US1829919A - Boiler - Google Patents

Description

Nov. 3, 1931. w. H. ARMACOST BOILER.

Filed April 17. 1928- 3 Sheets-Sheet 1 Nov. 3, 1931; w. H. ARMACOST BOILER ril 17 M 2 TM N K 8 N T k, A a? r m M 3 W Q a 2 9 1 Filed Nov. 3, 1931.

w, H. ARMACOST v BOILER Filed April 17. 1928 5 Sheets-Sheet 3 INVENTOR. I

Myfiur A'rmacauf' A TTORNE Y.

Patented Nov. 3, 1931 UNITED STATES PATENT OFFICE wrrmm n. annmcosr, or NEW roman. Y., ASSIGZN'OR TO THE surnnnmrnn com PANY, orNEw YORK, N. Y.

BOILER Application filed April 17, 1928. Serial No. 270,664.

j This invention relates to water-tube boilers equipped with steam superheaters.

-It is correct theoretically, and has been found expedient in practice, to locate the steam superheater in a position such that the gases from the furnace come into contact with the superheating surface after they have passed over sufiicient boiler surface to remove enough of the heat so that the superheater will not be endangered, but to keep the superheater as close to the furnace as is consistent with this protective idea. In ortages mentioned above.

dina'ry boiler operation the output of the boiler will be variable but the location just described results in a substantially constant final temperature of the steam leaving the 'superheater even under great load variations. Superheaters placed at a point more remote from the ,furnace do not obtain such temperature uniformity. a

In boilers of the so-called horizontal watertube type, it has become quite customary to locate the superheater in what is called the interdeck position to obtain the advan- The boiler is, in other words, subdivided into two banks, a lower and an upper, the superheater being located between them. The lower bank is made relatively small in size, consisting of three to five rows of tubes which are exposed-to the furnace gases and'furnace radiation throughout their entire length. The upper bank is usually b'aflied to give three passes to the gases. The superheater is placed in the first of these passes in the free space between the two banks, or it is distributed throughout the free space between the two banks from ,front to rear of the boiler. I

This generalarrangement is good except for the fact that it results in a considerable amount of waste space within the boiler,

I making the setting for the entire boiler unnecessarily large and expensive. Other types of boilers, such as the Sterling type, are even" more objectionable on this score.

'It is the object of the present invention -to provide a boiler with an ideal space for longitudinal vertical section through a boiler of my design, Fig. 2 is a similar view of a somewhat modified form of the invention, and Fig. 3 is a similar view of a further modification.

Referring first to the form illustrated in Fig. 1, the furnace is shown at 1, the boiler proper being located above the furnace. The walls of the furnace 1 are surrounded on all sides by water screens. At the front, for example, the water tubes 2 and 3 connected to lower and upper headers 4 and 5 screen the wall 6 against the intense radiant heat of the furnace. Rear wall 7 is similarly screened by water tubes 8 andconnected to lower and uplimited in thisrespect, and a furnace using solid fuel and equipped for this purpose with the proper grate may be substituted.

The boiler proper is enclosed in the housing 13. Against the front and rear walls ofthis houslng are arranged the headers 14 and '15 which are preferably sectional but may be of the so-called box header type if desired. A bank of tubes 16 extending at the usual angle from front to back and comprisingthe proper number of rows of tubes connects these two headers. The'exact number of rows may vary from case to case, depending upon circumstances. While the bank is somewhat inclined to the horizontal, the usual practice of calling it a horizontal bank will be followed hereinafter.

Located about centrally above the bank 16 and at some distance above it is the drum 17. This is connected to the upper portion of headers 15 by the bank of tubes 18. The lower portions 19 of these tubes are straight, and parallel to the tubes 16 and are connected by bends to the vertical straight portions 20. The upper ends are bent toward and connected to the drum 17.

Front headers 14 extend vertically some distance above the bank of tubes 16 and their upper ends are connected to drum 17 by the circulators 21. The tubes making up the water screen 3 have their upperends connected to the lower ends of the headers 14.

The upper header 10 of the water screen 8 is connected at one or both ends by means of the riser or risers 22 and the pipes 23 to the drum 17. These risers 22 and pipes 23 preferably lie laterally entirely outside of the outline of the boiler, the drum 17 being extended beyond the setting at one or both ends, as required.

On the top of the bank of tubes 16 a horizontal baffle 24 extends from the rear headers 15 forward, stopping at the point 25 some distance from the front headers, from which point a vertical baflle 26 extends upward adjacent to the front of the tubes 18.

A vertical baffle 27 between baffle 26 and the rear wall of the housing extends from a point some distance above the baflie 24 upward. A short baflle 28 closes the space between this baffle and the drum 17.

The entire space between the front headers 14 and the baflle 26 is occupied by the superheater 29. This superheater comprises vertically arranged tubular loops connected to the two headers 30 and 31 lying outside of the setting of which 31 is connected by pipe 32 to the steam drum 17 and of which 30 delivers the superheated steam to the steam main (not shown). The straight portions of the tubular units connecting the looped structures to the headers extend through between the circulators 21. In the upper portion of the last pass is located the economizer 33.

Between the lowermost of the tubes 18 and the baffle 24 there is left just suflicient space for a soot pocket.

At the lower ends of the rear headers 15 is the sludge chamber 34 connected to the lower ends of the headers 15 by the connectors 35. Sludge is periodically blown off from this chamber in the usual manner.

