Патент USA US2106589код для вставки
Jan. 25, 1938. T. yw. BIGGER ET AL BOILER DRUM Filed l_July 22, 193e \. 2,106,589 ' 2,106,589 Patented Jan. 25, 1938 UNITED STATES PATENT oFFlcE ' 2,106,589 BOILER DRUM Trafford W. Bigger and’ Frank L.l Hargrova» Schenectady, N. Y., assignors to General Elec tric Company, a corporation of New York Application July z2, 1936, serial No. 91,946. 1 Claim. (Cl. 183--83) The present invention relates to boiler drums for receiving heated liquid or liquid and vapor mixtures and eüecting partial conversion of the portion I2. To this end it is connected to cham bersv I4 and I5 formingparts of a level-indicating device, not shown, the level being normallyl main tained at a point intermediate the connections to the Achambers I4 and. I5. 'I’he dome I0 is se- 5 cured to the intermediate portion Il by a weld I6, and ' the intermediate portion Il and the> -lower portion I2 are united by .another w'eld I1. The dome Il). has a central opening closed by ments. The liquid is discharged from such heat- ` means of a ring I8 secured to the dome by a weld 10 ing elements into a drum at reduced pressure I3 and a cylinder member 28 disposed within the whereby it is at least partly converted into vapor, ring I8 and secured thereto at its upper end by a the vapor being discharged from the drum to a weld 2|. The cylinder20 has a flanged bottom 22 engaging the lower end of the sleeve I8. This consumer and the remaining liquid being recir - arrangement permits access to the interior of the 15 culated through the heating elements. The object, of the invention ,is to providel an drum for the purpose of inspection after removal improved construction of boiler drums of the type of the weld 2| and lowering of the cylinder mem above specified to attain a better separation of ber 20. e During lowering, the cylinder member 20 liquid from vapor. Complete separation of liquid may be -held by means including a handle 23 se particles from the vapor to be discharged from cured to the interior of the member 20. ' The .p20 the drum is important, especially in connection liquid to be converted into vapor is conducted to the drum by means of two conduits 24 and with boilers such as mercury boilers using op erating liquids other than water because liquid 25 connected to diametrically opposite points of particles entrained in the vapor are injurious the dome. The liquid thus conducted to the dome is received by an annular inlet chamber> 23 hav- -`25 when impinging on machine elements, for in ing an outerwall formed by two curved sheets or stance the blading of a _mercury vapor turbine. For a consideration of what we believe to be Walls 21 and 28 secured to the drum by welds 23 novel and our invention, attention is directed to and 30 respectively. Thev chamber 26 has an liquid into vapor and separation of the vapor thus 5 formed 'from the remaining liquid. Such drums are used in connection with forced circulation and flash-type boilers in which liquid is heated within heating elements at pressures high enough to prevent evaporation of the liquid within these eie 10 15 v2() 25 the following description and the claim append 30 ed thereto in connection with the accompanying drawing.' ~ ' In the drawing, Fig. 1 represents a front view of a mercury boiler drum embodying our inven tion; Fig. 2 is a. section along the line 2-2 of 35 Fig. l; and Fig. 3 is a section alongthe line 3_3 oi’ Fig. 2.- ’ . _ ‘ The mercury boiler drum comprises an outer body having an upper portion or dome Ill, an intermediate cylindrical portion Il and a lower «i0 portion I2. The upper portion I0 is larger in inner cylindrical wall 3l connected to the' outer wall 21, 28 by a top 32 and a bottom 33._ The v30 bottom 33 includes an annular row of partitions 34 forming a plurality of nozzles 35 through which _liquid'is discharged from the chamber 26 into the space deiined by the intermediate drum _ portion II. VThe conduits 24, 25 discharge tan- 35 . gentially towards the inner surfaces of the curved sheets 21 and 28 so that the liquid discharged from the conduits assumes at once a circular path within the chamber 26. The outer edges of the partitions 34 are spaced from the inner 40 surfaces of the curved walls 21 and 28 of the inlet diameter than the intermediate portion Il, whereas the.lower portion I2 is considerably `_chamber 26 to form a continuousspace 34a for receiving liquid from the inlet conduits 24 and 25 smaller in diameter-than the intermediate por tion. In the present example the lower portion and for facilitating distribution of theliquid to 45 has a diameter of the order of about one-half of the nozzles 35. The body oi' liquid contained in 45 the diameter of the intermediate portion II and said space 34a also acts as a cushion-to absorb the lower end of the lower portion I2, is tapered'. some of the impact energy of theliquid entering' ’ downward, ending in a conduit connection I3 . the chamber through the- inlet conduits 24 and from which liquid is discharged from the drum 25. The liquid .is discharged from the chamber _50 and conducted to a heating element, not shown. 28, as stated above, through the row of nozzles 50 The small diameterand the tapering of the lower 35 which _are ‘arranged so as >to cause tl‘e'liquidv portion. I2, reduce the liquid space therein to a‘ 'to follow a helical path downward alongthe> minimum. This is desirable in mercury boilers ~ inner surface of the intermediate portion I I. The due to the high cost of mercury. ',A- definite liq - length of the helical path is- preferably a multiple 55 uid level is normally maintained _in the lower of 360l angular degrees.