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Steam & Excursion > NKP fire-ups, when you have a complete roundhouse…Date: 09/13/23 12:52 NKP fire-ups, when you have a complete roundhouse… Author: wcamp1472 Let's take a step back in time ---- say to 1956..
High Iron Co's master boilermaker, Joe Karal, told us of firing-up a Berk, after a 30-day inspection in the roundhouse. Upon arrival over the inspection pit in the roundhouse, while the machinists were all under and around the frame and running gear --- tightening-up loose hardware, the boilermakers were in the firebox --- hammer testing the staybolts, while the 'bolts are stretched-tight by modest boiler pressure. The fire and ashes had all been dumped and cleaned, exposing the grates.. while residual pressure in the boiler would be about 170psi, boilermakers would take advantage of the tightened firebox staybolts, in order to find cracked or broken firebox stays. About 30% of the stays ( mostly in the side sheets and firebox corners) were Flannery Flexible staybolts --- they weren't really 'flexible' , but they were made with a spherical head at the top of the bolt ( with a screw-driver slot), The purpose was to accomodate the larger fireboxes on newer manufactured locomotives. The larger fireboxes meant that as fires heated the water, the firebox sheets, necessarily expanded in length and width.. In smaller fireboxes, staybolts that were threaded in both the outer ( thicker) boiler sheets and the thinner firebox sheets ( 3/8" steel) had limited expansion problems. Their stays were commonly drilled up the center about 1 or 2 inches. The tell-tale holes, if stretched under modest pressure, would leak water during boiler inspections. The Flannery Flexibles had long tell-tale holes, from the bottom of the threaded end extending into the spherical head of the bolt -- to a depth of 1/3 of it's diameter. The tell-tale hole was copper-plated on it's interior. The copper plating was to ensure positive-electrical contact. Flannery bolts had the open ends of the tell-tale hole plugged with plugs made of pourous ceramic.... in case of a tear in the threaded region of the bolt, if the tear was about 50% of the diameter, it would leak water when stretched by boiler pressure. At annual hydrostatic testing,the ceramic plugs were broken and removed. ( the cermaic plug's purpose was to prevent firebox ashes, coal dust and fly-ash from plugging the hollow tell-tale hole). Since the outer end of the Flannery flexible bolts was a round ball in a loose fitting socket. normal hammer-testing inside the firebox was useless, for Flannerys. A 'rigid' staybolt ( threaded on both ends), when struck with an inspector's hammer will reveal a defective staybolt. The hammer blow is light and fast,..the blow initiates a shock-wave that is INSTANTLY reflected back to the hammer head, kicking-it away from the struck-end. Any cracks or tears in a rigid bolt will be instantly revealed. During testing, boilermakers go very fast, from bolt to bolt, in a steady rhythm ... However, if a defective bolt is struck, the shock-wave will not cross the crack -- - the bouncing hammer will stick to the broken bolt, as if it were magnetized .. interrupting the rhythmic bouncing rhythm of the inspector's hammer. He marks the defective bolt....and continues. All of the stays are hammered under positive bolier pressure. With Flannerys, the 'loose' end makes hammer testing useless.. Because the hammer’s shock-wave is dissipated in the loose-end of the ball-and-socket joint. Tte hammer head will not rebound - unless the boiler sheets are under pressure, and slightly stretched. The boilers, while under residuals steam pressure of about 50% of safety.valve settings, will have the all staybolts stretched under tons of stretching forces. So, Flannerys, to detect failures near the ball-head, as well as at the firebox ends --- Flannerys are tested when stretched by residual hydrostatic boiler pressure. The pressure stretches open any cracks -- that then leak out the telltale, in the bolt center. Flannery bolts do not have to be hammer tested. ( The hydrostatic testing pressure for qualifying broken bolts does not have to be the same pressure, as the FRA-required pressure of 125% of boiler operating pressure ). But, the critical aspect of Flannerys, is the open tell-tale hole, must be “proveably-open” it'sentire length. The purpose of the ceramic plug is to keep that tell-tale open, between "boiler hydroes"...( 'annual' to 'annual') The copper-plating of the holes is to provide Federal inspectors with proof that the tell-tale hole is open it's entire length. Flannery provided a flash-light testing tool. The tool has an electrically-insulated, long probe, with only the bare, sharp tip, exposed. When the inspector inserts the probe, into the telltale hole --- all the way, upon contacting the copper plating at the bottom of the bored-hole, the bulb in the test light illuminates -verifying simply that the hole is NOT blocked, and is open, it's entire length. So, at hydro-test time, after all the ceramic lugs are removed, 'hydro' pressure is used to stretch all the stays, as well as the Flannerys. Any tell tales that 'weep' water out the tell-tales, are obviously defective and must be renewed. If Flannerys have damaged, or missing ceramic plugs, the likelihood of getting thoroughly plugged tell-tales is a real possibility. The purpose of the