Abstract: A steam turbine having improved stationary parts in which a moisture removal slot is formed in a blade ring cylinder immediately upstream of the last row of rotating blades. The slot has a reduced width inlet throat portion and an enlarged manifold portion. The manifold portion of the slot distributes the moisture collected to a plurality of radially oriented discharge holes formed in the blade ring. The inlet throat serves to insolate the manifold from the swirling steam flowing through the turbine, thereby preventing entrainment of the moisture droplets into the steam flow. The blade ring encircles the tips of the last row of rotating blades and the outer flow guide is integrally formed on the blade ring. The steam turbine also has a new inner flow guide that matches a new last row of rotating blades. The new inner flow guide is attached to the existing inner flow guide by welds.

Abstract: A steam turbine having improved stationary parts in which a moisture removal slot is formed in a blade ring cylinder immediately upstream of the last row of rotating blades. The slot has a reduced width inlet throat portion and an enlarged manifold portion. The manifold portion of the slot distributes the moisture collected to a plurality of radially oriented discharge holes formed in the blade ring. The inlet throat serves to insolate the manifold from the swirling steam flowing through the turbine, thereby preventing entrainment of the moisture droplets into the steam flow. The blade ring encircles the tips of the last row of rotating blades and the outer flow guide is integrally formed on the blade ring. The steam turbine also has a new inner flow guide that matches a new last row of rotating blades. The new inner flow guide is attached to the existing inner flow guide by welds.

Abstract: A steam turbine having improved stationary parts in which a moisture removal slot is formed in a blade ring cylinder immediately upstream of the last row of rotating blades. The slot has a reduced width inlet throat portion and an enlarged manifold portion. The manifold portion of the slot distributes the moisture collected to a plurality of radially oriented discharge holes formed in the blade ring. The inlet throat serves to insolate the manifold from the swirling steam flowing through the turbine, thereby preventing entrainment of the moisture droplets into the steam flow. The blade ring encircles the tips of the last row of rotating blades and the outer flow guide is integrally formed on the blade ring. The steam turbine also has a new inner flow guide that matches a new last row of rotating blades. The new inner flow guide is attached to the existing inner flow guide by welds.

Abstract: A pressure relief diaphragm is associated with a turbine housing and is operable to relieve excessive pressure within the turbine housing to prevent damage to turbine blades. The pressure relief diaphragm includes a safety housing having a mounting flange thereon arranged to mate with a turbine flange so that the safety housing is positioned over a relief opening in the turbine housing. A first solid, frangible solid disc covers the relief opening in the turbine housing and has a peripheral portion interposed between the mounting flange on the safety housing and the turbine flange. A second solid disc is positioned in the relief opening in the turbine flange in abutting contact with the first solid disc. A first plurality of bolts secures the mounting flange on the safety housing to the turbine flange. Spring washers associated with the first plurality of bolts maintain the positional relationship between the safety housing and the turbine flange.

Abstract: Apparatus is provided for increasing the bending flexibility of the horizontal joint flange of a low pressure steam turbine. The radial width of the horizontal joint flange in the support area where the turbine inner cylinder rests on the outer cylinder has been significantly reduced. In order to accommodate a reduction in the radial width of the flange in this area, the present invention provides a novel arrangement of the functional features of the cylinder support area. In a preferred embodiment the horizontal joint flange is capable of being narrowed in the radial direction due to the strategic rearrangement of the functional components in the support area. The present invention also provides retrofit steps for modifying existing turbines in order to provide the features and benefits of the improved apparatus.

Abstract: A thermal shield for a steam turbine inner cylinder surrounding a plurality of turbine blade stages and having an outer cylinder substantially enclosing the inner cylinder. A steam inlet is connected to the inner cylinder through an outer cylinder for admitting high temperature steam into the inner cylinder to effect rotation of the turbine blade stages and a steam exit emits cooled steam from the inner cylinder into a space between the inner and outer cylinders. The shield reduces thermal stress on the inner cylinder from contact on an inner surface with the high temperature steam and contact on an outer surface with the cooled steam. The thermal shield is attached to the outer surface of the inner cylinder and spaced therefrom by a predetermined spacing. The thermal shield extends about all surfaces of the inner cylinder and forms a substantially closed inner space between the shield and the inner cylinder to prevent the flow of the cooled steam over the outer surface of the inner cylinder.