The lower rear headers 9 are connected to the steam drum 17 at one or both sides by the downcomer or downcomers 36.

The form of the invention shown in Fig. 2 is substantially like that of Fig. 1. the prin cipal difference residing in the battling of the curved bank of tubes. The rear bank of tubes is divided into two portions separated by a space 37;. and the baffle 27 insteadof crossing the tubes lies entirely on the uppermost row of tubes 38 of the first portion of the bank. Convenient access is thus furnished for the maintenance of this baflle. A man can enter through the hole 39 and inspect and repair the baffle. Preferably two additional rows of tiles 40-4O extend from the baffle 27 to the rear bank in order to direct the gases out of the space 37 into the rear portion of the bank.

The baffle 26 is in this form shown as lying between the vertical portions of the two first rows of tubes of the upper bank;

In the form of the invention according to Fig. 3, the rear header 15 does not extend up far enough to have thelower ends of the upper bank 18 secured to it. Instead, a lower drum 41 is used, parallel to the upper drum 17 and adjacent to the header 15, to which it is connected by nipples 42. The tubes of the bank 18 are given the more conventional shape in this case of tubes extending between drums, although this is not essential. With the shape shown for these tubes the superheater space becomes more nearly triangular, and it will be found more convenient to give the superheater elements 29a the shape shown in the drawing and to have the headers 30a and 31a in front of the front wall of the setting. I

It will beseen' that the boiler provided by my invention has substantially every available cubic foot within the setting occupied by heat absorbing surfaces. By having the upper bank of tubes extend forward and upward and locating the drum 17 at a considerable height above the lowest point of the boiler, the difference in hydrostatic head of the portions of the boiler containing the heated water mixed with steam and the portion containing the water flowing downward from the drum is emphasized and the circulation within the boiler greatly promoted.

I claim:

1. In apparatus of the class described, the combination of vertical front and rear headers, a bank of horizontal water tubes connecting them, a transverse steam and water drum some distance above the bank and ap proximately midway between the headers, a

' second bank of water tubes connected to one" of the headers and extending toward the other header to a point under the drum and then upward toward the drum, a connection from the second header to the drum, asuperheater in the angular space formed by the two banks, a housing enclosing the boiler and superheater, and a connection from the said second bank comprisin straight lengths parallel to the first bank an vertical straight lengths, a bafiie comprising a portion extending above the first bank from the rear header to a point short of the front header and a vertical portion along the second bank and terminating short of the drum, a superheater abovethe first bank and forward of the vertical portion of the baflie, a housing enclosing the boiler and superheater, a connection from the front header to the drum, and a ifconnection from the drum to the superheater. 7

3. In apparatus of the class described, the combination of a boiler housing, a bank of substantially horizontal, straight water tubes extending from front to' back of the housing, a bank of curved water tubes above the first named bank distributed through the space from the rear wall to a point spaced from the front wall, said curved tubes having portions generallyparallel to the first bank, and generally vertical portions, and a superheater comprising tubular elements distributed through the space between said point and the front wall, a steamand water drumto which one end of all the tubes and the superheater are connected, and means interconneoting all the water tubes at their other ends. v

4. In apparatus of the class described, the combination of a boiler housing, a bank of substantially horizontal, straight water tubes -extending from front to back of the housing,

3 a bank of curved water tubes above the first named bank distributed through the space from the rear Wall to a point spaced from the front wall, said curved water tubes having portions generally parallel to the first 40 bank and generally vertical portions, said horizontal portions of the lowermost of the curved tubes being spaced only a small distance from thehorizontal bank, and a superheater comprising tubular elements distributed through the space between saidpoint and the front wall, whereby the entire space between the front and back of the housing is occupied by heat absorbing surfaces, a steam and water drum to which one end of all the water tubes and the superheater are connected, and means interconnecting all the water tubes at their other ends.

5. In apparatus of the class described, the

ends of all the tubes communicate, and a superheater distributed uniformly through the remaining portion of the space above the horizontal bank, said superheater being connected to said drum.

- 6. In apparatus of the class described, the combination of a boiler housing having front, rear, and side walls, a baffle extending from the rear wall forward to a point spaced from the front wall, a baffle extending upward from this point, a bank of substantlally horizontal water tubes below the horizontal baflle and extending from front to rear of the'housing, other water tubes arranged within the angle formed by-the two baffles and extending from the rear wall forward and upward, header means interconnecting the rear ends of allthe tubes, a steam and water drum with which the other ends of all of the tubes communicate, and a superheater arranged in the space between the upwardly extending bafiie and the front wall, said superheater being connected to said drum.

7. In apparatus of the class described, the combination of a boiler housing having front, rear and side walls, a steam and water drum at the top of the housing, water containing means adjacent to the rear wall below the drum, water tubes connecting the water containing means and the drum, said tubes being distributed throughout the space from side to side and from the back to a point spaced from the front wall, whereby a space is left extending from side to side and from the front to said point, header means adjacent to the front wall and above said water containing mean-s, a bank of water tubes connecting said header means and, said water containing means and distributed from side to side, connections to the drum from said header means, and a superheater distributed throughout said space above said bank of water tubes and connected to the header.

WILBUR H. ARMACOST.

to a point intermediate between the front and rear walls, header means'interconnecting the ends of the horizontal portions of'the curved bank and one set of ends of the horizontal bank of tubes, a drum with which the other

Images