US1729837A - Steam superheater - Google Patents

Description

Oct. 1, 1929; T. MART STEAM SUPERHEATER Filed Oct. 9, 1924 2 Sheets-Shpet l Oct. 1, 1929. 1,729,837

1.. T. MART STEAM SUPERHEATER Filed Oct. 9, 1924 2 Sheets-Sheet 2 Patented Oct. 1, 1929 UNITED STATES LEON T. MART, OF KANSAS CITY,

MISSOURI STEAM SUPERI-IEATER Application filed October 9, 1924. Serial My invention relates to steam superheaters, with particular reference to superheaters for use with return tubular boilers, or other shell boilers.

A purpose of my invention is to support a steam superheater upon the opposite side walls beneath an arch, shown in the drawings as the rear arch of a return tubular boiler.

A further purpose is to support an arch of a return tubular boiler upon the horizontally spaced headers of a superheater.

A further purpose is to avoid the use of return bends or castings within the fire zone.

A further purpose is to provide a superheater with an advantageous form of interchangeable headers.

A further purpose is to connect horizontally spaced headers having inlet and outlet re spectively of a superheater by a plurality of straight tubes through the heating zone and to internally baffle the headers to form a three-pass superheater unit in which the steam has to pass three times across the heating space between the inlet and outlet.

Further purposes will appear in the specification and in the claims. A

I have preferred to illustrate my invention in one main form only (with a slight modification) of the various forms it may take,

selecting a form that is inexpensive and effective in operation and which illustrates particularly well the principles involved.

Figure 1 is a perspective View illustrating the preferred form of superheater unit.

Figure 2 isa somewhat diagrammatic side elevation showing a return tubular boiler equipped with my superheater.

Figure 3 is a fragmentary section of Figure 2,.to enlarged scale, taken upon the line 33.

Figure 4 is a fragmentary top plan view of Figure 3.

Figure 5 is a fragmentary section of Figure 4 4L taken upon the line 55..

Figure 6 is a reducedperspective view of a slightly modified form.

In all figures like numerals refer to like parts.

Describing in illustration and not in limitation and referringto the drawings Prior to my invention steam superheaters for shell boilershave usually extended down through the rear archthat farther from the stackand into the relatively intense heat of the zone. Thus placed they have been subjected at the lower end to excessive temperathem. This also enables me to support the rear arch upon the horizontally spaced headers of the super-heater. The heating tubes are out of the way, not subjectto the too intense heat of the fire zone, and readily accessible for inspection or renewal. Thus installed the superheater makes it much easier to install and to maintain the rear arch.

The. superheater unit comprises horizontally spaced headers 6and 6 preferably alike and interchangeable They are connected by straight tubes 7, and each is provided with a flanged opening 8 for steam connection, the inlet for the piping shown being uponone side and the outlet upon the other of the top of the unit formed, the inlet in one header and the outlet in the other.

The headers, which may be of cast metal. are-shown as partitioned, as at 9 to make the unit three pass, that is to cause the steam to pass at high velocity three times through the heating zone of the (rear) flue 10.

In Figure 6 there is a slight modification in that inlet and outlet are from the same header. There is one partition in this header but none in the other, so as to make this a.

outside heating flue 15, rear uptake 10, fire tubes 16, stack uptake 17, stack 18, and main steam pipe 19. 1

The superheater unit horizontally span the rear flue 1O slightly beneath the flue cover or rear arch 20, one header, as 6, resting horizontally along the side wall 21 of the flue 10 and having flange connection at 22 with the steam pipe 19 from the boiler, and the other header, as 6, resting upon the opposite side wall 23 of the flue and discharging at any convenient point 24: into the superheated steam supply line 25. The superheating surfaces are provided by the tubes 7 between the headers.

The rear arch 20 is shown as comprising bricks or tiles 26 which are supported by transverse angles 27 and T 28 which angles and T are in turn supported at their ends by resting on the respective headers 6 and 6'.

It will be noted that all cast port-ions of the unit are placed outside the intense heat of the flue, the heating surface being straight lengths of worked metal in the form. of the pipes between the headers. This is an obvious advantage as they can stand intense heat well.

It will further be noted that the covered arch reflects heat upon the tubes which carry the steam so that without necessity for excessive heat at any point it is possible to obtain very uniform heat upon the bottom, top and sides of the tubes.

Steam materially expands during its passage through the superheater unit so that when the header units are alike the discharge velocity is considerably greater than the velocity of intake. For this reason it may sometimes be deemed preferable to forego the advantage of having the headers alike, proportioning the headers and connecting pipes to secure a more uniform velocity throughout the unit.

Likewise it may sometimes be deemed preferable to forego the advantage of the three pass arrangement obtained by providing a partition 9 in each header, and in this event these partitions may be dispensed with. While the three pass arrangement is desirable in that it gives more intense superheating it has also the disadvantage of giving more loss in pressure through the unit which under some conditions may make the single pass arrangement preferable.

In view of my invention and disclosure variations and modifications to ,meet individual whim or particular need to secure all or a part of the benefit of my invention are likely to become evident to others skilled in the art and I therefore claim all such in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. In a steam superheater and boiler unit, a fire tubular boiler, side walls forming a flue leading to the boiler tubes, a superheater comprising steam headers supported upon the side walls and steam tubes connected with the headers across the upper part of the flue, and roofing for the flue above the steam tubes and close to them.

2. In a steam superheater and boiler unit, a fire tubular boiler, side walls forming a flue leading to the boiler tubes, a superheater comprising steam headers supported upon the side walls and steam tubes connected with the headers across the upper part of the flue, and roofing for the flue supported upon "the headers and raised above the tubes to provide passage for flue gases about the steam tubes.

3. In a steam superheater and boiler unit, a hot flue having opposing walls, a pair of horizontally spaced steam headers in line with the walls, having the length of the headers horizontal and the long sides of the headers forming the tops and bottoms of the headers, pipes making counterconnection across the flue between the headers, an arch supported from the headers free from the pipes, steam inlet and outlet connection to the headers and a fire tube boiler arranged with its tubes in the immediate path of the hot gases passing the steam tubes.

4. In the equipment for a return tubular boiler, a flue at one end of the boiler opening into the tubes thereof and having opposing walls, a header upon each wall, pipes in the flue making a conduit unit with the headers, cover supports carried by the headers, a cover upon the supports free from the pipes, a steam inlet at one end of the unit and a steam outlet at the other end.

5. In a superheater for return tubular boilers, a flue at one end of the boiler, opening into the tubes thereof and having opposite I walls, a header upon each wall, a plurality of rows of pipes across from header to header and staggered, one row with respect to the other, arch-supports resting upon the headers above the pipes and an arch upon the supports giving room for circulation between and about the pipes.

6. A pair of sidewalls, steam superheater headers supported upon the sidewalls and having the lengths of the headers horizontal, pipes connecting the headers, flanged supports extending across the space between the walls and resting at their ends upon the headers and roofing for the space above the headers resting upon the flanges of the supports and giving room for circulation of hot gases between the pipes and the roofing.

LEON T. MART

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