US1869967A - Desuperheater - Google Patents

Description

Aug. 2, 1932- s. M. JORGENSEN DESUPERHEATER Filed Nov. 21, 1929 3 Sheets-Sheet INVENTOR MJazgMfih 5%? L JVemZ BY ATTORNEY 1932- s. M. JORGENSEN 1,869,967

DESUPERHEATER Filed Nov. 21, 1929 5 Sheets-Sheet 2 O-OOO O O O O O O OOOOO XNVENTOR JWMM 7015mm ATTORN EY Aug. 2, 1932- s. M. JORGENSEN DESUPERHEATER Filed Nov. 2l, 1929 3 Sheets-Sheet 5 INVENTOR JVaMMforgmm BY d/w ATTORNEY Patented Aug. 2, 1932 UNITED" STATES PATENTl orries SVEND M. JOEGENSE-N, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE SUPERHEATEE COMPANY, OF NEW YORK, N. Y.

DESUPERHEATER Application filed November 21, 1929. Serial No. 408,768.

The present invention relates to the art of heat exchange and aims to provide a heat exchanger of the indirect type adapted for use as a desuperheater and which may be 1 manufactured at aminimum cost.

A common form of indirect type of heat exchanger used largely for desuperheating steam comprises a steam chest at its lower end having inlet and outlet chambers covered by a tube sheet into which are expanded the inlet and outlet ends of inverted U-t-ubes which extend upwardly and downwardly through a chamber containing water, the evaporation of which acts to desuperheat the superheated steam passing through the U- tubes between the chambers in the steam chest. An outlet connection is provided for carrying off the steam generated in the desuperheater. Desuperhea-ters of the type just described are quite satisfactory in many respects, but are somewhat expensive owing largely to the expense of expanding or otherwise fixing the tubes into the tube sheet and the costly steam chest fitting.

It is an object of my invention to design-a heat exchanger adapted for use as a desuper heater and in which the tube sheet may be dispensed with.

In accordance with my invention, the heat exchanger preferably comprises two chambers and U-tubes having their mouths at their upper ends for conducting the heating fluid from one chamber to the other and having their outer surfaces partially immersed in water or other liquid for absorbing heat from the fluid within the tubes.

The novel features of my invention will be pointed out in the appended claims. The invention itself, however, together with further objects and advantages, will best be understood from a detailed description of a desuperheater embodying my invention and such a description will now be given in connection with the accompanying drawings in which I Fig. 1 is a central vertical section of the desuperheater in accordance with my invention- Fi s. 2 and-3 are horizontal sectional 7 13 views through the apparatus of Fig. 1, Fig.

2 being taken on the line 22 of Fig. 1 and The desuperheater illustrated in Figs. 1, 2

and 3 comprises a cylindrical shell 10 having its axis vertical and having a central partition 12 running downwardly from its top. Partition 12 forms chambers 14, 16 within the shell 10, the chamber 1 1 being shown as having an inlet 18 and chamber 16 as having an outlet 20. Inlet 18 and outlet 20 preferably are near the upper end of the shell, and a tube'bundle composed of U-tubes 22 is arranged. within the shell so that the mouths of tubes 22 face upwardly and so" that the steam to be desuperheated is conveyed through the tubes from the upper portion of chamber 14 around the lower edge of partition 12 to the upper portion of chamber 16, each of the. tubes 22 having its legs on opposite sides of the partition 12 for this purpose and means being provided to preventpassage of steam from chamber 14 to chamber 16 except through the tubes 22. The chambers 14 and 16 contain a body of water 17 surrounding tubes 22 for absorbing the excess heat of the steam admitted through inlet 18, and the body of water in the shell 10 provided for this purpose will ordinarily extend considerably above the lower edge of partition 12 and will therefore act in cooperation with the partition to separate chambers 1a and 16 from each other to prevent passage of steam from one to the other except through tubes 22. As willbe explained more in detail herein below, conditions may arise in .the operation of the desuperheater which make it advisable to provide means in addition :to the body of liquid for separating chambers 14 and 16. In the arrangement illustrated, such additional separating means is provided in connectionwith the means for holding the tubes 22 in place within the shell 10.

