TURBINE PLANT

DESCRIPTION

TECHNICAL FIELD Embodiments of the subject matter disclosed herein correspond to protection systems for gas turbine air intakes and gas turbine plants.

BACKGROUND ART

A gas turbine has an intake for air to be used as oxidant of fuel in its combustor or combustors. A gas turbine plant typically comprises an air inlet section for delivering air to the air intake of the gas turbine.

The air inlet section typically comprises a protection system in order to avoid that large pieces of debris enter the intake of the gas turbine and damage the gas turbine.

It is to be noted that, in the field of Oil & Gas, gas turbines are very expensive and therefore it is important to avoid damages to them.

A protection system for a gas turbine is known from US patent application published as US2015/0089908A1.

This document concentrates on the structure of the protection system and of its screen components. According to the solution of this document, the protection system is secured (e.g. welded) inside an air inlet section and screen components are secured (e.g. welded) to frames of the protection system.

This document does not address the problem of maintaining the protection system, in particular of repairing screen components when damaged by debris.

The structure and the construction of such protection system and of its screen components imply that repairing requires some expertize and a rather long time. During repairing operations of the protection system the gas turbine must be stopped; therefore, a long repair time means a long downtime of the gas turbine plant which is very expensive in the field of Oil & Gas.

SUMMARY Therefore, there is a general need for improving protection systems for gas turbine air intakes.

First embodiments of the subject matter disclosed herein relate to protection systems for air intakes of gas turbines.

According to such first embodiments, the protection system comprises a screen assembly; the screen assembly comprises a framework with a connection part for releasable mounting thereof, and one or more screen components releasably mounted to the framework.

Second embodiments of the subject matter disclosed herein relate to gas turbine plants.

According to such second embodiments, the gas turbine plant comprises a gas turbine and a protection system for an air intake of the gas turbine; the protection system comprises a screen assembly; the screen assembly comprises a framework with a connection part for releasable mounting thereof, and one or more screen components releasably mounted to the framework.

BRIEF DESCRIPTION OF DRAWINGS The accompanying drawings, which are incorporated herein and constitute an integral part of the present specification, illustrate exemplary embodiments of the present invention and, together with the detailed description, explain these embodiments. In the drawings:

Fig. 1 shows a schematic view of an embodiment of a gas turbine plant with a protection system,

Fig. 2 shows a three-dimensional view of an embodiment of a screen assembly, Fig. 3 shows a three-dimensional partial view of an embodiment of a screen assembly (i.e. the one of Fig. 2) without screen components, and

Fig. 4 shows the construction of an embodiment of a protection system with the screen assembly of Fig. 2 being an elbow-shaped feed assembly of an air inlet section for delivering air to an air intake of a gas turbine.

DETAILED DESCRIPTION

The following description of exemplary embodiments refers to the accompanying drawings.

The following description does not limit the invention. Instead, the scope of the invention is defined by the appended claims.

Reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

The embodiment of gas turbine plant of Fig. 1 is generally indicated at 1.

The gas turbine plant 1 comprises a gas turbine 2 and, at least, an air inlet section for delivering air to the air intake of the gas turbine 2 (see the arrows in the figure). According to this embodiment, the air inlet section comprises, at least, a filter assembly 3, a silencer assembly 4 and a feed assembly 5; air enters the filter assembly 3, flows first through the filter assembly 3, then through the silencer assembly 4, finally through the feed assembly 5, exits the feed assembly 5 and enters the intake of the gas turbine 2.

The filter assembly 3 is designed to filter air.

The silencer assembly 4 is designed to reduce noise. The feed assembly 5 is designed to feed air.

In general, a gas turbine plant comprises a gas turbine as well as systems, assemblies and devices connected directly or indirectly to the gas turbine.

According to the plant of Fig. 1, the feed assembly 5 embodies also a protection system comprising a screen assembly 6; the protection system avoids, for example, that debris from silencing panels of the silencer assembly 4 enter the intake of the gas turbine 2.

The feed assembly 5, i.e. the embodiment of protection system, comprises a housing 50 with an air inlet 51, an air outlet 52 and an air duct 53 fluidly connecting the air inlet 51 and the air outlet 52, as well as the screen assembly 6. According to this embodiment, the housing 50 is elbow- shaped.

According to this embodiment, the screen assembly 6 is located at the air inlet 51.

Screen assembly 6 may have the structure shown in Fig.s 2 and 3; in Fig.s 2 and 3, the screen assembly is generally indicated at 100.

