Turbomachine and corresponding method for dismantling thereof

Abstract

A turbomachine comprises: a case (2) defining a transit circuit (3a, 4a, 5a) for a process fluid (F); a rotor assembly (7) having a shaft (9) that develops through the case (2) with opposite ends (9a, 9b) accessible from the outside and an impeller (10) interposed between the ends (9a, 9b) of the shaft, rotatable, integral with the shaft (9), by action of the process fluid (F) that circulates in the transit circuit (3a, 4a, 5a); a stator assembly (8) that comprises a sleeve (13, 17) for each end (9a, 9b) of the shaft (9) and a respective sealing insulating element (14) interposed between each sleeve (13, 16) and the respective end (9a, 9b) of the shaft (9) in such a way as to isolate the transit circuit (3a, 4a, 5a) of the process fluid (F) with respect to the outside; un support bearing (19, 20) operatively interposed between each end (9a, 9b) of the shaft (9) and the respective sleeve (13, 16), outside with respect to the corresponding sealing insulating element (14, 17); wherein each sleeve (13, 16) is longitudinally movable with respect to the shaft (9) for intercepting a respective circumferential relief (11, 12) radially projecting from the shaft (9) between the turbine (10) and the respective sealing insulating element (14, 17) and determining a further sealing insulating barrier (21, 22) between the transit circuit (3a, 4a, 5a) and the respective insulating element (14, 17), allowing the disengagement of the respective support bearing (19, 20) and / or of the respective sealing insulating element (14, 17) from the shaft (9) without leakage of the process fluid (F) along the respective end (9a, 9b) of the shaft (9).

Description

[0001] TURBOMACHINE AND CORRESPONDING METHOD FOR DISMANTLING THEREOF

[0002] DESCRIPTION

[0003] Field of the finding

[0004] The present invention has as its object a turbomachine.

[0005] For the purposes of the present invention, by turbomachine is intended a rotary machine that exchanges the energy of a continuous process fluid, moving within an opportune circuit, with a rotor rotating in a stator. The rotor is generally constituted by a shaft on which one or more impellers peripherally equipped with blades are keyed. In driving turbomachines, the blades are rotated by the process fluid, so that the wheels and shaft are also rotated by this fluid. In working turbomachines, the rotor transfers energy to the process fluid. The stator is usually composed of a case that defines at least partially the circuit of the process fluid and may provide for a series of blades or straighteners of the flow of the process fluid that flows between the rotor blades.

[0006] The present invention specifically refers to the isolation of some components of the rotor and of the stator of the turbomachine with respect to the transit circuit of the process fluid. In particular, the present invention focuses on respective sealing barriers that are defined between the impeller of the turbomachine and the ends of the rotor in order to allow the maintenance of some components of the turbomachine without leakage of process fluid.

[0007] Background of the finding

[0008] The public document FR3106850A1 shows a turbomachine provided with a stator and a rotor, in particular a shaft, which rotates about a corresponding rotation axis. The stator is defined by a series of components, at least one of which has a compartment in which circulates a working fluid that may be toxic and / or dangerous. The rotor shaft develops through the stator components, consequently also crossing the compartment for the circulation of the working fluid. The rotor shaft is rotatably supported by corresponding assemblies comprising bearings and sealing insulating elements located at the ends of the shaft. Between the stator component defining the compartment for the circulation of the working fluid and the stator component provided with the bearing / sealing insulating element assembly, are operatively arranged: an additional sealing insulating element sleeved on the rotor shaft which can be controlled in movement along the latter to create an additional sealing between the compartment for the circulation of the working fluid and the bearing; and an actuating mechanism of the movement of the insulating element provided with at least one power transmission by means of opportunely geared toothed wheels.

[0009] In detail, the additional sealing insulating element has a sealing face at least partially counter-shaped to a portion of the rotor shaft and provided with corresponding 0- ring seals, so that when moved towards the working fluid circulation compartment, it abuts against the rotor shaft, isolating the corresponding bearing from the working fluid.

[0010] The public document US2022381349A1 shows too an axial turbomachine that has a stator and a rotor, in the form of a shaft, which rotates about a corresponding rotation axis. The stator has a concavity, at which is housed, operatively, a sealing ring, which is opportunely keyed on the rotor shaft. Between the rotor shaft and the stator, at the concavity of the latter, there is a cavity or gap through which a working fluid or gas can circulate. The gap delineates a communication channel between at least two compartments, one inner and one outer, defined between the stator and the rotor shaft. The gap is also in fluid communication with a duct for supplying the working fluid or gas which develops at least through the stator according to a position intermediate between the inner compartment and the outer compartment.

[0011] A labyrinth sealing is also arranged between the stator and the rotor shaft in proximity of the inner compartment and at an end of the gap.

[0012] A lip annular seal, having a “V” profile, is arranged inside an annular niche obtained in the sealing ring, at the gap, so that the lip annular seal is interposed between the stator and the sealing ring of the rotor shaft. The profile of the lip annular seal is such as to allow its squeezing under the action of the centrifugal force that prevails when the rotor shaft rotates together with the sealing ring.

[0013] A further annular mechanical sealing is provided in the gap in proximity of or at the outer compartment. The annular mechanical sealing comprises a first sealing annular body which is arranged adjacent to the sealing ring in such a way as to firmly rotate with the latter and a sliding sealing ring which is connected to the stator resulting still during the rotation of the rotor shaft. In an operating condition, i.e. with the rotating rotor shaft, the lip annular seal is compressed due to the centrifugal force putting in fluid communication the entire gap with the inner compartment. In this situation, the sealing towards the outer compartment is guaranteed by the mechanical sealing. A supply of working fluid or gas through the corresponding supply duct determines a flow of working fluid into the gap and towards the inner compartment sufficient to withstand the leakage of working fluid or gas from that inner compartment. During the operation, the working fluid present in the inner compartment and at the labyrinth sealing is induced to move at high speed creating a buffer effect.

[0014] In a stopping condition of the rotor shaft and of the corresponding sealing ring, the working fluid or gas, present in the inner compartment, tends to flow beyond the labyrinth sealing inside the gap and towards the lip annular seal, which determines its blocking with respect to the mechanical sealing and the outer compartment. In this situation, the supply of working fluid or gas through the supply duct may be reduced in intensity or, even interrupted, since the sealing is ensured by the lip annular sealing.

[0015] The public document EP3743601A1 shows a turbomachine provided with a stator and a rotor, in particular a shaft provided with at least one cantilevered disc, which rotates about a corresponding rotation axis. Between the stator and the rotor shaft is defined a first compartment in which the rolling support bearings of the shaft itself are located. In addition, between the stator and the disc is defined a second compartment which is occupied by a respective working fluid.

[0016] At least one annular static sealing is interposed between the rotor shaft and the stator according to a position intermediate between the first compartment and the second compartment to isolate one from the other and prevent leakages of working fluid from the second compartment to the first one.

[0017] The radial turbomachine comprises also a movable annular sealing operating inside the second compartment. The movable annular sealing has a disc-shaped or annular portion provided with at least one O-ring seal facing the inside of the rotor shaft disc. The movable annular sealing is controlled by a fluid dynamic and / or mechanical device to abut against the inner surface of the disc and determine a sealing barrier that isolates the entire rotor shaft, including the static annular sealing, from the second compartment. The actuation of the movable annular sealing is performed when the turbomachine is in a stopping condition, with the rotor shaft and the respective disc at a standstill. Once the static annular sealing has been actuated to isolate the entire rotor shaft with respect to the second compartment, it is possible to perform the maintenance or the replacement of the rolling support bearings and / or of the static annular sealing.