battery 'Test Light', is to prove to inspectors that the telltale hole is open, it's entire length. If the Flannery hole is plugged with soot and cinders, it wil FAIL the 'Open-Hole' test. The inspectors regard a failed continuity test as a defective Flannery, and it must be replaced. DO NOT EVER USE A POWER DRILL TO OPEN FLANNERY STAYBOLT HOLES. You will peel off the conductivity copper-plating.... thus, the exposed steel wll be oxidixed over time, and will fail future conductivity testing.... all bolts failing the continuity test must be replaced... Now, back to roundhouse inspections.. The boilermakers take advantage of residual boiler prsssure, after the fire had been dropped, to hammer-test all the staybolts. Any Flannerys that are defective will seep water through the pourous ceramic plugs... Boiler prsessures need only be sufficient to stretch the firebox staybolts --- 100 psi, or better, will do fine to tighten-up everybody, and open up any cracks. Karal tells of times when non-leaking bolts, had broken off completely, inside the water-space of the firebox. Often times, the coin-like disk was stuck in the firebox sheet, ....and his hammer blow would knock it loose! when struck with a hammer would blow-out --- and boiling water would shoot clear across the firebox --- he always struck tested staybolts at arms-length, and always had the firebox entrance hole to his back ... in case of broken bolt, or other instant calamity. He always was conscious of having an instant escape route --- if needed. At the end of the staybolt testing, the boilers were drained, by blowing the hot boiler water into vertical hot-water, insulated, non-pressure, storage tanks. The storage tanks at Conneaut Roundhouse, were old loco boilers, repurposed and vertically mounted. They were insulated, and locos that are in for boiler-washes, blew-down their boilers into the vertical holding tanks. (Engines that were ready for the next road trip, after an inspection that had drained them, would be refilled with hot water from the roundhouse's holding tanks...) So, let's skip to the preparation steps, of returning the boiler to a roaring fire, and a bolier with water --- all ready for the next crew. At fire-up time, live steam from the power plant was piped to each of the pit tracks in the roundhouse. They had outlets near the smoke box and back, near the cab... Steam near the smokebox was connected to the fireman's 'blower' line at the base of the petticoat pipe of the loco's smoke stack. ( The blast nozzle from the cylinders, and the base of the smoke stack form the elements of a Bernoulli-jet vacuum arrangement to draft the fire on the grates in the firebox). The petticoat pipe is crucial so that the shaped-steam jet from the cylinders, is perfectly proportioned to get the widening steam jet to impinge the walls of tte 'stack. Also, from just above the curve of tye petticoat pipe, to the stack top, the stack's interior is an expanding cone .... all mathematically proportioned to form a properly-functioning Bernoulli jet, vacuum-forming stream out the stack. ( A common failure happens when the steam jet up the stack is angled such that the expanding steam-cone in the upper part of the stack, impinges too heavily on one side of the stack, and does NOT impinge on the other side..) After the roundhouse blower line is turn ON , and at work... The crew attaches another steam pipe to the tee in the engine's steam line to its stoker... At the same time, a crew connects the boiler blow-down valve to the pipe from hot water 'holding-tanks'... and fills the loco's boiler with HOT water --- near 180F... They add hot water, until the water level in the boiler is about 1/3 the way-up in the sight glass. The main steam valve for the stoker, near the roof of the cab, is temporarily closed... That way, the roundhouse steam only powers the needs of the stoker. Since the crew now has full use of the stoker they can cover the bare grates of the firebox with fresh ( 'green' ) coal. They'll add several scoops manually into the far, rear corners of the firebox. When the coal was sufficiently deep and even, they would prepare to light-off the engine... They used two, long-piped 'flame-throwers' , firing cross-paths onto the coal bed. The flame throwers used compressed air and fuel-oil for their fire. When ready, they light the torches.... in about 20 minutes, they've got about 30 psi in the boiler and 100% of the grate is ablaze! They begin to disconnect the roundhouse-supplied 'utilities',.. They also start the dynamos, the air compressors, test the injectors, and continue to build steam pressure --- it doesn't take long, and they'll call for the hostlers to move the engine to the Ready Tracks... the water will be topped-up in the tenders ( coal and sand were filled before the engine went into the roundhouse). And the 700 would be parked on the ready track --- all complete and ready to go.. All that done and ready, in 8 hours... That's the kinda' place that Doyie saw when he was in knee-pants ! Ask him about the engineer who admonished his fireman: "That's OK, boy, I only asked you to check the water in the tender, not to pack it DOWN!" * W. ( *that'll put a smile on his face !) Edited 7 time(s). Last edit at 09/14/23 00:19 by wcamp1472. Date: 09/13/23 17:48 Re: NKP fire-ups, when you have a complete roundhouse… Author: kennbritt Thank you for the very interesting and educational post.