The screen assembly 100 comprises a framework and a plurality of screen components (for example a number in the range from two to twelve) mounted to the framework. In particular, the framework is a supporting framework, more specifically a self- supporting framework. In particular, the screen components are screen panels (labelled 130 and 140 in Fig. 2).

The framework of the screen assembly 100 has at least one connection part for mounting the screen assembly 100 to one or more other components of a gas turbine plant, for example plant 1 of Fig. 1. The connection part may be a flange (labelled 150 in Fig. 2), i.e. a connection flange.

Advantageously, the framework may be easily mounted and dismounted, i.e. are releasably mounted; screws and/or bolts may be used for this purpose. Advantageously, the screen components may be easily mounted and dismounted, i.e. are releasably mounted; screws and/or bolts may be used for this purpose. According to the embodiment of Fig. 2, the framework consists of the combination of a flange 150, a first frame 110 and a second frame 120 that are both fixed to the flange 150. The frame 110 is directly fixed to the flange 150. The second frame 120 is indirectly fixed to the flange 150; in particular, it is fixed to the flange 150 through a set of connection bars 160. Therefore, the first frame 110 and the second frame 120 are indirectly fixed to each other.

According to the embodiment of Fig. 2, the first frame 110 is rectangular and consists of the combination of four peripheral bars 111 (fixed together) and a set of cross-bars 112; the second frame 120 is rectangular and consists of the combination of four peripheral bars 121 (fixed together) and a set of cross-bars 122; the first frame 110 and the second frame 120 are identical.

According the embodiment of Fig. 2, the second frame 120 is offset with respect to the first frame 110 both in transversal and longitudinal directions. In particular, considering the flow of the air, the first frame 110 is a front frame and the second frame 120 is a rear frame. In particular, the first frame 110 is an upper frame and the second frame 120 is a lower frame.

According the embodiment of Fig. 2, a first plurality of screen panels 130 (according to this embodiment, five panels) are adjacent to each other; in particular, each of them is releasably mounted to the first frame 110 (peripheral bars 111 and/or cross-bars 112) independently from each other.

According the embodiment of Fig. 2, a second plurality of screen panels 140 (according to this embodiment, five panels) are adjacent to each other; in particular, each of them is releasably mounted to the second frame 120 (peripheral bars 121 and/or cross-bars 122) independently from each other. Due to the positions of the frames 110 and 120, the second plurality of screen panels 140 is offset with respect to the first plurality of screen panels 130 both in transversal and longitudinal directions. Advantageously, all the screen panels 130 and 140 are arranged to be dismounted from and mounted to the frames of the framework (thanks to screws and/or bolts) while the framework is mounted; as it will be explained afterwards, at least one opening in the framework and at least one hatch in a housing may be provided for allowing mounting and dismounting.

According the embodiment of Fig. 2, the screen components are screen panels (labelled 130 and 140) comprising a rectangular peripheral frame (labelled 131 and 141) and a rectangular portion of wire mesh (labelled 132 and 142) fixed to the peripheral frame.

Advantageously, the peripheral frame of the screen components is arranged for mounting the screen component to the framework, in particular to the frame or frames of the framework.

Advantageously, all the screen components are identical.

Fig. 4 shows a feed assembly 200 that, similarly to the feed assembly 5 in Fig. 1 , embodies also a protection system comprising the screen assembly 100 of Fig. s 2 and 3.

The feed assembly 200, i.e. the embodiment of protection system, comprises a housing 250 with an air inlet 251, an air outlet 252 and an air duct 253 fluidly connecting the air inlet 251 and the air outlet 252, as well as the screen assembly 100. In particular, the housing 250 is elbow- shaped. The framework of the screen assembly 100 is releasably mounted (for example, by means of screws and/or bolts) to a flange 255 of the air inlet 251; according to an alternative embodiment, for example, the framework of the screen assembly 100 may be releasably mounted to a flange 256 (not shown) of the air outlet 252.

According to the embodiment of Fig. 4, the flange 150 of the screen assembly 100 is mounted between the inlet flange 255 of the feed assembly 200 and an outlet flange of a silencer assembly. According to the embodiment of Fig. 4, the housing 250 has an inspection hatch 254. The hatch of the housing may be used not only for checking the status of the screen components but also for replacing (or repairing) them in case of damage. The hatch of the housing may be sufficiently large that an operator may totally or partially enter into the housing. Safety reasons strongly recommend against opening the hatch of the housing and even more entering (totally or partially) into the housing while the gas turbine is in operation.