Title:
EHRHARDT TUBE MAKING METHOD
Document Type and Number:
Japanese Patent JPH0481215
Kind Code:
A
Abstract:
PURPOSE: To manufacture a hollow tube stock excellent in surface property from an ingot as cast by giving working strain to its surface area before the ingot is heated.
CONSTITUTION: The ingot 1 as cast is a macro columnar structure and when working strain is given to its surface layer before this ingot 1 is heated, the columnar structure of the surface layer is broken and the columnar structure broken in a heating stage is recrystallized and extinguished, deformability of the surface layer is improved and therefore, crack defects become hard to occur.
Inventors:
DOHARA TADASHI
Application Number:
JP19323990A
Publication Date:
March 13, 1992
Filing Date:
July 20, 1990
Export Citation:
Assignee:
SUMITOMO METAL IND
International Classes:
B21C23/01; B21C23/20; (IPC1-7): B21C23/01; B21C23/20
Attorney, Agent or Firm:
Terutaka Hogami (1 person outside)
Next Patent: JPH0481216