| abstract |
Methods of making gas turbine structures with cooling channels, such as, for example, combustor/transition pieces for gas turbines having a double wall with a plurality of cooling channels, having axially and/or circumferential cross-flow passages positioned between the structure's inner member and the outer member to provide cooling air thereto, are disclosed. A representative method of producing such annular structures having a hot and a cold wall, and joining ribs, for the inner and the outer components of an annulus, such as for jet engine turbine combustors, to net shape as an annular pre-form includes: forming a pre-form assembly including materials for the hot wall, cold wall, and ribs and sacrificial segments for maintaining cooling channels during forming of the pre-assembly and later processing; rolling the pre-form to a required thickness and length as a flat pre-form; hoop-rolling the preform to a required thickness and a required length; welding the assembly; ring rolling to the pre-form to a desired inner diameter; ring-rolling or metal spinning the pre-form to produce the proper wall contour and removing the sacrificial material to open the cooling channels. |