DE1679396B2 - HEATING BOILERS FOR LIQUID OR GAS FUELS - Google Patents

Description

The invention relates to a heating boiler for liquid or gaseous fuels, with a horizontal cylindrical water jacket and an off-center offset downwards, ar one end closed combustion chamber and above the combustion chamber arranged flue gas ducts, the are connected by an overflow chamber to the open end of the combustion chamber.

In the case of heating boilers of the type mentioned above, it is usually customary to place the boiler horizontally or to be set up horizontally and the combustion chamber offset eccentrically downwards in the water jacket to arrange. Other spatial arrangements with basically the same construction are not excluded. The z. B. from the DT-AS 10 49 038 known heating boiler the aforementioned construction have a combustion chamber, which is the usual, known shape of a Circular cylinder has. so that the at the closed end of the combustion chamber deflected by 180 ° and to Combustion gases flowing back through the open end of the combustion chamber through a round, open end of the combustion chamber exit from the combustion chamber and then around the flue gas ducts above the combustion chamber to flow through, the side by side and one above the other arranged pipes with round or square Cross-section exist.

From DT-GM 19 37 831 it is known to use hollow profiles for the flue gas ducts of a heating boiler an elongated, flat cross-section deviating from the round or square cross-sectional shape apply.

The invention has the task of providing a heating boiler of the type mentioned at the beginning create, with the compact, simple boiler construction an improvement and equalization the admission of the flue gas ducts is achieved and with which an increase in the heat transfer to the boiler water and thus an increase in boiler output can be achieved.

This object is achieved according to the invention in that the combustion chamber has a at its open end has an oval cross-section, whose small diameter through the center and whose large diameter runs at a distance below the center of the water jacket.

Advantageously exist with this boiler the flue gas ducts made of known hollow profiles with a flat, approximately oval cross-section, its large clear width essentially perpendicular to the large diameter of the oval combustion chamber end is arranged and designed to decrease continuously in the flow direction of the combustion gases.

While with a circular open combustion chamber

the exiting gas flow ends at its side areas, i.e. in the outer flue gas ducts acting on the edge zones, compared to its central area is weak, so that the outer Flue gas channels are less strongly flowed through than the middle smoke gas channels, as through the oval Shape of the open end of the combustion chamber, the gas flow returning in the combustion chamber is shaped in such a way that that it has a significantly increased volume at the more pointed parts of the oval, d. H. in the area of the outer Flue gas ducts, exit. Also the outer smoke ducts are therefore intensively acted upon and flowed through by combustion gases, so that an improved Utilization of the heat exchange surface of these flue gas ducts occurs and especially in these flue gas> 5 channels the risk of hypothermia and corrosion is avoided. Practical tests have shown that the difference in temperatures with which the combustion gases in the middle respectively enter the outer smoke ducts, at oval * ° formed open combustion chamber end is significantly lower than with conventional circular open Combustion chamber end.

Furthermore, due to the oval shape of the open end of the combustion chamber, it is precisely at this end of the combustion chamber a widening of the water space required for the arrangement of the flue gas ducts between Combustion chamber wall and outer wall of the water jacket achieved, so that when using an ordinary and easy to manufacture cylindrical sheet metal jacket as the outer wall of the water jacket enough space in the water space for the pocket-shaped hollow profiles with flat, roughly oval ones Cross-section is available, the large clear width is greatest at the open end of the combustion chamber. Have along at the open end of the combustion chamber the combustion chamber wall and the outer wall of the water jacket due to the oval Formation of the open end of the combustion chamber in a substantial width extension is essentially one equally high spacing, so that pocket-shaped hollow profiles with practically the same large clear width can be arranged side by side in the water room.

