Multi-speed turbine reduction gearbox system and method

A pump transmission assembly for an engine driven pump gearbox system, the pump transmission assembly comprising:

• a primary shaft configured to connect to a rotating motive source, the primary shaft having a first primary shaft gear;
• a secondary shaft configured to connect to a load, the secondary shaft having a first secondary shaft gear;
• a collar associated with the secondary shaft for selectively disengaging or engaging the primary shaft and the secondary shaft in at least one of multiple positions:
• a first engaged position where the first primary shaft gear engages the first secondary shaft gear;
• a disengaged position, being a neutral position, where the primary shaft is disengaged from the secondary shaft;
• a primary shaft brake for braking a primary shaft rotation.

A method of operating a pump gearbox system to change at least one of a speed and a torque applied to an input of a hydraulic fracing pump without utilization of a torque converter, the method comprising:

• rotating a primary shaft of the pump gearbox system,
• wherein the primary shaft of the pump gearbox system has a first primary shaft gear attached to the primary shaft, the first primary shaft gear rotated thereby;
• engaging a first secondary shaft gear of a secondary shaft with the first primary shaft gear of the primary shaft,
• wherein the secondary shaft of the pump gearbox system has the first secondary shaft gear attached to the secondary shaft and rotated thereby;
• driving, by the primary shaft, the secondary shaft in response to the engaging, the secondary shaft providing power to the input of the hydraulic fracing pump;
• translating a member attached to the secondary shaft, the translating axially shifting the secondary shaft from a first engaged position to a disengaged position;
• and
• disengaging the first primary shaft gear from the first secondary shaft gear in response to the translating, whereby the primary shaft no longer drives the secondary shaft to rotate when the secondary shaft is in the disengaged position;
• and
• rotating the secondary shaft while the secondary shaft is in the disengaged position by an electric motor to align the first primary shaft gear and a second secondary shaft gear for engaging.