Manufacture - Fabrication

FABRICATION

Fig. 22-6 Wide chord fan blade

construction

25. Major components of the gas turbine engine i.e. bearing housings, combustion and turbine casings, exhaust units, jet pipes, by-pass mixer units and low pressure compressor casings can be produced as fabricated assemblies using sheet materials such as stainless steel titanium and varying types of nickel alloys.

26. Other fabrication techniques for the manufacture of the low pressure compressor wide chord fan blade comprise rolled titanium side panels assembled in dies, hot twisted in a furnace and finally hot creep formed to achieve the necessary configu- ration. Chemical milling is used to recess the centre of each panel which sandwiches a honeycomb core, both panels and the honeycomb are finally joined together using automated furnaces where an activated diffusion bonding process takes place, ref. fig. 22-6.