Document 8L1Vj910JMNKZNRba6Q8n7yy

CONTROL ACTIONS: Proportional Action Poet Action Rata Action Anticipatory Action from ekangn in ...combuttion rate CONTROLLING QUANTITY OR FUNCTIONS: Superheat Temperature Reheat Temperature Sum or Difference of Superheat anti Reheat Temperature EQUIPMENT ACTUATED: DeiuperhetUing vaUxt Hy-peti dampen Tilting human Goa recircutoiion dampen Proportioning dampen O Condenter velvet THIS ELECTRONIC CONTROLLER HAS THE TO HANDLE TOUR SUPERHEAT-REHEAT CONTROL PROBLEMS Horo Is a controller which look* at superheat temperature, reheat temperature or any of their combinations--electronically "computes" the proper control action--and applies it to the correct actuator or group of actuators. This flexibility of control is vitally important in regulating today's critical superheat-reheat temperatures. Your boiler may employ dampers, tilting burners or valves, separately or in combina tions, each having its individual control charac teristics. In many steam generators a single actuator affects both superheat and reheat tem peratures over part of the load range. As load and fumaco conditions require the 'control to regulate different actuators or groups of actuators, the control actions os well os the controlling quantity or function--superheat, reheat, or the Bum or difference of these temperatures--must be varied accordingly. The built-in electronic intelligence of the LAN Series 'SO Controller enables it to consider all these variables simultaneously. This controller has been supplied with as many as four separate groups of control actions--proportional, reset, rate and anticipatory--to meet individual control needs. Inherent self-balancing permits rapid automatic transfer from one actuator to another, while intro ducing a completely new set of control actions, as well as a different control quantity or function. Inherent flexibility of the Series '50 Controller allows the complete superheat-reheat control system to guard against interaction of the two steam temperature controls and to provide the close temperature regulation your boiler requires. If you're thinking of tomorrow's--as well as today's--superheat-roheat control problems, why not look to LAN--the only instrument company offering integrated controls for both steam and electrical generation. Write Leeds A Northrop. Co., 4910 Stcnton Avenue, Philadelphia 44, Pa. LEEDS NORTHRUP Imul MMwJtMWrWi , /urmmcei Corner 1 933 VOLUME 97 NUMBER 11 W ENGINEERING AND MANAGEMENT gpier-fsed pump* for luperpreisure plonli- 71 Haven thrives with more diesels 75 jjjoiv-jb pick Iho most economical pipe insulation--------- ___ 78. ^Fety, reliability, economy:-watchwords for topnotch station-- 82 [tfwflgb engineering--on oid to instrument and control design . []> to use system-head curves in pump choice, application. fjyti/azinei New oid to woter treolment___________________ 'steal mills fight their pollution problems-----------------------------fr*a*c-'tion tower moves il.ot.or_ ,j$ta Sheet: Superheat compensates for steam-lino lostei- 91 94 PLANT OPERATION AND MAINTENANCE graining operators to take over a new plant---------------------------- . 103 tei'rlmpBCt and overhaul your steam turbine now-----------------^Oual-fuel-engine maintenance------------------------------------------------'tvr More on variable-displacement pumps 106 114 116 tjp;belh do a lop job even on those spociol drives 118 ^Check-out" ydur new refrigeration system -- -- 120- Hve shop-designed and shop-made sofety gadgets , . 122 Procticol ideas ------------- -----124 Argumenfcorner^ . 138 `Plant problems- . 130 . 140 . 136 Mormoduke Surfaeeblow_ 142 % READER SERVICE SECTION [Speaking of power 146 New froe bulletin* 163 ^fPowrr newi _ 148 Goorgo Edward* 166 <',?'Technol briefs---- 130 My biggest boner__________ 226 "rh - .VHont-equIpmenf news. 154 Englnoer* bookshelf 228 TURBINE OVERHAUL, like many another key mainienasce operation, is often dis cussed but rarely pictured. Thai's why Associate Editor Sieve Elonka was ao plcaaed when he was able to enlist the co operation of John Wolf, chief engineer ot F 1> M S*hrfer Brewing Co, for photo record of a job on one ol (heir turbines. Chris Crube, McGraw-Hill photographer, did the "shooting," with John N*hsum, first assistant enginter, helping hint get the phoioe ho wealed. The result of tome pretty strenuous oe. tivity by all concerned appears on the rover snd in the article beginning on p 106. There you ice key pictures from the many actually taken, arranged in meaningful sequence with pithy captions--all for the purpose of telling you more about e turbine overhaul than words atone could ever tell Next month .. * Fuel handling and storage appear deceptively simple. There's no complex theory, but for good results you need plenty ol judgment in-selecting a system from among the many possible arrange ments of a vost array of equipment designs. To make this job easier is the aim of our December "special," * This handbook outlines clearly the basic functions of handling and storage, rounds up for you the tools of the job. It covers fuel oil and gas as well os coal and oilier solid fuels. * Header reports show top interest In Haul Brindisi's June article on water treatment for packaged fireiube boilers. So you'll be glad to know December will carry a companion piece on con ditioning-water (or packaged boilers of the watertuhe type.' clMTUhIAL and ADVERTISING OFFICES: 1)0 W 4lad 8t. New Vert )t, ... C MtQftw, Pnaldenii WitUM Chevalier. EjceuUn Vlw-FftsU()tt>u ioonb A Qcrww, View i'Ctt*"' Tmmrcr; John I Seeretery: Paul Monieomerr, Sealer Vlee-ncaldani. Publicsliora Raise B Smith, Vlcc-PresJdeni and BdltaiUl Dlrecier: Neltoa Bead. Vlea-Pratdcat aad Dmnor ot - J s Ulscibum. Viee-Presldtm and Dlrectur ot Circultllen. -^ SUBSCRIPTIONS; Addren eofrapondence to Powu. SobicrtetlM Berrlcr. MOW 42od . New York T. Allow 6ne mrnvth Den i 4 SJ Pnvtwrr Personnel ... ___ .... ..___ _ . ___ _____________________ _________ r1 wvteei tin uilllito. centiiuriten firms, ieOiarlal and rtrvke ptaata. PoOUea aad ceapaar ~ ladJeatcd on tufawrlptioa orden. .... * eeptci: U.l. and poocnlqta. Canada SOT leeevpt mldj ter Hiadbook SI,00): all ptbef >*h.tl-Ju- Sutaicriptton nua--U.B. and U,S. penenleat: MOO rear, (0.00 tor two ran. (1.00 t*a. Canada: Sfi.00 tor one rear. SI0.C* * three yean. All other countries: uCcBr plarrotusaftet yttttf>t YMitLZ ** aniciea are taoeii rSyWwa lit own annual Indei. aad (be ffafbwevAu lads. Powsa Want to get .more and .-bqtter work from your maintenance crews? A Penn sylvania utility ho* some novel answers; an upcoming story spills them. i.. amt future menthi * This issue carries the second of B Phil Swain "Headwork" series giving the low-down on high-pressure steam, and we realty mean high--well above the critical. Watch for other stimulat ing articles by top authorities on super pressure problems and promises. **1* NOVEMBER 1953 3