[0018] EP2422049B1 discloses a turbine with a body with an inlet and an outlet for a fluid and a turbine shaft. The turbine includes a stator and a rotor, which are associated with each other and with the turbine shaft, and a support system designed to support the turbine shaft inside the body. The support system has a supporting unit and a tubular element coaxial with the shaft. The supporting unit is movable with respect to the tubular element such that it can be inserted in the tubular element when the turbine is operating or removed to carry out maintenance operations.

[0019] Summary

[0020] Generally, in the field of turbomachines, it is known to provide different areas in which to provide for an isolation of the circuit dedicated to the working or process fluid with respect to certain components of the machine. If in fact it is considered, for example, the previously described state of the art solutions, it is possible to note that are provided, in addition to permanent static sealings, movable sealings which are activated to isolate specific components of the latter when the machine is stopped.

[0021] Although these forms of sealing isolation for specific areas or zones of turbomachines are known and fulfill the task of confining within predetermined space limits the circuit dedicated to the permanence and transit of working or process fluids, the Applicant has observed that the systems and solutions in the state of the art are particularly complex, difficult to maintain, and expensive.

[0022] The complexity of the known systems and solutions depends significantly on the different and complicated mechanisms that must actuate the movement of the movable sealing within the structure of the respective turbomachines. In fact, in some cases, gear-driven mechanical movement systems are provided, in others, fluid dynamic systems that require the arrangement of dedicated fluid dynamic circuits, and in yet others, complicated systems for channeling the working or process fluid between the rotor and the stator. Obviously, the more complex the systems and solutions are, the more difficult and complicated the ordinary and extraordinary maintenance operations of these systems become.

[0023] It should also be considered that the complexity of the systems and solutions described above has a considerable impact on the overall costs of the machines and their maintenance costs. Indirect costs generated by long machine downtime and production shutdowns, necessary for carrying out the usual maintenance operations, must also be taken into account.

[0024] The Applicant has therefore perceived the need to simplify the structure of the turbomachine in order to simplify the sealing isolation of the components thereof which are normally subject to periodic maintenance interventions, in order to overcome the drawbacks present in the known art solutions.

[0025] In addition to the objective of conceptual and structural simplification of the sealing isolations provided in these turbomachines, the Applicant has also set the objective of facilitating ordinary and extraordinary maintenance interventions on some components of the machine, as well as reducing the time and costs associated thereto.

[0026] The Applicant has found that the above indicated objectives and others can be satisfactorily achieved according to the following aspects and / or claims.

[0027] More specifically, according to a 1stindependent aspect of the present invention, is provided a turbomachine that comprises:

[0028] - a case (2) that defines an inlet chamber (3a) of a process fluid (F), a discharge chamber (5a) of the process fluid (F) and a transit channel (4a) that develops between the inlet chamber (3a) and the discharge chamber (5a) in fluid communication with such chambers (3a, 5a);

[0029] - at least one rotor assembly (7) that comprises: a shaft (9) that develops at least partially through the case (2) and has a first end (9a) arranged substantially at the inlet chamber (3a) and a second end (9b), opposite the first end (9a), arranged substantially at the discharge chamber (5a), wherein the shaft (9) is free to rotate about an its own longitudinal development axis (X); at least one impeller (10) provided with a plurality of blades engaged to the shaft (9) at the transit channel (4a) of the case (2), between the first end (9a) and the second end (9b) of such shaft (9), wherein the blades of the impeller (10) are rotatable, integral with the shaft (9) and about the longitudinal development axis (X) of the latter, by action of the process fluid (F) in transit from the inlet chamber (3a) to the discharge chamber (5a) through the transit channel (4a);

[0030] - at least one stator assembly (8) that comprises: a first sleeve (13) arranged between the inlet chamber (3a) of the case (2) and the first end (9a) of the shaft (9); a first sealing insulating element (14), in particular a cartridge mechanical sealing, operatively interposed between the first sleeve (13) and the first end (9a) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the inlet chamber (3a) with respect to the outside at the first end (9a) of the shaft (9); a second sleeve (16) arranged between the discharge chamber (5a) of the case (2) and the second end (9b) of the shaft (9); a second sealing insulating element (17), in particular a cartridge mechanical sealing, operatively interposed between the second sleeve (16) and the second end (9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the discharge chamber (5a) with respect to the outside at the second end (9b) of the shaft (9);

[0031] - at least one support bearing (19, 20) operatively interposed between each end (9a, 9b) of the shaft (9) and the respective sleeve (13, 16), outside with respect to the corresponding sealing insulating element (14, 17); wherein at least one of said first and second sleeve (13, 16) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the respective chamber (3a, 5a) is determined by the respective sealing element (14, 17) and a second position, wherein such sleeve (13, 16) intercepts a respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the respective sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective insulating element (14, 17) and allowing the disengagement of the respective support bearing (19, 20) and / or of the respective sealing insulating element (14, 17) from the shaft (9) without leakage of the process fluid (F) along the respective end (9a, 9b) of the shaft (9).

[0032] In a further 1stbis independent aspect, which may be combined with the preceding aspect and / or with any one of the following aspects, is provided a turbomachine that comprises: - a case (2) that defines an inlet chamber (3a) of a process fluid (F), a discharge chamber (5a) of the process fluid (F) and a transit channel (4a) that develops between the inlet chamber (3a) and the discharge chamber (5a) in fluid communication with such chambers (3a, 5a);

[0033] - at least one rotor assembly (7) that comprises: a shaft (9) that develops at least partially through the case (2) and has a first end (9a) arranged substantially at the inlet chamber (3a) and a second end (9b), opposite the first end (9a), arranged substantially at the discharge chamber (5a), wherein the shaft (9) is free to rotate about an its own longitudinal development axis (X); at least one impeller (10) provided with a plurality of blades engaged to the shaft (9) at the transit channel (4a) of the case (2), between the first end (9a) and the second end (9b) of such shaft (9), wherein the blades of the impeller (10) are rotatable, integral with the shaft (9) and about the longitudinal development axis (X) of the latter, by action of the process fluid (F) in transit from the inlet chamber (3a) to the discharge chamber (5a) through the transit channel (4a);

[0034] - at least one stator assembly (8) that comprises: a first sleeve (13) arranged between the inlet chamber (3a) of the case (2) and the first end (9a) of the shaft (9); a first sealing insulating element (14), in particular a cartridge mechanical sealing, operatively interposed between the first sleeve (13) and the first end (9a) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the inlet chamber (3a) with respect to the outside at the first end (9a) of the shaft (9); a second sleeve (16) arranged between the discharge chamber (5a) of the case (2) and the second end (9b) of the shaft (9); a second sealing insulating element (17), in particular a cartridge mechanical sealing, operatively interposed between the second sleeve (16) and the second end (9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the discharge chamber (5a) with respect to the outside at the second end (9b) of the shaft (9);

[0035] - at least one support bearing (19, 20) operatively interposed between each end (9a, 9b) of the shaft (9) and the respective sleeve (13, 16), outside with respect to the corresponding sealing insulating element (14, 17); wherein: at least the first sleeve (13) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position, wherein the isolation of the transit channel (4a) and / or of the inlet chamber (3a) of the case (2) with respect to the outside is determined by the first sealing insulating element (14) and a second position, wherein the first sleeve (13) intercepts a respective first circumferential relief (11 ) projecting transversally from the shaft (9) between the impeller (10) and the respective first sealing insulating element (14) determining a further first sealing insulating barrier (21 ) between the transit channel (4a) and / or the respective inlet chamber (3a) of the case (2) and the respective first insulating element (14), and allowing the disengagement of the respective support bearing (19) and / or of the respective first sealing insulating element (14) from the first end (9a) from the shaft (9) without leakage of the process fluid (F) along the respective first end (9a) of the shaft (9);

[0036] - the second sleeve (16) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position, wherein the isolation of the transit channel (4a) and / or of the discharge chamber (5a) of the case (2) with respect to the outside is determined by the second sealing insulating element (17) and a second position, wherein the second sleeve (16) intercepts a respective second circumferential relief (12) projecting transversally from the shaft (9) between the impeller (10) and the respective second sealing insulating element (17) determining a further second sealing insulating barrier (22) between the transit channel (4a) and / or the respective outlet chamber (5a) of the case (2) and the respective second insulating element (17) and allowing the disengagement of the respective support bearing (20) and / or of the respective second sealing insulating element (17) from the second end (9b) from the shaft (9) without leakage of the process fluid (F) along the respective second end (9b) of the shaft (9).

