Document B5ED23J1q9179vVzQ5w47ZOKm

THE STUDIES continued octor sphere outride the cylinder, and in the dump end makeup tanka. Shielding. Reinforced limestone- aggregate concrete, S ft thiek, shields the reactor, see sketch p 102. Steel plates line the inner and outer surfaces of the shield. The vertical fuel-elementcharging and control-rod tubes and the horuontal water-discharge pipes lead* ing from these tubes to the header* form a large part of the top shield. Shielding around steam generators, piping, pumps and miscellaneous stor age tanks consists of 3-ft-thick con crete floors, walls and ceilings. Steam generators and pumps stand in indi vidual cells reached through plug-type trap doors. Turbines, turbine piping end auxiliaries stand in open, un shielded areos accessible for'normal maintenance. To moke repairs on a unit of equip-' ment, motor-operated shutoff volves first isolate it from the heavy-woter system. The activated heavy water in the unit then drains to a shielded stor age tank. Light woter flushes out the unit until radioactivity falls to o level safe for men to enter the cell and per form the necessary repair work. Reactor Control. Amount of heavy water flowing from the reactor ond Its temperature ot each fuel-tube outlet ond control-rod opening are monitored. Manually operated valves on each tube adjust flow distribution over the re actor lattice area. Adjustments are mode on the basis of two thermo couple readings at each tube outlet. A rapid-scanning device for pressures and temperatures helps localise defects as they develop. The scanning equip ment automatically shuts down the reactor when certain limits are ex ceeded. Failure of both thermocouples on any tube shute dawn the reactor. Defective flow detectors are considered a serious hosard. Several thermocouples in the hottest area of the reactor measure and record the uranium-metal temperature. Safety rods dropping Into place au tomatically shut down the reactor on: (1) loss of sphere pressure (2) exces sive reactor power (3) short reactor period (4) fuel-element failure (S) serious heavy-water leak (6) steamgenerator failure (7) excessive radio activity in reactor building. Control rods of 1.5%-boron steel are clad with stainless steel to resist cor rosion. Guide tubes prevent the rods jamming in the tube sheets or shifting their position by flow of the coolant Coolant flow dissipates heat generated in the rods. Piping. To minimise the amount of coolont holdup in the piping, a flow velocity of 2S ft per see was chosen, 1H and the length of piping was held to a minimum by arranging the steam gen erators in o tight circle around the re actor as shown at top of p 102. Angle heoders, taking the heavy water from the 211 individual fuel etements and control-rod headers, con. neet to a ring heoder 21 ft in radius circumscribing the reactor. This heod er feeds the 18 individual 12-in. heod ers connected to the top of the steamgenerator coolant boxes. The 12-In. outlet connections, from a pair of steam generators, join an 18-In. suc tion line to one of the nine coolantcirculating pumps. The pumps' dis charge headers, 18 in. dla, conned to the reactor ot equally spaced intervals around the reactor shell. Steam Generators. Each of the 18 units produce 180,000 lb per hr of 180psig saturated steam. These are ar ranged in pairs to reduee the number of coolant pumps and valves. Each unit hat an 88-in.-dio shell, 24 ft long. The 656 U-tubes hove a total heattransfer surface of 3975 sq ft. The cool, ont enters and leaves at the same end from a single box with o horisontal division wall to separate Inlet and out let compartments. By using o double tube sheet, one serves as an end plate for the steam and water shell and the other as the plate of the coolant box. This avoids leakage of the coolant into the Ifghtwater system and simplifies detection of tube-roll leakage. A subcooling sec tion uses incoming feedwater to subcool the leaving coolant. Coolont-elrculotlng pumps pre sented one of the major design prob lems of the plant. This arose from the combination of the large flows to be handled, the high suction pressure to be sealed, the essentially low gland leakoge, the high liquid temperature and the coolant radioactivity. The pumps are single-stage overhanging-impeller design with the one gland exposed to suction pressure. To ovoid flashing In the gland, coolant at 100 P enters an intermediote point of the gland. The teal coolant flows along the shaft through labryrinthine packing into the pump In one direction and into an annulus in the apposite direction. About 5 to 10 gpm of seal coolant Is needed. The small external leakage drains back to the makeup tank. Oland-teal coolant comes from each pump discharge, passing through a small heot exchanger before entering the gland. One of the three pumps for each main unit is steam-turbine-driven, the other two are driven by 2000-hp electric motors through hydraulic couplings. The couplings assist in con. REPORT ON ATOMIC ENERGY trolling plant output on load variation. Turblna-Oonorotors. Three 80,000- kw units supplied by the reoctor con generate a total of 254,000 lew with l-in.-Hg abs backpressure, at a heat' rate of 14,111 Btu per kwhr. Net steam available for main turbines will gen erate 246,100 kw. Electrical auxiliaries will use 14,000 kw, leaving a net out put of 232,100 kw. At 2.5-in-Hg back- L pressure the net drops to 2U.500 kw. <' The tandem-compound double-flow turbines have 35-in. lost-stage buckets. 