Helical coil steam generator

摘要

A steam generator includes a lower integrated tubesheet and plenum (ITP) configured to receive feedwater and a first set of heat transfer tubes fluidly coupled to a plurality of stubs protruding from a first side of the lower ITP. A second set of heat transfer tubes fluidly couples to plurality of stubs protruding from a second side of the lower ITP. The first set of heat transfer tubes is coiled in a substantially clock-wise direction, and the second set of heat transfer tubes is coiled in a substantially counter-clockwise direction. The steam generator further includes an upper ITP fluidly coupled to the first and second set of heat transfer tubes, wherein the feedwater entering the lower ITP is converted to steam in the first and second sets of heat transfer tubes. The upper ITP is configured to transport the steam away from the steam generator.

主权项

1. A method of manufacturing a steam generator, comprising:
removing a portion of a tube sheet to form a first plurality of stubs that protrude from the tube sheet; forming a first plurality of channels, wherein each of the first plurality of channels passes through the tube sheet and a corresponding stub of the first plurality of stubs; forming a first plurality of tubes into a first tube coil having a first diameter; connecting the first plurality of tubes to the first plurality of stubs, wherein an inner radius of each of the first plurality of tubes is approximately equal to an inner radius of each of the first plurality of stubs such that the first plurality of channels extend through the first plurality of stubs and into the first plurality of tubes; removing another portion of the tube sheet to form a second plurality of stubs that protrude from the tube sheet; forming a second plurality of channels, wherein each of the second plurality of channels passes through the tube sheet and a corresponding stub of the second plurality of stubs; forming a second plurality of tubes into a second tube coil having a second diameter, the second diameter being less than the first diameter; positioning the second tube coil inside the first tube coil; and connecting the second plurality of tubes to the second plurality of stubs.