US1558344A

US1558344A - Baffling for boilers

Info

Publication number: US1558344A
Application number: US670489A
Authority: US
Inventors: Joseph B Crane
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-10-24
Filing date: 1923-10-24
Publication date: 1925-10-20
Anticipated expiration: 1942-10-20

Description

J. B. CRANE BAFFLING FOR"BOILERS 1923 3 Sheets-Sheet 2 Filed Oct. 24

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J. B. CRANE BAFFLING FOR BOILERS Filed Oct. 24. 1923 s Sheets-Shet s Ell Patented Oct. 20, 1925.

UNITED STATES PATENT OFFICE.

JOSEPH B. CRANE, 0]! PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO GEORGE '1. LADD,

OI PITTSBURGH, PENNSYLVANIA.

BAI'FLING FOB BOILERS.

Application filed October 24, 1923. Serial No. 670,489.

To all whom it may concern:

Be it known that I, JOSEPH B. CRANE, residing at Pittsburgh, in the county of Allegheny and State ofPennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in Baffling for Boilers, of which ima' provements the following is a specification.

It is the usual practice to so construct and arrange the baflies in boilers that the direction of flow of gases through the boiler is reversed or changed through an angle of approximately one hundred and eighty degrees, twov or three times. This reversal causes a greater retardation in the rate of flow than the tubes themselves, and hence in constructing a boiler provision must be made either by the construction of the stack or the employment of exhaust fans for producing a sufficient drop of pressure between the furnace and the gases outlet, to overcome not only the retardation due to the resistance encountered by the ases flowing across and along the tubes and that due to the reversal of the flow when operating at normal rating, but also to cause the increased flow necessary to operate the boiler above rating. The construction of a stack capable of overcoming the necessary drop of pressure orthe employment of a fan of suficient capacity, adds greatly to the cost .of installation. It is of course possible to obtain an increase of rating without increasing the volume or weight of gases flowing through the boiler, by increasing the temperature of the gases generated. This method is decidedly objectionable as it involves a :great increase in the amount of fuel consumed, and a consequent increase in operating expenses.

The invention described herein has for its object the so baffling of the boiler that eiiicient contact of the hot gases with the heat ing surfaces is attained without reversal in the direction of flow of the gases, and with slight change in the direction of flow. The invention is hereinafter more fully described and claimed.

. In the accompanying drawings forming apart of this specification Fig. 1 is a sectional elevation of 'a vertical water tube boiler baflied as described andclaimed herein; Fig. 2 is a sectional planview on a plane indicated by the line IIII Fig. 1; Figs. 3, 4:, 5, and 6 are detail views showing different arrangments of battles and manner of constructing the same.

In combining the improvenwnt claimed herein with vertical Water tube boilers, the

bafflesextend from the lower to the upper drums or the entire length of the tubes, and parallel therewith. In the embodiment of the invention shown herein in Fig. 1, the battles are arranged in line with the last series of tubes forming the several banks of

tubes

1, 2, 3,but theinvention claimed herein is not limited to any specific location of the baflies transverse of the direction of flow of the gases from the combustion chamber to the stack. To permit of the-flow of gases to the stack, opening or ports 4 are formed through the baiiies. As is Well known to those skilled in the art, a boiler is at times operated at normal rating and frequently considerably above normal rating, and when operated above rating the volume of gases generated and passed through the boiler is very much greater than when the boiler is operated at normal rating. Hence the openngs 4 through the first baffle or the one ad- ]acent to the combustion chamber, are made of such dimensions as to. permit the passage of gases which would be generated when the boi er is operated at an average rating be tween normal and the highest rating at which the boiler is designed to be operated. In order to break up the streams of gases flowing through the openings in a battle, and so divert'such streams as to ensure the circulation ofthe gases among the tubes the openings in succeeding baffles are'arranged out of alinement with the openings the preceding baffie. As for example,'in the embodiment shown in Figs. 1 and 2, the openings in the second baffle are arranged out of alinement with the openings in the first battle, and the openings in the third are arranged out of alinement with the openings in the second bafie. i

