Abstract: In a spray nozzle, a carrier defines a spray aperture, a groove surrounding the spray aperture for receiving an o-ring, a first locating bore for slidably receiving an orifice plate seated against the o-ring and for aligning the orifice plate with the spray aperture, and a second locating bore for slidably receiving a swirl unit and aligning the swirl unit with the orifice plate and spray aperture. A pair of retaining lugs project inwardly from the carrier a predetermined distance for engaging the upstream end of the swirl unit to thereby retain the swirl unit and orifice plate within the carrier. The swirl unit defines on its peripheral surface a recessed flat which is aligned with the retaining lugs to thereby clear the lugs upon inserting the swirl unit into the carrier. An elongated slot is formed on the upstream end of the swirl unit for receiving a screw driver.

Abstract: In order to reduce the time and difficulty of disassembling a seal arrangement in a cramped radioactive environment, a nozzle assembly hub is provided with a step bore which receives a seal arrangement, a compression collar, and a retaining nut which presses the seal arrangement into engagement with an inner wall portion of the hub and an outer wall portion of an ICI (in-core instrument) seal plug assembly. The ICI units remain connected to the seal plug assembly during normal disassembly operations. In this manner, the nozzle assembly may be disassembled by merely removing the retaining nut, compression collar, and seal arrangement and lifting the reactor head, along with the nozzle assembly, over the ICI units. The compression collar extends outside the retaining nut such that the collar can be engaged and compressed by an hydraulic loading tool while threading the retaining nut onto the hub.

Abstract: In order to reduce the time and difficulty of disassembling a seal arrangement which includes a Grayloc flange, in a cramped radioactive environment, the Grayloc hub is modified to include a step bore which receives a seal arrangement and a retaining nut which presses the seal into engagement with an inner wall portion of the hub and outer wall portion of an ICI (in core instrument) supporting column. A loading ring is threaded onto a portion of the column. Bolts associated with the ring are screwed down onto a belleville washer which is disposed between the loading ring and the top of the retaining nut for maintaining a desired amount of load on the seals irrespective of thermal variations.