Once-through vapor generator

Claim 1

IN A BOILER HAVING A FORCED CIRCULATION FLUID CIRCULATION SYSTEM, A PLURALITY OF FLUID HEATING CIRCUITS ARRANGED FOR PARALLEL FLOW OF FLUID THERETHROUGH AND CONNECTED INTO SAID CIRCULATION SYSTEM AND INCLUDING SUBSTANTIALLY HORIZONTAL TUBE LENTHS, WALLS INCLUDING A TUBULAR LINING FORMING AN UPRIGHT CHAMBER, SAID TUBULAR LINING COMPRISING SECTION EXTENDING ONE ABOVE THE OTHER, EACH SECTION BEING FORMED BY PAIRS OF HORIZONTAL TUBE LENGTHS OF SAID CIRCUITS ARRANGED IN GROUPS TO PROVIDE SETS OF ADJACENT TUBE LENGTH ENDS DISTRIBUTED AROUND SAID CHAMBER, THE HORIZONTAL TUBE LENGTHS OF EACH PAIR EXTENDING IN OPPOSITE DIRECTIONS ALONG THE WALLS OF SAID CHAMBER, EACH SET OF TUBE LENGTH ENDS INCLUDING INLET ENDS AND OUTLET ENDS, AND MEANS FOR SUPPORTING SAID TUBE LENGTHS INCLUDING VERTICAL SUSPENSION MEANS, SAID LAST NAMED MEANS COMPRISING GROUPS OF VERTICALLY EXTENDING TRANSFER TUBES DISPOSED IN MOST PART EXTERIORLY OF AND DISTRIBUTED AROUND SAID CHAMBER, HORIZONTAL TUBE LENGTHS OF EACH SECTION BEING DIRECTLY CONNECTED BY A CORRESPONDING GROUP OF TRANSFER TUBES FOR SERIAL FLOW OF FLUID TO HORIZONTAL TUBE LENGTHS OF ANOTHER SECTION, EACH GROUP OF TRANSFER TUBES INCLUDING FIRST CONNECTOR TUBES LEADING AND DIRECTLY CONNECTED TO THE INLET ENDS OF ONE OF SAID SETS OF TUBE LENGTH ENDS TO PROVIDE CONTINUITY BETWEEN EACH FIRST CONNECTOR TUBE AND ITS CORRESPONDING TUBE LENGTH, AND SECOND CONNECTOR TUBES LEADING FROM AND DIRECTLY CONNECTED TO THE OUTLET ENDS OF SAID ONE SET OF TUBE LENGTH ENDS TO PROVIDEE CONTINUITY BETWEEN EACH SECOND CONNECTOR TUBE AND ITS CORRESPONDING TUBE LENGTH.