| 摘要 |
PURPOSE:To obtain steam of a higher temperature by further heating hot water or steam obtained by heating a spiral water tube by means of a tubular heating body in a combustion chamber. CONSTITUTION:Hot water or steam moves to the side of a small diameter portion through a forcible circulating operation of a spiral water tube 8, and is introduced into a small-diameter annular water tube 11a of a tubular heating body 9. Hot water or steam is further heated because the tubular heating body 9 is heated by combustion flame of a burner 7. Thus, such a circulating operation is obtained in which hot water or steam is introduced into a large diameter annulary water tube 11b from the small-diameter annular water tube 11a via a connecting tube 12a and returns back to the small-diameter annular tube 11a via another connecting tube 12a. On the other hand, a circulating operation is obtained in which a part of other hot water or stream within a connecting tube 12b is forcibly circulated in such a manner that it is introduced into a remote part of the connecting tube 12b through a small-diameter annular water tube 11a and further returns back again to the small-diameter annular water tube 11a. Still further, a circulating operation for forcibly circulating hot water or steam within a connecting tube 12c in such a manner that it is introduced into the remote part of the connecting tube 12c from the small-diameter annular connecting tube 11a via the connecting tube 12a further from the large-diameter annular water tube 11b, and returns back again to the large-diameter annular water tube 11b. |
