To prevent the generation of cracks and the entry of combustion product from the space of a joint by providing, a fluid transport pipe coat part with a circular arc shape in section, an inclination on an outer surface so as to become gradually thick from a lower end side to an upper end side and an engaging protrusion on the outer surface side edge part in the upper end and tapered parts on both side surfaces.
A pipe block body 10 is formed with a fluid transport pipe coat part with a circular arc shape in section with which two fluid transport pipes 11 are coated in parallel. The outer surface 14 thereof is provided with an inclination so as to become gradually thick from a lower end side to an upper end side. A thick engaging protrusion 15 is provided on an end edge part on the outer surface side of the upper end of the pipe block body 10 and tapered parts are provided on both side surfaces. Therefore, a combustion product rises along the inclination of the outer surface 14 of the pipe block body 10. Thus, it is difficult to form a flow entering the inner surface side of the pipe block body 10 from the joint parts 10a of upper and lower adjacent pipe block bodies 10, 10... so that the space of the joint parts 20a can be widened, Further, a space between the right and left adjacent joints can be increased and the outer surface side of the space can be decreased.
KIMURA KOICHI
GOTO YOSHIHIKO
ITO YASUO
OKABE TOSHIHISA
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