Steam turbine cooling method

FIELD: machine engineering.

SUBSTANCE: steam-turbine plant with steam turbine, comprising a steam inlet portion, a steam outlet portion, and a blade grid located in the turbine housing axially between the first two sections, as well as with an exhaust device to divert the cooling fluid from the turbine casing. The coolant inlet with locking and opening shut-off is provided. The shut-off is installed upstream of the steam outlet portion with respect to the flow direction of the working steam through the steam turbine during normal operation. The shut-off is activated by the cooling fluid after the power is turned off to a cooling mode below the operating temperature in the turbine housing. The steam-turbine plant comprises a valve through which the cooling fluid passes. The valve contains a drying device for draining the valve. This device comprises a drainage pipeline and a branch connected hydraulically to the inlet for the cooling fluid. Method for cooling a steam turbine with a turbine casing, in which after disconnecting power the inlet for the cooling fluid is hydraulically connected to the turbine casing pass with absorption of heat through the inlet for the cooling fluid, the incoming cooling fluid, in particular air, by means of an exhaust device through the turbine casing in the direction of the working steam flow through the steam turbine in the normal operating mode. The cooling fluid is passed through the valve. The valve comprises a drying device through which a cooling fluid is passed.

EFFECT: reliable cooling of the gas turbine.

11 cl, 3 dwg

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to a multilayered thermal barrier coating on components of a hot path of energy gas turbine installations of high power. The multi-layered thermal barrier includes a basic metal sublayer, made from a nickel-based alloy, an upper ceramic thermal barrier layer and an additional metal thermal barrier sublayer between the basic sublayer and the ceramic layer. The basic metal sublayer contains 18…25% of cobalt, 14…20% of chrome, 11…14% aluminium and 0.1…0.7 yttrium. The upper ceramic thermal barrier layer is made from a material based on zirconium dioxide ZrO2, partially stabilised 6…8% by yttrium oxide weight. The additional metal thermal barrier layer is made from a nickel-based alloy, containing 18…25% of cobalt, 14…20% of chrome, 10…13% of aluminium and 0.1…0.7 of yttrium.

EFFECT: protection against an impact of high temperatures, erosion and corrosion by the formation of long-lasting thermal barrier coatings.

1 ex

FIELD: process engineering.

SUBSTANCE: invention relates to repair of gas turbine blades with at least one worn-out root with one lateral surface that features insufficient size. Note here that application of material on at least one surface is performed so that root features overdimension. Then, the root is machined to remove material from at least one side surface to rated size. Adhesive material is used for recovery of rated size of the root. Note here that adhesive material application is performed for recovery of turbine blade heat-isolation coating system comprising adhesive layer and heat-isolation layer.

EFFECT: efficient recovery with lower costs and material input.

12 cl, 6 dwg

FIELD: metallurgy.

SUBSTANCE: alloy contains the following, wt %: up to 20 of sum of Co and Fe, between 17 and 21 Cr, between 0.5 and 3 of sum of Mo and W, not more than 2 Mo, between 4.8 and 6 Al, between 1.5 and 5 Ta, between 0.01 and 0.2 of sum of C and B, between 0.01 and 0.2 Zr, between 0.05 and 1.5 Hf, between 0.05 and 1.0 Si, and between 0.01 and 0.5 of sum of at least two elements of actinides and rare-earth metals, such as Sc, Y and lanthanides. Content of each element is not more than 0.3. Alloy is used in high-temperature components representing rotating blades, guide vanes, heat shields, seals or parts of a combustion chamber in gas turbines, as well as process alloy for repair welding and/or cladding of such high-temperature components.

EFFECT: alloy has high properties of stability to oxidation, resistance to high-temperature corrosion, strength and ductility, weldability.

21 cl

FIELD: metallurgy.

SUBSTANCE: method to produce a blank of a blade of gas turbine engines (GTE) with ultra-fine grain structure from titanium alloys includes preliminary heating of the blank to temperature below temperature of polymorphous conversion and treatment by means of multiple intensive plastic deformation with changing of deformation directions in several cycles. Treatment is carried out under isothermic conditions at identical temperature of the blank and the punch. In each cycle deformation is carried out at temperature of alloy annealing according to stages, which include setting of the cylindrical blank in the closed punch, open setting with production of the blank in the form of a disc, flattening to the disc rib in the closed punch for production of the blank with the square section, its setting in the closed punch to the cylindrical blank. Number of treatment cycles is determined based on achievement of the extent of accumulated deformation of at least five. Then closed setting of the blank is carried out at the temperature of 50-100°C below the alloy annealing temperature, squeezing into the cylindrical blank, having two different diameters of cross section for a blade foot and airfoil, and flat stamping of the blade blank.

EFFECT: homogeneous ultra-fine grain structure is produced in a blade blank, providing for high physical and mechanical and operating properties of a blade.