[0037] In a further 1stter independent aspect, which may be combined with any one of the preceding aspects and / or with any one of the following aspects, is provided a turbomachine (1 ) that comprises:

[0038] - a case (2) that defines an inlet chamber (3a) of a process fluid (F), a discharge chamber (5a) of the process fluid (F) and a transit channel (4a) that develops between the inlet chamber (3a) and the discharge chamber (5a) in fluid communication with such chambers (3a, 5a);

[0039] - at least one rotor assembly (7) that comprises: a shaft (9) that develops at least partially through the case (2) and has at least one end (9a, 9b) arranged substantially at one of the chambers (3a, 5a) of the case (2) wherein the shaft (9) is free to rotate about an its own longitudinal development axis (X); at least one impeller (10) provided with a plurality of blades engaged to the shaft (9) at the transit channel (4a) of the case (2) wherein the blades of the impeller (10) are rotatable, integral with the shaft (9) and about the longitudinal development axis (X) of the latter;

[0040] - at least one stator assembly (8) that comprises: a sleeve (13, 16) arranged between the at least one chamber (3a, 5a) of the case (2) and the end (9a, 9b) of the shaft (9); a sealing insulating element (14, 17) operatively interposed between the sleeve (13) and an end (9a, 9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the at least one chamber (3a, 5a) with respect to the outside at such end (9a, 9b) of the shaft (9);

[0041] - at least one support bearing (19, 20) operatively interposed between the end (9a, 9b) of the shaft (9) and the sleeve (13, 16), outside with respect to the sealing insulating element (14, 17); wherein the sleeve (13, 16) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the at least one chamber (3a, 5a) is determined by the sealing element (14, 17) and a second position, wherein such sleeve (13, 16) intercepts a respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the at least one chamber (3a, 5a) and the insulating element (14, 17) and allowing the disengagement of the support bearing (19, 20) and / or of the sealing insulating element (14, 17) from the shaft (9) without leakage of the process fluid (F) along the respective end (9a, 9b) of the shaft (9).

[0042] In a further 1stquater independent aspect, which can be combined with any one of the preceding aspects and / or with any one of the following aspects, a method is provided for dismantling a turbomachine of the type comprising:

[0043] - a case (2) that defines an inlet chamber (3a) of a process fluid (F), a discharge chamber (5a) of the process fluid (F) and a transit channel (4a) that develops between the inlet chamber (3a) and the discharge chamber (5a) in fluid communication with such chambers (3a, 5a); - at least one rotor assembly (7) that comprises: a shaft (9) that develops at least partially through the case (2) and has a first end (9a) arranged substantially at the inlet chamber (3a) and a second end (9b), opposite the first end (9a), arranged substantially at the discharge chamber (5a), wherein the shaft (9) is free to rotate about an its own longitudinal development axis (X); at least one impeller (10) provided with a plurality of blades engaged to the shaft (9) at the transit channel (4a) of the case (2), between the first end (9a) and the second end (9b) of such shaft (9), wherein the blades of the impeller (10) are rotatable, integral with the shaft (9) and about the longitudinal development axis (X) of the latter, by action of the process fluid (F) in transit from the inlet chamber (3a) to the discharge chamber (5a) through the transit channel (4a);

[0044] - at least one stator assembly (8) that comprises: a first sleeve (13) arranged between the inlet chamber (3a) of the case (2) and the first end (9a) of the shaft (9); a first sealing insulating element (14), in particular a cartridge mechanical sealing, operatively interposed between the first sleeve (13) and the first end (9a) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the inlet chamber (3a) with respect to the outside at the first end (9a) of the shaft (9); a second sleeve (16) arranged between the discharge chamber (5a) of the case (2) and the second end (9b) of the shaft (9); a second sealing insulating element (17), in particular a cartridge mechanical sealing, operatively interposed between the second sleeve (16) and the second end (9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the discharge chamber (5a) with respect to the outside at the second end (9b) of the shaft (9);

[0045] - at least one support bearing (19, 20) operatively interposed between each end (9a, 9b) of the shaft (9) and the respective sleeve (13, 16), outside with respect to the corresponding sealing insulating element (14, 17); wherein at least one of said first and second sleeve (13, 16) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the respective chamber (3a, 5a) is determined by the respective sealing element (14, 17) and a second position, wherein such sleeve (13, 16) intercepts a respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the respective sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective insulating element (14, 17) and allowing the disengagement of the respective support bearing (19, 20) and / or of the respective sealing insulating element (14, 17) from the shaft (9) without leakage of the process fluid (F) along the respective end (9a, 9b) of the shaft (9); the method for dismantling comprising the following steps:

[0046] (i) stopping the operation of the turbomachine (1 ) in such a way as to allow the access to one or more of its components;

[0047] (ii) removing a bearing (19, 20) from the respective end (9a, 9b) of the shaft (9) of the rotor assembly (7);

[0048] (iii) releasing the respective sealing insulating element (14, 17), at least with respect to the shaft (9);

[0049] (iv) releasing the respective sleeve (13, 16) with respect to the case (2) and to the shaft (9);

[0050] (v) moving the respective sleeve (13, 16) longitudinally along the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the respective chamber (3a, 5a) of the case (2) with respect to the outside is determined by the corresponding sealing insulating element (14, 17) and a second position, wherein the respective sleeve (13, 17) intercepts the respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the respective sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective insulating element (14, 17);

[0051] (vi) locking the respective sleeve in the second position to maintain the respective further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective first sealing insulating element (14, 17);

[0052] (vii) removing the respective sealing insulating element (14, 17) from the shaft (9).

[0053] In a 2ndaspect according to any one of the preceding aspects, the first sleeve (13) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position, wherein the isolation of the transit channel (4a) and / or of the inlet chamber (3a) of the case (2) with respect to the outside is determined by the first sealing insulating element (14) and a second position, wherein the first sleeve (13) intercepts a respective first circumferential relief (11 ) projecting transversally from the shaft (9) between the impeller (10) and the respective first sealing insulating element (14) determining a further first sealing insulating barrier (21 ) between the transit channel (4a) and / or the respective inlet chamber (3a) of the case (2) and the respective first insulating element (14), and allowing the disengagement of the respective support bearing (19) and / or of the respective first sealing insulating element (14) from the first end (9a) from the shaft (9) without leakage of the process fluid (F) along the respective first end (9a) of the shaft (9).

[0054] In a 3rdaspect according to any one of the preceding aspects, the first sleeve (13) is arranged internally to the case (2).

[0055] In a 4thaspect according to any one of the preceding aspects, the first sleeve (13) comprises a first end (13a) proximal to the first end (9a) of the shaft (9) and a second end (13c) distal to the first end (9a) of the shaft (9).

[0056] In a 5thaspect according to the preceding aspect, the first end (13a) of the first sleeve (13) has an annular edge (13b) projecting outwardly, transversally, optionally perpendicularly, to the longitudinal development axis (X) of the shaft (9).

[0057] In a 6thaspect according to the preceding aspect, at least one spacer (15) is arranged to remain between the annular edge (13b) of the first sleeve (13) and the case (2).

