Westinghouse Electric Corporation

Donald G Lorentz

Robert Draper

Allen J Baum

George C Economy

A model steam generator including an improved feedwater system for monitoring the conditions of the heat exchange tubes within a nuclear steam generator is disclosed herein. The feedwater system generally comprises a first conduit fluidly connected between the boiler vessel of the model steam generator and the feedwater of the nuclear steam generator via a first valve, and a second conduit which is fluidly connected between this boiler vessel and a feedwater reservoir by way of a second valve. The feedwater reservoir is in turn connected to a source of demineralized, deaerated water by means of a third conduit having a third valve. This reservoir is further fluidly connected to the feedwater of the nuclear steam generator by means of a fourth conduit having a fourth valve. The improved feedwater system of the invention gives the operator three running options. First, he may run the model steam generator directly off the feedwater used in the nuclear steam generator. Second, he may fill the reservoir with feedwater used in the nuclear steam generator and mix anti-corrosive or cleaning additives into this feedwater before introducing it into the model steam generator in order to test their efficacy. Finally, if anti-corrosive or cleaning additives are already in use in the nuclear steam generator, he may fill the reservoir with demineralized, deaerated water and test alternative additives. The improved feedwater system also includes a means for maintaining a turbulent flow through the feedwater inlet conduit so that particulate contaminants in the feedwater will not have an opportunity to settle out before the feedwater is introduced into the model steam generator.

Model steam generator having an improved feedwater system

An improved, compact model steam generator having multiple primary systems is described herein. The model steam generator of the invention is capable of simultaneously simulating a plurality of thermo-hydraulic conditions which may exist in various areas of a full-scale nuclear steam generator in order that the effect of these various conditions on the heat exchange tubes within the full-scale generator may be separately monitored. The model steam generator of the invention generally includes a boiler vessel having a primary side which houses a plurality of individually controllable primary systems, a tubesheet, a secondary side, and a plurality of sample heat exchange tubes for transferring heat between each of the individual primary systems and the secondary side of the boiler vessel. A heat flux control system connected to each of the heat sources within the primary systems allows the operator to separately adjust the heat fluxes of each of the ends of the sample tubes disposed within the secondary side of the boiler vessel. In order to reduce the longitudinal and diametrical dimensions of the primary side of the boiler vessel, the heat source used in each of the individual primary systems is preferably a single, high-intensity electrical heater formed from a coil or other high density configuration of electrical resistance wire. Moreover, each of these primary systems may be housed within the tube-receiving bores of the tube sheet of the boiler vessel in order to minimize the longitudinal dimensions of the primary side even further.

Compact model steam generator having multiple primaries

A model steam generator including a system for facilitating the inspection of the sample tubes within the boiler vessel of the model generator is disclosed herein. The system includes means for detachably connecting the tubesheet from the primary and secondary sides of the boiler vessel. In the preferred embodiment, both end of the tubesheet and the abutting ends of the primary and secondary sides of the boiler vessel are circumscribed by tapered flanges. The tubesheet is detachably connected from the primary and secondary sides of the boiler vessel by means of Grayloc.RTM.-type annular clamps which are circumscribed by grooves for receiving the abutting flanges at the tubesheet joints. Additionally, the system includes a frame for suspending the secondary side of the boiler vessel, a wheeled cart having a jack for both laterally and vertically moving the primary side of the boiler vessel and the tubesheet into a clamping position onto the secondary side of the boiler vessel. The system further includes a set of threaded guide rods and sleeves for properly aligning the primary side and tubesheet with the secondary side of the generator. The detachably connectable Grayloc.RTM.-type joints between the tubesheet and the primary and secondary sides of the boiler vessel, in combination with the cart and screw jack, afford a convenient means of disassembling the boiler vessel and inspecting the sample heat exchange tubes within the model steam generator.

Model steam generator having means to facilitate inspection of sample

An improved process for removing oxygen from an aqueous medium used in a steam generating system, the aqueous medium having hydrazine added thereto, wherein hydrazine-containing aqueous medium condensate formed in a condenser is exposed to ultraviolet light in the condenser hotwell, prior to being recycled to the steam generator. The exposure to ultraviolet light is for a period of time sufficient to effect removal of the dissolved oxygen by the hydrazine without the need to add chemical additives or catalysts to the system.

Growing community of inventors

Irwin, PA, United States of America

Donald G Lorentz