Retention system for retaining deck bushing of drilling machine

A drilling machine comprising:

• a frame;
• a mast system supported by the frame, the mast system including a mast weldment and a mast base plate;
• a drill string;
• a work tool coupled to the drill string;
• a deck bushing movable relative to the drill string;
• and
• a retention system for retaining the deck bushing in a raised state to facilitate an inspection and/or a replacement of the work tool from the drill string of the drilling machine, the retention system including:
• at least one retention arm assembly coupled to the mast weldment, wherein the at least one retention arm assembly has an engaging portion movable relative to the mast weldment between a lowered stowed position and a raised engaged position, wherein, when the engaging portion of the at least one retention arm assembly is in the lowered stowed position, the engaging portion of the at least one retention arm assembly is disengaged from the deck bushing and is a first distance from the mast base plate, and wherein, when the at least one retention arm assembly is in the raised engaged position, the engaging portion of the at least one retention arm assembly is a second distance from the mast base plate greater than the first distance and is engaged with the deck bushing to retain the deck bushing in the raised state to facilitate the inspection and/or the replacement of the work tool from the drill string of the drilling machine;
• and
• at least one actuator adapted to move the engaging portion of the at least one retention arm assembly between the lowered stowed position and the raised engaged position, wherein the at least one actuator is coupled to the mast weldment at a first end of the at least one actuator, and wherein the at least one actuator is coupled to the at least one retention arm assembly at a second end of the at least one actuator.

A method for retaining a deck bushing of a drilling machine, the deck bushing is movable relative to a drill string of the drilling machine, the method comprising:

• engaging a pipe positioner system of the drilling machine with the drill string of the drilling machine to guide and center a movement of the drill string along a vertical axis;
• raising the drill string such that a work tool of the drilling machine is raised above a mast base plate of the drilling machine;
• actuating at least one actuator of the drilling machine that is coupled to a mast weldment of the drilling machine at a first end of the at least one actuator;
• moving an engaging portion of at least one retention arm assembly of the drilling machine upward from a lower, stowed position wherein the engaging portion is positioned at a first distance from the mast base plate of the drilling machine to a raised engaged position wherein the engaging portion is positioned at a second distance from the mast base plate that is greater than the first distance, based on an actuation of the at least one actuator, wherein the at least one retention arm assembly is coupled to the mast weldment, and wherein the at least one actuator is coupled to the at least one retention arm assembly at a second end of the at least one actuator;
• engaging the engaging portion of the at least one retention arm assembly with the deck bushing, based on a movement of the at least one retention arm assembly to the raised engaged position;
• retaining, by the at least one retention arm assembly, the deck bushing in a raised state based on an engagement of the engaging portion of the retention arm assembly with the deck bushing to facilitate an inspection and/or a replacement of the work tool from the drill string;
• disengaging the engaging portion of the at least one retention arm assembly from the deck bushing after the inspection and/or the replacement of the work tool from the drill string;
• reseating the deck bushing on the mast base plate;
• and
• lowering the drill string of the drilling machine to a Ready-To-Drill state or a Ready-To-Tram state.