The tube holding means is shown as having upper and lower sections, the lower section comprising beams 24, each having wide horizontal flanges 24a at the top and bottom on one side, forming a channel section, and having a narrow horizontal flange 24?) on other side but at the top only. The purpose of flanges 246 will be pointed out hereinbelow. Beams 24 are arranged in pairs with their wide flanges facing and beams 26 of less height and of l. section are placed intermediate the pairs of beams 24, the bottoms of the two sets of beams being shown as at the same level. Beams 26 are also arranged in pairs with their horizontal flanges 26a facing and each pair of beams, both of the channel type and L type, have their horizontal flanges recessed or notched as a l 25 to receive the legs of tubes 22. Two rows of U-tubes 22 are engaged by each pair of beams 24 and each pair 26, and the notches 25 are staggered in one beam with respect to those in the other beam of the same pair so that edges of the flanges may press against the sides of the tubes to clamp them firmly in the recesses 25 and the beams of each pair are drawn together strongly by bolts 27 so as to clamp the tubes firmly enough to support their weight. Each bolt 27 is threaded at one end into the Vertical flange oil a beam or 26 and has its head counter-sunk into the vertical flange of the other beam of the same pair. The threaded counter-sunk arrangement of the bolts is adapted to permit the pair of beams 26 to substantially till the space between the beams 24 as is shown in Fig. In assembling the apparatus, each pair of beams 24 with the two rows of tubes 22 belonging therewith are assembled and the necessary bolts 27 screwed into place in the beams 24 before the beams and tubes are assembled in the shell 10. Each pair of beams 26 and its associated tubes are likewise assembled before being placed in shell 10. Beams 24 and 26 extend across the shell 10 beneath the wall 12 and are supported by washers 28 held up by nuts 29 on the lower ends of bolts 30 and 30a. Bolts 30 run up into and are held in a flange 31 fixed to shell 10 near its lower end and bolts 30a run up into and are held in a bar 32 fixed to the lower end of wall 12. At their upper ends the tubes 22 are supported against lateral movement by recessed channels 24 arranged in pairs and clamped to the tubes 22 in the manner described in connection with channel beams 24. The pairs of channels 24 are held at their ends by U- shaped guides 36 welded or otherwise tastened to the inside of the shell and to opposite faces of the wall 12. As the guides 36 embrace the ends'of thechannels 24, there is not room to place adjacent pairs of channels 24 and their guides 86 in the same horizontal plane. Alternate pairs of channels .24 are therefore placed in a lower plane than the others as appears in Fig. 1.

In order that liquid in chambers 14 and 16 may not surge from one to the other if pressure diiterences exist between them, the partition formed by wall 12 may be extended to the edge of shell 10 by putting packing 34 between beams 24 and 26 on one side of wall 12. Rubber packing preferred for this purpose and is compress d tightly between each pair of beams 24 and when the beams are drawn together by the bolts 27, so that liquid cannot pass between the beams of a given pair, and owing to beams 26 being of less heigh than beams 24, the packing 34 is compressed at between the horizontal flanges 24b of beams 24 and the upper edges of the vertical flanges of beams 26 so that liquid cannot pass along the joint between a pair of beams 24 and a pair 26. team formed in chambers 14 and 16 can pass up between beams 24 and 26 except where the packing 84 is used. Ample space exists, of

course, for the passage of steam around and between channels 24.

If desired, the wall. 1 may be extended to the bottom of the shell 10, the modifications necessary in th details of the apparatus when the wall 12 is so extended being obvious.

It will be understood that in operation the liquid level in the chambers 14 and 16 is varied to change the degree of desuperheating accomplished as desired, the heat ab-t stracted from the superheated steam acting to vaporize liquid in chambers 14 and 16 which rises in the chambers. The vapor produced in chamber 14 mixes with the superheated steam and passes with it into the inlet ends of the U-tubes, and the vapor produced in chamber 16 mixes with the steam flowing from the outlets of the U-tubes and passes with it through the outlet 20. hen uniform conditions of operation have been' established, there is very little difference in pressure between chambers 14 and 16. l-Iowever, in putting the desuperheater into operation, assuming the apparatus to be cold, a material difference of pressure between the two chambers may be developed for the reason that the tubes 22 are not drainablc and when the steam is first turned into them it condenses, forming water which closes the tubes against the passage of steam. Such water has to be blown out by the steam and at this time the ditlerence of pressure between the two chambers might be suflicient to force the water in the shell over into the steam line. Such action, however, is substantially prevented by the partition formed by wall 12, beams 24 and 26 and the packing 34 therebetween.