Abstract: A detachable apparatus is provided which facilitates rotation and handling of an alignment dowel during its installation into a steam turbine cylinder. The apparatus consists of a body having a threaded portion and a handle. The threaded portion allows the apparatus to be attached to the dowel prior to assembly. An elongated nut is threaded onto the body of the apparatus and, after being tightened down against the dowel, locks the apparatus onto the dowel. The dowel can be rotated in the cylinder by applying torque to the handle of the apparatus or by engaging a wrench onto the elongated nut.

Abstract: Improved methods and apparatus for retrofitting longer last row rotational blade assemblies in steam turbines are disclosed. The apparatus of the present invention permits the exhaust flow guide to be mounted directly to modified last row stationary turbine blades. In a preferred embodiment, the outer blade ring of the last row of stationary blades in a steam turbine is modified by machining two grooves which permit a modified blade assembly outer ring and integral blade ring extension to be mounted in the turbine. The extension section is configured to accept connecting means, such as bolts, which permit the direct attachment of an exhaust flow guide to the modified outer blade ring at each end of the turbine. The present invention simplifies the attachment of such flow guides and can improve the harmonic characteristics of the turbine by lowering the natural frequency of the assembly and include the mass of the flow guide in the mass of the stationary blade assemblies.

Abstract: Integral cast inlet ring sections for low pressure steam turbines are disclosed. Preferably, semicircular inlet ring sections from opposing sides of the steam inlet are joined together by integral staybars to form an inlet ring subassembly. After fabrication into a turbine inner cylinder, the two inlet ring subassemblies are preferably joined by a horizontal joint, such as a bolted connection, to form a circular inlet ring. The present invention eliminates welds and other connections typically associated with staybars and thereby eliminates a source of stress concentration and fatigue failures in steam turbines. The present invention also permits the inlet ring to be welded to a flange in a manner which eliminates potential delamination of the flange by fusing the sites of potential delamination.

Abstract: A steam turbine is disclosed which eliminates the transfer of thermal deformation from the inner cylinder to the stationary blade assemblies. A dual plane bolted connection and a free floating tongue and groove interface formed between the outer ring of the stationary blade assemblies and the turbine inner cylinder provided the clearance necessary to remove the deformation associated with the stationary blade assemblies, while supporting them within the turbine assembly. The outer ring of the stationary blade assemblies may either be formed as an integral component of formed from two sections which are then welded together. The present invention also permits the rotational blades of the turbine to be placed in close proximity to the outer ring of the stationary blade assemblies and the positioning of the flow guide on the outer ring, since the deformations due to the thermal deformation of the inner cylinder are now isolated and the deformation due to the stationary blade assemblies is eliminated.

Abstract: A fully-floating inlet flow guide for a double-flow steam turbine includes a pair of partially overlapping, generally cylindrical sealing rings circumscribing a turbine rotor adjacent a steam inlet with each of the bands being coupled to a respective one of a pair of first stage nozzle rings positioned on opposite sides of the inlet for directing steam into an axial flow path. The rings are provided with an annular seal at their overlapping portions such that axial expansion and contraction is accommodated without steam leakage through the seal. Radial expansion and contraction of the sealing rings is accommodated by attachment of each ring to a respective nozzle using a circumferential groove in a radially inner surface of each nozzle ring diaphragm and a tongue on each of the rings which fits into a respective groove. Each tongue has a plurality of circumferentially spaced slots and a block slidingly positioned in each of the slots.

