US2072674A - Superheater - Google Patents

Description

M. HARD SUPERHEATER March 2, 1937.

Filed June 23, 1936 INVENTOR ATTORNEY Patented Mar. 2, 1937 UNITED STATES PATENT OFFICE SUPER/HEATER Application June 23, 1936, Serial No. 86,742

Claims.

The invention relates to superheaters for locomotive and similar boilers in which tubular superheating elements are located in boiler fiues, the two ends of each being secured to a header in 5 the smoke box.

In some forms of such tubular superheater elements it becomes important that the steam enter at one certain end of each element and leave at the other end and that the flow of he steam be not reversed. An illustration of such an element is found in United States Patent No. 1,996,134, granted on April 2, 1935, to A. Williams.

The object of the present invention is to provide means for positively insuring that the ele ments are not interchanged but are secured in their proper places so that the steam flow in each element occurs in the right direction.

The invention will be described in connection with the accompanying drawing in which Fig. 1 is a top view of a superheater header (with porvide means for posiively insuring that the elements in place and located in two flues which are shown in section; Fig. 2 is a sectional view on line 2--2 of Fig. 1; Fig. 3 is an enlarged view of some of the clamps and cooperating elements used to carry out the invention; and Fig. 4 is a section through one of the clamps and associated washers in position on the two ends of one of the elements.

The nature of the elements can readily be gathered from Figs. 1 and 2. Each element comprises a section I made up of an outer tube 3 and an inner tube 4 placed coaxially with each other and leaving an annular space 5 between them. With this annular space communicate two tubes 1 and 8, the former of which is directly connected to the header 9 and the latter of which is connected to a serpentine portion II of the element made up of four tube lengths connected in series by return bends, the last tube I3 of the series being extended through the interior of tube 4 and leading to the header 9.

This unit is the subject of the above-named United States Patent 1,996,134., where it is fully explained that the steam flow should be in such direction that steam from the header flows successively through the pipe I, the annular space of the section I, and the separate section II from which it is delivered back to the header. If the steam flow should be reversed, the full benefits of this type of unit will not be realized.

In Fig. 2 there is shown in section a standard form of superheater header and it is assumed that the reader is familiar with this header. The header is fully described and illustrated in numerous prior United States patents, for example,1,124,493. The point of interest in connection with the present invention is that the header comprises a series of chambers to alternate ones of which saturated steam is delivered from the boiler, the superheater units or elements, after having superheated the steam, delivering it back to the intervening chambers. In the particular example used for illustration the chambers marked with reference numeral I5 receive the saturated steam from the boiler and the superheater elements deliver the steam back in superheated condition to the chambers marked with reference numerals II.

The means for securing these superheater elements to the header are also well known and 15 broadly do not form a part of the invention. They comprise bolts I9 extending through openings 2| in the header walls separating chambers II from chambers I 5. These bolts extend through clamps 23 and carry nuts 25 on their lower ends. The element ends I and I3 carry washers 29 engaging the enlarged heads 2'! and resting on clamps 23. The washers 29 are forced by the clamps 23 against the heads 21 and thus force the latter into engagement with the header when the nuts 25 are drawn up. An inspection of Figs. 1 and 2 will show that the superheater elements are of two kinds-left and right. In Fig. 1, for example, there is shown a unit of one kind at the top and a unit of the opposite kind at the bottom. The two inlet ends I of the two units are adjacent to each other and in Fig. 2 it will be noted that they are connected to the first saturated chamber I5 from the left end. Each of the saturated chambers I 5 similarly has two ends of neighboring elements connected to it; and similarly each superheated steam chamber I I has two outlet ends I3 of adjacent elements connected to it. The two chambers I! at the two ends of the header form an exception, each having only one end I3 connected to it.

In the above, two elements have been specifically referred to which lie side by side and in the top'row of the fiues 3|. It will be understood of course that there are several horizontal rows of dues 3 I. In Fig. 2, to illustrate this, there are shown at the right a number of flues 3I constituting one vertical row of flues. Each flue has located in it a superheater element, the ends of the 2nd, 3rd, 4th, etc. row being brought forward of the ends I and I3 of the element illustrated and connected to the header at points successively further forward. This necessitates the use of a series of clamps 23 in a horizontal row extending forward from the flue as is the usual practice. In the particular example illustrated there are five rows of clamps since there are five horizontal rows of fiues. All of this is in accordance with the usual well-known practice. The location and dimensions of each element are such that a right hand unit could be placed where there should be a left hand unit and vice versa, and it is the object of the present invention to provide means whereby such misplace ment of the units can be positively prevented.

