US545376A - petersen - Google Patents

Description

(No Model.) 5 Sheets-Sheet 1.

E. PETERSEN. TUBULAR BOILER.

No. 545,876. Patented Aug. 27,1895.

5 Sheets-Sheet 2.

(No Model.)

E. PETERSEN. TUBULAR BOILER.

No. 545,876. Patented Aug. 27,1895.

O O O O O (No Model.) 5Sheets-Sheet s. E

- E E. PETERSEN.

TUBULAR BOILER. No. 545,376. Patented Aug. 27,1895.

(No Model) 5 SheetsSheet 4. E. PETERSEN. TUBULAR BOILER Patented Aug. 27, 1895.

E. PETERSEN,

( 5 Sheets-Sheefifi.

TUBULAR BOILER.

Patented Aug. 27, 1895.

UNITED STATES PATE T nron.

ERNEST PETERSEN, OF LONDON, ENGLAND.

TUBULAR BOILER.

SPECIFICATION forming part of Letters Patent No. 545,376, dated August 27, 1895.

Applic i n fi d November 22,1894. Serial No. 529,615. (No model.) Patented in England December 7, 1893. 170.23,.577; in

Belgium May 4, 1894,1010. 109,769; in France May 12,1894, N0. 238,4=B4; in Italy February 7, 1895, LXXIV, 375; in Himgary February 11, 1895, No. 2,150, andin Austria April 30,1895, N0. i=5 l,523.

To all whom it may concern.-

Be it known that I, ERNEST PETERSEN, a subject of the Emperor of Russia, residing at 5% Nelson Square, Blackfriars Road,London, in the county of London, England, have invented certain new and useful Improvements in Water-Tube orTubulous Boilers, (for which I have obtained Letters Patent in Great Britain, dated December 7, 1893, No. 23,577; in Belgium, dated Mayei, 1894,No. 109,769; in France, dated May 12, 1894, No. 238,484; in Austria, dated April 30, 1895, No. lo/1,523; in Hungary, dated February 11, 1895, No. 2,150, and in Italy, dated February 7, 1895, No. LXXIV, 375,) of which the following is a specification.

My invention relates to that class of water-- tube or tubulous boilers in which waterchambers arranged on each side of a fire-grate are connected toa separate water and steam chamber above the fire-grate by a number of watertubes of small diameter placed close together, so as to offer a comparatively large amount of heating-surface to the flames and combustion-gases which pass transversely through the interstices between such tubes on their way to the uptake.

My present improvements have mainly for their object to obtain a very greatly increased amount of heating-surface in the said watertnbes, as compared with the constructions of such boilers as heretofore proposed, while very greatly reducing the number ofjoints required to be made between the water-tubes and the water-chambers, in addition to which a great number of further advantagesare obtained thereby that will presently be referred to.

The invention consists mainly in substiiuting for the separate small tubes which in existing water-tube boilers connect the lower water-chambers to the upper water and steam chamber, groups of tubes somewhat similar to those described in the specification to my Patent No. 475,150, but whose ends, instead of being secured in open cups, as there described, are secured in closed cups or chambers, from one of which a single tube extends down to the lower water-chamber of the boiler, while from the other a single short tube or neck passes through the upper steam and water chamber and is secured on the inside by a screw-nut. By this arrangement the following advantages are obtained over the existing constructions: In the latter the numberof separate tubes that can be grouped together on each side of the boiler is limited by the distance which it is necessary to keep their ends apart where they are fixed to the upper and lower water-chambers, in order, on the one hand, to afford the requisite room for the screw-nuts or other means of fining, and on the other hand to retain sufficient strength in the walls of the Water-chambers to withstand the steam pressure.

With the improved constructions, as there is only one connecting-tube to every group of say seven heating-tubes, there isno such limitation to the closeness to which the tubes may be brought together, and as a result more thandouble thenuinberofheating-tubes could be brought into the space which the single tubes occupy in existing constructions. Again, with existing constructions a great proportion of the length of most of the watertubesnamely, from their connection with the lower water-chamber upward-is out of line of the draft of'the furnace, and is therefore useless for raising steam, constituting so much useless expenditure and dead weight.

With myimproved construction, there being only one connecting-tube to every group of seven or more heating-tubes, such length of tubing that is not efiective for raising steam is reduced to oneseventh or less of that of present constructions.

These are the main advantages of my improved construction, but, as before stated, there are numerous others, resulting from the general construction of the boilers, which I will proceed to describe with reference to the accompanying drawings, in whicha Figure 1 shows a part end elevation and part transverse section; Fig. 2, a side view; Fig. 3, a plan; Fig. 4, a horizontal section on line X X, Fig. 1; Fig. 5, a cross-section on line Y Y; Fig. 6, a cross-section on line Z Z; Figs. 7, S, and 8*, enlarged sections of the cups and heating-tubes. Fig. 9 showsa. part section at W XV. Fig. 10 shows an enlarged part section of a modified form of the watertube connections. Fig. 11 shows a section of a modified connection of the upper cups of the water-tubes. Figs. 12 and 13 show sections of two arrangements of safety appliances for the lower ends of the water-tubes.