[0058] In a 7thaspect according to any one of the two preceding aspects, at least one spacer (15) is arranged to lock the first sleeve (13) to the case (2), the locking of the first sleeve (13) to the case (2) being determined by the interposition of the respective spacer (15) between the annular edge (13b) of the first end (13a) of the first sleeve (13) and the case (2), the removal of the spacer (15) from the first sleeve (13) allowing the movement of the first sleeve (13) with respect to the shaft (9), along a direction substantially parallel to the longitudinal development axis (X) of the latter. In an 8thaspect according to any one of the five preceding aspects, wherein the first sleeve (13) has an annular wall (13d) that develops transversally, preferably substantially perpendicularly, to the shaft (9) and substantially parallel to the respective circumferential relief (11 ) projecting from the shaft (9).

[0059] In a 9thaspect according to the preceding aspect, the annular wall (13d) of the second end (13c) of the first sleeve (13) develops transversally towards the shaft (9) according to an extent such that it has at least one striker portion (13e) that can abut on a corresponding striker surface (11 a) of the respective circumferential relief the first sealing insulating element (14), when the first sleeve (13) is in the second position.

[0060] In a 10thaspect according to any one of the two preceding aspects, at least one seal (23) is operatively interposed between the annular wall (13d) of the second end (13c) of the first sleeve (13) and the corresponding circumferential relief (11 ) of the shaft (9) to ensure a sealing at such circumferential relief (11 ) when the first sleeve (13) is arranged in the second position.

[0061] In a 11thaspect according to the preceding aspect when it depends on the 9thaspect, the seal (23) is operatively arranged between the striker portion (13e) of the annular wall (13d) of the second end (13c) of the first sleeve (13) and the corresponding circumferential relief (11 ) of the shaft (9).

[0062] In a 12thaspect according to the preceding aspect, the striker portion (13e) of the annular wall (13d) of the second end (13c) of the first sleeve (13) has at least one seat (25) for the housing of the respective seal (23).

[0063] In a 13thaspect according to the preceding aspect, the seal (23) occupies the respective seat (25) of the striker portion (13e) of the annular wall (13d) of the second end (13c) of the first sleeve (13) partially protruding therefrom in such a way as to remain compressed against the corresponding circumferential relief (11 ) of the shaft (9) when the first sleeve (13) is in the second position, the seal (23) ensuring the sealing at such circumferential relief (11 , 12) when the first sleeve (13) is in the second position.

[0064] In a 14thaspect according to any one of the four preceding aspects, the seal (23) has an annular shape.

[0065] In a 15thaspect according to any one of the five preceding aspects, the seal (23) is an O-Ring seal.

[0066] In a 16thaspect according to any one of the twelve preceding aspects, the first end (16a) of the second sleeve (16) has an annular edge (16b) projecting outwardly, transversally, optionally perpendicularly, to the longitudinal development axis (X) of the shaft (9).

[0067] In a 17thaspect according to the preceding aspect, at least one spacer (18) is arranged to remain between the annular edge (16b) of the second sleeve (16) and the case (2).

[0068] In a 18thaspect according to any one of the two preceding aspects, at least one spacer (18) is arranged to lock the second sleeve (16) to the case (2), the locking of the second sleeve (16) to the case (2) being determined by the interposition of the respective spacer (16) between the annular edge (16b) of the first end (16a) of the second sleeve (16) and the case (2), the removal of the spacer (18) from the second sleeve (16) allowing the movement of the second sleeve (16) with respect to the shaft (9), along a direction substantially parallel to the longitudinal development axis (X) of the latter.

[0069] In a 19thaspect according to any one of the five preceding aspects, wherein the second sleeve (16) has an annular wall (16d) that develops transversally, preferably substantially perpendicularly, to the shaft (9) and substantially parallel to the respective circumferential relief (12) projecting from the shaft (9).

[0070] In a 20thaspect according to the preceding aspect, the annular wall (16d) of the second end (16c) of the second sleeve (16) develops transversally towards the shaft (9) according to an extent such that it has at least one striker portion (16e) that can abut on a corresponding striker surface (12a) of the respective circumferential relief (12) of the shaft (9) directed opposite with respect to the impeller (10) and towards the second sealing insulating element (17), when the second sleeve (16) is in the second position.

[0071] In a 21staspect according to any one of the two preceding aspects, at least one seal (24) is operatively interposed between the annular wall (16d) of the second end (16c) of the second sleeve (16) and the corresponding circumferential relief (12) of the shaft (9) to ensure a sealing at such circumferential relief (12) when the second sleeve (16) is arranged in the second position.

[0072] In a 22ndaspect according to the preceding aspect when it depends on the 18thaspect, the seal (24) is operatively arranged between the striker portion (16e) of the annular wall (16d) of the second end (16c) of the second sleeve (16) and the corresponding circumferential relief (12) of the shaft (9).

[0073] In a 22ndbis aspect according to the preceding aspect, the striker portion (16e) of the annular wall (16d) of the second end (16c) of the second sleeve (16) has at least one seat (26) for the housing of the respective seal (24).

[0074] In a 23rdaspect according to the preceding aspect, the seal (24) occupies the respective seat (26) of the striker portion (16e) of the annular wall (16d) of the second end (16c) of the second sleeve (16) partially protruding therefrom in such a way as to remain compressed against the corresponding circumferential relief (12) of the shaft (9) when the second sleeve (16) is in the second position, the seal (24) ensuring the sealing at such circumferential relief (12) when the second sleeve (13) is in the second position.

[0075] In a 24thaspect according to any one of the four preceding aspects, the seal (24) has an annular shape.

[0076] In a 25thaspect according to any one of the five preceding aspects, the seal (24) is an O-Ring seal.

[0077] In a 26thaspect according to any one of the preceding aspects, the first sleeve (13) is housed at a first opening (6a) of a through axial housing (6) that develops through the case (2) from one side to the other thereof, the shaft (9) being operatively arranged in the through axial housing (6) and being coaxially arranged with respect to the first sleeve (13), at least one support bearing (19) being operatively interposed between the first end (9a) of the shaft (9) and an inner surface of the first sleeve (13).

[0078] In a 27thaspect according to the preceding aspect, the first sealing insulating element (14) is operatively sleeved on the first end (9a) of the shaft (9) in such a way as to result interposed between the first end (9a) of the shaft (9) and the inner surface of the first sleeve (13), the first sealing insulating element (14) being positioned between the respective relief (11 ) of the shaft (9) and the respective support bearing (19).

[0079] In a 28thaspect according to any one of the two preceding aspects, the second sleeve (16) is housed at a second opening (6a) of the through axial housing (6), opposite the first opening (6a), the shaft (9) being coaxially arranged with respect to the second sleeve (16), at least one support bearing (20) being operatively interposed between the second end (9b) of the shaft (9) and the inner surface of the second sleeve (16).

[0080] In a 29thaspect according to the preceding aspect, the second sealing insulating element (14) is operatively sleeved on the second end (9b) of the shaft (9) in such a way as to result interposed between the second end (9b) of the shaft (9) and the inner surface of the second sleeve (17), the second sealing insulating element (14) being positioned between the respective relief (12) of the shaft (9) and the respective support bearing (20).

[0081] In a 30thaspect according to any one of the preceding aspects, is provided a method for dismantling, optionally partially, of the turbomachine (1 ) that comprises the following steps: (i) stopping the operation of the turbomachine (1 ) in such a way as to allow the access to one or more of its components;

[0082] (ii) removing a bearing (19, 20) from the respective end (9a, 9b) of the shaft (9) of the rotor assembly (7);

[0083] (iii) releasing the respective sealing insulating element (14, 17), at least with respect to the shaft (9);

[0084] (iv) releasing the respective sleeve (13, 16) with respect to the case (2) and to the shaft (9);

[0085] (v) moving the respective sleeve (13, 16) longitudinally along the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the respective chamber (3a, 5a) of the case (2) with respect to the outside is determined by the corresponding sealing insulating element (14, 17) and a second position, wherein the respective sleeve (13, 17) intercepts the respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the respective sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective insulating element (14, 17);

[0086] (vi) locking the respective sleeve in the second position to maintain the respective further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective first sealing insulating element (14, 17);

[0087] (vii) removing the respective sealing insulating element (14, 17) from the shaft (9).