2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to machine building. Proposed method comprises the following jobs: collecting coordinates of points on parts surface. Note here that combination of points forms a cloud, comparing known profile with said cloud to define part bulged or thinner zones, forming said profile by morphing to allow formed profile to interpolate said cloud. Note here that profile deformation defines the function of morphing and profile and comprises comparison of part every bulged or thinner zone with elementary configurations, each representing grid section simulating the profile and points simulating points of aforesaid cloud. Note here that elementary configuration of deformation are classified in data base. Note also that data base related, for every said deformation elementary configuration, the parameters of morphing function. Machining of damaged part is performed at appropriate machine with parameters defined subject to morphing function.

EFFECT: reconditioning of blade aerofoil using adequate model of part current state.

6 cl, 1 ex, 5 dwg

FIELD: machine building.

SUBSTANCE: methods of designing axial or radial turbine blading whereby turbine cascade blade channel is divided into two sections. Channel meridional outline height is varied or not on entire section of bend in blade channel or its part. Second section of acceleration with additional bend or without it comprises skew edge of blade channel wherein said height is decreased toward channel outlet to verge coupled with mouth cross-section. Behind said verge, height is varied to increase open flow area. Narrow area of every blade channel is formed. At second acceleration section, arranged are multiple possible locations of mouth are including that whereat mouth area center is located on turbine cascade front outlet cross-section. Ring ledges are arranged behind outlet area, on periphery, or nearby barrel, or on periphery and barrel at a time.

EFFECT: higher efficiency, lower hydraulic losses.

8 cl, 14 dwg

FIELD: machine building.

SUBSTANCE: hydraulic control unit for blades (2) of impeller (1) of the axial fan comprises regulating cylinder (6), which has first chamber (11) and second chamber (12) on both sides of internal moving piston (7); each of the chambers is linked with control channels (A, B) through connections (14, 15). Control channels (A, B) are connected to the 4-stroke valves. Both supply channel (P) leading to one of control channels (A) and outlet channel (T) connected to another control channel (B) are split into two parallel branches (P1/A1, P2, A2, T1/B1, T2/B2). There are two auxiliary 4-stroke valves (23), (33), each of which is built into one of parallel branches (P1, A1 or P2, B2) and (T1, B1 or T2, B2). There is seated valve (24), (25), (34), (35) closing with a spring force and installed in each branch (A1, A2) of one control channel (A) and in each branch (B1, B2) of the other control channel (B) between relevant connections (14), (15) and corresponding 4-stroke valves (23), ( 33).

EFFECT: control of the blades that ensures that even in case of power failure it is possible to keep the blades in their last position before the incident until another control unit takes over control of the blades position after switching over of the mains supply.

11 cl, 4 dwg

FIELD: metallurgy.

SUBSTANCE: nickel-based superalloy is proposed with a strengthening gamma-line-phase, containing the following components: up to 20 wt% Co, from 12 to 14 wt % Cr, from 1 to 2 wt % Mo, from 1.4 to 2.8 wt % W, from 5.1 to 5.9 wt % Al, from 1.1 to 1.6 wt % Ti, from 3 to 7 wt % Ta, from 0.01 to 0.3 wt % C+Zr+B, from 0.05 to 1 wt % Hf, from 0.05 to 1 wt % Si, and from 0.01 to 0.2 wt % of rare earth elements. Also alloy application as a hot machine component is proposed.

EFFECT: alloy is characterised with high resistance to high-temperature corrosion, oxidation, high compatibility with coatings, phase stability, high resistance to creepage and low density.

12 cl, 1 dwg

FIELD: machine building.

SUBSTANCE: impeller of centrifugal compressor includes the main and cover discs and blades located between them and forming interblade channels; at that, in the middle part of the blade, near each of the blades there made is a slot; one end of each slot is located near the corresponding disc; the other end of each slot is located closer to impeller outlet, and each slot makes an angle of 12-18 degrees with the corresponding disc.

EFFECT: reducing hydraulic losses in impeller and increasing the efficiency of centrifugal compressor.

2 dwg

FIELD: machine building.

SUBSTANCE: procedure for preparation of rotating element for longer service life of bearing consists in: application of metal material on surface of rotating element orthogonally to lengthwise axis of rotating element, also, contents of chromium in material is less, than contents of chromium in rotating element. Further, the procedure consists in treatment of surface of metal material orthogonal to axis of the rotating element. The rotating element increasing service life of the bearing consists of: the rotating element; surface of metal material orthogonal to lengthwise axis of the rotating element with contents of chromium, less than the rotating element; a boundary layer between surface of metal material and the rotating element orthogonal to lengthwise axis of the rotating element; also, surface of metal material corresponds to supporting surface taking axial load; surface of metal material has contents of chromium below 2.2 percents.

