Making use of orthogonal Tchebychev polynomials for the dose - temperature distortion dependence to be described results in decreasing correlation of the model explaining variables. This allows the model parameters to be evaluated by the simple regression analysis methods and ensures the model invariance under a linear transformation of irradiation parameters. 9 refs.; 1 fig.; 1 tab