[0088] In a 31staspect according to the preceding aspect, the sequence of the steps for dismantling (i)-(vii) is performed for each of the ends (9a, 9b) of the shaft (9) of the rotor assembly (7) of the turbomachine (1 ), optionally on both the ends (9a, 9b) of the shaft (9).

[0089] In a 32ndaspect according to any one of the two preceding aspects, the unlocking of each sleeve (13, 16) with respect to the case (2) and to the shaft (9) is performed by means of the unlocking and the removal of the respective spacer interposed between the annular edge (13b, 16b) of the first end (13a, 16a) of the respective sleeve (13, 16) and the case (2).

[0090] In a 33rdaspect according to the preceding aspect, the unlocking of each sleeve (13, 16) with respect to the case (2) and to the shaft (9) is performed also by means of the removal of one or more fastening elements, such as fastening screws or similar fastening mechanisms, which operate between the respective sleeve (13, 17) and the case (2).

[0091] In a 34thaspect according to any one of the preceding aspects, the turbomachine is driving.

[0092] In a 35thaspect according to the preceding aspect, the turbomachine is an axial or radial turbine, optionally a centrifugal radial turbine (out-flow).

[0093] In a 36thaspect according to any one of the aspects 1 to 33, the turbomachine is operating.

[0094] Further characteristics and advantages will become clearer from the detailed description of preferred, but not exclusive, embodiments of turbomachines according to the present invention.

[0095] Description of figures

[0096] This description will be shown below with reference to the attached drawings, provided for indicative purposes only and, therefore, not limiting thereto, in which: figure 1 is a longitudinal section representation of a turbomachine, according to the present invention; figure 2 is an enlarged representation of a detail of figure 1 : figure 3 is a representation of a half-section of the turbomachine referred to in figure 1 , with a longitudinally displaced sleeve; figure 4 is an enlarged representation of a particular of figure 3; figure 5 is a representation of the same half-section of the turbomachine referred to in figure 3, with a further longitudinally displaced sleeve; figure 6 is an enlarged representation of a particular of figure 5; figure 7 is a representation of the same half-section of the turbomachine referred to in figure 5, from which some components were removed and highlighted the process fluid.

[0097] Definitions

[0098] In the present description and in the attached claims, the terms “axial,” “circumferential,” and “annular” are intended as referring to the rotation axis of the impeller.

[0099] In the present description and in the attached claims, with the term “through” referring to the “axial housing” is intended a space or channel that crosses entirely, from one side to the other, a respective body, in the specific case the “case” of the “turbomachine”.

[0100] Detailed description

[0101] With reference to the mentioned figures, with the reference number 1 it has been overall indicated a turbomachine, according to the present invention. In the nonlimiting example shown, the turbomachine 1 is an axial turbine.

[0102] As can be seen in the entire longitudinal section of Figure 1 , the turbomachine 1 comprises a case 2 that has three distinct blocks 3, 4, 5 opportunely connected between them. A first block 3 defines an inlet chamber 3a of a process fluid F which comes from a supply mouth 3b thereof. A second block 4 defines a transit channel 4a in fluid communication with the inlet chamber 3a, through which the process fluid F exits from the inlet chamber 3a. A third block 5 defines a discharge chamber 5a of the process fluid F in fluid communication with the transit channel 4a opposite with respect to the inlet chamber 3a, to allow the outflow of the process fluid F deriving from the transit channel 4a.

[0103] The case 2 of the turbomachine 1 has a through axial housing 6 that develops through the first 3, the secondo 4 and the third block 5. The inlet chamber 3a and the discharge chamber 5a of the process fluid F develop about the through axial housing 6 defining respectively a first and a second opening 6a, 6b, respectively opposite.

[0104] As can be seen in figures 1 , 3, 5 and 7, the through axial housing 6 is designated to house a rotor assembly 7 and a stator assembly 8.

[0105] The rotor assembly 7 comprises a shaft 9 that develops through the through axial housing 6 of the case 2 with freedom of rotation about its longitudinal development axis X. The shaft 9 has a first end 9a arranged substantially at the first opening 6a of the through axial housing 6 and of the inlet chamber 3a of the case 2 and a second end 9b, opposite the first end 9a, arranged substantially at the second opening 6b of the through axial housing 6 and of the discharge chamber 5a.

[0106] The rotor assembly 7 comprises also at least one impeller 10 provided with a plurality of blades (not shown in figures as they are known) engaged to the shaft 9 at the transit channel 4a of the second block of the case 2, between the first and the second end 9a, 9b. In detail, the blades are arranged peripherally on the impeller to intercept the process fluid F that flows through the transit channel 4a from the inlet chamber 3a to the discharge chamber 5a. The flow of the process fluid F inside transit channel 4a causes the impeller and, consequently, the shaft 9 to rotate about its longitudinal development axis X which is in fact the rotation axis of the rotor assembly 7. In other words, blades of the impeller 10 are driven in rotation, solidly and jointly to the shaft 9 about the longitudinal development axis X of the latter, by action of the process fluid F in transit from the inlet chamber 3a to the discharge chamber 5a, through the transit channel 4a.

[0107] Between the impeller 10 and the first end 9a of the shaft 9 develops a first circumferential relief 11 that protrudes transversally from the shaft 9, preferably perpendicular to it. The first circumferential relief 11 can be made as one piece with the shaft 9 or fitted onto it, by means of known connection elements. Advantageously, the first circumferential relief 11 is localized at the innermost portion of the first opening 6a of the through axial housing 6.

[0108] Between the impeller 10 and the second end 9b of the shaft 9 develops a second circumferential relief 12 that protrudes transversally from the shaft 9, preferably perpendicularly thereto. Also the second circumferential relief 12 can be made as one piece with the shaft 9 or fitted onto it, by means of known connection elements. Advantageously, the second circumferential relief 12 is localized at the innermost portion of the second opening 6b of the through axial housing 6.

[0109] The stator assembly 8 comprises a first sleeve 13 arranged at the first opening 6a of the through axial housing 6 between the inlet chamber 3a of the first block 3 of the case 2 and the first end 9a of the shaft 9 and a first sealing insulating element 14, in particular a mechanical package seal, operatively interposed between the first sleeve 13 and the first end 9a of the shaft 9, in such a way as to isolate the transit channel 4a and / or the inlet chamber 3a with respect to the outside, at the first opening 6a of the through axial housing 6 and of the first end 9a of the shaft 9.

[0110] In detail, the first sleeve 13 has an outer shape that substantially recalls the inner profile of the first opening 6a of the through axial housing 6. Furthermore, the first sleeve 13 comprises a first end 13a, proximal to the first end 9a of the shaft 9, the first end 13a thereof has an annular edge 13b projecting transversally, preferably substantially perpendicularly, outwardly of the first sleeve 13 and a second end 13c, distal with respect to the first end 9a of the shaft 9, that has an annular wall 13d developing transversally, preferably substantially perpendicularly, towards the shaft 9, and substantially parallel to the first circumferential relief 11 . The first sleeve 13 is fixed to the first opening 6a of the through axial housing 6 by means of corresponding fastening elements, such as fastening screws or other similar connecting and locking elements.

[0111] In addition, between the annular edge 13b of the first end 13a of the first sleeve and the first block 3 that defines the inlet chamber 3a of the process fluid F is provided a first spacer 15 which contributes to the fixing of the first sleeve 13 realized by means of the aforementioned fastening elements.

