US1590180A - Radiant superheater - Google Patents

Description

1 June 29 1926.

0/0 1 B I) 0 e in IL nIIIIIII/I/Vll/ll/ll/I/ 1 B BRQIDO RADIANT SUPERHEATER Filed March 15. 1923 v ea/yaw? Bro/0'0 INVENTOR #ns ATTORNEY BENJAMIN BBOIDQ, @F NEW YUIKK, It. 'Z., AGNQE lll THE SUPERHEATER it or a "roar, it. r.

Application area near. is, rare. Serial no. case n. i

This invention relates to super-heaters oil the type which has become known as the radiant type of superheaters. These superheaters are exposed to the direct radiant heat of the fuel bed and burning gases in the furnace and by far the biggest part of the heat given up to the superhcating sur face reaches it by direct radiation and only a comparatively small part is absorbed from the hot gases by convection. .This typeof superheater difiers materially in a number of respects from superheaters in which the main portion of the heat is delivered up to the superheater through convection and involves entirely new and dificult problems. Among them is the important one of protecting the superheater against a too intense heat of radiation.

The object of the present invention is to provide a novel and eficient way at protecting the superheater of the radiant type against heat which may prove too intense and which may endanger the lite oil the superheater elements.

The invention is illustrated in the accompanying sheet of drawings where Fig. l is a longitudinal vertical section through a water tnbe boiler in the fire box of which there is found a superheater protected by my novel device; line 2-2 0 Fig. l.

The boiler in connection with which ll illustrate my invention is of a usual type boilers of a great many diderent types. The

boiler illustrated comprises a setting 1 within which is located the furnace 2 'at the rear of which there is a bridge-Wall 3, the boiler proper being located above the furnace. Front and rear'water legs 4 and 5 respectively are connected by thewater tubes 6 and communicated at their upper ends with steam-and-water drum 7. Bag 8 directs the gases from furnace 2 over the water tubes 6 on their way to stack connection 9. Steam is taken 0d from the boiler at 10 and carried through the pipe ll either directly or through the superheater to the point of consumption. I

As far as described, this boiler is of an ordinary construction. The superheater to which I wish to apply my invention is associated with the rear wall 12 of the sett Fi 2 being a sectional view on the pipes 15 each have appropriately shaped ends to connect with these headers, the main portion of the pipes 15 lying within the setting and in close proximity to the wall. Steam is carried by pipe ll to the header l3 and is taken 0d from the header 14 at the point 16. The precise shape or construction of the pipes or elements 15 is iate-, rial as'far as my invention is concerned. For purposes of illustration 1 show them as consisting substantially of straight bare lengths but they might be covered with protecting covering or they might equally well have some ditferent shape. They might likewise, within the scope of the present invention, be parallel to the wall but at some angle to the vertical.

It will be noted that the superheater ele ments 15 are not struck directly by'any of the hot products of combustion trorn the furnace as these pass through the boiler to the stack but on the contrary derive practicall all of their heat from the fuel bed andv rom the hot gases by direct radiation only. The condition to which they are sub jected is severe and it has been found that even when supplied with a protective covering they are apt to deteriorate very rapidly. To interpose a screen or wall of any hind which would completely protect them against the radiant heat would defeat the a great deal of heat to the superheater elements.

propose to provide a series of water tubes 17 for this required rotection. water tubes 17 are genera ly shaped like the superheater elements 15, having a straight lengh and two bent ends, the latter coinlit tlll

llllll llll municating with the headers 18 and 19. The header '18 communicates by means of pipe 20 with the steam drum 7, while the header 19 is connected to the water leg 5 by the pipe 21. The lower header 19 is supplied with valved pipes 2222, so that accumulations of sediment can be blown off from time to time. The lengths of the water tubes 17 are alined in a plane somewhat closer to the furnace'than the superheater elements 15. It will be noted,-however, that they do not lie directly in front of the super heater elements but are arranged directly in front of the alternate spaces between the superheater elements. In this manner they do not shut ofi' to any appreciable extent the radiation from the furnace. The protection they afi'ord, however, is suflicient to insure prolonged life to the superheater elements. As above pointed out, bricks in a similar situation radiate a large amount of heat to the superheater elements, and the result is that their protection is considerably ofi'set. lVhile, of course, the water tubes 17 also radiate heat they are kept at comparativel low temperature by the water circulating through them and, therefore, will absorb much more of the heat radiated by the superheater elements than they in turn give out to the latter b their own radiation. The pipes 17 are fille with boiler water and are in effect a portion of the boiler system, and

a certain amount of steam will be enerated in them. This will circulate upwar through ipe 20 and reach the steam and water drum 7 ,new water being supplied to the lower drum by pipe 21.

While I show only one row of water tubes communicating with the boiler, and connect-' ed in a particular way to it by way of headers, I do not wish to be limited in these respects, as obviously other Wa s may be used.

The only essential is that t e tubes be arranged between the furnace and the superheater elements without cutting off the radiation of heat to the superheater elements.

It will be understood that where the superheater tubes are not vertical, the protective water tubes are arranged parallel to them, nearer to the furnace, and in line with the spaces between the superheater tubes, so that tection of the superheater elements princi pally, or almost entirely, on the difference in the rate at which the superheater elements and the water cooled tubes 17 radiate heat. I do not rely on these tubes for cooling gases coming into contact with them before reaching the superheater tubes as has been practiced heretofore.

What I claim is:

1-. In an apparatus of the class described, the combination of a furnace, a radiant type superheater comprising v parallel vertical alined superheater tubes adjacent to a wall of said furnace and water tubes parallel to the superheater tubes and in a plane parallel to and in advance of the plane of the superheater tubes, s'aid superheater tubes bein so located relatively tothe wateritubes an to the furnace that they are exposed to direct radiant heat from said furnace.

2. Inan apparatus of the class described, the combination of a furnace, a radiant t pe superheater comprising parallel vertical to the furnace that they are exposed to direct radiant heat from said furnace, upper and lower headers to which the water tubes are connected, and pipes connecting them to the steam and water space of the boiler.

3. In an apparatus of the class described,

the combination of a furnace, a radiant type superheater comprising parallel alined superheater tubes adjacent to a wall of said furnace and water tubes parallel to the superheater tubes and in a planeparallel to and in advance of the plane of the superheater tubes, said superheater tubes being so located relatively to the water tubes and to the furnace that they are exposed to direct radiant heat from said furnace.

BENJAMIN B R OIDO.

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