Since the large inside width of the pocket-shaped hollow profiles arranged next to one another in the direction of becomes smaller towards the closed end of the combustion chamber, which is easy to manufacture, on the one hand, becomes a steady one Reduction of the clear cross section of the hollow profiles in the direction of flow of the gases and thus an im substantially constant high speed of the cooling combustion gases achieved what has a beneficial effect on the heat transfer, and on the other hand, makes it possible to use the closed end of the combustion chamber can train with enlarged Lichiem cross-section. The flat in cross-section and approximately oval hollow profiles have a very large surface and therefore the advantage that with few hollow profiles a sufficiently large, required heat exchange surface of the flue gas ducts can be achieved and hence the manufacturing costs caused by welding the flue gas ducts into the boiler can be reduced. Furthermore, the flat hollow profiles have the significant advantage that sieve not in such a hollow profile as in a pipe with a circular or square cross-section hot, not or only imperfectly used gas core forms in the flow, so that on Turbulators. such as B. insert spirals or the like ..

can be dispensed with.

Despite the large bowl heating surface. which enables a high boiler output, the heating boiler has a compact, pressure-resistant construction, so that for the boiler walls acted upon by the pressure of the boiler water no disproportionately high wall thicknesses are required. The vertical side faces of the flat Hollow profiles can be stiffened by transverse inwardly protruding beads so that they are also have a positive effect on the turbulent flow of the combustion gases in the hollow profiles.

The combustion chamber can advantageously be designed in such a way that its cross-section differs from the oval Shape at the open end of the combustion chamber merges evenly into the circular shape at the closed end of the combustion chamber and both combustion chamber ends have an equal or substantially equal circumference. on This can be done cheaply at first from an ordinary square sheet metal sheet and a round base a cylinder is welded together, which then simply becomes the desired oval at the open end Shape is compressed.

An advantageous embodiment of the heating boiler consists in that a shut-off wall is arranged at the open end of the combustion chamber, which is on the Flue gas channels facing away from the side has an outlet opening that water-bearing in the overflow chamber Finned tubes are arranged, the ribs of which run parallel to the gas flow, and that between the shut-off wall and a cover closing the overflow chamber into the combustion chamber opening burner tube is arranged. This makes the space of the overflow chamber valuable exploited and the boiler heating surface and the boiler efficiency increased to a significant extent. the Combustion gases, which also form the combustion chamber in a wide gas flow that is strong at the edge zones leave, are forced to flow through the overflow chamber on the longest possible path, whereby they intensely the finned tubes or their substantially parallel to the gas flow Smear the ribs and, before they enter the smoke duct, transfer their warmth to a large extent Dispense boiler water. The finned tubes are preferably vertical, so that the boiler water in them can easily circulate. Here, corrugated ribbon finned tubes, which will be explained in more detail, prove to be due to their very large and effective heat exchange surface as particularly favorable.

Further features within the scope of the invention are characterized in the subclaims.

Various exemplary embodiments of the invention are shown in the drawings. It shows

Fig. 1 a vertical center section through the boiler,

Fig. 2 shows a cross section along the line 11-11 in Fig.l,

F i g. 3 another embodiment of the heating boiler in a vertical central section,

4 shows a cross section along the line IV-IV in Fig. 3,

F i g. 5 a further embodiment of the heating boiler in a vertical center section,

6 shows a cross section along the line VI-VI in FIG.

7 shows an embodiment of a finned tube in a view,

8 shows a cross section along the line VIH-VIIl in

ίο

9 to 11 another embodiment of the flue gas ducts of the heating boiler.

The heating boiler in FIG. 1 and 2 has one by a cylindrical outer wall 1 bounded water jacket 2, offset in the eccentric downwards a combustion chamber 3 is arranged. The combustion chamber 3 has a circular closed combustion chamber end 4 and an oval open combustion chamber end 5. The large diameter of the oval open combustion chamber end 5 is at a distance next to, i.e. H. below the center of the outer wall 1 of the water jacket 2, while the small diameter of this oval combustion chamber end 5 runs through this center point. The circumferential half of the water jacket 2 having the greater radial width, d. H. the one above The part of the water jacket 2 located in the combustion chamber 3 is penetrated by flue gas ducts 6.

