The article explores the possibility of using the authors’ three new methods of unconventional extrusion of deep hollows to be used for the manufacture of spline sleeves intended for internal toothing couplings. Two invention patents, PL206466 and PL224121, and one patent application, P.416772, were used for this purpose. Numerical computations were made in the Forge®3D program for the conceptual schemes of forming sleeves. The aim of those computations was to determine the extrusion forces and to compare them with the conventional indirect and direct extrusion methods. Then, on models based on the authors’ plastic forming schemes, numerical computations were made, from which the actual energy and force parameters were determined in the form of the relationship of extrusion force versus forming tool path. Also, the degree of fill of the passes, in which spline sleeve toothing is formed, was determined.

The paper presents a comparative analysis to determine the optimal temperatures and the activation energies for various origin endo-inulinases from Aspergillus niger. The parameters were estimated based on the literature of the activity curves vs. temperature for hydrolysis of inulin. It was assumed that both the hydrolysis reaction process and the deactivation process of endo-inulinase were first-order reactions by the enzyme concentration. A mathematical model describing the effect of temperature on endo-inulinases from Aspergillus niger activity was used. Based on the comparison analysis, values of the activation energies Ea were in the range from 23:53  3:20 kJ/mol to 50:66  3:61 kJ/mol, the deactivation energies Ed were in the range from 88:42  5:03 kJ/mol to 142:87  2:75 kJ/mol and the optimum temperatures Topt were obtained in the range from 317:12  0:83 K to 332:55  0:72 for endo-inulinase A. niger.