Abstract: A method of repairing a turbine rotor wheel having a damaged dovetail includes removing the damaged dovetail from the turbine wheel, leaving a turbine wheel body and welding a ring about the turbine wheel body in place of the removed damaged dovetail. During the welding process, including during preheating, welding or stress relieving, the temperature of the wheel body and ring is differentially controlled to introduce residual stresses in the ring. After welding a dovetail is formed in the ring for receiving turbine bucket dovetails. As a result, the ring has residual compressive stresses in a cold condition of the turbine whereby reduced net stresses in the ring in the location of the new dovetail during hot turbine operating conditions are reduced.

Abstract: A hydraulic tool is operable in an open center (OC) and a closed center (CC) mode and includes a cylinder and a piston within the cylinder. The piston defines a drive chamber and a retract chamber. A valve spool selectively supplies and exhausts hydraulic fluid to and from the drive chamber and the retract chamber. An oil tube is coupled to the valve spool and extends through the piston and is in communication with the retract chamber. The oil tube includes at least one hole that can selectively communicate the drive chamber and the retract chamber. A selector sleeve is provided for switching between the OC and CC modes. In the OC mode when the tool is in the neutral mode, the valve spool is configured to supply the hydraulic fluid through the oil tube to the retract chamber such that movement of the piston can allow communication between the retract chamber and the drive chamber through the at least one hole in the oil tube.

Abstract: A PC board actuator that emulates a muscle fiber includes a first pressure source, a second pressure source lower than the first source, at least one expansion chamber alternately communicating with the first and second pressure sources, first and second valves mounted with the PC board that opens and closes the chamber with respect to the first and second pressure sources, and an actuator member interacting with the expansion chamber to apply a force to the object. The actuator is preferably formed using planar batch technology and the valves preferably comprise electrically controllable flap valves mounted on the PC board. Alternatively, the actuator includes antagonistically arranged expansion chambers that operatively apply reciprocating forces to the object. In other embodiments, the actuator includes plural expansion chambers arranged in series or in parallel in order to increase the overall extent of attainable displacement or to amplify the force generated by the actuator.

Abstract: A rotor assembly for a gas turbine engine includes a bearing assembly that reduces dynamic loads to a support frame and static bending to the rotor assembly during periods of rotor unbalance. The rotor assembly includes a rotor shaft coupled to a fan and supported longitudinally with a plurality of bearing assemblies on a support frame. A number two bearing assembly includes a paired race, a rolling element, and a mounting race. The mounting race includes a spherical face and is secured to the bearing assembly with a retainer that plastically fails at a pre-determined moment load.

Abstract: In a closed circuit moving blade cooled turbine, holes in the radial direction formed in the outer periphery of a second stage wheel are led to cooling air supply holes to second stage moving blades and to prevent the cooling air from leaking into the junction, the holes in the radial direction and the cooling air supply holes are interconnected and the supply members covering the junction are fit into them. The cooling air after cooling the second stage moving blades is introduced into the collection holes formed in the outer periphery of the spacer via the cooling air collection holes and to prevent the cooling air from leaking into the boundary, the cooling air collection holes and collection holes are interconnected and the collection members covering the boundary are fit into them.

Abstract: A turbine nozzle comprises an array of nozzle blades (1) U disposed circumferentially in an annular passage (4) defined between inner and outer rings of a diaphragm and fixed to the inner and outer rings of the turbine diaphragm. The flow passage is defined between a pressure surface (F) and a suction surface (B) of adjacent ones of the nozzle blades, and a cross section of the flow passage includes predetermined ranges extending along a blade height (h) from the inner and outer diameter surfaces (hub and tip end walls) and defined by a curved line, and another range defined by a substantially straight line.

Abstract: A hydraulic actuator for operating a gate valve. The actuator includes a stationary piston coupled to an actuator housing and a moveable cylinder disposed proximate the piston exterior surface. The piston includes a hollow interior portion adapted to house a manual override mechanism. The piston includes a hydraulic pressure line extending between the piston bottom surface and the side of a cap region in the piston. The manual override mechanism includes an override stem disposed within the piston interior portion, the override stem abutting the cylinder.

