US 11,724,339 B2
Method for producing a drill shaft for a wet drill bit
Florian Schroeder, Maienfeld (CH); Christoph Weber, Oberaegeri (CH); and Roland Schneider, Schlins (AT)
Assigned to Hilti Aktiengesellschaft, Schaan (LI)
Appl. No. 16/472,721
Filed by Hilti Aktiengesellschaft, Schaan (LI)
PCT Filed Nov. 28, 2017, PCT No. PCT/EP2017/080665
§ 371(c)(1), (2) Date Jun. 21, 2019,
PCT Pub. No. WO2018/114242, PCT Pub. Date Jun. 28, 2018.
Claims priority of application No. 16206534 (EP), filed on Dec. 23, 2016.
Prior Publication US 2021/0129267 A1, May 6, 2021
Int. Cl. E21B 10/44 (2006.01); B23K 26/302 (2014.01); B23D 65/00 (2006.01); B21C 37/12 (2006.01); E21B 17/04 (2006.01); B23K 101/00 (2006.01)
CPC B23K 26/302 (2015.10) [B21C 37/122 (2013.01); B23D 65/00 (2013.01); E21B 10/44 (2013.01); E21B 17/041 (2020.05); B23K 2101/002 (2018.08)] 4 Claims
OG exemplary drawing
 
1. A method for producing a drill shaft for a wet drill bit, wherein the wet drill bit produces a borehole having a borehole diameter and a drilled core having a core diameter, comprising the steps of:
forming N, wherein N≥1, strip materials into a tubular body by integrally joining respective strip edges of the strip materials by N connection welds; and
providing at least one of the strip materials with at least one recess before the integrally joining, wherein the at least one recess is disposed a distance from the connection welds, wherein at least one of the at least one recess is provided on an inside of the tubular body, and wherein clean cooling and flushing fluid is transportable by the at least one of the at least one recess provided on the inside of the tubular body.