[0112] The stator assembly 8 comprises also a second sleeve 16 arranged at the second opening 6b of the through axial housing 6 between the discharge chamber 5a of the third block 5 of the case 2 and the second end 9b of the shaft 9 and a second sealing insulating element 17, in particular a mechanical package seal, operatively interposed between the second sleeve 16 and the second end 9b of the shaft 9, in such a way as to isolate the transit channel 4a and / or the discharge chamber 5a with respect to the outside, at the second opening 6b of the through axial housing 6 and of the second end 9b of the shaft 9.

[0113] The second sleeve 16 has an outer shape that substantially recalls the inner profile of the second opening 6b of the through axial housing 6. Furthermore, the second sleeve 16 comprises a first end 16a, proximal to the second end 9b of the shaft 9, the first end 16a thereof has an annular edge 16b projecting transversally, preferably substantially perpendicularly, outwardly of the second sleeve 16 and a second end 16c, distal with respect to the second end 9b of the shaft 9, that has an annular wall 16d developing transversally, preferably substantially perpendicularly, towards the shaft 9, and substantially parallel to the second circumferential relief 12.

[0114] The second sleeve 16 is fixed to the second opening 6b of the through axial housing 6 by means of corresponding fastening elements, such as fastening screws or other similar connecting and locking elements.

[0115] In addition, between the annular edge 16b of the first end 16a of the second sleeve 16 and the third block 5 that defines the discharge chamber 5a of the process fluid F is provided a second spacer 18 which contributes to the fixing of the second sleeve 16 realized by means of the aforementioned fastening elements.

[0116] As can be seen in figures 1 and 3, the turbomachine 1 comprises also, for each end 9a, 9b of the shaft 9, at least one support bearing 19, 20, which is operatively interposed between the respective ends 9a, 9b of the shaft 9 and the corresponding sleeve 13, 16 according to an outer position with respect to the corresponding sealing insulating element 14, 17.

[0117] The support bearing 19 localized between the first end 9a of the shaft 9 and the first sleeve 13 is a bearing of radial type, whereas the support bearing 20 localized between the second end 9b of the shaft 9 and the second sleeve 16 is a bearing of radial-axial type, which supports the shaft 9 by means of a thrust-bearing collar 20a opportunely fitted onto the second end 9b thereof.

[0118] Advantageously, at least one of the sleeves 13, 16 of the stator assembly 8 is longitudinally movable with respect to the shaft 9 between a first position (figure 1 ) wherein the isolation of the transit channel 4a and / or of the respective chamber 3a, 5a of the case 2 is determined by the respective sealing insulating element 14, 17 and a second position (figures 5 and 7), wherein such sleeve 13, 16 intercepts a respective circumferential relief 11 , 12 that protrudes transversally from the shaft 9 between the impeller 10 and the respective sealing insulating element 14, 17 determining a further sealing insulating barrier 21 , 22 between the transit channel 4a and / or the respective chamber 3a, 5a of the case 2 and the respective insulating element 14, 17 and, allowing the disengagement of the respective support bearing 19, 20 and / or of the respective sealing insulating element 14, 17 from the shaft 9 without leakage of the process fluid F along the respective end 9a, 9b of the shaft 9.

[0119] In detail, the first sleeve 13 is longitudinally movable with respect to the shaft 9 between a first position (figures 1 and 2), wherein the isolation of the transit channel 4a and / or of the inlet chamber 3a of the case 2 with respect to the outside is determined by the first sealing insulating element 14 and a second position (figures 3, 4, 5 and 7), wherein the first sleeve 13 intercepts a respective first circumferential relief 11 projecting transversally from the shaft 9 between the impeller 10 and the respective first sealing insulating element 14 determining a further first sealing insulating barrier 21 between the transit channel 4a and / or the respective inlet chamber 3a of the case 2 and the respective first insulating element 13 and, allowing the disengagement of the respective support bearing 19 and / or of the respective first sealing insulating element 14 from the first end 9a of the shaft 9 without leakage of the process fluid F along such first end 9a and through the first opening 6a of the through axial housing 6. The second sleeve 16 is longitudinally movable with respect to the shaft 9 between a first position (figures 1 , 3 and 4), wherein the isolation of the transit channel 4a and / or of the discharge chamber 5a of the case 2 with respect to the outside is determined by the second sealing insulating element 17 and a second position (figures 5 to 7), wherein the second sleeve 16 intercepts a respective second circumferential relief 12 projecting transversally from the shaft 9 between the impeller 10 and the respective second sealing insulating element 17 determining a further second sealing insulating barrier 22 between the transit channel 4a and / or the respective outlet chamber 5a of the case 2 and the respective second insulating element 17 and, allowing the disengagement of the respective support bearing 20 and / or of the respective second sealing insulating element 17 from the second end 9b of the shaft 9 without leakage of the process fluid F along such end and through the second opening 6b of the through axial housing 6.

[0120] As can be seen in the attached figures, the annular wall 13d, 16d of each sleeve 13, 16 develops from the respective second end 13c of this latter towards the shaft 9 according to an extent such that it has at least one respective striker portion 13e, 16e that can abut on a corresponding surface 11 a, 12a (figures 2, 4 and 6) of the respective circumferential relief 11 , 12 of the shaft 9, directed towards the corresponding sealing insulating element 14, 17 when the respective sleeve 13, 16 is in the second position.

[0121] In order to ensure an optimal sealing between the striker portion 13e, 16e of the annular wall 13d, 16d of the second end 13c, 16c of the respective sleeve 13, 16 and the corresponding circumferential relief 11 , 12 when the respective sleeve 13, 16 is in the second position, is provided at least one respective seal 23, 24, optionally of annular shape, in particular an O-Ring seal. In detail, each seal 23, 24 is operatively interposed between the annular striker wall 13d, 16d of the second end 13c, 16c of the respective sleeve 13, 16 and the corresponding circumferential relief 11 , 12 of the shaft 9 to ensure a sealing at such circumferential relief 11 , 12 when the respective sleeve 13, 16 is arranged in the second position.

[0122] Advantageously, the striker portion 13e, 16e of the annular wall 13d, 16d of the second end 13c, 16c of each sleeve 13, 16 has at least one seat 25, 26 (figures 2, 4 and 6) for the housing of the respective seal 23, 24, which occupies partially the respective seat 25, 26 protruding therefrom towards the respective circumferential relief 11 , 12 of the shaft 9, when the sleeve 13, 16 is in the first position. When the sleeve 13, 16 is in the second position, the respective seal 23, 24, is compressed between the respective annular wall 13d, 16d and the corresponding circumferential relief 11 , 12 of the shaft 9 ensuring the sealing at such circumferential relief 11 , 12 and defining the respective sealing barrier 21 , 22 between the respective sealing insulating element 14, 17 and the transit channel 4a of the case 2.

[0123] The turbomachine 1 above described and shown in figures refers to a turbomachine the shaft 9 thereof has two ends 9a, 9b facing, on opposite sides, outwardly and corresponding circumferential reliefs 11 , 12. Consequently, the described and shown turbomachine has for each end 9a, 9b of the shaft 9 a respective sleeve 13, 16, a respective support bearing 19, 20, a corresponding spacer 15, 18 and a respective sealing insulating element 14, 17, where each sleeve 13, 16 can be moved between the first and the second position to create a further sealing barrier and allow the removal in safety and without leakage of process fluid of the respective sealing insulating element 14, 17. The concept of movement of the sleeve 13, 17 along the shaft 9 until the interception of a respective circumferential relief 11 , 12 of the latter to create a respective sealing barrier 21 , 22 and isolate the respective sealing insulating element 14, 17 can also be applied to a turbomachine with cantilevered tree, i.e., with only one end provided with components that must be removed from the shaft for periodic maintenance or replacement. In this case, it is provided a single sleeve movable between the first and the second position in which, intercepting the respective circumferential relief of the shaft, moves the point of the sealing barrier, allowing the removal of the respective sealing insulating element that must be controlled and / or maintained.