The boiler as here represented is arranged to have its furnace served at the one end only. It may, however, be served from both ends. 4

A is the, fire-grate, which may be of any known construction. On each side hereof is a tubular waterchamber B B, While at a suitable height above it is the water and steam chamber 0. The chambers B are connected to the chamber 0 by means of groups of watertubes D, secured at each end in cups E E, of which the outer cups E are secured by a screwed joint to tubes F, the lower ends of which are connected to thelower water-chamber B, while the inner cups E pass with their necks through the sides of the chamber 0, and are secured inside by means of screwnuts I and washers J J. There are shown provided five horizontal rows of these tube groups on each side of the furnace; but there may be any greater or less number of such rows, the length of the tubes D between the cups E E being varied in the different rows, as shown, so that the whole of the same come within the effective draft of the fire, and it will be seen that each row is arranged more or less at right angles to the direction of the draft, so that they are in the most effective position for taking up the heat from the flames.

Of the several rows, the two lower groups, which take up the greater part of the heat from the flames, are connected separately by their connecting-tubes F to the water-chambers B, while the upper three groups are all connected to branches on one and the same connecting-tube F. For the attachment of the connectingtubes, the cylindrical waterchambers B are formed with three longitudinal broad ribs B B .8, having passages at distances apart corresponding to the distance apart of the successive connecting-tubes of each row, these ribs being in such positions that the one for the tubes F of the upper three rows is at top, while those for the tubes F of the two lower rows are arranged below, the object of this being to allow of the lastnamed connecting-tubes being formed with a considerable curvature, as shown, in order to allow of the free expansion and contraction of the tube groups, due to variations of tem perature, without straining any of the connections.

Owing to the fact that there are only three rows of connecting-tubes to be attached to the water-chambers B it will be seen that these can be made of the smallest possible diameter consistent with an adequate supply of water to all the heating-tubes, such water being supplied through the large circulating-tubes V G that connect the ends of the lower waterchambers B with the water-space of the upper chamber O. The water-chambers B B are preferably cast either of gun-metal or'of soft steel.

The groups of tubesD are secured perfectly steam-tight in their cups E E, preferably by shrinking the latter (which are eitherof caststeel or wrought-iron) onto the ends of the tubes, this being effected by making the holes in the cups slightly smaller in diameter than the tubes, so that when the cups are expanded by heating to a red heat the end of the tubes (cleaned and accurately turned) will just enter them. On cooling the cups will then grasp the tubes as firmly as though they were of one piece. The tubes may either be of steel or of copper or brass. By preference I make the two lower rows of steel and the upper rows of copper or brass. The cups may either be formed conical or they may be bellied as shown in the enlarged section at Fig. 7. They may also either be circular for the reception of seven tubes, as at Fig. 8, or the fiat face may be made square with rounded corners, so as to afford room for nine tubes, the tapering part being kept conical at the smaller end, as at Fig. 8*. The tube groups are made to decrease in length in the upper rows as the hot combustion-gases, in becoming cooled considerably in passing the lower rows, will decrease in volume, so that a less width is required for the passage leading to the uptake, the length of the tubes D being strictly limited to the effective heating-space of the furnace, this space being confined by sliding shield-plates H, which are slid in between the rows just beyond, the outerv cups E being made to rest upon the connecting-tubes F and against the screw union-pieces E The longitudinal slits that are thus left between the contiguous plates are also closed in by means of comb-like slotted plates H, that are slid in between the rows and are then dropped with their slots over the union-pieces E It will be seen that these shield-plates protect not only the union-pieces E but also the tubes F from immediate contact with the flames and combustion-gases, and as the screwed joints that connect the cups E with the chamber O are inside the latter and always in contact with water and steam there are absolutely no tube-joints that are directly in contact with the fire. The screwed joints within the chamber 0 consist of a nut I, by preference of gun-metal, a recessed washer J and a washer J of asbestos or other suitable material which by the action of the coned inner surface of the washer J is forced not only against the surface of the chamber 0, but also against that of the neck of the cup E, so as to form a perfectly steam-tight joint, which is in addition assured by the tight fit of the coned surface of the cup against the correspondingly-coned surface of the hole in 0.

