| 摘要 |
A furnace wall tube (35) provided in a boiler and the interior of which is at supercritical pressure, and through which a heat medium circulates, said furnace wall tube having: spiral groove parts (36) formed in the inner peripheral surface and running in the axial direction of the tube; and rib parts (37) formed by means of the spiral grooves (36) so as to protrude radially inward. In a cross section along the axial direction of the tube, when the width [mm] of the groove parts (36) in tube axial direction is Wg, the height [mm] of the rib parts (37) in the radial direction is Hr, and the outer diameter [mm] of the tube is D, then the width (Wg) [mm] of the groove parts (36), the height (Hr) [mm] of the rib parts (37), and the tube diameter (D) [mm] satisfy the relationship Wg/(Hrˆ™D) > 0.40. |
