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Title:
HYDRAULIC TURBINE MEMBER AND ITS WELDING METHOD
Document Type and Number:
Japanese Patent JP3386931
Kind Code:
B2
Abstract:

PURPOSE: To prevent cold cracks of a cladding layer and to improve fatigue strength, in a hydraulic turbine member with a layer of cladding by welding, by affording a specific weld layer to a residual tensile stress of the last weld layer.
CONSTITUTION: In a hydraulic turbine member with two base materials welded each other or with a cladding by welding on the surface of a base material, the weld layer is such that the surface residual stress is not more than 10kgf/ cm2 on the surface of the last weld layer. The surface of the last cladding layer after welding is given a peening treatment at 100-600°C. This peening treatment is carried out either by a cooling process after the cladding or by reheating after cooling to the room temperature. As a result, the residual stress can be reduced which is produced on the surface of the cladding member. In addition, with cold cracks prevented on the cladding layer, a fatigue strength is improved in a welding joints for members of rotary apparatus.


Inventors:
Usami, Kenichi
Takayasu, Hiroshi
Bandai, Toshihiko
Ashizawa, Koji
Nakazawa, Satoshi
Application Number:
JP16175195A
Publication Date:
March 17, 2003
Filing Date:
June 28, 1995
Export Citation:
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Assignee:
HITACHI LTD
TOKYO ELECTRIC POWER CO INC:THE
International Classes:
B24C1/10; B23K9/00; B23K9/04; B23K31/00; B24C11/00; C21D7/06; (IPC1-7): B23K31/00; B23K9/00; B23K9/04; B24C1/10; B24C11/00
Other References:
蓮井 淳・森垣 脩,現代溶接技術大系<第15巻>,日本,産報出版株式会社,1980年1月23日,P.83−85
Attorney, Agent or Firm:
作田 康夫



 
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