US 11,808,086 B2
Drill string rod
Tomas Jansson, Sandviken (SE); and Mattias Pettersson, Sandviken (SE)
Assigned to Sandvik Mining and Construction Tools AB, Sandviken (SE)
Appl. No. 17/440,421
Filed by SANDVIK MINING AND CONSTRUCTION TOOLS AB, Sandviken (SE)
PCT Filed Mar. 5, 2020, PCT No. PCT/EP2020/055758
§ 371(c)(1), (2) Date Sep. 17, 2021,
PCT Pub. No. WO2020/187575, PCT Pub. Date Sep. 24, 2020.
Prior Publication US 2022/0154538 A1, May 19, 2022
Int. Cl. E21B 17/042 (2006.01)
CPC E21B 17/0426 (2013.01) 8 Claims
OG exemplary drawing
 
1. A drill string rod arranged to form part of an assembly of connected drill string rods, the drill string rod comprising:
an elongate central rod portion extending axially between a male end and a female end, wherein the central rod portion has a hollow-cylindrical shape defined by an inner first diameter (drod) and an outer second diameter (Drod), wherein the male end includes a spigot, the spigot having a base projecting axially from a shoulder that axially separates the spigot and the central rod portion, wherein the female end includes a sleeve portion configured to fit to the spigot, wherein the base is provided with an outer thread and wherein the sleeve portion is provided with an inner thread, wherein the inner thread corresponds to the outer thread such that the inner thread of the sleeve portion is attachable to the outer thread of the base of the spigot of a further drill string rod of the assembly, a connection between the inner thread of the sleeve portion and the outer thread of the base being cylindrical, wherein, in a radial plane to the longitudinal axis of the drill string rod, the base of the spigot is defined by an outer third diameter (Dspigot) and an inner fourth diameter (dspigot) and the sleeve portion is defined by an outer fifth diameter (Dsleeve) and an inner sixth diameter (dsleeve), wherein the second diameter (Drod) >60 mm, wherein a relationship between outer diameters of the sleeve (Csleeve) and a relationship between outer diameters of the spigot (Cspigot) are defined as:

OG Complex Work Unit Math
and wherein Csleeve >2.31 or Cspigot >0.68, wherein a radial plane P extends through both the spigot and the sleeve portion along an entire length of the connection and defines the relationship between the outer diameters of the sleeve (Csleeve) and the relationship between outer diameters of the spigot (Cspigot).