| 摘要 |
PROBLEM TO BE SOLVED: To improve a service life of a radiant tube by effectively preventing deformation of the tube.SOLUTION: This radiant tube 1 includes a straight pipe section 2 extending in the lateral direction. A first reinforcement rib 10A is disposed on a lower position on an outer periphery of at least a straight pipe part 2a as a part of the straight pipe section 2, and the first reinforcement rib 10A has a coefficient of thermal expansion smaller than that of a material of the radiant tube 1. |
