This article presents convergence analysis of analytical calculation results, simulation and production experiment of grinding balls cooling with 120 mm diameter from steel grade 70KhGS (in modeling case in Deform-3D, analogue from library was chosen - grade AISI 1070), for further heat treatment under conditions ball rolling mill of EVRAZ NTMK JSC. The analytical calculation was carried out according to well-known method, taking into account the BIO criterion and the Fourier number, and modeling was carried out using the Deform-3D software package. Start cooling temperature was set to be equivalent to balls temperature after rolling on mill which amounted to 1050 °C. Required balls temperature before hardening was determined from steel critical points and must be at least 730 °C. Balls hardenability was calculated according to ASTM A255 based on steel chemical composition. Discretion time for measuring for calculating temperatures for all research methods was 30 seconds. Nature of real ball cooling curves and simulation results in Deform-3D are identical. Results of modeling ball in Deform-3D have a greater convergence with real temperature in the middle of ball center than calculated values and less convergence on ball surface. Simulation results in Deform-3D showed averaged values between analytical calculation and physical experiment, while temperatures agreed with results of physical experiment with a fairly high reliability both on ball surface and in the middle of ball center. This is indicates possibility of using simulation process of grinding balls cooling.