Turbine engine tie rod systems

A gas turbine engine turbine section comprising:

• an inner diameter structure;
• a turbine exhaust case surrounding the inner diameter structure and having an outer ring and an inner ring in concentric and radially spaced relationship and a plurality of circumferentially spaced hollow struts interconnecting and supporting said inner ring and said outer ring to each other;
• an outer casing surrounding said outer ring;
• and
• a plurality of tie rod assemblies interconnecting said inner diameter structure and said outer casing, each of said tie rod assemblies comprising:
• a tie rod having:
• an inner diameter end;
• an outer diameter end;
• an eyelet of an inner diameter spherical bearing formed at the inner diameter end;
• and
• an eyelet of an outer diameter spherical bearing formed at the outer diameter end;
• an inner diameter clevis mounted to the inner diameter structure and carrying a first spherical ball between arms of said second clevis, said first spherical ball captured by the inner diameter spherical bearing eyelet;
• an outer diameter clevis carrying a second spherical ball between arms of said outer diameter clevis, said second spherical ball captured by the outer diameter spherical bearing eyelet, a shank of said clevis extending to an outer diameter (OD) end of said clevis;
• and
• a tensioning bolt mated to a threaded opening formed in said clevis OD end whereby tightening said bolt applies a tension to said rod relative to the outer casing,
• wherein for each tie rod assembly:
• a radial span between a center of the outer diameter spherical bearing and an inner diameter surface of the outer casing is 30% to 200% of a radial span between the center of the inner diameter spherical bearing and the center of the outer diameter spherical bearing.

A gas turbine engine turbine section comprising:

• an inner diameter structure;
• a turbine exhaust case surrounding the inner diameter structure and having an outer ring and an inner ring in concentric and radially spaced relationship and a plurality of circumferentially spaced hollow struts interconnecting and supporting said inner ring and said outer ring to each other;
• an outer casing surrounding said outer ring;
• a plurality of tie rod assemblies interconnecting said inner diameter structure and said outer casing, each of said tie rod assemblies comprising:
• a tie rod having:
• an inner diameter end;
• an outer diameter end;
• and
• a spherical bearing eyelet formed at the outer diameter end;
• at least a first clevis carrying a spherical ball between arms of said clevis, said spherical ball captured by the spherical bearing eyelet, said first clevis comprising:
• a first shank having an outer diameter (OD) end;
• and
• a second shank having an outer diameter (OD) end;
• and
• a first bolt extending through an opening formed in said outer casing and mated to a threaded opening formed in said first shank OD end and a second bolt extending through an opening formed in said and mated to a threaded opening formed in said second shank OD end whereby tightening said first and second bolts applies a tension to said rod.