HOT-WATER BOILER Russian patent published in 2012 - IPC F24H1/00 

FIELD: power industry.

SUBSTANCE: boiler includes cylindrical furnace, burner installed on the furnace end surface, outlet hole, supply and discharge pipelines and heating surfaces connected to supply and discharge pipelines and consisting of waterwall part formed with a bank of bare spiral tubes and two (external and internal) stages of convection part, which are concentrically located about internal one with a gap. Each of the stages of convection part is formed with bank of spiral tubes. Tube bank of waterwall part is gas-tight or is equipped with external gas-tight leading cylinder. Stages of convection part are adjacent to furnace end surface which is opposite to the burner and are equipped with spiral guide straps arranged on outer side of each tube bank of convection part. Tube bank of internal stage of convection part is wound along the radius equal to radius of winding of tube bank of waterwall part, and is connected by means of one end to the latter, and by means of the other end - to tube bank of its external stage. Tubes of both stages of convection part are provided with finning. Outlet hole is located on the side of external stage of convection part.

EFFECT: reduction of local hydraulic resistances.

4 cl, 3 dwg