Document ad0O4DLbDbJ8grL7g9oD8yMM

FIGHT POWER COSTS tontioued much of the distribution systems, both steam and electrical, are 'charged against the power plant or the process." INVESTMENT COSTS Robinson: "We cannot talk intelli gently about low cost unleu we have sound cost data. The old unit of f/lb/hr of capacity installed has no meaning because you have to guess on the split wherever you have turbine rooms as well as boiler rooms. Here's what we did to get a comparison. We brought together the unit costs of a .number of boilerhouses started up from Nov 1939 to March 1943, see chart, below, to guide us when we wanted to install a 200,000)b-per-hr puJverired-coal-fired boiler at Belle. Column A shows accumulated in vestment in boiler House prior to the new boiler with book values adjusted to the then current construction index of 300. Column B covers the estimated cost of s new boiler, Column J9,-the combi nation of B and C, and Column E, F and G unit costs for other siodlnr commer cial plants, all adjusted tqthe construc tion index of 300. The other two col* iimno, // and /.-.are composite costs; //-of these three plants and ( of seven war plants, built in the some period, and brought.up to l949-195Qcoit* by use of the .construction index, for'that period-- 520. .; ."Table IV. tabulates estimated end actual unit costs far the Chattanooga and May plants built during 1949-1950. Here costs are adjusted to the then cur rent construction index.of 520. Column I gives actual cost of two 40,000-lb-perhr boiled that went in at Chattanooga, Columns.2 and 3,-the estimated end ac tual costs for a third boiler-at this same plant, and Column 4, the average for all three. Columns 5 and 6 cover the May plant installation. Actual cost means final complete design end con struction charges. These 6gures could He plotted directly on the chart, below. You'll note the 1939*1943 plants adjusted to 1949-50 levels would cost $11 or more per lb per hr whereas Chat tanooga is down around ffi/lb/hr, and the May plant less <han|6.5b/lb/hr. "These last two plants are small boiler jobs. The 1939*1943 plonts had boilers of lSO,000-lb*per*hr rating in almost every case. We feel our close adherence to the guides we raentionod above let us best the accepted rule that unit costs for smaller boilers run higher .than for larger ones." . Campbell: "To get belter cost data than the above we set up a classification system where we segregate groups of related equipment. At present the clas* sificatlon covers only Items within the boiler*house structure itself. Table Iff. But it gives sharp comparisons on the relative costs of the major item classes. For example, Plants D and H have the highest steam-generator cost but the lowest building. Both, as you'd expect, are in the South with much of the equip ment outdoors; Piping in Plant f runs very low. The reason Is simple. It's a small oil-burning plant with a relatively short distribution system. "fn Table HI, siaam generator means boiler, furnace, fuel-burning equipment with accessories attached or considered a part of these facilities, plus draft and dust-collecting equipment. Foundations, supports, drives, and other direct auxil iaries are included unless Yj listed (n other categories. "Boilers prove the largest in this classification. So thing possible to hold their .tg, costs down. In the first place, boilers offer the most iramed^ ings. Then wo study. iumhur 2? ter peaks so we can lotd alH^ during the winter and yet jj',y boiler of! the line during the so each boiler can receive tn aiilgj speetion and overhaul. .'to "As steam demands inereiK sought woys of removing beil^ bottlenecks. In one ease with-^| turer cooperation we upped the&L by 10% with only minor ehang a rule we never buy boiler, capitf excess of indicated loads. We a boiler designed to receive supi era, hut they'll never go in until' heated steam seems a definite *-2 advantage. The same thing auxiliaries. We buy to meet'iffi conditions only, unless future *~ in pressure or temperature are: possibilities. "Packaged boilers carry a itr^ peal. They can- be easily reoatejl' used elsewhere as their originift outgrows them. "Fuels are olwaya a prime coni tion. In addition to the usostj {Continued on page 206)$! III. Percent Breakdown of Major Elements in Power Flui Ho. Soften, Si 40,000 t< to.oao ti 10,090 1 41,000 ii toAoe (I 1,000 Ii 00,000 4t 110,000 CMt CmT C*t C*d fud Swn* Peatfiid wd Site* sn*e IV. Low Economical Power Investment. DollarsAb/Hr f**l h4lt Owl m4 oti tiMdSwe Pn44v Ptatwa Ekctrf* J--<9,000 Actoaf ITS 1.19 .9* .T9 Chattanooga ,------ P--49,000--H filJawtid 4cfwI COMPARISON of costs for 1949*1950 vs 1939*1943 shows benefit of planning hUlil MMUmmi Total Ml DMribWtvo lotel 1.SO -- -- -- 9.09 .99 -- -- -- 7.11 10) ENGINEERING AND MANAGEMENT SECTION DATA SHEET. Approximate Length of V-Belts Here's a chart to figure the length of V-belt needed for given conditions. <11 Find center distance between sheaves on-left-band seals. (2) Find pilch diameter of small sheave on right-hand scale. (3) Lay a straight edge on these two points. Where It euts the vertical speed ratio scale, read the length of belt on center scale. Example: Connect 44-In. center distance, on left, with 6-in. pitch dia of small sheave, on right, with straight line. Whete It Intersects with 6.25 speed ratio read 160-In. belt length. 5 6 7 6 9 10 Coartaj, AUU-Cholmtn Manufacturing Co ENOINEERINO AND MANAGEMENT SECTION o power 703