EFFECT: increased service life of bearing; finished supporting surface eliminates problems of fluffiness.

10 cl, 4 dwg

Steam turbine // 2508452

FIELD: machine building.

SUBSTANCE: steam turbine comprises working blades and diaphragm outer ring arranged on outer side of said blades. Every working blade comprises end flange, moisture catch grooves, drop removal bore and drain guide flute. End flange is arranged at working blade end to get in contact with end flanges of adjacent working blades. Moisture catch grooves are made at blade back in lengthwise direction. Moisture removal bore communicate end flange outer surface on diaphragm outer ring side and end flange inner surface on working blade inner side. Drain guide flute communicate moisture catch groove ends on end flange side surface with moisture catch bore. Drain guide flute bottom has inclination to blade rear and in steam turbine radial direction. Diaphragm outer ring has drain pocket facing the moisture removal bore.

EFFECT: higher removal of moisture from working blade.

9 cl, 15 dwg

FIELD: power engineering.

SUBSTANCE: steam turbine comprises a diaphragm consisting of an inner ring, an outer ring and airfoils stretching between them. The airfoil comprises at least one channel of moisture removal, stretching along a part of the airfoil length and having at least one inlet hole, which communicates by the flow with the steam path passing through a row of airfoils and between adjacent airfoils, and at least one channel of inlet, stretching along a part of the length of the airfoil along the axis downstream at least one channel of the moisture removal channel and comprising at least one outlet hole for inlet of steam into the steam path. In the outer ring of the diaphragm there is an outer cavity, which represents a cavity for separation of steam/moisture. Steam and moisture removed via a channel of moisture removal arrive into the cavity. The cavity communicates along the flow with the channel of steam inlet for repeated inlet of steam separated in the cavity, into the steam path.

EFFECT: problem of moisture removal is solved, which reduces risk of erosion, using the invention makes it possible to avoid reduction of efficiency taking place as a result of leakage or removal of steam from a flow path because of its ingress.

8 cl, 11 dwg

FIELD: engines and pumps.

SUBSTANCE: exhaust casing of gas-turbine engine includes annular groove with a hole, in which drain in the form of cylindrical tubular housing is arranged. Drain is meant for removal of liquid accumulated in the groove. Drain includes skirt made on the end of cylindrical housing and caulked in the hole of casing groove to attach the drain to the casing. The other subject of the present invention is gas-turbine engine, and namely jet turbine engine containing exhaust casing described above.

EFFECT: invention allows simplifying the erection of the drain on exhaust casing.

9 cl, 4 dwg

FIELD: engines and pumps.

SUBSTANCE: moist-steam turbine nozzle blade comprises body. Said body is arranged between inlet and outlet edges and features convex and concave surfaces. Medium section of concave surface is covered by guide plate to make a channel and injected steam exhaust slot located on body outflow edge side. Medium section of body concave surface and guide plate on channel and injected steam exhaust slot side are provided with heat-insulation layer.

EFFECT: higher intensity of moisture evaporation by injected steam.

2 dwg

FIELD: machine building.

SUBSTANCE: proposed assembly comprises multiple nozzles arranged between blade steps, groove and extraction chamber, as well as first and second bores. Said groove is located upstream of blade one step and between blade step and step of nozzles located upstream of blade step and adjoining thereto. First bore extends to extraction chamber to allow bidirectional communication between groove and extraction chamber. Second bore extends from extraction chamber via diaphragm assembly outer surface to allow bidirectional communication between extraction chamber and area outside of diaphragm assembly. Another invention of the set relates to steam turbine with above described diaphragm assembly.

EFFECT: higher reliability and longer life.

10 cl, 6 dwg

FIELD: machine building.

SUBSTANCE: procedure for fabricating blade of guiding mechanism of stem turbine consists in connection of padding with blade body by means of contact weld and electron-beam weld. The padding is connected with the blade body by contact welding at the exit edge of the blade, while slit channels are arranged between sections of contact welding along the exit edge of the blade.

EFFECT: simplified fabrication of blade of guiding mechanism of steam turbine.

1 cl, 2 dwg

FIELD: machine building.

SUBSTANCE: cylinder of medium pressure in steam turbine consists of case with chamber, of steam inlet connected to cavity of lower pressure via separator, of guiding mechanism of first step with working blades arranged behind it with inter-rim gap, of ferrule of stator with radial packing positioned over band of working blades secured to guiding mechanism of first step. The ferrule forms a circular cavity with case of cylinder, while with diaphragm of second step it forms an open inter-step gap communicated with circular cavity. Separate circular chambers positioned opposite the inter-rim gap of the first step are made in the ferule, opposite to an inlet edge of the working blades band of this step and over pins of the working blades between the steps of radial packing. The separate circular chambers are communicated with the circular cavity of the case by means of drain channels beneath the ferrule. Outlet sections of the drain channels are arranged in the ferrule with set-off in a sequence corresponding to the position of the circular chambers in the ferrule. To external surface of the ferrule at a back end wall there is attached a circular screen separating a part of the circular cavity of the case with the outlet sections of the drain channels from the part of the circular cavity with an open gap between the first and the second step. Additional circular chambers located opposite to packing collars of the band of the first step blades can be made in the ferrule.