- The-'liquid is at least 5_5 2,106,589 . partly evaporated on its path through the inter ' impact of the liquid on the blade portions 5I. mediate portion I I. The greater inertia of the The lower portions of the blades 46 are vertical. liquid and the action of centrifugal force acting Thus, the first row of blades changes the spiral thereon cause the liquid to form a spinning cy paths of the liquid into a vertical, downwardly lindrical sheath or boundary layer on the surface directed path. The blades 41 and 48 are -vertically 5 of the intermediate portion II. thereby forcing arranged to further straighten and quiet the flow the vapor inward, that is, towards the central so that liquid discharged from the lower ends be portion of the space within the intermediate tween the blades 46 is forced upward in a vertical drum portion I I, whence the vapor is discharged path defined between the blades 41, whence it is 10 in the direction of the arrows 36a through -the discharged therefrom to flow downwardthrough 10 opening 36 defined by the inner surface ci the the vertical passages defined between adjacent wall 3|. The vapor is conducted to a consumer, blades 48. Thus, the three rows of blades form not shown, by a conduit _31 secured to the dome a zig-zag path through which the liquid flows on IIJ by a weld 3B and communicating with a space its passage from the intermediate drum to the 15 within the dome through an opening 39 in an pool in the lower drum portion I2. The zig-zag 15 upper end. portion of the conduit 31. Liquid par path is of considerable length and thereby ticles remaining entrained in the vapor are sub straightens and quiets the flow of the liquid, caus stantially removed in the dome I0 as such par ing the liquid to flow gently into the pool’with ticles impinge on the surface of the drum. This in the lower drum portion I2 without causing 20 liquid is collected within grooves 40 and 4I de therein substantial disturbances of the level. The 20 fined between the wall of the drum and the curved lower drum portion I2 is also connected to a con sheets 21 and 2t. These grooves communicate duit 53 through which liquid may be conducted with the lower drum portion I2 by conduits 42 to the drum, for instance, from a mercury con and 43 respectively. The provision of a separate denser, not shown. 25 path for conducting liquid from the dome III to ‘ Having described the method of operation of 25 the lower drum portion I2 is important in that it our invention, together with the apparatus which prevents liquid once separated from the vapor we now consider to represent the best embodi in the dome from againvbecoming mixed with the ment thereof, we desire to have it understood vapor. To this end, ring member 3l has an upper 30 projection 44 so that any liquid dropping onto that the apparatus shown is only illustrative and 30 that the invention may be'carried out by other the top of the chamber 26 is prevented from flow means. ing into the opening 36 and becoming entrained in the vapor flowing therethrough. To the same end, the flanged bottom 22 of the cylinder mem 35 ber 20 is provided with a cone-shaped surface 5. Liquid particles entrained in the vapor and im pinging the surface 45 are deflected laterally to be collected in the grooves 40 and 4I. In order to permit proper level control in the 40 lower portion I2 it is desirable to maintain a quiet liquid pool therein. Such quiet pool also assures proper level-indication. This is accom . plished in accordance with our invention by the provision of means for destroying the velocity energy of the liquid in the lower space of the in termediate drum portion II and directing the liquid in a smooth.. gentle path into the lower drum portion I2. These means form a zig-zag path for the liquid and as' shown in the present What we claim as new and desire to secure by Letters Patent of the United States is: A boiler drum including the combination of a cylindrically lshaped vertically disposed drum 35 having an upper portion, an intermediate portion and a lower portion, the diameter of the inter mediate portion being smaller than that of the upper but considerably larger than that of the lower portion, an annular chamber formed with in and supported on the upper portion, conduit means for conducting heated liquid to the cham ber, the chamber having a bottom with a ring of nozzles for discharging ñuid into the interme diate portion and for causing the fluid to flow in a helical path along the surface of the inter mediate portion whereby the liquid by the action of centrifugal force is forced outward forming a layer on the surface of the intermediate portion and causing the vapor to be forced radially in ward, means including a vapor discharge conduit 50 instance comprise three rows of blades 46, 41, and 46. The last row of blades 4I is disposed within the upper end of the lower drum portion I2 connected to the upper drum portion and a cen which upper end projects into the lower end of tral opening formed by the annular chamber for the intermediate drum portion II. 'I'he inner conducting vapor from the intermediate portion 55 edges of the blades 4l are secured to a pipe 49 through the upper portion to a consumer, means which acts asV a stiifener for the blades and ' disposed in the lower end of the intermediate por also as a vent, permitting vapor to be conducted tion and including an extension of the lower from the lower drum portion I2 to the interme portion projecting into the intermediate portion diate drum portion I I. The second row of blades and a plurality of rows of blades for directing the 41 is disposed between the outer surface of the liquid in a vertical path into the lower portion, extension-of the lower drumv portion I2 and the and means for conducting liquid particles sepa inner surface of a cylindrical element 5l. The rated from the vapor in the upper portion into first row of blades 46 is located between the outer the lower ‘portion comprising grooves formed be surface of the cylindrical element 6l and the .inner surface of the intermediate drum portion II. The upper portions II of the first row of blades 46 are bent in the direction of-fiow >of liquid. as indicated by arrows l2, to reduce the tween the chamber and the wall of ‘the upper portion and conduits between the grooves and the lower portion. TRAFFORD W. BIGGER. FRANK L. HARGROV'E.