These flue gas ducts are formed by pocket-shaped hollow profiles with a flat, approximately oval clear cross-section. The hollow profiles stand with their large clear width perpendicular to the large diameter of the oval combustion chamber end 5 and are arranged next to one another with a distance between their wide side surfaces. While the clear distance between the closely spaced wide side surfaces of a hollow profile remains unchanged, the large clear width of each hollow profile decreases continuously in the flow direction of the combustion gases. At the open end of the combustion chamber 5, the combustion chamber 3 and the flue gas inside 6 are connected by an overflow chamber 7 which is closed by a cover 8 which carries the burner 9 protruding into the open end of the combustion chamber 5. The combustion gas flow flowing back in the combustion chamber 3 to the open combustion chamber end 5 is deformed by the oval shape of the open combustion chamber end 5 into a broad and intense gas flow at the lateral edge zones so that the outermost left and right flue gas ducts 6 are also intensely exposed to combustion gases. Due to the continuously decreasing height of the hollow profiles, the speed of the cooling combustion gases remains essentially constant, so that consistently good heat transfer values are achieved over the entire length of the flue gas ducts 6. The hollow profiles can be easily produced from a simple sheet metal strip, which by wedge-shaped cutting and bending around its longitudinal direction and welding together at the abutting longitudinal edges results in a hollow profile with a continuously decreasing large clear width. The wide side surfaces of the hollow profiles are stiffened with inwardly projecting beads 10 running transversely to the longitudinal direction. Since the front oval shape gradually merges into the rear circular shape and both combustion chamber ends have essentially the same circumference, the combustion chamber 3 can be produced as a simple round base on a fourth jacket plate, the cylinder formed by these two parts being inserted into the open follicle The desired oval shape is compressed. With a large heating surface and high output, the boiler has a squat, compact shape that is stable against the effects of the boiler water pressure. .

In the heating boiler of FIGS. 3 and 4, the open merende 5 eaie shut-off wall 20 is arranged which only leaves an outlet opening 21 from the combustion chamber 3 to the overflow chamber 7 on the side of the large diameter of this oval combustion chamber end 5 facing away from the flue gas ducts 6. The combustion gases are forced to exit the combustion chamber 3 at about the lowest point of the overflow chamber 7 and to flow through the overflow chamber 7 as long as possible to the flue gas ducts 6. The shut-off wall 20 is provided with a burner tube 22 which opens into the combustion chamber 3 and extends through the overflow chamber 7 to the cover 8. The shut-off wall 20 and the burner tube 22 are designed as walls carrying boiler water. In the

'5 overflow chamber 7 are transverse to the large diameter of the oval end of the combustion chamber, that is, finned tubes 23 carrying vertically standing boiler water arranged. These finned tubes are coated by the combustion gases flowing up, so that

an intensive heat transfer to the boiler water takes place in the overflow chamber 7 before the combustion gases enter the flue gas channels 7. In this way the overflow chamber is in exploited extremely economically. the

Finned tubes 23 are arranged so that the openings of the flue gas channels opening into the overflow chamber 7 6 are uncovered. In this way, after the cover 8 has been pivoted away, the smoke gas ducts 6 cleaned between the finned tubes 23 through

will. The combustion chamber 3 is readily accessible below the burner tube 22 for cleaning, since no finned tubes are required on the underside of the burner tube 22.
The heating boiler in FIG. 5 and 6 corresponds to im

Principle of the heating boiler in fig. 3 and 4. Here, however, the overflow chamber is not part of the Heating boiler, but part of an approximately bell-shaped formed cover 30, the recess on the inside of the cover an overflow chamber 31 forms. The cover 30 is designed as a boiler water-conducting part and there are also here in the Übersirömkammer 31 vertically standing finned pipes 32 carrying boiler water are arranged on its inside the cover 30 is provided with a burner pipe 33 which carries boiler water and extends through the overflow chamber 31 extends through into the open combustion chamber end 5, this open combustion chamber end 5 is provided with a shut-off wall 34 leading to the boiler water, which for the most part only on the of the