Abstract: In a steam turbine having a first turbine element adapted to receive a flow of steam for operating at a first predetermined pressure, the first turbine element including an exhaust protion, a second turbine element adapted to receive the flow of steam for operating at a second predetermined pressure that is relatively lower than the first predetermined pressure, the second turbine element including an inlet portion, a method and apparatus for connecting the inlet portion to the exhaust portion by crossover piping which includes a pair of vaneless turning subsections each of which have a substantially long radius of curvature.

Abstract: A steam turbine including a casing structure which has an outer cylinder and the inner cylinder, a blade support ring, a plurality of stationary blades arranged in a number of annularly-shaped rows along the length of the turbine on the ring, and a rotor with a plurality of rotating blades arranged in a number of annularly-shaped rows along the length thereof and attached thereto, also includes improved structure providing integrated casing alignment and steam extraction. The improved structure, in combination with the conventional extraction steam piping that exits from the inner cylinder, includes a load plate arranged perpendicularly to the extraction steam piping, one or more flex plates attached between the load plate and the inner cylinder, a plurality of alignment lugs attached in predetermined positions about the load plate, and a plurality of stiffening gussets attached both to the alignment lugs and the load plate.

Abstract: A steam turbine has an outer blade ring supporting a row of stationary blades and an adjacent downstream row of long rotatable blades. The outer blade ring has a generally conical flow-guiding surface for outwardly guiding the steam as it flows through the row of stationary blades. The outer blade ring is supported by a radially juxtaposed carrier ring having a flow-guiding surface axially adjacent to and extending outwardly from the flow-guiding surface of the outer blade ring. A spacer ring is axially adjacent to the carrier ring and has a flow-guiding surface adjacent to and extending outwardly from the flow-guiding surface of the carrier ring. An exhaust flowguide is axially adjacent the spacer ring and radially adjacent the row of rotatable blades for guiding the steam from the rotatable blades.

Abstract: A steam turbine having a seal, connected between the annular rows of stationary blades positioned proximate the turbine inlet, for preventing the circumvention of the flow of steam from the desired flow path and for preventing the transfer of thermal loads between the rows of stationary blades. The seal includes a band connected to one of the stationary annular row of blades and extending across the inlet, a support piece connected to the other stationary annular row of blades, and a resilient seal connected to the support piece and positioned to be in frictional engagement with the band.

Abstract: In a nuclear or fossil steam turbine, a novel arrangement of structural elements is utilized to support a stationary blade ring, that is normally supported on a radial wall of a turbine inner casing, on an upstream separate blade ring. Thus, the stationary blade ring is separated from undesirable thermal deformations that naturally occur in turbine inner casing structures. A downstream stationary blade ring is fit to the upstream separate blade ring to maintain its relative position, and is attached using connection bolting and alignment pins or dowels. The inventive system is compact, low cost, and reduces bladepath seal leakage, leading to improved heat rate.

Abstract: The inlet flow guide includes a generally cylindrical shroud plate, a generally cylindrical bridge piece, elongated attachment members, biasing members and sealing members. The shroud plate is in confronting cylindrical sections, is adapted to be attached to the pair of confronting stationary blades of the annular rows of turbine blades, and includes tapped bores therethrough. The cylindrical sections of the shroud plate are in arc cylindrical sections. The bridge piece is in semi cylindrical sections and has bores therethrough of a predetermined size to accommodate expected movements during the operation of the turbine, and which are capable of alignment with the bores of the shroud plate. The attachment members have enlarged heads and shoulders and are disposed within the bores of the bridge piece and shroud plate to attach the bridge piece to the shroud plate.

Abstract: A steam turbine having a chamber in the inlet end thereof adjacent the thrust balance piston and dummy ring formed so that the temperature is substantially reduced while the pressure is only slightly reduced to optimize the pressure temperature affect on the balance piston and rotor utilizing labyrinth seals and a static seal together with vent ports in fluid communication with the chamber and an area downstream of the first row of rotatable blades to provide a more efficient and reliable turbine.