Kennard Britton Date: 09/14/23 16:33 Re: NKP fire-ups, when you have a complete roundhouse… Author: wabash2800 --Oh, Oh, did he fall in the tender like a few incidents I heard about?
Victor Baird wcamp1472 Wrote: > Ask him about the engineer who admonished > his fireman: > "That's OK, boy, I only asked you to check the > water in the tender, > not to pack it DOWN!" * > > W. > > ( *that'll put a smile on his face !) > > > > Date: 09/14/23 17:50 Re: NKP fire-ups, when you have a complete roundhouse… Author: wcamp1472 Accirding to Doyle:
It was a dark night, and the crew that earlier had filled the tender, it was overflowed, and the covers were not over the open hatch.. So, the fireman stepped on what he thought was a closed hatch.. The engineer climbed the ladder to check out the commotion..... W. Date: 09/15/23 06:03 Re: NKP fire-ups, when you have a complete roundhouse… Author: Frisco1522 And treated water at that!
When did they start turning on accessories? We usually waited until about 180psi. Of course, all we really had was the dynamo and the air pump. Could test the injectors briefly too. Starting out with 1/3 boiler full of "cold" water would take it up in the glass quite a bit when heated. Would have been nice to have hot water or roundhouse steam like the RR did. Originally we lit her off on fresh pieces of 2x4 from a truss company next to the museum. Not an ideal thing. When we got to about 25psi, we would switch over to oil after heating it. After a few of those fireups, we put a Tee in the oil line ahead of the firing valve and had an overhead tank of diesel. Had a big air compressor that would run the atomizer and blower well enough to do the job. We also took care to take a long time to bring her up. You could hear the boiler creak as it slowly came up. We babied the boiler and it treated us well as a result. One thing, in the wood fireup days, leaving town pre-dawn and when you started working the engine hard, the ash would make a great firework show for a couple minutes. Date: 09/15/23 09:12 Re: NKP fire-ups, when you have a complete roundhouse… Author: wcamp1472 My preferred start-up method (coal) was a bed of old, cold ashes.
We'd hand-bomb a layer of 'green' coal onto the ashes, about 4" deep. Yes, 1/3 of a glass ( ambient temp water) was plenty... For light-off I preferred a full wheelbarrow of fuel oil soaked sawdust. At Ronceverte, WVa., & 2102, we had a busy sawmill as a neighbor, and they had mountains of stacked bark planks... they were free and burned well. We rare had luxury of sufficient volume of compressed air for artificial draft. Most of our engines had a netting-wall, with a large removable center section. We'd remove the center piece account the wet smoke particles could coat the netting, which meant sweeping it clear, several times until the bed of coal was ablaze. Rdg. 2100s, were equipped with 'Cyclone' front-ends. These were large diameter verical drums, similar to a snail-shell --- no netting. The drum was made of tough, abrasion-resistant steel. The interior face of the outer spiral wall was all large-size vertical ribs. When running at track speeds and a strong draft, the wind velocity in the drum was intense, whirling heavier fly-ash particles against the 'abrasion-ribs', The heavier the draft, the more likely to draw larger, glowing embers.. But, the greater the draft velocity, the harder the particles were abraded-down at higher centrifugal velocities ! At fire-ups, with no artificial draft, the air flow path was unobstructed by the hollow spiral-shaped drum. Back at the light-off.... We'd mix a big mound of sawdust with fuel-oil, and scatter the sawdust evenly across the coaled-over firebed. We'd encourage newbies to coal-over the grates using the scoop. After a lot of shoveling, they'd announce a completed task, ready for light-off. At that point, we gave them a flashlight, and told them to stick their heads through the open firedoors, and check the far, rear corners of the grate. Invariably, the far, rear corners were bare of fresh coal. That's how they learned how to 'fire' the rear corners --- a vital skill, when underway! ( Luckily, in the early days with 759 -1968/69, when NKP 759 was on home-rails, we became students of the assigned crews... happily, they still retained knowledge of operating and firing the Big Berks..the greatest lessons we learned --- by observation--- was their attention to the deep-depth of coal in those far, rear corners of the grates. The wind velocity at the rear of the firebox was the most intense of the air drawn through the grates.... the greater the quantities of oxygen, the more rapid the fuel-burn rate --- duhh!