Pressure Records and Fuel Waste.

Pressure Records and Fuel Waste.

PART II.

In the same establishment, only two months later, on New Year’s morning, the night watchman closed the furnace door at the usual hour, so the fires would be in better condition for the day fireman when he arrived; but the day man did not arrive until some two hours later than usual, as it was a holiday, and so the steam went up again, and startled the neighborhood with the racket for an hour or so. The day man claimed that he told the watchman not to close the doors until a later hour, which the latter denies. Be it all as it may, in both instances the chart daily submitted to the manager of the property, revealed the occurrences, and brought forth an investgation resulting in more correct methods of transmitting orders and causing the unhooking of the regulator while under “bank tires,” and also in the night watchman making more frequent visits to the boiler-room. Who can deny but that in this instance their indifferent methods would ultimately have resulted in exploding their boiler, had not the Edison recording gauge unmasked the facts, and caused the proprietor to set some needed rules in force? If an ounce of prevention is better than a pound of cure, the instrument repaid its first cost in these two instances alone.

Self-interest should suggest the useof such a safety appliance, particularly inasmuch as all persons are supposed to intend the natural consequences of their acts; for proof of an act or course of procedure which was adopted or persisted in to deceive the public, or in defiance of its safety, is sufficient proof of the intent to deceive and jeopardize, unless the doer establishes innocence of such intent and knowledge, and the burden of proof rests on him. If, therefore, it be true that no steam-boiler plant can be conducted as intelligently, economically, or safely without the information and aid supplied by the pressure-recording instrument, as with it, then proof of negligence can be made out by establishing the fact that such a valuable monitor and means of information as the pressure-recorder had been re. jected, and failure to secure such competent attention may properly be urged in courts of law as evidence of negligence.

Even so important a matter as the amount of pressure applied by an authorized inspector in testing a boiler with hot water, has shown that only an excess of eight pounds was put upon an old boiler which is regularly carrying from fifty-five to sixty pounds pressure to have “jumped on ” for an instant, and then released, allowing no time for careful inspection of the seams, etc., while under the testing pressure. No satisfactory reason has been obtained, so far, for this improper method of testing ; but the fact has been established, and so much gained. Certainly more confidence could be reposed in a test where the record shows that the boiler sustained the testing pressure for five or ten minutes, and during which time the testing engineer could be presumed to have been examining the boiler for evidence of effect under such strain.

