To assemble a short bar of small heat distortion such that a stretching work can be carried out even at a non-wide space at a front of a furnace, to easily carry out separation/division after stretching by making connection of a coupling part of the short bar to a loose structure and to make repeating use possible.
The stretching bar is assembled by a plurality of the short bars. A U-shaped female type coupling part formed with a space at a central part and having a hole inserted with an engagement pin at a side surface is provided at an end of one short bar. A male type coupling provided at an end of the other short bar and having a pin insertion hole is fitted to a central space of the female type coupling part so as to form a gap with the female type coupling. A straight pin is inserted to the pin insertion hole of the communicated female and male coupling to detachably connect them.
SHIBAMOTO SHIGERU
YAMAMOTO MASAAKI
Tomoyuki Yabuki