Flue gas channels 6 facing away from the large diameter of this oval combustion chamber end 5 leaves an outlet opening 35 from the combustion chamber 3 to the overflow chamber 31. The combustion gases are also forced here, as deep as possible and with

wide gas flow strong at the edge zones in the overflow chamber 31 to enter and this up to the flue gas ducts 6 on the longest possible way zn flowa Since the finned tubes 32 are arranged on the inside of the cover 30 and with the cover 30,

which is connected to the boiler by a hinge 36 can be washed away from the boiler, the flue gas ducts 6 and the open combustion chamber end 5 are completely free from the front for cleaning and inspection purposes.

° 5 As a result, on the inside of the lid 30 a large number of closely spaced beaded Tilt pipes are arranged, which in GescMesseBef position of the ceiling 30. as Fig. «shows, also before 46»

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Openings in the flue gas ducts 6 can be located and also on the underside of the burner tube 33 can be provided. In addition, this boiler construction offers the further great advantage that the recess forming the overflow chamber 31 on the inside of the cover 30 is dimensioned as deep as desired can be to selectively only one row of finned tubes or according to FIG. 5 two rows of finned tubes or more than two rows of finned tubes to be welded into the cover 30, so that without any welding ar- io work on the boiler by simply replacing the cover 30, the boiler output varies, for example can be increased considerably by using a cover with three or more rows of finned tubes. With this boiler construction, the finned tubes are also more accessible for cleaning purposes make, since the water-cooled lid easily has additional cleaning openings on its outside can be provided so that the finned tubes are accessible from two sides. At their lowest and 20th The highest points are the water jacket 2 and the cover 30 through pipes 37 water-bearing tied together. These pipes 37 have flexible metal hoses in the area of the pivot axis of the hinge 36, so that the cover 30 can be pivoted 25 without emptying the boiler and the To have to dismantle pipes 37.

So that the ribs of the finned tubes 23 {F i g. 3) and 32 (Fig. 5) on their entire The rib surface can be swept intensively by the combustion gases 30, the ribs are like this arranged so that they are substantially parallel to the gas flow. As finned tubes that are in Extending gas flow direction, which is therefore according to FIGS. 3 to 6 across the large diameter of the oval 35 At the end of the combustion chamber and arranged vertically, so-called corrugated ribbed tubes are used, which is characterized by an extraordinarily large heat exchange surface of the ribs with relatively characterized by a low overall diameter and an extraordinarily high heat transfer capability, in fig. 7 and 8 is an exemplary embodiment of such a corrugated ribbed tube. Two elongated corrugated strips 40 and 41 are formed from two metal strips and are positioned next to one another 45 lying with a correspondingly adapted slope on the outer surface of a cylindrical tube 42 in a helical shape are wound up. At their points of contact with the outer surface of the tube 42 are the Corrugated strips 40 and 41 are connected to the tube 42 in a metallic and thermally conductive manner. As Fig. 8 shows, can easily be achieved by using two corrugated tapes that that of the corrugated tapes formed ribs from turn to turn are offset from one another, so that the corrugated ribbon ribs each Winding inside and outside can be acted upon intensively by the combustion gases.

