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STOKER INSTALLATIONS such ot the one pictured above require coreful itart-up procedure if they ore to perform efficiently Planned Start-Ups Prolong Stoker Life Expansion stresses and strofns in metal ports of sfolcer equipment reach maximum dur ing rapid temperature changes from shutdown to onthe-Hne conditions Operator hazards resulting from equipment failures or preparation oversights are most likely to occur during start-up e Oe/inife advantages of shorter start-up The start-up period is probably the most critics) tor any boiler equipment and it is at this time that potential hasards to operators are greatest. On the opposite page is o-set of detailed instructions that, if followed care fully, can be a major factor in completely eliminating accidents during this operation. This procedure shows how an Industrial power plant burning one-third million tons of coal annually on under feed and choin grate stokers outlines precautions token to assure that units are properly prepared for use. The unita that supplied die data for ihia discussion were: (1) 8-retort underfeed stokers equipped with Stirling boilers of 55,000-lb per hr steaming capacity at 22S psi and 500'F, and (2) chain grate stokers with 70,000 lb per hr boilers operating at 275 psi and 550 F. Actual operator's written start-up procedure records combined with equipment manufacturer's check sheets form the backbone of this material. Although the steps outlined here are admittedly very detailed, experience has shown that added care oi this point of boiler operation materially increases efficiency and adds to the life span of boiler equipment. periods can come only when operator follows carefully detailed lighting-up procedures Miitrlal for Ihia artIda wot adapted frwo Ltffkrtnf OB oo4 Ut Fwaaitnj Ft* Stti** Fir4 Bttitri, a umt try Ifeibcrt W. Asm Sttatn Dcpl Hnd. Power Division of Baslman Kodak Co, prvwm** at Ox Pali Mwtlns of itw Americas Social/ of Uadiamcol Eiiffa**n- 117s PUNT OPERATION ANO MAINTENANCE SECTION rowi* [NDERFEED STOKER Recommendations. SYSTEM! Open all superheater header drains and ismslic stop and chfck valve. Cheek steam line between iter nop volve and automatic stop and cheek by opening -in valve at boiler slop valve. When line Is dry, start bringI it up to pressure and temperature slowly with byposs Ire open oround boiler stop valve. When line is up to pres're, open boiler atop valve end close bypass valves. YIMO THE FIRE: Set stoker secondary ram control in third ich (first notch--tero motion), set stroke adjusting valves sero motion, start stoker-drive equipment, fill hopper, start bker and run coal onto grates until secondary rams are rered to approximately half their length. Uniformly distribute eight gal. of peteroleum fuel Igniter diesel engine oil jollied with aluminum soap) on coal in iortl near front well. Smear one side of wooden sticks with -iter and place to bridge ponds of igniter. This will act fuse. If fuel igniter is not available, pile wood one ft deep end vo ft wide adjacent to front wall. Pour kerosene on pile d use this for igniter. Ail SYSTEM: Close ash gates, sifting hopper gates, .windbox access door, furnace doors, damper, front-wall sad-side-well :ondary sir dampers. Open rear (stack) damper to min imum position on regulator. Place forced draft regulator in terries to maintain automatically 0.1-in. (umaee draft. RAISINO PRESSURE: Remember, to establish good ignition ot front wail, slowly cover grates with fuel end obtain and main tain straight open burning lanes over tuyeres. To'prevent domage, allow two hours from lighting time untii-unll goes on line. Light igniter with torch through both front wall doors. When coal is ignited completely across front-wall (approxi mately five minutes after lighting), start stoker at minimum speed in low gear. Lengthen secondary ram stroke as much as possible* without losing ignition at front vwall. ` Increase opening of rear domper as much as possible without effecting capacity of remaining units in service. 11 , When pressure reaches 25 psi, throttle inlet' superheater header drain to one turn open. When pressure reaches 100 psi, blow down feedwater regulator and blow down water col umn. As active fuel bed moves onto grate, apply, normal atroke of 5-in. agitation, 2-in/push. i Stoker may be stopped to regain ignition at front wall, but to avoid damage, it should run at least one revolution every ten minutes. AFTER OOINO ON LINE: When boiler is on line, close super heater header drain valves. Manually lift stl safety valves (four 3Vk-in. valves on boiler end one 2-in. valve on super heater). Enter record of boiler, volves and date In Equipment Record Book, use separate page for eaeh unit. Place feed water regulotor, phosphate feed and continuous blowdown systems in service. Open impulse connection from steam drum to feedwater pump governors. eCHAIN GRATE STOKER Procedure. ! fTIAM SYSTEM: Open ell superheater header drains and 'automatic slop and cheek valve. Check steam line between f header slop valve and automatic atop by opening drain el header slop valve end venting at automatic stop and check nKe. When line is dry, bring up to pressure with bypass to header stop valve. When line is up to pressure, open header stop valve and close bypass valve. UY1NO THE FIRE: Carefully raise regulating gate to at least " 12 in. Drop feed plates and frames to lower position. Spread 6 to 8-in. layer of coal under ignition arch and over No. I 'compartment. Just beyond the feed plates, make a shallow trough in the coal running entire width of grate. Uniformly distribute four gal (5 gol (or No. 7) petroleum fuel igniter in this trough. Petroleum fuel igniter la non-toxic and usually harmless .to skin. As with kerosene, store igniter in covered container way from excessive best. If fuel igniter is not available, o*e wood end kerosene os o substitute in the same manner * described above. AIR SYSTEM: Gose nil setting access and inspection doors and ash galea. Close oil stoker air compartment dampers. Open rear (alack) damper tight-closing device, then damp damper about ^-open on regulator. Open windbox damper about half way and damp. RAISINO PRESSURE: Light fuel igniter with torch. When coal adjacent to igniter is burning, slowly open No. 1 air com partment damper and adjust to maintain furnace draft of -0.1-jn. water. Lower cool gate to about 8 In., raise feed piste fromes end seeure with pins. Run stoker et minimum speed and add fueL Bui don't fill hopper until entire bed is burning briskly and ignition arch is hot. Open cOal bunker grates and latch up coal spout swingers. When fuel bed reaches second compartment, gradually open its damper and readjust No. 1 and stack dampers to main tain furnace draft aa above. It should not be necessary to break up fuel bed with- bar at any time. Turn on cooling water on rear stoker roll. If wood is used for ignition, follow ssme procedure, but allow more time for ignition and spread additional coal on top' of briskly burning wood. At 25-psi pressure, ctose inlet superheater header drains. At 150-psi pressure, blow impulse lines to feedwater regula tor and water column. AFTER GOING ON UNE: When boiler is on line, close out let superheater header drain, place furnace draft controller in service, adjust stack damper to suit load, open continuous blowdown valves, start secondary air fan and place feedwater regulator in service. Manually lift all safely volves. Enter record of boiler, valves and dale in Equipment Record Book. Use separata-page for each unit and sign each entry. OECEMtEft IU3 PLANT OPERATION ANO MAINTENANCE SECTION 117b