As the gases flowing between the tubes are progressively cooled and their volumes decreased, the total area of the openings in each succeeding baffle are preferably proportionally less than that of the openings in the preceding baflle. In vertical boilers, and in the term vertical boilers are included both the Wicks Sterling and the Ladd or Milne types, the fuel bed i's adjacent to the lower ends of the first bank of tubes, as shown in Fig. 1, andjin order to prevent a tendency of the gases to short circuit through the lower openings in the batlle, such openings may be made of relatively small areas and the areas profrirssively larger towards the upper ends ot' the battles. This proportioning of the areas of the openings in connection with the tendency of the hot gases to pass upward. would tend to draw the gases away from the smaller openings of the lower end, but as the openings at the upper ends will permit of the passage of only certain proportions ofthe volumes generated, there will always be an etficient flow oi gases through the lower openings. Such a construction of bullies and relative proportioning of openings in each will ensure a substantially unitorm flow of gases and consequently equal application of heat in all points along the length of the tubes in front of such baflle.

As shown in Figs. 3 and ti, the bafiies may be formed by filling the spaces between alternate pairs of tubes with suitable material such tor example as wedge shaped blocks 5, as shown in Fig. (3. In such a construction the openings for the passage of gases will extend the entire distance be-- tween'the drums. But as in such construction it may be ditlicult to control the distribution of the gases vertically, it is p re-' ferred to construct the battles as shown in Fig. As shown thereon, the spaces between all of the tubes; oi a row or series are so lilledor closed as to have openings at suitable intervals horizontally and vertirally. A desirable means for forming sucla a baille consists in employing wedge shapec blocks (3. These blocks are formed with grooves in one edge so as to fit around the tubes while the opposite edge is inclined. These blocks are so coii'structed that when placed in reversed position with their inclined faces in contact and their ends in alinement, the combined width of the blocks will be greater than the distance between walls of ad iacent tubes. In arranging these blocks in position, a block is inserted between adjacent tubes with its larger end resting on the lower drum and the groove in its edge engaging a tube. A. second block in reversed position is then inserted between the first block and the other tube, but as the combined widths of the blocks is greater than the distance between the tubes, this second tube will not move down so that its lower end will bear on the drum,'hence there will be an opening. formed. The third block 6 will be arranged so that its larger end will rest on the larger end of the block 6" and the block 6 inserted in the same manner as the block 6*, thereby forming an opening of double the area of the opening at the lower end of the block 6. By thus forming the battle, a plurality of openings are formed alternating horizontally and vertically. In case smaller openings are desired, the blocks forming the battle may be arranged as shown in F 4. As shown in Fig. 5, one of the members as 7 forming a pair of blocks may be made shorter than the mem her 6. a

It is characteristic of the improvement claimed herein that although the general direction of flow of gases from the combustion chamber to the stack is at right angles to the tubes forming the heating surfaces, their lines of movement are more or less directed from straight lines by the relative positions of the openings in the baflles, and hence their flow may be more correctly termed sinuous but in no case Will the lateral diversion from the general line of flow approach a reversal of the direction of flow.

I claim herein as my invention:

' 1. A vertical water tube boiler having in combination vertical banks of tubes, a combustion chamber and an outlet for gases so arranged on opposite sides of the banks of tubes that the line of flow of hot gases will be at an angle to the tubes and baflles extendin parallel with and the entire Widths of the banks of tubes and having openings therethrough the openings in adjacent baffles being out of alinement and the area of said openings increasing from points adjacent to the combustion chamber. I

2. A vertical water tube boiler having in combination therewith vertical banks 0:" tubes, combustionchamber and an outlet for the gases so arranged on opposite sides of the bank of tubes that a line of flow of the gases will be at an angle to the tubes, and. battles consisting of a plurality of pairs of longitudinally tapering blocks arranged between adjacent tubes, a block of each pair being spaced from the vertically alined block on the adjacent pair.

In testimony whereof, I have hereunto set my hand.

JOSEPH B. CRANE.