Title:
METHOD OF PREVENTING INTERNAL DEFECT IN MANUFACTURE OF PIPE
Document Type and Number:
Japanese Patent JPS57199507
Kind Code:
A
Abstract:
To avoid internal faults in the manufacture of pipes, in particular on piercing or pilgering lines, the atmosphere present in the interior of a pipe ingot, which would otherwise bring about oxidation of the internal surface of the pipe, is displaced. A mixture acting with a reducing effect is introduced, after inclined rolling and subsequent descaling, into the hot pipe interior, to displace the atmosphere present by deflagatory ignition of the mixture. This creates a non-oxidizing gas atmosphere within the pipe, which is maintained for the duration of the forming process.
Inventors:
HAINTSU BARUTOKOUSUKII
Application Number:
JP5523082A
Publication Date:
December 07, 1982
Filing Date:
April 02, 1982
Export Citation:
Assignee:
MANNESMANN AG
International Classes:
B21B9/00; B21B19/14; B21B17/08; B21B23/00; B21B19/04; B21B21/00; (IPC1-7): B21B19/06; B21B21/00; B21B45/00