Global Patent Index - EP 0035091 B1

EP 0035091 B1 19850410 - PROCESS FOR PRODUCING TENSION-CRACK CORROSION-RESISTANT NON MAGNETIZABLE DRILL COLLARS OF AUSTENITIC STEELS, AND APPARATUS FOR CARRYING OUT THIS PROCESS

Title (en)

PROCESS FOR PRODUCING TENSION-CRACK CORROSION-RESISTANT NON MAGNETIZABLE DRILL COLLARS OF AUSTENITIC STEELS, AND APPARATUS FOR CARRYING OUT THIS PROCESS

Publication

EP 0035091 B1 19850410 (DE)

Application

EP 80890152 A 19801219

Priority

AT 40580 A 19800125

Abstract (en)

[origin: EP0035091A1] 1. A method of manufacturing stress-corrosion-resistant non-magnetizable drill-stems made of austentic steels, characterized in that in the surface region of the drill-stems residual compressive stresses are produced by the effect of mechanically, electrically, or chemically released impact or compression energy.

IPC 1-7

C21D 7/04

IPC 8 full level

C21D 7/04 (2006.01); C21D 10/00 (2006.01)

CPC (source: EP)

C21D 7/04 (2013.01); C21D 10/00 (2013.01)

Citation (examination)

Designated contracting state (EPC)

DE FR GB IT NL

DOCDB simple family (publication)

EP 0035091 A1 19810909; EP 0035091 B1 19850410; AT 364592 B 19811027; AT A40580 A 19810315; DE 3070489 D1 19850515

DOCDB simple family (application)

EP 80890152 A 19801219; AT 40580 A 19800125; DE 3070489 T 19801219