FIELD: metallurgy.
SUBSTANCE: tool 10 comprises body 20, rod 30, expansion element 50 and end assembly 60. Said expansion element 50 and end assembly 60 serve to contract rod 30 axially. Said expansion element 50 can be jointed with rod 30 and/or body 20 by means of one or several uncoupling elements 62. End assembly 60 may comprises spring elements 64 to apply axial force to expansion element 50. Rod 30 may incorporate various means for reducing strains nearby rod 30.
EFFECT: higher wear resistance.
15 cl, 10 dwg, 1 ex
