Abstract: A grease applicator for the threaded joint section of a drill shaft of a blasthole drill. The grease applicator has a grease applicator head movable to an application position adjacent the threaded section of the drill shaft by an applicator drive. The drive extends the applicator head to and extracts the applicator head from the application position. When the applicator head is at the application position, a propelling device for moving grease through the applicator head into engagement with the threaded section is activated to apply the grease to the threaded section. To distribute the grease over the threaded section, the applicator head may have a shape partially surrounding the threaded section. The threaded joint section is vertically positioned in the path of movement of the grease applicator head and the applicator head is extended by the applicator drive along a path toward the threaded section.

Abstract: A boarding stairway moves relative to fixed structure in front of it between a raised retracted position and a lowered operative position. Rollers at the top of the stairway are guided in a fixed track that is straight and vertical along most of its length from its top but curves into a short downwardly-rearwardly inclined bottom section. The stringers of the stairway rest against a roller rotatable on a fixed horizontal axis that is below and to the rear of the track; hence the bottom of the stairway swings rearward as it moves down. A counterweight that moves vertically is connected with the stairway by a cable that has a vertical front stretch extending up from the counterweight to a cable guide above the stairway and a rear oblique stretch extending down from the guide to a connection on the stairway that is spaced below its top.