Abstract: A rock drill bit for percussive drilling, especially top hammer drilling, includes a bit head provided with front rock crushing buttons and a skirt. The bit head is provided with a number of grooves formed in the outside of the skirt and extending in the axial direction of the drill bit. Protruding lands are defined between the grooves, which likewise extend in the axial direction. Axially rearward ends of at least some of the lands are formed with retrac teeth. Each retrac tooth has a cutting edge extending along an outer circumference of the skirt.

Abstract: A drill string for percussive rock drilling includes a series of drill string components which are interconnected by thread joints. Each thread joint includes a male portion on a first of the components, and a female portion on a second of the components which receives the male portion of the first component. Each of the male and female portions includes a screw thread structure. Each of the screw thread structures includes a small-diameter thread and a large-diameter thread which are interconnected to one another by a transition thread. Each of the drill string components includes the male portion at one of its ends, and the female portion at the other of its ends.

Abstract: A rock drill bit for percussive drilling, especially top hammer drilling, includes a bit head provided with front rock crushing buttons and a skirt. The bit head is provided with a number of grooves formed in the outside of the skirt and extending in the axial direction of the drill bit. Protruding lands are defined between the grooves, which likewise extend in the axial direction. Axially rearward ends of at least some of the lands are formed with retrac teeth. Each retrac tooth has a cutting edge extending along an outer circumference of the skirt.