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Publication date
Priority claimed from US06/449,531external-prioritypatent/US4456063A/en
Priority claimed from US06/449,376external-prioritypatent/US4502534A/en
Priority claimed from US06/449,467external-prioritypatent/US4456062A/en
Priority claimed from US06/449,375external-prioritypatent/US4444250A/en
Application filed by Hydril CofiledCriticalHydril Co
Priority claimed from PCT/US1983/001936external-prioritypatent/WO1984002374A1/en
Application grantedgrantedCritical
Publication of ATE50415T1publicationCriticalpatent/ATE50415T1/en