Watertube boiler

Application Number: 00108253
Application Date: 2000.04.30
Publication Number: 1272606
Publication Date: 2000.11.08
Priority Information: 1999/4/30 JP 123577/99
International: F22B21/02
Applicant(s) Name: Miura Kogyo K. K.
Inventor(s) Name: Takubo Sho;Tanaka Takanori
Patent Agency Code: 72001
Patent Agent: yang yong
Abstract A plurality of first water tubes are arranged in a ring to form a first water tube train. A combustion chamber is provided inside the first water tube train, and a plurality of cooling water tubes are arranged annularly in an area where a gas exists in the combustion chamber during the combustion reaction to form a cooling water tube train. A clearance is arranged between adjacent cooling water tubes to allow passage of a gas during the combustion reaction, a combustion reaction continuation area is provided between the cooling water tube train and the first water tube train, and a plurality of second water tubes are arranged in a ring outside the first water tube train to form a second water tube train. A gas passage is provided between the first tube train and the second water tube train, so that a heat transfer area per unit space on the downstream side is made larger than that per unit space upstream side in the gas passage.