'y Since the turbines use saturated steam f they have two moisture-extraction lo cations. One uses notches In the lead- V Ing edge ol the buckets to throw the [> moisture to an annulus in the easing, where it is carried out of the turbine : by 1% extraction of steam. This re- !* duces moisture from 7.4 to 6%. f The other consists of a series of corrugoted plates in the large crossover, i The plates separate the moisture and ? carry it to o drain, reducing steam moisture content from 10.6 to 6.6%. ' Because of the low steam pressure and the nonextraction cycle used, the surface condensers become very lorge. To attain l-in.-Hg backpressure there f. must be 130,000 sq ft of surfoce. Four 'jg| 35,000-sq-ft units per turbine seem to `[I be the best arrangement Makeup water '/Vj for the plant comes from a demineral- :> Ixer since bled or exhaust steam is not t'V available for evaporators. Jjfi Costs. Table U shows the estimated ,41 investment for the 240,000-kw in- Jl tailed-capacity plant Tbe total of (118.000,000 represents (492 per kw. | If the reactor was designed for light- r, water cooling ond moderation, which f would require enriehed fuel, the initial I investment could be reduced by about *J. (47,000.000. Cost per kw would drop !from (492 to (297. These cost figures assume that fabricated fuel elements '! are furnished ,by others. Cost of the initial fuel charge has not been in- / eluded. Conclusions. Considering present ) status of reactor technology, it Is felt . that the heavy-water-reactor concept has the best economic possibilities, tin- N certainties are availability and cost of heavy water, practicality and cost of chemical plants to process the fuel elements. The gas-cooled reactor could pro- 's' vide a substantial beginning in otomie power with minimum interference with . * production reactors now under con struction or contemplated. Puel ele ments should be lets costly than some of those used in production reactors, they can be processed in existing i } plants. Both reactor designs are feas- ,*j ible from engineering end operating standpoints. ^ sown ; Powers DATA SHEET Typical Cable Applications in Generating Stations Sem'co pus ms, iyc* Ala* J.pA wo/loga hw/lotian 2,000 Hcel-rciUtont rubber (RH) 13,000 Oionc-rerittonl robber* 17.000 Vomithod-cambric AUXILIARY MOTORS *7.000 2,000 Impfcgaotad paper Hcat-rcdtlant rubber ((H) 15.000 17,009 '600 3,000 Vomhhed-cambric Vinyl raiin Aibaitos-ranrithad-combric CONTROL CARLES 600 Hcat-rasiilanl rubber 600 OtatM-retletoM rubber 600 Vinyl rosin, polyethylene fnttol/otioa Conduit' tniutotars Ducts* Conduit, ducts Condole Ducts* Conduit, ducts Conduit* Insulators Ducts' Any Centring Cotton braid Cotton braid Neoprene locket Lend chcotb Cotton braid Neooreno jacket Load tboolh Cotton braid* Cotton braid Load shootb* Lood shootb Candait* Conduit, ducts Ovett* Conduit, ducts Conduit* Ducts* Conduit' Duch' Conduit Conduit* Conduit* Dwelt* Cotton braid* Neooreno jacket Load shootb'* Neopreno jacket Cotton braid* Lead shootb*, '* ` Cotton braid Lood shootb Nona Cotton braid* Asbestos brold* Lood shootb** Conduit* Conduit, duett* Duett* Conduit* Conduit, ducts* Duch* Conduit, ducts Cotton braid Load ibootb** Neoprene jockel Cotton braid Load shootb** Neoprene jocket Vinyl ratio Fl/iltk Note 3 Note 3 None Note S Nora 3 Nona Note 5 Noto 8 Note 8 Noto 5 Note S Not# 3 None Nora 5 Nona Noto 3 Noto S Note 8 Note 5 None Note 8 H P*," Note 5 Note 3 Note 3 None Note 3 Note 3 None None EXCITER AND FlltO UADI1 IS,000 Otooe-reeUtonl rubber 17,000 Vamitbad-combric Conduit, ducts Conduit, ducts Coadult, ducts Conduit, duett Lead sheath** Neoprene locket Cotton braid Lood shootb** Noto 5 Nano Noto 3 Note 3 RHEOSTATS 300 All etbeitai foceplata to resistors Aibaitos braid HF" SOILER ROOMS, ASHPITS 5,000 Atboftes-ramiihad-combric 5,000 2,000 Varniihad-combric Heot-rosiifant rubber ((HI Conduit* Conduit Ducts* Conduit* Ducts* Conduit* Ducts* Conduit, ducts Cotton braid* Asbestos braid* Lood sboolb Cotton braid* Lood shootb Cotton braid* Lood shootb Ntoproao jocket HF* Noto S Noto 6 Noto J Noto 8 Noto S Nona POWER TRANSFORMERS Primary and Mcandory earvkoe 2.000 Heot-reehtoal rubber ((H) Conduit Ducts' Conduit, ducts Lood shootb Noepreno jocket Painttitled Note S Nona 8,000 Oioao-rciistont rubber* Conduit Ducts* Conduit, duets Asbestos braid Lood sbeath Noepreno jacket Pointfilled Noto 5 Non# 17,000 Vaiaiihod cambric Conduit Ducts* Cotton braid Leod shooth Noto 8 Nora 5 132,000 Impregnated paper Conduit, ducts Lood shootb Noto 5 I--owelty wilautafctf. l--etuatfally dm mait ceetlOer Adi '**4*MIS Mock. 4--ait bcstlMi. S--NcopccM keea-type )ockt #nrull to ffMictlu eoo!"** cormlon aad alacrralritt. *--pratarably ikltldtO 2 k*. T--Jaak up ihlctfUf racaamtaiSallaat. S-cwaal* block ar to taithj patal-ti<U4 ond flnUkiO tar ladaar vart. --latertackiO Heel Ofow amratl far Metallic PO" caattrvclUaj altarsata t braaia tar ilagla ceaOuctar a* tar carroths cmOJUms. tO-ottamola of Ind Owol*. fkbravi catering oad latartackad amor tar poo caouractlaa. II--Orel-, Home, sod moiitara-raeittaat. II--la kalta* tacalWi. M--I* am rallablllta- Coortosy f Aims, Ffocfrtcof fnpfneer, Anaconda Win 8 Cablo Co fuir mj POWER 103