METHOD OF MANUFACTURE OF DRILL RODS FOR DRILL MACHINES OF PERCUSSIVE ACTION Russian patent published in 2009 - IPC B21K21/00 E21B17/00 

FIELD: machine building.

SUBSTANCE: invention refers to machine building, particularly to production of rods for drilling machines of percussive action. The disclosed method of drill rods manufacture consists of following stages: a thick wall tube stock of specified length, thermal treatment and ratio of external diametre to wall thickness is divided to measured sections. Further curvature of measured sections is finished to a process just value; the ends and external surface of sections are subject to mechanical treatment whereupon their ends are heated and deformed to correspondingly specified temperature and wall thickness. Structure elements are cut into sections; the ends are subject to hardening, while a formed section is subject to chemical-thermal treatment by means of nitriding. The feature of the disclosed method is like follows: upon mechanical treatment of ends and external surface of the measured section an internal channel is subject to treatment with abrasive-saturated pulp by means of letting it through the channel at rate exceeding sediment formation ability of abrasive filler of pulp; and after hardening of ends the internal channel is subject to electric-chemical treatment.

EFFECT: upgraded consumer characteristics of drill rods quality in regard to transfer of percussion power, reliability and wear resistance.

3 dwg