Expansion joint for gas turbines

An expansion joint for use between a turbine duct and an exhaust duct, comprising:

• a flange attached to the turbine duct;
• and
• a plurality of plates attached to the exhaust duct and extending towards the flange;
• the plurality of plates and the flange comprising a gap therebetween, the gap being narrower when the turbine duct is hot than when the turbine duct is cold;
• wherein the plurality of plates comprises a plurality of apertures therein;
• and
• wherein the plurality of plates is attached to the exhaust duct via bolts positioned within the plurality of apertures and wherein the plurality of apertures each comprises an oversized diameter larger than the plurality of bolts so as to accommodate thermal growth of the plurality of plates.

A method of allowing fluids to drain from an exhaust duct when a turbine duct is cold while providing a smooth aerodynamic transition when the turbine duct is hot, comprising:

• positioning a plurality of plates on the exhaust duct so as to define a gap between the turbine duct and the plurality of plates;
• attaching a flexible element to the turbine duct about the gap and to the exhaust duct;
• heating the turbine duct;
• and
• expanding the turbine duct towards the plurality of plates so as to narrow the gap.