Abstract: A rock drilling bit includes at least one button having a button sidewall and button bottom, the button sidewall and the button bottom having a button sidewall geometry and a button bottom geometry, respectively. The rock drilling bit further comprises a bit body having at least one button-receiving hole having a hole sidewall and a hole bottom, the hole sidewall and the hole bottom having a hole sidewall geometry complementary to the button sidewall geometry and a hole bottom geometry, and a deformable seat compressed between the buttom bottom and the hole bottom so that the seat conforms to a hole bottom geometry and the button bottom geometry. The seat comprises tin.

Abstract: A down-the-hole hammer includes a casing and a piston movable in the casing between a lowermost operating position and an uppermost operating position. A recess is provided between the piston and the casing so that the piston and the casing define an intermediate chamber between a top end of the piston and a bottom end of the piston. A passageway is provided between a source of pressurized fluid and the intermediate chamber such that, at all positions of the piston between the lowermost and the uppermost operating positions, the source of pressurized fluid is in flow communication with the intermediate chamber through the passageway. An opening in the piston at least partially defines the passageway.

Abstract: A rock drilling bit includes at least one button having a button sidewall and button bottom, the button sidewall and the button bottom having a button sidewall geometry and a button bottom geometry, respectively. The rock drilling bit further comprises a bit body having at least one button-receiving hole having a hole sidewall and a hole bottom, the hole sidewall and the hole bottom having a hole sidewall geometry complementary to the button sidewall geometry and a hole bottom geometry, and a deformable seat compressed between the buttom bottom and the hole bottom so that the seat conforms to a hole bottom geometry and the button bottom geometry. The seat comprises tin.

Abstract: A down-the-hole hammer includes a casing and a piston movable in the casing between a lowermost operating position and an uppermost operating position. A recess is provided between the piston and the casing so that the piston and the casing define an intermediate chamber between a top end of the piston and a bottom end of the piston. A passageway is provided between a source of pressurized fluid and the intermediate chamber such that, at all positions of the piston between the lowermost and the uppermost operating positions, the source of pressurized fluid is in flow communication with the intermediate chamber through the passageway. An opening in the piston at least partially defines the passageway.

Abstract: A down-the-hole percussive hammer includes a cylindrical casing adapted to carry a drill bit, and a piston mounted in the casing for reciprocal movement to repeatedly strike the drill bit. A top sub is mounted at a rear portion of the casing, the top sub including a front face facing the piston. A feed tube is mounted to the top sub and extends forwardly along a center axis of the casing and defines an air-conducting passage. The piston includes an axial through-hole which slidably receives the feed tube. The front face and the feed tube together define a recess opening toward the piston. A removable volume-changer is insertable into the recess to vary a volume of a space in which the piston slides, and thus control a pressure at which the piston operates.