Westinghouse Electric Corporation

Westinghouse Electric Company LLC

Bruce A Howard

Frank W Cooper, Jr

David A Snyder

Charles D Bice

David J Janocko

Judith E Hodgson

Michael A LaPresti

Nick Tallos

Arnaud Milan

Glenn Quinty

Michael P Skocik

Michael A Lapresti

A controlled leakage, hydrostatic, mechanical seal that eliminates sources of contact friction; advantageously locating contact friction forces to be in alignment with the seal face centroid; optimizes the seal face design to achieve maximum hydrostatic film stiffness and minimum sensitivity to radial taper; eliminating unnecessary O-rings and other sources of significant force variation; utilizes a design-for-manufacture approach to design hardware that can be consistently manufactured to precise tolerances; optimizes the double delta channel seal to achieve adequate compression, minimal frictional drag force, and maximum wear resistance; eliminates sources of circumferential waviness such as bolt preload and other non-axisymmetric features; and, thermally isolates components of different materials to mitigate the deformation due to differential thermal expansion.

Hydrostatic mechanical face seal

A thermally actuated shutdown seal for a rotating shaft having a narrow annular fluid flow path surrounding the shaft. The seal surrounds the shaft with the annulus therebetween during normal operation and constricts against the shaft when the shaft slows or stops rotating. The annulus is maintained open during normal operation by a spacer interposed between opposing ends of a split ring. When the shaft stops rotating, the temperature of the annulus rises, which actuates removal of the spacer from the split ring constricting the split ring against the shaft blocking the annulus. The blocked annulus causes a pressure differential across the seal which urges a polymer seal ring, downstream of the split ring against the shaft which seals the annulus. In one embodiment, the spacer is formed of a meltable material. In a second embodiment, the spacer is removed from the split ring by a thermally responsive actuator.

Thermally activated shutdown seals for rotatable shafts

Apparatus for processing the damaged tubes of a steam generator. This apparatus includes a sleeving tool for inserting sleeves in the tubes, a high-roller tool for rolling the sleeves at their upper ends where they have been expanded, and a low-roller tool for rolling the sleeves at their lower ends in the tube sheet. Each tool is provided with locking pins which engage tubes adjacent to a tube to be processed and suspend the tool in processing position. The sleeves are inserted in the tubes and are rolled by rolls driven by a hydraulic motor. For sleeve insertion and for high and low rolling, the motor is controlled by a servo control valve. The feedback signal to this valve is derived from a flow transducer in the feed line for the motor. The feedback for the force of sleeve insertion is the pressure across the motor derived from pressure transducers in the conductors through which the motor is supplied. For insertion speed and for rolling speed, the feedback is derived from a fluid-flow transducer. The passage of fluid through the servo valve is capable of varying continuously responsive the controlling error signal. The cage or roll tube and mandrel of the low roller are advanced into the sleeve by a piston of a hydraulic cylinder. The flow of fluid to the locking pins and to this hydraulic cylinder is controlled by a directional control valve.

Sleeving of tubes of steam generator

To limit the exposure of personnel to radioactivity within the channel head of a steam generator of a nuclear-reactor plant a cartridge sleeve-blank loader for automatically sleeving a plurality of tubes without the intervention of personnel is provided. The cartridge loader includes a turret or drum which carries a plurality of sleeve blanks around its periphery. A lifter engages the bottom of each sleeve bank in its turn at a sleeve insertion position of the turret and inserts the sleeve blank into a tube. Successive sleeve blanks are indexed to the insertion position for insertion into tubes. The sleeve blanks are slightly bowed or curved so that when a sleeve blank is inserted as a sleeve into a tube, the sleeve, since the tube is linear, exerts a restoring force on the wall of a tube which holds the sleeve in the tube when the lifter is retracted. In inserting the sleeve blank, the lifter moves at a low speed until the leading end of the sleeve enters a tube. Then the speed of insertion is increased. The turret is readily removable from the sleeve loader by use of a unique handle assembly so that any empty turret can be removed in a short time. In the practice of the invention, a loaded cartridge sleeve-blank loader is loaded ready for insertion outside of the channel head. Once all the sleeve blanks on a turret are inserted, an operator enters the manway of the channel head and removes the unloaded turret. The loaded turret is handed to him and he inserts it. The replacing operation can be accomplished by exposing the operator to radiation for no more than about 75 seconds.

Sleeving of tubes of steam generator in hostile environment

Apparatus for processing the damaged tubes of a steam generator either to prepare the tubes for insertion of a sleeve, or to insert a sleeve or to treat the sleeve after it is inserted. This apparatus includes a drilling tool for drilling out plugs, a sleeving tool for inserting sleeves in the tubes, a high-roller tool for rolling the sleeves at their upper ends where they have been expanded, and a low-roller tool for rolling the sleeves at their lower ends in the tube sheet. The sleeves are inserted in the tubes and are rolled by rolls driven by a hydraulic motor. For drilling, for sleeve insertion and for high and low rolling, the motor is controlled by a servo control valve.

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Monroeville, PA, United States of America

Bruce A Howard