| 摘要 |
<P>PROBLEM TO BE SOLVED: To make it difficult to cause damage to a weld zone by detoxifying martensite, produced by die burn, by post-heat treatment, in flash butt welding of a rail. <P>SOLUTION: Damage to a surface of a head away by 100-200 mm from a joint surface of a flash butt weld zone is sometimes caused in the use of the rail, or a fatigue crack is sometimes formed from a bottom surface of the rail. It is recognized that heat-affected portions exist in starting point portions of the damage and that a martensite structure is produced. In a post-heat treatment method for a stationary type flash butt weld zone of the rail, a surface of the top of the head of the rail fitted with an electrode in welding is reheated to 250-600°C, and a surface of a rail sole fitted with an electrode in welding is reheated to a temperature of ≥250°C and a solidus line temperature or below. Additionally, in a post-heat treatment method for a movable type flash butt weld zone of the rail, a surface of a rail column portion fitted with an electrode in welding is reheated to a temperature of ≥250°C and a solidus line temperature or below. Additionally, in a post-heat treatment method for a movable type flash butt weld zone of the rail, a surface of a rail column portion fitted with an electrode in welding is reheated to a temperature of ≥250°C and the solidus line temperature or below. <P>COPYRIGHT: (C)2012,JPO&INPIT |