As the upper rows of tube groups may be liable to have soot and ashes deposited between them, I provide them with scrapers K, consisting of plates having holes of such a screwed onto the neck.

size as to be capable of sliding freely backward and forward upon the tubes. These scrapers have rods K attached to them that extend outside the casing, so that by means thereof the scrapers can from time to time he slid backward and forward upon the tubes in order to clear them of soot and ashes. It will be seen that should at any time one of the tube groups become leaky or defective it can be readily removed by unscrewing the connections with the water chambers B and O. In the case of the three upper tube groups such removal is facilitated by forming the connecting-tube F with an oblique flangejoint at F. arranged closely side by side, so that the cups E E almost touch each other, as shown at the enlarged section at Fig. 7. By this means the spaces between the contiguous tube groups are only slightly larger than the spaces between the individual tubes of each group, so that the flames and combustion-gases will pass freely in between the latter and in becoming repeatedly split up and mixed together in their passage a more complete combustion of the smoke and combustible gases will be attained. A perforated shield X may be provided in the upper water and steam chamber over the openings of the cup E E, in order to prevent the water and steam issuing from these to be projected with too much violence into the chamber, and thus to prevent primmg.

Fig. 10 shows a modified arrangement of the connection of the compound tubes D with the lower water-chambers B. The two lower rows of the compound tubes are connected to the curved branches F F of a tube F, fixed with a flange on a circular boss B on the upper part of the water-tube '13, instead of each compound tube being connected by a separate curved tube to the lower part of the tube B, as in the first arrangement. By this means, while the curved branches F still allow of the free expansion and contraction of the compound. tubes without straining the joints, the advantages are gained, first, that there is only one joint with the tube B, instead of two, and,

secondly, this connection, being at the top instead of at the bottom of B, there is no liability of its becoming choked with deposit. The bosses B of the tube B alternate with bosses B for tubes F connecting the three upper rows of compound tubes, as in the first arrangement.

Provision may be made for preventing accidents and the stopping of the boiler on the bursting of one or more tubes of a compound tube, as shown at Figs. 11, 12, and 13. At Fig. 11 the neck of the upper cup E of the compound tube is extended beyond the nutI and is formed with a circular edge, on which rests a valve a, guided by an open cap I), When the boiler is working, the valve (1 is kept open by the up ward flow of water and steam from E, but should one of the tubes D burst the clown- The tube groups of each row are ward flow caused bythe escape of water and steam will cause the valve or to close down on its seat, and thus the further escape be prevented. The escape is in like manner pre vented at the lower end by adapting the branched tube F, Fig. 12, of the two lower rows, as also the tube F, Fig. 13, for the three upper rows to contain a ball-valve c in a seat (Z, so that on the bursting of a tube the increased speed of flow of water through F will carry up the ball-valve 0, so as to close the branch through which the escape is taking place, as indicated by the dotted lines. One of the branches is made sufficiently large for introducing the ballc through it, and a lining e is then fixed to serve as a seat for the valve. If necessary, two ball-valves may be provided in the tube, one for each branch.

At Fig. 11 is shown a convenient mode of forming a water and steam tight joint between the cups E and the chamber 0. It consists in introducing a small copper ring fbetween the two, which, on the screwing up of the nut I, will constitute a steam and water tight packing, thus preventing the necessity for producing an accurate fit between the coned surfaces of the cup and the chamber.

Although in the foregoing I have described the boiler as composed of two bottom waterchambers and a single upper water and steam chamber 0, it is obvious that there might be two or more upper water and steam chambers arranged side by side and communicating with each other.

The boiler is inclosed by a wrought-iron casing L, in which is a removable ash-pit M, carrying the fire-grate. The ends of the casing are formed with doors L, through which access is gained to the tube groups and for the introduction and removal of the shield-plates, and the tubes are also accessible at the sides, the plates L being hung at top by means of hooks onto tubular supports N and secured at bottom by fastenings 0, so that on releasing these the side plates can be removed. The tubular supports N, as also the uptake P, may be carried by trussed saddle-shaped supports Q that rest upon the ends of the upper steam and water chamber 0, this being in its turn carried by the return water-tubes G and lower water-chambers. B, that are carried on supports R, forming the bottom of the boiler-casing. The back end of the latter is by preference constructed as shown in Figs. 5, 6, and 9-namely, as a non-conducting shield S, built up of sheet-iron S and S with an intermediate sheet of glass S packed with slag,wool,

or asbestos.

At the inner side of the shield S is a fire-- brick lining T, forming the back of the furnace, and built up of a number of fire-clay blocks of a shape to fit against the two side water-tubes and the under side of the steamchamber 0. These blocks are so formed that when placed in position they are securely held together by key-blocks T, secured by bolts T as shown at Fig. 9.

