Abstract: The present invention relates to a method for treating organs subject to erosion by liquids, in particular vapour turbine components, which contemplates laser plating with a cobalt-based alloy comprising chromium from 28 to 32% by weight; tungsten from 5 to 7% by weight; silicon from 0.1 to 2% by weight; carbon from 1.2 to 1.7% by weight; nickel from 0.5 to 3% by weight; iron from 0.01 to 1% by weight; manganese from 0.01 to 1% by weight; molybdenum from 0.2 to 1% by weight; possible impurities or other elements from 0 to 0.5% by weight and cobalt the complement to 100%.

Abstract: An axial thrust balancing system (10) for a centrifugal compressor (12), having improved safety characteristics, the centrifugal compressor (12) comprising a rotor (14) having impellers (16) adjacent to each other and connected by a shaft (18), the rotor (14) rotating in a stator (20), the centrifugal compressor (12) additionally including a balancing piston (22), a balancing line (24) being provided between an intake of a first compression stage and an area downstream of the balancing piston (22); this system (10) comprises an intake mechanical gas seal (26) around the shaft (18) upstream of the first compression stage and an outlet mechanical gas seal (28) downstream of the balancing piston (22), the balancing line (24) being closable by means of blocking elements (32).

Abstract: A cylindrical blade for a rotor of the purely radial type of a centrifugal compressor with a medium flow coefficient comprises a first surface (3) of the pressure side and a second surface (5) of the suction side of equal curvature, both having generatrices parallel to the axis (Z) of rotation of the rotor, in which the line (7) of curvature of the said surfaces (3, 5) is defined, in a Cartesian reference system, by the ratio between the coordinates of a discrete set of points (9) belonging to the line and the outer radius (R) of the rotor (10).

Abstract: Stator blading (10) of return channels for two-dimensional centrifugal stages of a multi-stage centrifugal compressor with improved efficiency, of the type comprising a plurality of blades (20) disposed circumferentially equally spaced on a ring (12) which surrounds a rotor of the compressor, these blades (20) each having a cross-section in the shape of a half-moon formed by a concave area (21) and a convex area (22), these concave (21) and convex (22) areas being connected to one another such as to determine a trailing edge (24) and a leading edge (23) on an inner radius (R); the profile of the concave area (21) of each blade (20) is produced by connecting to one another points which have particular Cartesian co-ordinates relative to a system of axes which are at right-angles to one another, of x-co-ordinates (X) and y-co-ordinates (Y) with an origin (O) located on the axis of rotation.

Abstract: A valve with ball of controlled deformation for fluid shut-off comprising an external containment body (11), inside which is arranged a shutter element (13), movable between a closure position and an opening position of the valve, the shutter element cooperating with one or more seats (12) and providing for seal elements with respect to the containment body and to the shutter element, in which the shutter element provides for yielding zones (15a) in its spherical portions (15) disposed downstream of the seats with respect to a pressure zone. Preferably the yielding zones are provided by notches (19) produced on surface zones of the shutter elements in correspondence with the spherical portions.

Abstract: A simplified support device (110) for nozzles (112) of a gas turbine stage, of the type in which the support device (110) is interposed in a rotor of the gas turbine, between an upstream blading disc (122) and a downstream blading disc (124) of the nozzles (112), and is provided with honeycomb-type alveolar seals (120); the nozzles (112) of the gas turbine stage comprise an annular body which is divided into nozzle segments (112) and the honeycomb-type alveolar seals (120) are anchored directly to these nozzle segments (112).

Abstract: A method for production of a rotor for centrifugal compressor, wherein the said rotor is produced from a monolithic disc, which is provided with a central hole. The method consists of use, within an isolating medium, of at least one first electrode which has polarity opposite the polarity of the rotor, wherein the said first electrode operates starting from the outer diameter of the monolithic disc, in order to produce the blades and the cavities of the said rotor, and wherein the processing takes place with a continuous path, consisting of a first step of roughing, followed by a second step of finishing with a tool which has a shape similar to that of the electrode used for the first roughing step, in order to produce an accurate geometry of the blades.

Abstract: A flange (20) for connection between an axial compressor and high-pressure rotor disc unit (14) in a gas turbine (10), wherein the flange (20) has a body (22) with a frusto-conical shape which is joined to a shaft (12) of the axial compressor by means of a hub (24) which has a cylindrical shape and which, at the larger base of the frustum of the cone of the body (22) is connected to the rotor disc unit (14) by means of an extension (26) of the hub in the form of a circular ring, a circumferential recess (28) provided in a surface (29) of the extension (26) which faces the rotor disc unit (14) being connected by interference with a projection, which is complementary to the recess and is provided on the rotor disc unit (14); the body (22) has an outer generatrix which is inclined relative to the direction at right-angles to the axis (X) by an angle &agr;1 of between 25° and 35° and an inner generatrix which is inclined by an angle &agr;2 of between 12° and 18°.

Abstract: A system for remote diagnosis of the state of wear of the suction and delivery valves of reciprocating compressors comprises at least one piezoelectric seismic sensor, applied to each cylinder of the compressor. The sensor transforms the vibrations generated by the noise of the valves into an electric signal. By appropriate amplification and filtering, the envelope of the resulting narrow band signal is obtained. The signal obtained is then digitized, and transmitted to a remote diagnostics center for monitoring.

