US2140739A - Tubular unit for water walls or the like - Google Patents

Description

Patented Dec. 20, 1938 UNITED STATES 2,140,739 H TUBULAR UNIT FOR. WATER WALLS OR THE LIKE Herbert Frank, Kassel-Wilhelmshohe. Germany, assignor to The Superheater Company, New

York, N. Y.

Application January 30, 1937; Serial No. 123,189 In Germany February 5, 1936 4 Claims. (01. 122 -235) The present invention relates to improvements in water walls for the combustion chambers of boilers or the like.

It has been the practice heretofore to cool a furnace wall in a boiler by circulating boiler water through tubes arranged in a row on the inner surface of the wall. In some cases bifurcated tube units have been employed and the constituent tubes have been curved near their ends to extend through the wall, both the curved tube portions and the bifurcations which join them to single tube lengths that connect into the boiler circulation system being located within or outside the wall. Where the bifurcations of the units are disposed so that the tube portions passing through the wall lie parallel to each other in a horizontal plane, the openings made through the wall are relatively broad and consequently impair the strength of the wall.

In accordance with the present invention the bifurcation or breeches piece of a unit which joins the two tubes thereof that lie on the inner surface of the wall is turned into a plane which is substantially at right angles to the tube portions on the wall so that in each unit the portions of the two tubes which extend through the Wall are disposed above each other in a vertical plane at right angles to the wall surface. As a result, the openings formed in the wall for extending the units therethrough are about as narrow as would be required for a single tube.

In the drawing Fig. l is an elevational view, partly broken away, of a portion of a furnace wall having cooling tubes arranged thereon in accordance with the invention.

Fig. 2 is a sectional view on the line 2-2 in Fig. 1 and shows the manner in which the end portions of the tubes and the bifurcations joining the latter are arranged so that the portions of the tubes projecting through the wall are disposed in a single vertical plane, and

Figs. 3 and 4 are views similar to Figs. 1 and 2, respectively, but showing an arrangement in which only one end of a unit has been bent in accordance with the invention.

Referring to the drawing, the numeral I ll designates a furnace wall on the inner surface of which is arranged a plurality of bifurcated cooling units II having portions near their ends projecting through the wall and communicating with inlet and outlet headers I'l, I8 connected into the circulation system of the boiler. Each unit I I comprises a pair of tubes I 2, I3 extending vertically of the wall and joined at each end by a bifurcation or breeches piece I4 to each other and to single tube lengths I6 connected with the headers I1 and I8. The tubes I2 and I3 of all the units are arranged'parallel to the wall surface and as shown are disposed close togetherin a single row in a vertical plane parallel to the wall surface. If desired, the units might be connected to'function as a superheater.

In accordance with the invention the bifurcation. l4 at each end of a unit I I isbent at substantially a ri ht angleto the tubes I2 and I3 thereof so that the curved tube portions l'iwhich extend through the wall are located one above the other in a vertical plane perpendicular to that of the inner surface of the wall. As a result of this arrangement the apertures made in the wall to permit the units II to be connected with the headers I'I, I8 are narrower than would be the case if the tube portions projecting through the wall laid alongside of each other instead of being in a vertical plane. Consequently the wall is not weakened to the extent that it would be if the two tubes laid alongside each other where they passed through the wall because, in accordance with the invention, the openings in the wall are about as wide as a single tube and are spaced transversely of the wall. This feature is of particular advantage in situations where, as shown in Fig. 2, the upper portion ofa boiler wall is supported on a beam 20 or the like extending transversely of the wall at a point near the upper end of the cooling units I I inasmuch as the wall ligaments 2| between the apertures for superposed tube portions I5 of adjacent units II provide a means for supporting the upper portion of the wall on the beam 20.

A further advantage is that a water wall consisting of bifurcated units may be readily installed in existing boilers. Only narrow apertures need be cut in the Wall to receive the superposed end portions of the tubes and the ligaments left between the apertures support the upper part of the wall while installing the bifurcated units.

Another advantage is that even in cases where the bifurcations or breeches pieces I4 are not located within or outside the wall they are protected against heating by radiation from the fire inasmuch as they are located behind the tube lengths I2, I3 which they join to form a unit.

In the arrangement illustrated in Fig. 3 the upper ends of the units I I project through the wall Ill near the top thereof and accordingly only the bifurcation at the lower end of each unit is bent to dispose the tube portions I5 in a vertical plane.

What I claim is:

1. In combination with a wall of a furnace or the like; a cooling screen therefor comprising a plurality of fluid circulating tubes disposed alongside each other in a row parallel to the inner surface of the wall and having portions near their ends projecting through said wall, said tube portions at at least one end of the tubes of each pair of adjacent tubes being bent at an angle to the portions thereof which line said wall and disposed in superposed relation in a vertical plane perpendicular to that of said wall surface so that the aperture formed in said wall for projecting said tube portions therethrough is of a width corresponding approximately to the diameter of a tube.

2. In combination with a wall of a furnace or the like; a cooling screen comprising a plurality of bifurcated, tubular, fluid circulating units arranged in a row on the inner surface of said wall, each unit consisting of a pair of tube lengths lying alongside each other in a plane parallel to said wall surface and having end portions extending through said wall and joined by a breechespiece disposed in a vertical plane perpendicular to the surface plane of said wall for disposing said end portions in superposed relation in said vertical plane, whereby the aperture formed in said wall for extending the tube portions of each unit therethrough is of a width substantially corresponding to the diameter of a tube of the unit.

3. In combination with a wall of a furnace or the like; a cooling screen comprising a plurality of bifurcated, tubular fluid circulating units each comprising a pair of parallelly extending tubes disposed alongside each other in a plane parallel to the surface of said wall and joined together at each end by breeches pieces and having the end portions of each tube adjacent said breeches pieces bent at an angle to the major portion of said tube to extend through said wall and disposed in superposed relation in a plane at right angles to a plane passing through the axes of said major portions of said tubes.

4. In combination with a substantially vertical wall of a furnace or the like; a cooling screen therefor comprising a plurality of fluid circulating tubes spaced at distances less than a tube diameter and arranged in a single row disposed in a plane parallel to the inner surface of said wall and having portions near their ends projecting through said Wall and connected to a header located exteriorly of said furnace, said tube portions at at least one end of the tubes of each pair of adjacent tubes being bent at an angle to the portions thereof which line said wall and disposed in superposed relation in a vertical plane perpendicular to that of said wall surface so that the aperture formed in said wall for projecting said tube portions therethrough for connection to said headers is of a width corresponding approximately to the diameter of a tube.

HERBERT FRANK.

Images