US2162871A - Condenser - Google Patents

Description

June 20, 1939. c. B. TULEY ET AL CONDENSER Filed April 6, I938 INVENTORS f-Zv-uuu-zs B Tin-er m Jenn w. MgNuL-rr. a. 15, M ATTORNEY Patented June 20, 1939 UNITED STATES CONDENSER Charles B. Tuley, Glenolden, and John W. Mc- Nulty, Ridley Park, Pa., assignors to Westinghouse Electric & Manufacturing Company,

East Pittsburgh, Pa. sylvania a corporation of Penn- Application April 6, 1938, Serial No, 200,344

3 Claims.

Our invention relates to surface condensers of the multiple-pass type and it has for an object to provide apparatus of this character wherein the tubes of the respective passes are disposed in such manner that the tubes of the first pass are more widely spaced than the tubes of the second or subsequent passes.

It has been customary, in laying out tube sheets for two or multiple pass condensers, to pitch the tubes closer together in the first Water pass than in the second or subsequent passes; however, because of the lower water temperature in the first pass, the latterhas the greater condensing capacity. Forexample, with a two-pass condenser having substantially equal numbers of tubes in-each pass, the first pass may have a capacity'for condensation of the order, of 60 to 65 percent of the total capacity of the condenser. In order that the passes may be arranged to accommodate steam inproportion to the capacities thereof, the tubes of the first pass should have greater spacing or pitch than the second and so on. Therefore, in accordance with our invention, we provide a condenser wherein the tubes of the first pass are spaced further apart or are more widely pitched than those of the subsequent pass, to provide greater flow area for the increased quantity of steam entering the first pass.

A further object of our invention is to. provide a condenser of the multiple-pass type with the tubes of each pass directly'exposed to entering steam and with the spacing or pitch of the tubes of the passes a'maximum in the initial pass and a minimum in the final pass.

A further object of our invention is to provide a radial flow condenser having the tubes arranged in horizontallyjuxtaposed first and second passes of substantially equal arcuate extent and wherein the tubes of the first pass occupy a relatively larger cross-sectional area of the nest than those of the second pass so that the tubes of the first pass may be more widely spaced.

A further object of our invention is to provide a radial flow condenser having the tubes arranged in horizontally juxtaposed first and second passes of substantially equal arcuate extent and the group of tubes of the first pass being so arranged that a central portion protrudes reentrantly within the group of tubes of the second pass, thereby providing greater area for the first pass so that the tubes of the latter may be more widely spaced.

A further object of our invention is to provide a radial flow condenser with the tubes arranged in horizontally juxtaposed first and second passes wherein the tubes of the first pass include a central group protruding within the group of tubes of the second pass so that the tubes of the first pass may be more widely spaced and so that a laterally symmetrical air ofitake may be arranged within the confines of the tubes of the first and colder pass.

These and other objects are effected by our invention as will be apparent from the following description and claims taken in connection with the accompanying drawing, forming apart of this application, in which:

Fig. l is a transverse sectional viewof a coninto inlet'and outlet chambers l1 and I8, respectively. The chamber Ii, is provided with an inlet connection i9 while the chamber i8 is provided'with a corresponding outlet connection 2|. A plurality of tubes 22 extend longitudinally of the shell from the waterbox !3 to the waterbox,

l4 whereby water entering ,the inlet chamber of the box [3 may. flow through certain of. the tubes 22xto the waterbox it where the flow is reversed. and the water conveyed through the remaining tubes to the outlet chamber I8 of the Water box l3.

The tubes 22 form a radial-flow tube nest 23 of substantially circular cross-section and are so disposed as to define, with respect to the shell, a steam space diminishing in cross sectional area from the steam inlet opening l2 at the top of the condenser to the bottom of the shell. By this arrangement, steam may freely enter the tube nest at all points around its periphery.

At the center of the tube nest 23, is an air oiftake core 25, extending the entire length thereof. Exhaust pipes 28 and 29 conduct the air and non-condensable gases from the oiftake to the exterior of the condenser, in a well known manner.

Steam, entering the condenser through the inlet opening I2 at the top thereof, passes radially among the tubes of the nest 23, and is condensed, air and non-condensable vapors passing into the offtake 2%, the bailies 3| and 32 providing for distribution of steam in the nest. The lowermost portion of the shell has one or more openings 36 for conducting condensate to a suitable hotwell (not shown).

The tube nest 23, as herein illustrated, consists of a first pass 31 and a second pass 38. The first pass has a greater cross-sectional area than the second pass, as indicated by the dotted line showing of the partition I6 which divides the waterbox l3 into inlet and outlet chambers.

Both passes are provided with approximately the same number of tubes of the same size; and, since the first pass has a greater cross-sectional area than the second pass, the tubes of the first pass are spaced farther apart than those of the second pass, as may be seen from Fig. 2. This construction provides more space for flow of steam between the tubes of the first pass than between those of the second pass.

While the passes are of equal peripheral extent, the wider spacing of the tubes of the first pass provides greater entrance area to accommodate the relatively greater quantity of steam which may be condensed by the first pass. thermore, if the greater cross-sectional area of the first pass to obtain the wider tube spacing is secured by having a portion of the tubes of the first pass protrude reentrantly into the tubes of the second pass, such protruding portion of tubes is used to enclose the air offtake to advantage, not only for the reason that a symmetrical location of the air offtake is preserved, but for the further reason that such offtake is entirely surrounded by the relatively cooler tubes of the first pass.

While we have shown herein a condenser having only two passes, it will be clear to those skilled in the art that the same principles of contruction can be applied to condensers having a greater number of passes with equally advantageous results.

While we have shown our invention in but one form, it will'be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and we desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What we claim is:

1. In a condenser, a shell, a nest of tubes within the shell and defining a steam space with respect to the latter and the shell having an exhaust steam admission opening communicating with the space, means providing an air offtake, and means cooperating with the tubes to provide for flow of water therethrough in a plurality of passes in succession, each pass having tubes directly exposed to said steam space so that steam fiows from the latter in parallel through the passes toward the ofitake and the tubes of the first pass being more widely spaced than those of the final pass.

2. In a condenser, a shell, a nest of tubes within the shell and defining a steam space with respect to the latter and the shell having an exhaust steam admission opening at the top thereof communicating with the space, means cooperating with the tubes to provide for fiow of water therethrough in a plurality of passes in succession, and an air ofitake, said passes being comprised by horizontally juxtaposed groups of tubes and the outermost tubes of each group being directly exposed to said steam space so that steam flows from the latter in parallel among the tubes of the passes toward the air ofitake and said groups being of substantially equal arcuate extent with the tubes of the initial pass occupying a larger cross-sectional area than the tubes of the final pass and with the spacing of the tubes of the first pass greater than that of the final pass.

3. In a condensena shell, a nest of tubes within the shell and defining, with respect to the latter, a steam space which substantially encompasses the nest and the shell having an exhaust steam admission opening communicating with the space, means cooperating with the tubes to provide for flow of water therethrough in first and second passes, the tubes of the passes being arranged in horizontally juxtaposed groups of substantially equal numbers of tubes and of substantially equal peripheral extents, the tube group of the first pass protruding reentrantly into the tube group of the second pass, with the cross-sectional area occupied by the first pass larger than that of the second pass and with the tubes of the first pass more widely spaced than those of the second pass, and an air offtake encompassed by tubes of the first pass and arranged at the region of the protruding tubes thereof, the outermost tubes of each pass being directly exposed to said steam space so that 50 steam fiows from the latter in parallel through the passes toward the ofitake.

CHARLES B. TULEY. JOHN W. MCNUL'I'Y.

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