-- So, the NKP experienced crews, concentrated their attention on maintaining very deep "rear corners" and around the stoker firing-table. The rest of the flat grates burned evenly, under a steady draft.... One old-timer did take the time to explain an easy illustration about the bestconditioned firebed: Holding a scoop-shovel horizontal. he said that: "You want your firebed to be built and to resemble the shape of the scoop ---- Heavy and deep at the rear-corners, and a mass around the stoker --represented by the tapered steel surrounding the wooden scoop-handle ---- and a nice-and-flat area, like the wide part of the scoop .") So, having the NKP crews taught us a lot, not so much talking about what they were doing, but by the purposes of actions. Invariably, all the experienced NKP crews that we had, firing with a heavy-heel across the back of the grates, was their common practice ---- like riding a bike, once you know how to do it, it's easy!) So, with a now even layer of coal, and the oil-soaked sawdust scattered evenly across the grates, we'd toss in a couple of lit fusees, and close the firedoors... In a matter of minutes, the entire firebed was ablaze. and the coal fully involved. The sawdust burned off quickly, but the coal was already well-involved. The advantage of the soaked-sawdust was that it got 100% of the grate all lit and burning. That's important because any bare areas draw-in greater quantities of cold wind ... that robs the rest of the grate from getting a strong draft. So, again encouraging newbies, we'd make sure that they got used to "reading-the-bed" --- that meant letting the bright volatiles in the coal to burn-off, and start burning the carbon. So, after a few minutes of no coal feeding, you can study the conditions across the whole grate area.. Youre looking for dark spots --- where the carbon is now cold ash-- it's the dark areas of the bed where you want to aim your fresh fuel. A light, half-scoop of coal is easier to direct and land the fuel right where you want it. "Placement" is more important than "quantity". So, the firing-up process is a wonderful time to develop skilled firemen, as you bring-along eager newbies. A few become really dedicated and skilled.. Its magic for me, when I see newbies really grasping the skills, and learning very quickly the skills and techniques of managing hand-firing. Stoker-skills are much easier lessons to convey.... and most of my students are 'scoop-first', and use the stoker only when a heavy, steady draft... With large grates, and big engines, a few passenger coaches make only light drafts --- compared to 50 to 70 loads behind the tender. So, light drafts are the norm... also, with light-firing, and slow stoker-feed rate, bare areas are your enemies--- cold air coming through the grates really 'kills your fire'... soon, boiler pressure lags, you add more coal --- that cools-off the firebed, and black smoke at the stack. "Black smoke = cold firebed". Coal only burns when converted into a gas --- volatiles or carbon--- That conversion of states takes a great heat intensity. You want to add coal very strategically.... not just scoop-fulls dumped here and there. In the flames is where carbon --as a gas-- combines wirh the Oxygen-gas in the wind path. Getting fresh coal to ignition temperstures --- cools-off the grate areas where you've dumped the cold fuel.. Stokers are designed for heavier, sustained firing rates .... they're too clumsy for light drafts, and just sitting around... its those times you grab the scoop. I like to invite riders in the cab to try it. They're not any good at it, but, at low steam-demand --- that's OK--- learning, takes doing-it. The most challenging firing periods are long stretches of down-hill track profiles. Most of the time it's a light throttle, and very low draft. Keeping maximum boiler pressure is key to snappy air compressor strokes. Keeping the Main Resrevoirs FULLY charged takes the fastest piston-strokes from the compressors ---- even a little droop in boiler pressure slows down the compressor strokes--- which affects the replenish times in the train's air brakes' supply-line. During long descents, engineers use curves and their retarding effects, to keep the train's speed under control --- but, in long 'straights' braking is the only retadring effect ---- a light application uses a lot of stored-air. Repeated light applications is very dangerous --- the re-charge time takes 5 to 10-times longer vs, the quick times to apply the brakes. The only way to replenish the depleted service reservoirs is with full-flows of compressed air which occurs only during the times that the engineer sets the air brake handle back to 'running' , and supplying the full 110PSI, into the trainline. With full boiler pressure, maximum air-flow volume is crucial... that's why full boiler pressure during downhills is CRUCIAL. The compressors only effectively compress the air when they're operating at highest speed, piston strokes. Sluggish strokes don't stuff the air into the main reservoirs quickly enough, already near maximum pressure. ( some modern air compressor governors will use a higher 'Main Reservoir' pressure criterion --- 150 psi-- when the brake handle is advanced to 'lap' , or higher ... the faster compressor speeds, means a quicker release, and a greater volume of air, when the engineer returns the handle to running..). Full boiler pressure requires a bright fire on tte grates! Unlike the uphill, the strong drafts that make ideal use of the stoker EASY; whereas, down-hill, bright fires means that the scoop is your friend ---- the larger coal lumps in the scoop mean longer burn-times on the grates. So, I'll pay much closer attention to a fully-involved grate during the 'downhills'.... Firing a Big Engine is EASY on the uphill fight,, the engine almost fires itself ... ' Down-hills', takes skill and artistry.. Now you know! W. Date: 09/15/23 14:14 Re: NKP fire-ups, when you have a complete roundhouse… Author: Frisco1522 Repeated applications with high recharge time can lead to "pissing away your air". A very undesirable and dangerous situation.