Another matter revealed frequently by the Edison guage chart is the habit indulged in by many attendants, called “bottling up steam.” The most frequent occurrence of such habits takes place at a few moments before the starting time in the morning, and at noon, and in some cases just before cleaning fires. Of course such prejudicial habits are the simple outgrowth of ignorance concerning the limited amount of steam in quantity they can so bottle up, and the very small service it can render, compared with the injury such practice, when persisted in, ultimately does the boiler. Aside from this objection, the habit is exceedingly pernicious, because only a few moments neglect would cause the pressure to accumulate to the point at which the safety-valve is supposed to open ; then, if it hap pens to be inoperative, an accident is almost certain to follow. No excuse should be taken in any shape, under any kind of reasoning, for “ bottling up steam.” If the generating capacity of the boiler is not equal to the current demand, it cannot be helped by simply bottling it up ; in fact, it had been my experience, that, where the record line has been extremely crooked upon the first introduction of the recorder, the effect of such introduction has been to cause a much more uniform line from day to day, until the nearest approach to uniformity had been reached, consistent with the vicissitudes of the demands for steam. A steam user once apologized for the appearance of his record, saying that the steam was drawn from the boiler at irregular periods by persons in the mill, and consequently the firemen could not carry any very regular line; that his use of steam was different from that in most places, etc. Noticing, apparently, my incredulity, he asked if I disagreed with him. My reply was : “ Do you suppose that the steam necessarily falls as low as this record indicates? In other words, I called his attention to the fact, that, where a fireman is on the keen look-out for his boiler pressure and water level, he will readily detect the pointer-hand of his guage the moment it begins to rise or fall, and govern himself accordingly. For instance, if he sees the hand indicating that the pressure is falling, he will avail himself of the opportunity to slow down his feed, and perhaps open his damper wider, and, if his fires are in prime condition, withhold fresh coal for a few moments ; then when the onslaught upon his boiler has ceased, and the hand of his guage is stationary, or starts to move upwardly, he will at once set about it to replenish his coal and water, and so have his conditions favorable in a few moments for another attack upon his steam supply. When his steam is rising, he can afford to feed and to fire, and his thought should be to have everything in prime condition while he has surplus power and opportunity. Then he would not be caught so badly when these extreme attacks were made upon him. The cause of these extreme fluctuations, then, are largely due to the fact of his being unprepared to meet these emergencies, and becoming alarmed when his steam has fallen twenty or thirty pounds, he attempts to get it up by replenishing his fire, as it seriously needs it, with coal, which only tends for the time being to reduce the pressure still more, until it has been capable of delivering its gases, ready for combustion. After this little explanation, the proprietor shook his head, and said he never had thought of it in that light, and that he would have to call John to him, and have a t,aik with him. Now, the result of this was, that, from that time on, the man’s record never fluctuated in the same manner again, and the average steam line maintained was one which showed constant attention to firing frequently in small quantities, and keeping himself in shape to meet these emergencies. Undoubtedly, the man had to work a little harder at first, but afterwards it was easier when he properly understood the matter, and manipulated his fires accordingly. The suggestion from the proprietor was exceedingly valuable. It resulted in the proprietor teaching his man, and in mutual regard between them afterwards, because it showed that the man was capable of being taught, anti also willing to be, and that the proprietor had evidence of the resulting fidelity. The dissemination of knowledge among firemen can certainly do no harm, and when it reaches a man who desires to hold his position, and give satisfaction, it will do much good. Men uneducated to the science of what constitutes firing steam boilers, can hardly be expected to use that knowledge which others possess professionally. Some men will fill a furnace full of coal, so as to have more time to walk around ; then after a time up goes the steam pressure, because more heat is generated than is wanted ; then the feed water is turned on, and the water level run up so as to keep the steam pressure down ; the safety-valves may blow or not, the damper is closed, the fires smoulder, large quantities of carbonic-oxide gas go up the chimney, and this means an escape of unconsumed fuel, which means dollars and cents. After a while the fires burn lower, and down goes the steam—helped down, it may be by another dose of coal ; and so we can imagine the final effects upon boilers used in such a manner. The position of a fireman may be considered an humble one by some folks, but he is a man, for all that, and his pride in what he can do is a stronger spur than anything else. Let him see that you care for what he is doing, and take a careful interest in his work, and let him understand furthermore that his own grading depends upon himself, as established by his records ; then you are in a fair way to have confidence in your man and in your safety, and also feel assured of economy of fuel. But eventually you must pay him what he is worth. If not, some one else will be glad to have him. Suppose, for instance, a man who burns three tons of coal a day is paid two dollars for such service, and that in so doing he is wasting as little as ten per cent. If coal costs four dollars and a half per ton, the loss will be one dollar and thirty-five cents per day, or what is equivalent to paving a man three dollars and thirty-five eents per day who can save this amount ; but when amounts of, say, eight thousand tons per per month, are used, the saving of only ten per cent, amounts to eighty dollars per day, and a small portion of which, if offered as a premium to the men who use this coal, would go a long way towards saving the remainder of this money.

