FIELD: drilling of wells.
SUBSTANCE: disclosed are a method and an apparatus, downhole drilling equipment and a computer-readable medium to evaluate at least one of the rotation speed at the well bottom and the torque at the well bottom for well drilling equipment when drilling the well in the rock formation. Downhole equipment comprises a rotary drive system, a drill string, a drill string bottom assembly, comprising a drill bit, an upper end connected to the rotary drive system and a speed controller configured to control the rotation speed of the upper drive by controlling its torque. Disclosed method is implemented on a computer based on a computational model based on a two-port transition matrix in the spectral region of downhole drilling equipment. In drilling (54) values of rotation speed and torque of upper drive are obtained and (55) rotation speed is calculated and torque at the well bottom by reducing width of spectral band and application of time delay to calculations, which provides cause-effect solution in time domain.
EFFECT: invention discloses a method and an apparatus for estimating the rotation speed and torque at the well bottom for downhole drilling equipment, downhole equipment and a computer program product.
18 cl, 14 dwg