A pipe 38 for supplying water for desuperheating purposes to the chambers 14 and 16 is shown. The pipe 38 is connected into the shell 10 on opposite sides of the vertical wall 12 by branch s S9 and 39a. In order that a difference of pressure on opposite sides of "all 12 may not force liquid through the branches 3% and 39 and perhaps carry water into the steam line, a check valve 40 is preferably provided in the branch 39 connecting with the inlet chamber 14;

Whereas in the desuperheater above described, the chambers 14 and 16 are complete'ly separated by a partition, it will be noted that, by careful operation, the necessity for the portion of the partition formed by beams 24, 26 and packing 34, or its equivalent, may be dispensed with and the liquid in the lower end of the shell '10 be depended upon, in conjunction with a partition wall such as 12, to separate the two chambers 14 and 16. When the liquid is thus depended on to act as part of the partition between the two chambers, the desuperheater and the liquid therein should be brought up substantially to the temperature of the outlet steam line before the superheated steam is passed through the apparatus. 7

As shown, the shell 10 is closed at its lower end by a dished bottom plate 10a and has at its top two manholes and their usual manhole covers 42 and 44 to provide access to the interior of the chambers 14 and 16.

It will be apparent that a heat exchanger in accordance with my invention not only dispenses with a tube sheet but also eliminatesthe steam chest and the outside connection for taking OK the steam generated in the device as well as the necessity for rolling or otherwise fixing the tubes in the tube sheet.

I claim:

1. In a des'uperheater, the combination of two vertically extending chambers therein, one having an inlet and the other an outlet, U-tubes having their mouths facing upwardly for conducting heating fluid from one chamber to the other, and liquid in said chambers in heat absorbing contact with said tubes below their mouths and of the same character in each.

2. In apparatus as set forth in claim 1, positioning means for the tubes in the upper portions of the chambers having spaces therein for the free passage of vapor.

3. In apparatus as set forth in claim 1, positioning means for the tubes in the upper portions of the chambers having spaces there in for the free passage of vapor and supporting means engaging the tubes relatively near their bends.

4. In a desuperheater, the combination of a shell having a vertically extending partition and having an inlet and outlet on opposite sides of said partition, U-tubes for conducting heating fluid around the lower end of said partition, said shell adapted to contain liquid in contact with said tubes, supporting means engaging the tubes relatively near their bends, and means associated with said supporting means and acting with said partition to prevent passage of liquid from one side of said partition to the other.

to be desuperheated from one chamber to the other and one chamber having an inlet and the other an outlet, said chambers adapted to contain liquid in heat absorbing contact with said tubes below their mouths, a branched pipe for supplying liquid to said chambers t and a check valve in the branch leading into the chamber having the inlet.

6. In an apparatus for interchanging heat between a liquid and a gaseous fluid, the combination with two chambers andu-tubes extending through and between said chambers for conducting the gaseous fluid during the heat exchange, means for positioning said tubes comprisingchannel shaped members having notched flanges for clamping said tubes, and guides for said members fixed to the wall of said chambers. I

7. In an apparatus for interchanging heat between a liquid and a gaseous fluid, the combination with two chambers and U-tubes extending through and between said chambers for conducting the gaseous fluid during the heat exchange, of supporting means for said tubes comprising channel shaped members having notched flanges for clamping said tubes.

8. In an apparatus for interchanging heat between a liquid and a gaseous fluid, the combination of two chambers and U-tubes extending through and between said chambers for conveying the gaseous fluid during the heat exchange, said chambers adapted to contain liquid in contact with said tubes, sup porting means for said tubes and packing means carried by said supporting means and forming therewith a means for preventing said liquid from passing from one of said chambers to the other.

9. In a heat exchange apparatus, the combination with two chambers of U-tubes therein and running from one chamber to the other, and positioning means for said tubes acting in part also as means for separating said chambers and including channel beams having notched flanges arranged in pairs with the channel forming flanges of the beams in a given pair facing each other and clamped to the legs of a set of said tubes, said channel beams each having a narrow flange along one edge only, L-shaped beams also arranged in pairs and having notched flanges in facing arrangement, said L-shaped beams being intermediate said channel beams and clamped to the legs of other sets of said tubes, and packing between the beams of each pair,

said packing having portions compressed between said narrow flanges and edges of the L-shaped beams to seal the joints between the beams of different section.

10. The combination in a steam desuperheater of a shell having two chambers there in and having an inlet and an outlet near its upper end, a set of U-tubes in said shell having their mouths opening upwardly in the upper portions of said chambers, and a body of liquid in said shell arranged to separate said chambers.

11. The combination with a shell having a partition extending from its top downwardly and having an inlet on one side of said partition and an outlet on the other, of a set of U-tubes having their mouths opening upwardly in said chambers and lying on opposite sides of said partition, said shell adapted 15 to contain water on both sides of said partition and below the mouths of said tubes.

12. The combination with a shell adapted to contain two bodies of water and having an inlet above the normal level of one body and an outlet above the normal level or 1,116 other body, of a set of U-tubes therein having their mouths opening upwardly in said chambers and each of said tubes having one inouth above the normal level of one of said bodies 25 and one above the normal level of the other of said bodies.

SVEND M. JORGENSEN.

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