What is wanted is the maximum of steam per dollar’s worth of coal burned ? Much can be saved by the manner of its use, and it is within limits furthermore to say that from five to ten per cent, is commonly wasted, while from thirty to forty per cent, is frequently gotten rid of by fireman not qualified as such, and entirely ignorant or indifferent regarding the science of complete combustion. Certainly it is of vastly more importance to a proprietor, both on a scope of safety and economy, that his fireman shall be a man trained in the art of properly burning the fuel supplied him, than that his engineer shall know particularly if the latter does not impart the information to the fireman. The practical value, therefore, of the steam record is, in this connection, that it compels the fireman to give close attention, maintain unform water level and uniform steam; and these cannot be had with anything short of the closest scrutiny, which means economy of fuel, and safety as well. The explanation of the charts has given much information touching unexpected occurrences, but innumerable other instances might be recited which would only tend to exhibit the surprisingly large number of unsuspected occurrences possible wherever steam is used; and as these facts become more generally known to those who are not at present deriving the information from such instruments, their use will be extended, and more correct methods of caring for steam boilers under pressure will be inaugurated, ultimately resulting in not only greater economy of fuel, but in a greater degree of immunity from those disastrous explosions which destroy so many lives and so much property annually

Pressure Records and Fuel Waste.

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Pressure Records and Fuel Waste.

JARVIS B. EDSON, M. E., NEW YORK.

The engineer of the present day begins his operations based upon the pressure of steam he is capable of maintaining in his steam boiler. From this he extends his calculations, and elaborates his plans for the prosecution of his work. It matters not what the problem may be—whether it is the grain to be threshed, grist to be ground, hill levelled or mountain pierced, ore raised or office reached, ocean ploughed or continent crossed—the same agent performs them all. The tropical fruit while rushed to a Northern market, is also cooled by it, and the plenteous meat of the Western plain is refrigerated during its trans-continental run, and we see the coal transformed into heat, then into steam, and finally manifesting itself in work, in its production of cold; exemplifying the beautiful law of the conservation of energy, and making us thankful for the birth of steam. At present the civilized world is lighted by electricity, and searching for one greater than Faraday who shall give us a substitute for, and sound the death-knell of steam. So meanwhile, we reconcile ourselves to the loss passing up the chimney, and stand aghast when the boiler “ lets go,” scattering death and destruction in its wake, and simply conclude with a verdict of “nobody to blame.” Investigation and scientific study have done much, however, both for the construction and the safe and economical management of steam boilers. Mystery no longer accounts for their explosions, for the conclusion has been reached that “ the causes of such accidents can be wholly prevented and controlled,” and ignorance is becoming dethroned in her sway, to make way for the more intelligent methods of boiler management. The men from our colleges and technical schools demand the facts, that they may proceed to their conclusions. Not theirs to view the one hundred victims of a “ Westfield” explosion with “ nobody to blame for it is not they who beat upon pans, and blow horns, to scare off the devil when the sun darkens. The solar eclipse to them was calculated upon, and predicted in advance of its coming. Their verdict will always be: “ Somebody is to blame,” Explosions are caused by ignorance or neglect.” And so with economy, for to them the furnace will be a sort of gas retort, and the burning of coal a scientific study. To them, the boiler is a giant struggling against almost equal odds, harassed by conflicting expansions and contractions, constant and varying strains, attacked by corrosion, and injured by scale. They will know it as a magazine of enormous power, in which each cubic foot of water has the explosive energy stored within of a pound of gunpowder, and to them eternal vigilance will be the price of safety. C ertainly, then, it does appear strange that for such a charge we should employ cheap labor, and that the most ignorant man about the establishment is the favorite fireman. For my part, it is incomprehensible how either practical men or those of the usual amount of business sagacity can feel willing to discount the chances against such a course.

Nevertheless, the engineer of to-day is confronted with these conditions, and the safety and economy of his plant become of imperative importance to his success.

Upon the question of safety, it requires no demonstration to prove that whatever impairs the boiler’s strength or durability should be prevented. To make such prevention possible, however, presupposes the means whereby the preventable occurrences may become known. If, therefore, fluctuating or excessive steam pressures are injurious, how are we to be made aware of their occurrence ?