[0124] Furthermore, although the shown turbomachine 1 is an axial turbine, the invention equally applies to radial turbines, for example to centrifugal radial turbines (out-flow), or to operating turbomachines.

[0125] The invention provides for a method for dismantling, at least partial, of the abovedescribed turbomachine 1 in order to allow the maintenance interventions on one or more components thereof, as well as the possible replacement of such components. The dismantling method provides, first of all, for the stopping of the turbomachine 1 , in such a way that the components thereof are accessible in complete safety. Once the turbomachine 1 is stopped, it is possible to intervene on the components thereof that are at the first end 9a of the shaft 9, or on the components that are at the second end 9b of such shaft 9, or on the components arranged at both ends 9a, 9b of the shaft 9.

[0126] Once the components that need to be maintained or replaced have been identified, the dismantling method of the turbomachine 1 provides firstly for a step of removal of the support bearing 19, 20 from the respective end 9a, 9b of the shaft 9. This step involves the unlocking of the corresponding support bearing 19, 20 and its subsequent removal from the respective end 9a, 9b of the shaft 9 until its complete disengagement.

[0127] With particular reference to second end 9b of the shaft 9 and to the second opening 6b of the through axial housing 6, previously or simultaneously to the removal of the corresponding support bearing 20 is unlocked and removed from the second end 9b of the shaft 9, the thrust-bearing collar 20a.

[0128] Subsequently to the removal of the respective support bearing 19, 20 from the shaft 9, is possible to subject such support bearing 19, 20 to one or more maintenance operations or provide for its disposal and replacement with a new identical support bearing 19, 20.

[0129] Once the support bearing 19, 20 is removed, is preferable releasing the corresponding sealing insulating element 14, 17 in such a way as to allow it to slide along the shaft 9. This step is performed by removing one or more locking screws or similar threaded locking elements provided therein.

[0130] Subsequently or before the unlocking of the respective sealing insulating element 14, 17, is performed also a step of removal of the corresponding spacer 15, 16 which blocks the corresponding sleeve 13, 16 against the respective block 3, 5 of the case 2. Once the spacer 15, 16 associated to the sleeve 13, 16 is removed, the method for dismantling involves a step of movement of the respective sleeve 13, 16 from the first position to the second position, in such a way that the annular wall 13d, 16d of the respective second end 13c, 16c abuts against the respective circumferential relief 11 , 12 of the shaft 9 compressing the corresponding seal 23, 24 and defining the corresponding further insulating barrier 21 , 22 which guarantees the sealing isolation between the transit channel 4a and the corresponding opening 6a, 6b of the through axial housing 6. Upon reaching the second position, the respective sleeve 13, 16 is blocked by means of opportune known fastening elements.

[0131] The step of movement of each sleeve 13, 16 from the first to the second position is performed in condition of engagement of the corresponding sealing insulating element 14, 17 between the shaft 9 and the corresponding sleeve 13, 16 in such a way that no undesired leakage of process fluid F occurs during the implementation of the dismantling method. Once the sleeve 13, 16 is blocked in the second position and the sealing insulating element 14, 17 is unblocked, it is possible to remove the latter, if necessary, by means of removing it from the corresponding end 9a, 9b of the shaft 9.

[0132] The removal of the corresponding sealing insulating element 14, 17 mainly depends on the need to perform one or more maintenance operations directly on the respective sealing insulating element 14, 17 or within the corresponding sleeve 13, 16. With regard to the removal of the respective sealing insulating element 14, 17, this operation is usually performed to directly maintain the latter or dispose of it or service it and replace it with a new sealing insulating element. On the other hand, with reference to maintenance interventions dedicated to each sleeve 13, 16, the removal of the respective sealing insulating element 14, 17 allows the easy access to the cavity of the sleeve 13, 16 for performing inspection and / or cleaning and / or lubrication operations or any other intervention that may be necessary.

[0133] List of elements

[0134] 1 Turbomachine

[0135] 2 Case

[0136] 3 First block

[0137] 3a Inlet chamber of the first block

[0138] 3b Supplying mouth of the inlet chamber of the first block

[0139] 4 Second block

[0140] 4a Transit channel of the second block

[0141] 5 Third block

[0142] 5a Discharge chamber of the third block

[0143] 6 Through axial housing

[0144] 6a First opening of the through axial housing

[0145] 6b Second opening of the through axial housing

[0146] 7 Rotor assembly

[0147] 8 Stator assembly

[0148] 9 Shaft

[0149] 9a First end of the shaft 9b Second end of the shaft

[0150] 10 Impeller

[0151] 11 First circumferential relief

[0152] 12 Second circumferential relief

[0153] 13 First sleeve

[0154] 13a First end of the first sleeve

[0155] 13b Annular edge of the first end of the first sleeve

[0156] 13c Second end of the first sleeve

[0157] 13d Annular wall of the second end of the first sleeve

[0158] 13e Striker portion of the annular wall of the second end of the first sleeve

[0159] 14 First sealing insulating element

[0160] 15 First spacer

[0161] 16 Second sleeve

[0162] 16a First end of the second sleeve

[0163] 16b Annular edge of the first end of the second sleeve

[0164] 16c Second end of the second sleeve

[0165] 16d Annular wall of the second end of the second sleeve

[0166] 16e Striker portion of the annular wall of the second end of the second sleeve

[0167] 17 Second sealing element

[0168] 18 Second spacer

[0169] 19 Support bearing localized on the first end of the shaft

[0170] 20 Support bearing localized on the second end of the shaft

[0171] 20a Thrust-bearing collar

[0172] 21 First sealing insulating barrier

[0173] 22 Second sealing insulating barrier

[0174] 23 Seal between the annular wall of the first sleeve and the first circumferential relief of the shaft

[0175] 24 Seal between the annular wall of the second sleeve and the first circumferential relief of the shaft

[0176] 25 Seat for seal of the annular wall of the first sleeve

[0177] 26 Seat for seal of the annular wall of the second sleeve

[0178] X Longitudinal development axis of the shaft

[0179] F Process fluid

Claims

CLAIMS1. Turbomachine, comprising:- a case (2) defining an inlet chamber (3a) of a process fluid (F), a discharge chamber (5a) of the process fluid (F) and a transit channel (4a) that develops between the inlet chamber (3a) and the discharge chamber (5a) in fluid communication with such chambers (3a, 5a);- at least one rotor assembly (7) comprising: o a shaft (9) developing at least partially through the case (2) and having at least one end (9a, 9b) arranged substantially at one of said chambers (3a, 5a) of the case (2), the shaft (9) being free to rotate about an its own longitudinal development axis (X); o at least one impeller (10) provided with a plurality of blades engaged to the shaft (9) at the transit channel (4a) of the case (2), the blades of the impeller (10) being rotatable, integral with the shaft (9) and about the longitudinal development axis (X) of the latter;- at least one stator assembly (8) comprising: o a sleeve (13, 16) arranged between at least one chamber (3a, 5a) of the case (2) and the end (9a, 9b) of the shaft (9); o a sealing insulating element (14, 17) operatively interposed between the sleeve (13) and one end (9a, 9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the at least one chamber (3a, 5a) with respect to the outside at such end (9a, 9b) of the shaft (9);- at least one support bearing (19, 20) operatively interposed between the end (9a, 9b) of the shaft (9) and the sleeve (13, 16), externally with respect to the sealing insulating element (14, 17);- wherein the sleeve (13, 16) of the stator assembly (8) is movable longitudinally with respect to the shaft (9) between a first position wherein the isolation of the transit channel (4a) and / or of the at least one chamber (3a, 5a) is determined by the sealing element (14, 17) and a second position, wherein such sleeve (13, 16) intercepts a respectivecircumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the at least one chamber (3a, 5a) and the sealing insulating element (14, 17) and allowing the disengagement of the support bearing (19, 20) and / or of the respective sealing insulating element (14, 17) from the shaft (9) without leakage of the process fluid (F) along the respective end (9a, 9b) of the shaft (9).

