Sandvik Intellectual Property Ab

Sandvik Ab

Johan Linden

Jonas Rosen

Petri Ahola

An elongate drill component for percussive drilling includes a female threaded end having an outer diameter (Dot), a male threaded end, and a central section between the ends having an outer diameter (Doc). The outer diameter of the female threaded end is larger than the outer diameter of the central section. A through-going flushing channel includes a central flushing channel having a diameter (Dic) and thread flushing channels having a diameter (Dit). The ratio of an elastic section modulus of a threaded joint measured when the female threaded end is connected to the male threaded end of an identical component to an elastic section modulus of the central section, St/Sc, is more than 1.5 and in that a ratio of the diameter of the central flushing channel to the outer diameter of the central section, Dic/Doc is between 0.45 and 0.95.

Drill string component

A drill member for percussive rock drilling is formed by forming a compound component and friction welding the compound component to the end of a drill rod. The compound component is formed by welding a core part within a shell part and machining a thread into either the shell part (male thread) or core part (female thread). The part in which the thread is machined is formed of low alloy steel, and the other part is formed of stainless steel, wherein the thread bottom is formed of stainless steel, and the thread crests are formed of low alloy steel.

Drill member for rock drilling and a method for manufacturing the drill member

A new austenitic stainless steel alloy is provided (in wt. %) according to the following analysis:

Austenitic stainless steel with good oxidation resistance

A new austenitic stainless steel comprising in % by weight:

Growing community of inventors

Gavle, Sweden

Johan Linden