Abstract: The invention relates to an electromechanical actuating drive for a valve, in particular of a steam turbine. It has a push rod for setting an opening position of the valve and also an electric motor for driving the push rod. The push rod is connected to the electric motor via a transmission device which generates a changing torque, depending on the axial displacement of the push rod. The invention relates, furthermore, to a steam turbine.

Abstract: A crane having an upper works rotatably mounted on a lower works and a boom pivotally mounted on the upper works includes a hydraulic boom hoist cylinder and a hydraulic circuit for controlling the hydraulic boom hoist cylinder. The hydraulic cylinder is pivotally connected to a mast on the upper works and pendently connected to the boom. The boom hoist cylinder preferably comprises two double-acting hydraulic cylinders. The hydraulic circuit includes a closed loop pump and a hydraulic controller connecting the closed loop pump and the double-acting cylinders such that fluid from the pump can be directed either to extend or retract the cylinders, with the hydraulic fluid exiting the cylinders being directed to return to the pump.

Abstract: A valve arrangement including a release valve. The valve arrangement controls a piston of a cylinder assembly upon interruption of a source of fluid pressure supplied to the cylinder assembly, the cylinder assembly including a first port and a second port and slideably housing the piston for movement between an extended position and a retracted position. The valve arrangement includes a valve assembly in fluid communication with the source of fluid pressure and with the first port and the second port to control fluid flow between the source of fluid pressure on the first port and between the source of fluid pressure on the second port, and a release valve fluidly connected to the first port and to the second port, the release valve being operable to control flow of fluid from the first port and from the second port.

Abstract: A variable pitch propeller has a centrifugal lock for blocking blade pitch changes from a normal range of forward pitch angles toward both feathered and reverse positions at rotational speeds greater than a predetermined threshold. The lock mechanism has a pair of stop members rigidly connected to a rack yoke member that has geared engagement with respective propeller blade pinions, and a pair of mass elements that move outwardly in response to centrifugal force to block movement of the lock members outside of the normal range. A pair of springs are connected between the mass elements for biasing them inwardly from paths of the lock members. The yoke is displaced axially by an actuator having an annular hydraulic cylinder. A hydraulic control unit having a motorized leadscrew coupled to another annular hydraulic cylinder is fluid coupled to the actuator, and a simple control circuit provides colored indications of pitch settings.

Abstract: An improved hydrostatic transmission useful as a speed changing device having a single output shaft or a pair of outwardly extending shafts for use, for example, in small vehicles such as lawn and garden tractors. The hydrostatic transmission output may be mechanically coupled to the wheel driving axle by a gear or chain drive, or alternatively may have such means included in the same housing package containing the hydrostatic transmission. When a differential action is needed between the drive wheels of the vehicle, the differential may then also be included in the same housing package. In whichever of such configurations, the hydrostatic transmission comprises a radial piston pump fluidly coupled to a single or twin larger displacement axial piston motor of the swash-plate type by means of a fluid coupling valve supported by the housing.

Abstract: The invention relates to a pressure spring arrangement for brake cylinders, especially of the type installed in commercial vehicles. When using a pressure spring which comprises at least one retracted end, the facing support for the final winding is configured such that when the spring tip of the final winding is applied, a degree of freedom of the deformation exists for the final winding of the pressure spring which exists with a negative angle of incidence, i.e. with an inclination direction contrary to the angle of inclination of the springy windings of the pressure spring. When the final winding of the pressure spring emerges into the adjacent spring winding and during simultaneous deformation along the negative angle of incidence, the pressure spring absorbs additional energy which can be converted into increased spring action during a lifting movement. A roll-off ramp advantageously predetermines the degree of freedom of the deformability of the final winding along a negative angle of incidence.