Instead of the pocket-shaped hollow profiles described, cylindrical tubes can also be used as flue gas ducts 6 can be used, if necessary, to take advantage of the continuous tapering of the flue gas ducts should be omitted in the gas flow direction. However, the cylindrical tubes then become like this formed that in its wall extending in the circumferential direction, cross-sectional constrictions forming indentations are arranged. For this purpose, FIG. 9 to 11 show an exemplary embodiment. Fig.9 shows a view of a cylindrical tube 50, in the wall of which bead-shaped at intervals or groove-shaped indentations 51 are impressed. F i g. 10 shows a cross section through the pipe 50 according to FIG the line X-X in FIG. 9 and FIG. 11 a longitudinal section through the pipe 50 according to the line XI-XI in FIG. 9. The indentations 51 result in a smooth cylindrical tube a kind of grooved tube. The indentations, which can be made easily and with uncomplicated tools Ordinary cylindrical tubes can be pressed in, have the advantage that the combustion gases are swirled vigorously and thereby give off their heat intensively and that therefore special built-in components such as B. twisted sheet metal strips that have been conventional smooth cylindrical tubes for the purpose of achieving a gas turbulence had to be provided in addition to be superfluous. One can at each cross-section Ie of the tube 50 arrange two indentations 51, dk, as Fig. 10 illustrates, diametrically opposite overlay, but you can also, for example, three groove-shaped indentations distributed over the circumference of the pipe or provide a single, annular circumferential indentation.

4 sheets of drawings «9523 /;

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Claims (10)

Claims 1. Heating boiler for liquid or gaseous fuels, with a horizontal cylindrical water jacket and an eccentrically offset downward, closed combustion chamber at one end and flue gas ducts arranged above the combustion chamber, which are connected to the open end of the combustion chamber by an overflow chamber, thereby ¹⁰ indicates that the combustion chamber (3) at its open end (5) has an oval cross-section, the small diameter of which runs through the center and the large diameter at a distance below the center of the water jacket (2) 2. Heating boiler according Ansoruch 1, characterized in that the flue-gas ducts (6) consist of per se known hollow profiles with a flat, approximately oval cross-section, arranged whose large clearance ^m width substantially perpendicular to the major diameter of the oval combustion chamber end (5) and in Strömmungsrichtung the combustion gases is designed to decrease continuously. * 5 3. Heating boiler according to claim 2, characterized in that on the vertical side surfaces of the flue gas ducts (6) transversely to the longitudinal direction, inwardly protruding beads (JO) are arranged. 4. Heating boiler according to claim I, characterized in that the flue gas ducts (6) from cylindrical tubes (50) are gebi.Het, in the wall extending in the circumferential direction. Cross-sectional constrictions forming indentations (51) are arranged. 5. Heating boiler according to claim 1, characterized in that the cross section of the combustion chamber (3) from the oval shape at the open end (5) evenly to the circular shape at the closed end End (4) passes over and both combustion chamber ends have the same circumference. 6. Heating boiler according to claim 1, characterized in that at the open end of the combustion chamber (5) a shut-off wall (20) is arranged, which on the side facing away from the flue gas ducts (6) a Has outlet opening (21) that in the Übersirömkammer (7) water-bearing finned tubes (23) are arranged, the fins of which are parallel to the gas flow run, and that between the shut-off wall (20) and one of the overflow chamber (7) closing Cover (8) a burner tube (22) opening into the combustion chamber (3) is arranged. 7. Heating boiler according to claim 6, characterized in that in the overflow chamber (7) vertically standing corrugated ribbon finned tubes (40, 41, 42) are arranged. 8. Heating boiler according to claim 6 or 7, characterized in that the shut-off wall (20) and the burner tube (22) are designed as water-bearing parts of the water jacket (2). 9. Heater body according to claim 7, characterized in that the corrugated ribbon finned tubes (40, 41, 42) leaving open the openings of the flue gas ducts (6) opening into the overflow chamber [7) & 5 are arranged. 10. Heating boiler according to claim 6 or 7, characterized in that the overflow chamber (31) is arranged in a designed water-bearing deck (30) which is on its inner rope has water-bearing finned tubes (32) that dj burner tube (33) as the water-bearing part de Lid (30) is formed and below de shut-off wall (34) in the open combustion chamber end (5) protrudes, and that the cover (30) can be pivoted by means of a hinge (36) and through in the area the pivot axis of the hinge (36) flexible pipelines (37) carrying water mi connected to the water jacket (2).