Set of turbines and a turbine train comprising at least one such set

A set of turbines, comprising:

• a first turbine comprising:
• a first case, a first shaft supported in the first case, first support elements radially interposed between the first shaft and the first case and configured to enable free rotation of the first shaft with respect to the first case about a first main axis, and a first rotor provided with first rotor blades and joined to a distal end of the first shaft, wherein the first rotor is supported in an overhung manner with respect to the first support elements, wherein the first rotor has a first front face facing the opposite side with respect to the first support elements;
• a second turbine comprising:
• a second case, a second shaft supported in the second case, second support elements radially interposed between the second shaft and the second case and configured to enable free rotation of the second shaft with respect to the second case about a second main axis, and a second rotor provided with second rotor blades and joined to a distal end of the second shaft, wherein the second rotor is supported in an overhung manner with respect to the second support elements, wherein the second rotor has a second front face facing the opposite side with respect to the second support elements;
• and
• a casing connected to the first case and to the second case;
• wherein the first front face faces the second front face and the first main axis is substantially aligned with the second main axis;
• wherein the set of turbines further comprises a connection element connected to the first front face and to the second front face to transmit rotation from the first shaft to the second shaft or vice versa;
• wherein the connection element comprises at least one elastic joint configured to minimize the rotordynamic influence of the first turbine and the second turbine on each other,
• wherein the connection element is contained in the casing,
• wherein the casing comprises a radially internal tubular body and a radially external tubular body that extend between the first case and the second case, and are substantially coaxial with the connection element, and
• wherein the casing delimits at least one conduit for a working fluid, and the at least one conduit is delimited between the radially internal tubular body and the radially external tubular body.