An Electric Drive for a Drilling Rig Top Drive System

摘要

The operation of a drilling rig top drive system (TDS) in drilling practice at a great depth or during the construction of a drill pipe stand in the case of failure of one of two motors is considered. In the existing kinematic scheme of most domestic and foreign TDSs, the two motors are mechanically rigidly connected to the drive shaft through a gear reduction unit. It is proposed to replace the gearbox with rigid mechanical connections with a double planetary gear reducer and, thereby, ensure the operation of the electric drive with two independent mechanical channels. Such a kinematic scheme with independent mechanical channels makes it possible to provide the drilling rig operation at great depths in the case of failure of one of the drives and when constructing pipes when disassembling the drilling string. Due to a wider range of torque control for each of the two channels, in the case of failure of one of the drives, the proposed scheme implements the indicated operating modes at a reduced speed, avoiding expensive downtime. The static mechanical characteristics of the TDS for the existing and proposed systems are presented. The calculation of the mechanical converter providing the required gear ratios for each of the mechanical channels is performed. The operation of the control system and power distribution unit of two drives is considered.