As a part of the means to prevent an interchange of left and right hand units the clamps 23 are placed on the elements in a permanent manner. This is done by having at least one end of each clamp equipped with an opening 33 through which the element end extends. In the form of clamp illustrated the other end is left open-ended as at 35, the two branches 3! and 39 forming a fork. This end could also be formed so as to present a circular opening 33, but it is unnecessary to do this at both ends and there are certain reasons of convenience why it is preferable to leave one end open as shown.

Reference to Fig. 4 will make clear that the enlarged head 21 cannot be slipped through the opening 33. In addition, it will be noted that the washer 29 on each branch is fixed permanently around its end 1 or E3. The washers and the clamps 23 are placed on the pipe ends during fabrication and once put in place are there permanently.

It will be noted, from an inspection of Fig. 3 particularly, that the branch 3'! is longer than the branch 39. This figure further shows on the opposite end of a clamp a projection 4| in line with the longer branch 31. The corner opposite it and 39 is clipped oiT or recessed as at 43.

The clamps on the left and right hand units are alike but are reversed in position. Thus in Figs. 1 and 3 the clamps in the top row have the long branches 31 and the projection 4! toward the left whereas the clamps in the second row have the projections 4i and the longer branch 31 of the fork at the right. The projections 4| of the clamps in the second row fit into the clipped or recessed corners of the clamps in the top row.

The clamps of the third row are in a position similar to that of the first row and their longer ends 31 fit into the spaces left by the shorter fiues of the clamps in the second row. Throughout, alternate rows are in relatively reversed position and no element can be used in any given place unless it has the right sort of clamp. It is obviously essential that in the fabrication care must be exercised to put the clamps in one position on the elements of one kind and in the opposite position on those of the other kind.

In order tomake sure that the clamps in the outer rows are of the correct kind there is used at each end a plate 45. This is conveniently secured in any preferred manner to the bracket 4! which carries the header. This plate 45 is equipped with projections 41 and recesses 49 so located as to lie respectively opposite the short and long branches of the fork of the outer row of clamps.

It will be clear that while one particular type of element has been referred to, the invention applies to other types where there are lefts and rights and that the above specific form of the invention described may in practice be modified without sacrificing its spirit and such variations are meant to fall within the scope of the appended claims.

What I claim is:

1. In a locomotive superheater of the type wherein tubular superheater elements located in horizontal rows of fiues have their ends secured to a header having a row of chambers from alternate ones of which steam is delivered to the elements, and to the intervening ones of which the elements deliver the steam after it is superheated, the elements being of two kinds, one being left and the other right, the steam inlet and outlet ends being reversed in one kind as compared with their order in the other kind, theelemen'ts of each horizontal row being so connected to the header that each chamber has two ends secured to it with the exception of each end chamber which each have only one end secured to it, means to prevent an element of the kind opposite that required being used in any given position, said means comprising clamps irremovably placed on said elements and all in the assembled structure lying in one plane, each clamp engaging the two ends of its element, a plate adjacent to each end of the row of clamps, the plates and clamps being so shaped that only an element of the right one of the two kinds fits into any given place.

2. Apparatus of the kind defined in claim 1,

the clamps all being alike and each'having a projection at each end laterally of a median longitudinal line through the clamp.

3. Apparatus of the kind defined in claim 1, the clamps all being alike and each having a projection at each end laterally of a median longitudinal line through the clamp, the clamps of one of said kinds of element being in a reversed position compared with those of the other kind.

4. Apparatus of the kind defined in claim 1, the clamps all being alike and each having a pro jection at each end laterally of a median longitudinal line through the clamp, the clamps on one of said kinds of element being in reversed position compared with those of the other kind, and the said plates being provided with recesses so located that only elements with the clamps in the right position can be placed adjacent to said plates.

5. Apparatus in accordance with claim 1, the clamps all being alike but those of one kind of element being reversed relatively to those of the other kind, each clamp having a greater over-all length at one side of the median line than at the other side of the median line.

MALCOLM HARD.

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