IIO

Within this lining I of tube groups.

may be arranged a feed-water heater U, also.

formed of tube groups similar to those at D, through which the feed-water is supplied either to the bottom of the upper steam and water chamber 0 or to the lower water-chambers. The sides of the furnace-chau1ber are also formed of fire-clay blocks T which extend up to the lower cups E of the first row The forced air supply isalso made to pass through tube groups V,situated in the uptake, so as to be heated on its way to the ash-pit through thepipesV. the steam passing off from the steam-chamber C may also be'made to pass through asuperheater composed of tube groups WV situated in the uptake. Both these and the tube groups V are provided with scrapers Y, operated by handles Y in the same manner as those described in reference to the watertubes D.

The steam-chamber C may either be made plain, cylindrical, or with corrugations between the tube groups, as shown at Fig. 7.

From What has been stated above it willbe seen that among other advantages the following most important ones will be obtained by my improved construction of water-tube boilers as compared with water-tube boilers of present construction.

First. A boiler constructed according to this invention for producing a certain steam power will be about two-thirds theweight of an ordinary water-tube boiler having the same steam-producing power, and it will occupy not more than two-thirds the space occupied by the latter. Thus a boiler of about nine feet nine inches height to the funnel and width of eight feet eight inches will contain two hundred and four tube groups (including feed-heater and superheater) with fourteen hundred and twenty-eight tubes of seveneig'nths of an inch diameter, and the steamtubes will give an effective steam-producing surface of seven hundred and fifty square feet, and the weight of the boiler charged with water will only be about ten tons.

Second. It will require only about one-ninth. the number of holes in the water and steam chambers, and consequently only about onesixth the number of joints.

Third. The joints are all out of reach of the fire or combustion-gases.

Fourth. Any tube group of any row can be removed and replaced in a very short space of time without disturbing the others, which is impossible with the ordinary constructions. This will also greatly facilitate the removal of scale, as on taking out a tube group and beating it with a hammer the scale will at once drop off.

Fifth. The boiler can be easily taken to pieces and transported to any locality where it can be rapidly set up and put to Work, no brickwork being required. Itis equally applicable as marine and land boilers.

Sixth. In ordinary water-tube boilers it is necessary to make the combustion-chamber Lastly,

very small and low in order not to occupy to much room with the enormous number of water-tubes required. With my improved construction, owing to the compact arrangement of the tubes, ample space can be given to the combustion-chamber, resulting in a much greater development of heat and more perfect combustion.

Seventh. Owing to the possibility of adapting scrapers to the tube groups, which is im-.

possible with ordinary boilers, they can always be kept free from soot and ashes, and thusthe tube-surface always be maintained in the most effective condition for taking up heat and raising steam.

Having thus described the nature of my.

invention, and in what manner the same is to be performed, I claim 1. In water tube boilers, the combination with two lower water chambers situated one on each side of the furnace grate, and a water and steam chamber above the grate, of groups of small water tubes connected at each end to a closed tapering cup or box formed of one piece, the large flat end being adapted to receive the said small tubes while the small end has a threaded neck for connection to the other parts of the boiler, the one such box having its neck passed through a hole in the said upper water and steam chamber and secured by a screw-nut on the inside, while the other cup or box is connected by its neck and a connecting tube to oneof the said lower water chambers of the boiler, there being several rows of such tube groups arranged on each sideof the furnace, substantiallyas described.

2. A compound water tube for water-tube boilers consisting of a group of tubes of small diameter connected at each end to cups or boxes formed of a single piece of a tapering shape, having at their large flat end a series of holes for the reception of the ends of the tubes, and at the small end a threaded tubular neck for connection to other parts of the boiler the reduced portions of the cup being fitted in tapered openings in the water and steam drum, and the threaded portion thereof being entirely inclosed within said drum, substantially as described.

3. A box or cup for a compound water tube, consisting of a tapering receptacle E formed of one piece and having a flat face at the larger end, with a series of holes adapted to receive the ends of the water tubes D and a threaded tubular extension at the smaller end, adapted to be secured to the water and steam chambers of the boiler the reduced portions of the cups being fitted in tapered openings in the boxes E E, of which the cups E are fixed by pipes F to the chambers B while the cups E are fixed directly to the chamber 0, there being several longitudinal rows of said compound tubes arranged one above the other, the reduced portions of the cups being fitted in tapered openings in the water and steam drum, and the threaded portion thereof being entirely inclosed within said drum substantially as described.

5. In water tube boilers, the combination with an upper water and steam chamber 0, and two lower water chambers B, of compound water tubes composed of a number of small tubes D fixed at each end in tapering cups or boxes E E of which the boxes E are fixed by tubes F to the chambers B while the boxes E are fixed to the chamber Oby having their screwed necks passed through holes in the chamber and secured by internal screw-nuts and washers, the coned surface of the boxes being made to fit water-tight into the coned holes in the chamber 0, and the threaded portions of the necks being entirely inclosed within said drum substantially as described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 8th day of November, A. D. 1894:.

ERNEST PETERSEN. Witnesses:

CHAS. D. ABEL, .1110. P. M. MILLAR'D.

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