Edited 1 time(s). Last edit at 09/16/23 06:13 by Frisco1522. Date: 09/15/23 15:18 Re: NKP fire-ups, when you have a complete roundhouse… Author: Goalieman Thanks for once again sharing your knowledge and experience, Wes! I never considered the effect that the draft would ultimately have on the air brakes. Add in light applications on a straight, downhill run and now I know that things can get “hairy” in a hurry if the fireman doesn’t know what he’s doing!!
Posted from iPhone Date: 09/15/23 15:18 Re: NKP fire-ups, when you have a complete roundhouse… Author: train1275 Frisco1522 Wrote:
------------------------------------------------------- > Repeated applications with low recharge time can > lead to "pissing away your air". A very > undesirable and dangerous situation. Keep an eye on the MR pressure, know your profile and railroad and consult your watch frequently ! Date: 09/17/23 13:27 Re: NKP fire-ups, when you have a complete roundhouse… Author: wcamp1472 Some diesel loco cabs were equipped with 'flow-rate' gauges.
They had a 'center-Zero' pointer that was very sensitive, and the needle deflection was an indicator of air-flow rates, and flow direction.. It was useful information, because the needle indicated the durection of the air-flow... either air flowing towards the train, or air flow coming from the train. The degree of needle deflection indicated faster flow rates of trainline air. It was helpful in indicating the "state of charge" of cars in the train... If it was indicating a relatively strong flow towards the train, the engineer could intuit that the cars' reservoirs were still charging, and requiring more air to reach the fully-recharged state. Making a brake application, means that the pressure in the trainline is below that stored in the individual Resrevoirs. If air has been used by a prior application, the pressure remaining in the reservoir is reduced. NOW, if an engineer wants to make another brake application, he must draw-down the trainline pressure, to below the residual pressure in the partially-recharged reservoir. He's very near a 'run-away' situation. Luckily, he still has a fully-charged "Emergency Reservoirs"... but, even THAT is only good for ONE stop. If he's stopped on a sloping grade, he's got a challenge ---- because releasing the brakes ( is the only way to get the reservoirs replenished ) --- means an instant run-away train! ( Disastrous run-aways have happened within recent memory..) He needs to recharge the entire train...but, to do that, he must get a lot of the cars' handbrakes wound up, really tight--- 'cause you can only re-charge the cars' reservoirs by 'releasing' the brakes ----- which restores the trainline pressure to freight train's standard pressure, of say: 80 lbs... Youre talking of upwards of 1/2 hour, or more to do the recharge. Typically, a long train will have a consistent, low, leakage rate --- various & numerous couplings and valves may each leak air at a very slow trickle--- but, many cars with tiny leaks--- will constantly draw air from the locomotive. And the air-flow indicator's needle will constantly be deflected ( by a small amount). A very "tight train" is a rare occurrence. So, the air-flow indicator's amount of needle-deflection, would give the engineer indications when the cars' tanks were mostly recharged, and the needle would revert back to a low flow-rate, typical for that specific train's characteristics. Some engineers paid attention, some engineers didn't understand the subtleties indicated by the flow-needle's movements..and they were un-influenced by it's actions. W. Edited 2 time(s). Last edit at 09/17/23 14:21 by wcamp1472. |