EFFECT: decreased abrasive wear of over-band packing and leaks through it in first step, also increased reliability of working wheel due to reduced wear of working blade pins, thus increasing service life of cylinder of medium pressure at presence of abrasive flows in it; improved indices of efficiency and reliability of turbine at continuous operation in whole.

2 cl, 5 dwg

FIELD: engines and pumps.

SUBSTANCE: invention refers to turbine industry and can be used at the last stages of wet-steam turbines. Blade of nozzle grid of wet-steam turbine includes the wing with inlet and outlet edges, which is made in the form of convex and concave surfaces, as well as injected steam channel. Middle part of concave surface is covered with the covering plate so that the outlet slot of injected steam channel is formed on the outlet edge side. Injected steam channel is formed with the middle part of concave surface and the covering plate on the side of the wing inlet edge. Outlet slot of the channel is located relative to outlet edge of the wing at the distance equal to 0.1…0.4 of the distance between its inlet and outlet edges.

EFFECT: invention is aimed at increasing moisture separation efficiency.

2 dwg

Moist-steam turbine // 2360132

FIELD: motors and pumps.

SUBSTANCE: moist-steam turbine contains ring-shaped case forming steam inlet together with peripheral and central sections, correspondingly. There is a circular cowling in the central steam inlet section. Together with case, this cowling forms moisture intake channel, which is open from the side of peripheral steam inlet section. The moist-steam turbine contains also moisture collector made up from two grooves at different sides of moisture intake channel. The groove in the said case is made on the radial level exceeding the radial level of the groove made in the cowling. So the formed double-channel moisture collector is linked with steam inlet of moisture intake channel and with bleeding chamber located behind the case by means of holes made in the said case. The coarse moisture precipitates on the case in peripheral section of the steam inlet. Thus, the water film locating both from the upper and lower halves of the case is drawn into the moisture intake channel under the action of steam flow. After that the moisture gets into the moisture collector grooves and then, to bleeding chamber through the holes due to pressure drop. The disclosed by the invention structure of moist-steam turbine allows for collecting moisture from both upper and lower halves of steam inlet case.

EFFECT: improved effectiveness of moisture removal from moist-steam turbine and increased cost effectiveness.

2 dwg

Moist-steam turbine // 2360131

FIELD: motors and pumps.

SUBSTANCE: moist-steam turbine contains wheel space linked with revolving section having steam bypass pipe. The inlet surface of revolving section is implemented as concentric profiled rings, while the outlet surface is represented as a screen. The inlet and outlet surfaces of revolving section are located so that to form annular channel. By means of the annular channel, the revolving section is connected to the moist steam bleeding chamber. The concentric and profiled rings form additional annular channel between each other. The said additional channel links the revolving section with the moist steam bleeding chamber. During quick turn of the moist steam flow in the area of revolving section, suspended and teardrop-shaped moist precipitates on the rings at high speed. The formed water film moves along the ring surfaces and is removed to the moist steam bleeding chamber though the annular channels together with some amount of steam.

EFFECT: optimally machined and profiled rings together with increased number of annular channels improve effectiveness of moist removal.

1 dwg

FIELD: machine building.

SUBSTANCE: outlet branch pipe (110) of a steam turbine (10) comprises lower outlet branch pipe (105), a steam guide (24), a condenser hole (26), a plate (200) of the outlet branch pipe and an inner channel. The lower outlet branch pipe (105) is connected to the steam turbine (10). The steam guide (24) is mounted in the lower outlet branch pipe (105) and is designed to guide a waste steam flow (35) from the blades (14) of the last stage of the steam turbine (10) casing. The condenser hole (26) is set below the lower outlet branch pipe (105) and is designed to receive the waste steam flow (35) from the above branch pipe (105). The branch pipe plate (200) is mounted in the lower outlet branch pipe (105) and is designed to guide a waste steam flow (35) from the axial direction to the radial one to the condenser hole (26). The inner channel (215) is located in the outlet branch pipe plate (200) and is designed to guide a heat carrier flow inside it as well as to cool and condense the waste steam flow (35) near the plate (200).

EFFECT: improved turbine characteristics due to the condensation in the zone with low velocities near the outlet branch pipe plate (200) providing for reduced boundary layer and improved flow passing through the said branch pipe.

9 cl, 4 dwg

Up!