Abstract: An improved device (10) for moving a load (11) rotationally and/or axially relative to a body (12) broadly comprises: a body; a motor (13) mounted on the body and having an output shaft (14) operatively arranged to move the load rotationally relative to the body; a piston (16) movably mounted on the body and defining therewith a variable volume first chamber (19), the piston being operatively arranged to move the load axially relative to the body; an accumulator (23) charged to a predetermined pressure; a fluid in the first chamber and accumulator; a pump (26) driven by the motor, the pump being operatively arranged to displace fluid from the first chamber to the accumulator; and a valve (28) operatively arranged to selectively permit pressurized fluid in the accumulator to flow into the first chamber to move the piston and load in one direction axially relative to the body.

Abstract: A torque converter comprises an impeller shell, a pump impeller integrally formed with the impeller shell, a turbine runner, a stator, a front cover, and at least one of a flanged portion through which a driving power of an engine is transmitted and a ring gear for a starter. The flanged portion is formed on an outer peripheral portion of an outer hull that includes the impeller shell and the front cover. A pilot boss portion is disposed at an axial portion of the front cover and is adapted to be fitted to a crank shaft of the engine, and a sleeve-like oil pump driving shaft is disposed at an axial portion of the impeller shell and is adapted to drive an oil pump. The pilot boss portion is formed integrally with the front cover through a plastic working operation, and the flanged portion formed at a front portion of the outer periphery of the front cover is increased in thickness through a plastic working operation that forms the flanged portion as a lamination.

Abstract: The invention relates to a process for producing a cooling channel piston, in which the overall height is reduced in that the annular recess has a lower height than the height of the tool used for producing the cooling channel, and the production of the cooling channels starts parallel to the piston boss face, in which the axial height of the annular recess (8) is smaller than the axial height of the cooling channel (13).

Abstract: The interior of a gas turbine moving blade is sectioned by a rib into cooling passage portions. Cooling air enters one of the cooling passage portions and turns to flow into the other cooling passage portion. A stagnation area occurs in an end corner portion of the one cooling passage portion, but a cooling hole is provided so that air flow comes outside of the blade through the cooling hole, and thus cooling air flow occurs thereat. Also, a separation area occurs in a tip end portion of the rib due to separation of air flow, but another cooling hole is provided so that air flow comes outside of the blade and cooling air flow occurs thereat. Further, in a gas turbine moving blade having turbulators provided in multi-stages on a cooling passage inner wall, a film cooling hole structure for eliminating separation of cooling air flow between the turbulators is also provided.

Abstract: A travel motor hydraulic control system for a construction machine having a plurality of hydraulic pumps which supply individually pressurized fluid for a plurality of hydraulic travel motors and a plurality of flow control valves which control the flow rate of the pressurized fluid to be supplied to the motor during an ordinary work. A controller receives a control signal representative of a travel control lever stroke sensed by a position sensor and a control signal detected by a pressure sensor, determines if the vehicle is traveling up a slope, and transmits a command signal to a solenoid operated valve to move a pilot operated shut off valve toward a valve-closing position, thereby the travel hydraulic motors are individually supplied the pressurized fluid from the hydraulic pumps.

Abstract: A turbo molecular pump has a rotor having rotor blades arranged in multiple stages. Each of the rotor blades has a proximal end fixed to the rotor and a distal end. Stator blades are arranged in multiple stages. Each stator blade has a proximal end and a distal end. The rotor blades and the stator blades are alternately arranged in spaced-apart relation in an axial direction so that a spatial clearance between the proximal end of each of the rotor blades and the distal end of an adjacent stator blade is smaller than a spatial clearance between the distal end of each of the rotor blades and the proximal end of the adjacent stator blade. Each of the rotor blades comprises a cantilever member having upper and lower surfaces.

Abstract: A three-position stop type swing actuator has a main piston freely moving in forward and backward directions in an axial direction within a casing, an output shaft placed at a coaxial position with the main piston in such a manner as to be fixed in an axial direction and freely rotate around an axis, a conversion and transmission mechanism converting a forward and backward motion of the main piston into a rotating and swinging motion of the output shaft, and a sub piston having a stroke smaller than that of the main piston a fluid pressure operating force larger than that of the main piston and arranged within the casing in such a manner as to freely move in the forward and backward directions and be capable of being brought into contact with the main piston so as to restrict a middle stop position of the main piston.