2. Turbomachine (1 ) according to claim 1 , wherein:- the shaft (9) of the rotor assembly (7) has a first end (9a) arranged substantially at the inlet chamber (3a) of the case (2) and a second end (9b), opposite the first end (9a), arranged substantially at the discharge chamber (5a) of the case (2);- the impeller (10) of the rotor assembly (7) is interposed between the first end (9a) and the second end (9b) of the shaft (9);- the stator assembly (8) comprises: o a first sleeve (13) arranged between the inlet chamber (3a) of the case (2) and the first end (9a) of the shaft (9); o a first sealing insulating element (14) operatively interposed between the first sleeve (13) and the first end (9a) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the inlet chamber (3a) with respect to the outside at the first end (9a) of the shaft (9); o a second sleeve (16) arranged between the discharge chamber (5a) of the case (2) and the second end (9b) of the shaft (9); o a second sealing insulating element (17) operatively interposed between the second sleeve (16) and the second end (9b) of the shaft (9) in such a way as to isolate the transit channel (4a) and / or the discharge chamber (5a) with respect to the outside at the second end (9b) of the shaft (9);- at least one support bearing (19, 20) operatively interposed between each end (9a, 9b) of the shaft (9) and the respective sleeve (13, 16), externally with respect to the corresponding sealing insulating element (14, 17);wherein: the first sleeve (13) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position, wherein the insulation of the transit channel (4a) and / or of the inlet chamber (3a) of the case (2) with respect to the outside is determined by the first sealing insulating element (14) and a second position, wherein the first sleeve (13) intercepts a respective first circumferential relief (11 ) projecting transversally from the shaft (9) between the impeller (10) and the respective first sealing insulating element (14) determining a further first sealing insulating barrier (21 ) between the transit channel (4a) and / or the respective inlet chamber (3a) of the case (2) and the respective first insulating element (14), and allowing the disengagement of the respective support bearing (19) and / or of the respective first sealing insulating element (14) from the first end (9a) from the shaft (9) without leakage of the process fluid (F) along the respective first end (9a) of the shaft (9); the second sleeve (16) of the stator assembly (8) is longitudinally movable with respect to the shaft (9) between a first position, wherein the insulation of the transit channel (4a) and / or of the discharge chamber (5a) of the case (2) with respect to the outside is determined by the second sealing insulating element (17) and a second position, wherein the second sleeve (16) intercepts a respective second circumferential relief (12) projecting transversally from the shaft (9) between the impeller (10) and the respective second sealing insulating element (17) determining a further second sealing insulating barrier (22) between the transit channel (4a) and / or the respective outlet chamber (5a) of the case (2) and the respective second insulating element (17), and allowing the disengagement of the respective support bearing (20) and / or of the respective second sealing insulating element (17) from the second end (9b) from the shaft (9) without leakage of the process fluid (F) along the respective second end (9b) of the shaft (9).

3. Turbomachine (1 ) according to claim 1 or 2, wherein the sleeve (13, 16) comprises a first end (13a, 16a) proximal to the corresponding end (9a, 9b) of the shaft (9) and a second end (13c, 16c) distal to the corresponding end (9a, 9b) of the shaft (9) and arranged internally to the case (2), wherein the second end (13c, 16c) of the sleeve (13, 16) has an annular wall (13d, 16d) which develops transversally, preferably substantially perpendicularly, to the shaft (9) and substantially parallel to the respective circumferential relief (11 , 12) projecting from the shaft (9), at least one seal (23, 24), optionally of an annular shape, in particular an O-ring seal, beingoperatively interposed between the annular wall (13d, 16d) of the second end (13c, 16c) of the sleeve (13, 16) and the corresponding circumferential relief (11 , 12) of the shaft (9) to ensure a sealing at such circumferential relief (11 , 12) when the sleeve (13, 16) is arranged in the second position.

4. Turbomachine (1 ) according to claim 3, wherein the annular wall (13d, 16d) of the second end (13c, 16c) of the sleeve (13, 16) develops transversally towards the shaft (9) according to an extent such that it has at least one striker portion (13e, 16e) abutted on a corresponding striker surface (11a, 11 b) of the respective circumferential relief (11 , 12) of the shaft (9) directed opposite with respect to the impeller (10) and towards the corresponding sealing insulating element (14, 16) when the respective sleeve (13, 16) is in the second position, the corresponding seal (23, 24) being operatively arranged between the striker portion (13e, 16e) of the annular wall (13d, 16d) of the second end (13c, 16d) of the sleeve (13, 16) and the corresponding circumferential relief (11 , 12) of the shaft (9).

5. Turbomachine (1 ) according to claim 4, wherein the striker portion (13e, 16e) of the annular wall (13d, 16d) of the second end (13c, 16c) of the sleeve (13, 16) has at least one seat (25, 26) for the housing of the respective seal (23, 24), such seal (23, 24) occupying the respective seat (25, 26) and partially protruding therefrom in such a way as to remain compressed against the corresponding circumferential relief (11 , 12) of the shaft (9) when the sleeve (13, 16) is in the second position, ensuring the sealing at such circumferential relief (11 , 12).

6. Turbomachine (1 ) according to any one of claims 3 to 5, wherein the first end (13a, 16a) of the sleeve (13, 16) has an annular edge (13b, 16b) projecting outwardly, transversally, optionally perpendicularly, to the longitudinal development axis (X) of the shaft (9), at least one spacer (15, 18) being arranged to remain between the respective annular edge (13b, 16b) of the sleeve (13, 16) and the case (2) and to lock the latter on the case (2) itself, optionally, the removal of the spacer (15, 18) from the sleeve (13, 16) allowing the movement of the latter with respect to the shaft (9) along a direction substantially parallel to the longitudinal development axis (X) of the latter between the first and the second position.

7. Method for partially dismantling a turbomachine (1 ) according to any one of the preceding claims, comprising the following steps:(i) stopping the operation of the turbomachine (1 ) in such a way as to allow the access to one or more of its components;(ii) removing a support bearing (19, 20) from a respective end (9a, 9b) of the shaft (9) of the rotor assembly (7);(iii) releasing the respective sealing insulating element (14, 17), at least with respect to the shaft (9);(iv) releasing the respective sleeve (13, 16) with respect to the case (2) and to the shaft (9);(v) moving the respective sleeve (13, 16) longitudinally along the shaft (9) between a first position wherein the insulation of the transit channel (4a) and / or of the respective chamber (3a, 5a) of the case (2) with respect to the outside is determined by the corresponding sealing insulating element (14, 17) and a second position, wherein the respective sleeve (13, 17) intercepts the respective circumferential relief (11 , 12) projecting transversally from the shaft (9) between the impeller (10) and the respective sealing insulating element (14, 17) determining a further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective insulating element (14, 17);(vi) locking the respective sleeve in the second position to maintain the respective further sealing insulating barrier (21 , 22) between the transit channel (4a) and / or the respective chamber (3a, 5a) of the case (2) and the respective first sealing insulating element (14, 17);(vii) removing the respective sealing insulating element (14, 17) from the shaft (9).

8. Method for dismantling according to claim 7, wherein the sequence of steps for dismantling (i)-(vii) is performed for each of the ends (9a, 9b) of the shaft (9) of the rotor assembly (7) of the turbomachine (1 ).

9. Method for dismantling according to any one of the two preceding claims, when claim 7 depends on claim 6, wherein the release of the sleeve (13, 16) with respect to the case (2) and to the shaft (9) is carried out by releasing and removing the respective spacer interposed between the annular edge (13b, 16b) of the first end (13a, 16a) of the sleeve (13, 16) and the case (2).

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