EP 0356417 B1 19930526 - PROCESS FOR MANUFACTURING STRESS CORROSION CRACK-RESISTANT TUBULAR BODIES, PARTICULARLY NON-MAGNETIZABLE AUSTENITIC STEEL DRILL COLLARS, AND BODIES OBTAINED THEREBY
Title (en)
PROCESS FOR MANUFACTURING STRESS CORROSION CRACK-RESISTANT TUBULAR BODIES, PARTICULARLY NON-MAGNETIZABLE AUSTENITIC STEEL DRILL COLLARS, AND BODIES OBTAINED THEREBY
Publication
Application
Priority
AT 196588 A 19880804
Abstract (en)
[origin: JPH0270884A] PURPOSE: To provide a tubular body stable in stress cracking corrosion by heating the tubular body, made of an austenitic material which is cold-worked after solution treatment and quenching at temperature for maintaining, and corresponds to a specific condition and therafter by intensifying cooling. CONSTITUTION: An object is heated to temperature equilibrium, having at least 10 deg.C temperature differential on an object wall at temperature of 200-600 deg.C, after deformation at temperature of less than 500 deg.C for increasing object strength, processing and formation of a hole after solution treatment, and quenching. Thereafter, the object is cooled by maintaining relation of (t)=10<-(> T<-638)/50> at most, under the presumption of time(t)(minute) and a temperature T ( deg.C) and remarkably removing thermal energy from this temperature or this starting temperature, at least from an inside surface of a tubular body. The cooled surface is made to show temperature decrease of at least 100 deg.C/min. down to half the value between the starting temperature and room temperature from the starting temperature.
IPC 1-7
IPC 8 full level
E21B 17/16 (2006.01); C21D 6/00 (2006.01); C21D 8/10 (2006.01); C21D 9/08 (2006.01); C21D 9/14 (2006.01)
CPC (source: EP KR US)
C21D 6/004 (2013.01 - EP US); C21D 9/00 (2013.01 - KR); C21D 9/14 (2013.01 - EP US)
Designated contracting state (EPC)
AT DE FR GB IT NL SE
DOCDB simple family (publication)
EP 0356417 A1 19900228; EP 0356417 B1 19930526; AT 392802 B 19910625; AT A196588 A 19901115; AT E89870 T1 19930615; BR 8903914 A 19900327; CA 1334572 C 19950228; DE 58904473 D1 19930701; JP H0270884 A 19900309; KR 900003387 A 19900326; MX 173658 B 19940322; NO 174163 B 19931213; NO 174163 C 19940323; NO 893152 D0 19890803; NO 893152 L 19900205; US 5026436 A 19910625
DOCDB simple family (application)
EP 89890199 A 19890727; AT 196588 A 19880804; AT 89890199 T 19890727; BR 8903914 A 19890803; CA 607498 A 19890803; DE 58904473 T 19890727; JP 20228389 A 19890803; KR 890011152 A 19890804; MX 1699389 A 19890731; NO 893152 A 19890803; US 38886889 A 19890803