The calculations of floating-ring bearings based on the equation system describing two complex loaded lubricant layers. Besides, the moments of friction both on the inside and outside lubricant layer of ring must be equalized. In our work for the solution of the Reynold's equation a method of finite differences approximations on a sequence of grids is used. Availability of lubricant sources on the surfaces of a bearing and a floating-ring are taken into account. The equation of the thermal balance is solved in parallel with the calculation of trajectories of a journal and a floating-ring.