Abstract: A device (10) for continuous regulation of the gas flow rate processed by a reciprocating compressor, wherein the reciprocating compressor has at least one first compression piston (35), which is associated with a first cylinder (51), and can create a pressure which is variable over a period of time, and a second piston (13), which acts inside a second cylinder (52), which is in free communication with the said first compression cylinder (51), associated with the said first piston (35), and which acts on an additional dead space (11). The device includes a third fluid mechanics cylinder (12), which moves the said piston (13) of the dead space (11), wherein the third fluid mechanics cylinder (12) is activated by means of a compressed fluid, supplied by means of an independent hydraulic system (14), in order to obtain continuous variation of the dead space (11).

Abstract: A cooling system for gas turbine stator nozzles, wherein each of the vanes which belong to the nozzles of the gas turbine has a concave surface and an opposite convex surface, which cooperate in order to define the outer shape of the vane, and wherein the surface of the vane has a plurality of cooling holes, at appropriate points of the surface itself of the vane. In this system, the cooling hole relative to the outlet edge of the vane is provided with an intake section and an outlet section, which are shaped such that the cooling hole has a cross-section which is variable in a direction which is radial relative to the vane.

Abstract: A casing (30) for centrifugal compressors comprises a substantially cylindrical body (31) which is internally hollow and has its own central axis (32). The internal cavity of the casing (30) has an internal central axis (34) substantially coinciding with the axis of rotation of the machine and offset, in a vertical direction, with respect to the central axis (32) of the external surface of the cylindrical body (31) so that the casing (30) has an eccentric shape, having portions of different thickness, so as to create zones where the attachment point for the gas inlet counterflange (35) and outlet counterflange (36) can be formed. The invention also relates to a method for the manufacture of a casing (30) for centrifugal compressors.

Abstract: A combustion chamber for gas turbines comprises an inner liner (12) and an outer liner (11), wherein the inner liner (12) is substantially concentric relative to the outer liner (11), such as to define an annular inner space (30), and wherein a shield (13) is provided at the output of each of the burners. The specific feature of the invention consists in the fact that each of the shields (13) comprises a single metal plate part, and that the liners (11, 12) have a plurality of holes (20, 21), in sections adjacent to the longitudinal development of the shield (13), such as to define gaps (60, 61) for the circulation of air.

Abstract: A device for securing blades of the first stage of a gas turbine wherein the blades having cooling passages for flowing cooling air from the blade roots towards the blade airfoils. A plurality of plates, each of which has at least one U-shaped projection, engages a corresponding U-shaped groove in the surface of a rotor disc of the first stage. Each plate is interposed between two adjacent first stage blades to secure the blades axially. Second stage turbine blades are secured against axial movement by a plurality of plates, each of which is interposed between the end portion of the foot of a corresponding blade and the turbine disc. Each of the latter plates is provided with ends to secure the blade axially.

Abstract: A screw-type pumping unit (51) for treatment of fluids in several phases comprises a case (54) which contains a pumping chamber (62), inside which there are accommodated at least two screws (70a, 70b), one of which (70a) is a drive screw, and supports at one of its ends a first gear (108a), which engages with a second gear (108b), which in turn is supported at one end of a driven screw (70b). The first and the second gear (108a, 108b) are contained in a casing (110) which is fitted onto them, and is provided with at least two through holes (112, 114) produced in two substantially opposite portions, through one of which oil can be admitted into the casing (110), and wherein the oil can be discharged through the other through hole (114), such that the casing (110), together with the gears (108a, 108b), forms a gear pump which can keep the lubrication oil of the pumping unit (51) circulating.

Abstract: A device for positioning of nozzles of a stator stage and for cooling of rotor discs in gas turbines, of the type including nozzle segments consisting of several airfoils. Each nozzle segment is connected at its top to an outer ring to define a chamber containing cooling air and is positioned at its base on an inner ring. The nozzle segments form a circumferential array about the axis of the gas turbine. In each airfoil of the nozzle segment, there is provided at least one tube, which is inserted in a corresponding duct inside the airfoil for delivering cooling air to the first and second stage discs.

Abstract: A pre-mixing chamber (10) for gas turbines, wherein the gas turbine is of the type which comprises at least one compressor connected to the turbine, and a combustion chamber, wherein the combustion chamber has a converging portion (12), positioned such as to give rise to combustion inside the combustion chamber, and wherein the pre-mixing chamber (10) has a plurality of pipes (19) provided with holes (20), which open into the combustion chamber on a front portion of the body of the pre-mixing chamber (10), in order to generate a series of pilot flames, which are appropriately regulated, in order to stabilise a main flame, which is primed inside the combustion chamber, in which a front area of the converging portion (12) of the pre-mixing chamber (10) has at least one circular groove (28) provided at the holes (20) which belong to the pies (19).

Abstract: The present invention relates to a liquid fuel injector (10) for burners in gas turbines, of the type used inside burners which are provided with a pre-mixing chamber (62) and an element (13) to create turbulence in the flow of compressed air obtained from the compressor of the gas turbine. The injector (10) comprises a body (11) which ends in a tip (12) and is provided with at least one duct (25) for passage of the fuel, and ducts (48, 58) for the inflow of compressed air from the compressor of the turbine, wherein the duct (25) for the fuel and the ducts (48, 58) for the compressed air end in respective outlet holes. The tip (12) of the injector (10) ends at the median part of the converging portion (61) of the pre-mixing chamber (62).