Obviously but one method exists, and that is the resort to automatically steam-written records of them, from which we can determine the departure from conservative limits. Assuming that the ordinary steam gauge, which only indicates the pressure at the instant, is entitled to the great confidence bestowed upon it, it undeniably lacks the ability to afford us any more information as to the pressure of the previous moment than the proverbial dead man who can tell no tales. In fact, for many years, owing to sharp competition, they have been so poorly constructed as to be even dangerous to use, so liable are many to rely upon them for the determination of the pressure they are at the time carrying, even going”so far as to adjust their safety-valve weights to elbow with the gauge. The dials are first produced by different methods, in large quantities, all alike, and the springs taken afterward which will come the nearest to the “travel” called for by the dial so laid out: whereas each spring has its own “ travel,” and its dial should be laid off accordingly, and a suitable price demanded for the article when made, as a cheap and unreliable steam gauge is dangerous and dear at any price.

When, however, only one of these is relied upon for twenty years, it is apt to be considerable out. Instead, therefore, of relying solely upon the ordinary indicating instrument, whether it be entitled to such confidence or not, common prudence would dictate the employment of more than one gauge, and preferably that the supernumerary would be a recording machine. The records of steam pressure carried have large prudential value, for the reason that, with their use, a fireman must give up his position, or do what he is required to. For instance, if a careless man lets his steam get too high before he discovers it, and the ‘‘safety-valve” (?) does not blow as calculated upon, from any of the causes common in such cases, who other than the foreman will be any the wiser? and when will the remedy for a careless fireman, or faulty or overloaded safety-valve, be applied?

It is generally supposed to be necessary to first know of a trouble before its remedy can be either determined or applied.

The only way, therefore, to know whether one’s boilers are being exposed to excessive pressure or not, is to use a guage which records the pressure.

Occurrences are constantly taking place under that smoothsounding term “embanked fires” which would electrify every hair of one’s head if revealed to those who have so much at stake, and think such a fire harmless. A strong fire towards stopping time leaves the boiler setting so hot as to supply sufficient heat for running up the pressure beyond what a cold setting could do. Vet, when the fires are once “banked,” the man “lets up” on his watchfulness, and generally the boiler is left entirely alone for a long interval. “We never carry steam at night, as we bank ourlires, and in the day-time have a good careful man around,” is an expression common to moet steam users; but a few moments will generally convince them that they have assumed a very ridiculous and untenable position. The police of our cities frequently find steam blowing off from a boiler under the sidewalk during their night perambulations, and have learned that it means one of those places where they “never carry steam at night;” anti they rout out somebody in the building or neighborhood to remedy the trouble. A case occurred some time ago under one of the costliest buildings on Broadway, New York, where fires are banked and they “never carry steam at night.” It appeared, however, from the Edison recording guage chart the next morning, that something had caused the recorder to make a high steam line for a good part of the night, and investigation proved that the night watchman heard a roaring noise when in the top of the building, and concluded it must be the boiler “blowing” about something; so he clambered down twelve or thirteen stories, and found the hamper closed, and a full pressure on. Of course it goes without saying, that if the safety (?) valve had been fast in its seat, as they frequently are, or the weight shifted on the lever from any cause, a first-class explosion would have followed. The boilers are provided with an approved pattern of damper regulator on the main flue, and also have individual dampers on the branches from each boiler leading into the main flue. The individual dampers are, of course, for shuttings off either boiler when not in use. The trouble was caused by the fireman not knowing enough or forgetting to unhook his automatic regulator connection before leaving for the night: and so when the banked fire and heated walls had radiated sufficient of their heat, the pressure of steam closed the damper, and the heat being entirely shut in, and no cold-air passage left open to the chimney, and little or no steam being used in the building, the safety-valve was called upon, and fortunately .did its duty, and prevented the steam passing beyond the limit as shown by the chart.

(To be Continued.)