Turbine for the expansion of gas/vapour provided with contrast means of the axial thrust on the drive shaft

A turbine for the expansion of gas and vapor, comprising:

• a body or case;
• a fixed external sleeve member, overhanging frontally from a frontal wall of said case;
• and
• a turbine shaft extending coaxially and rotating in said external sleeve member with the interposition of a supporting unit, said external sleeve member having a head flange to axially hold said supporting unit and said shaft ending with a joint to connect said shaft to a device to be operated, wherein said supporting unit includes ball bearings to support the turbine shaft in said external sleeve member, and between said external sleeve member and a contiguous end of said turbine shaft an assembly is provided to generate an adjustable axial force so as to compensate the axial thrust of the turbine shaft to limit the application of improper axial loads on the ball bearings, said assembly comprising a fixed element attached to the external sleeve member and a moving element located concentrically around the turbine shaft, and said moving element being associated with the joint of the turbine shaft with the interposition of a bearing, and said fixed element and said moving element being coupled to delimit between said fixed element and said moving element a chamber fed by a fluid under pressure to generate a contrasting axial force opposed to the axial thrust on said shaft, said force being adjustable according to a variation in the fluid pressure fed into the chamber between the fixed element and moving element in response to at least the pressure of the fluid in the turbine, wherein between said fixed element and said moving element springs are placed operating in opposition to the thrust of the fluid in said chamber.

A turbine for the expansion of gas and vapor, comprising:

• a body or case;
• a fixed external sleeve member, overhanging frontally from a frontal wall of said case;
• and
• a turbine shaft extending coaxially and rotating in said external sleeve member with the interposition of a supporting unit, said external sleeve member having a head flange to axially hold said supporting unit and said shaft ending with a joint to connect said shaft to a device to be operated, wherein said supporting unit includes ball bearings to support the turbine shaft in said external sleeve member, and between said external sleeve member and a contiguous end of said turbine shaft an aggregate assembly is provided to generate an adjustable axial force so as to compensate the axial thrust of the turbine shaft to limit the application of improper axial loads on the ball bearings, wherein said assembly comprises a fixed element attached to the external sleeve member and a moving element located concentrically around the turbine shaft, said moving element being connected to the joint integral with the turbine shaft, and said fixed element being attached to an electromagnet facing the moving element, so as to generate the axial movements of the moving element and to reciprocally stress the turbine shaft with an adjustable axial force by means of a variation of the current fed to the electromagnet and in response at least to the pressure of the fluid flowing through the turbine.