EP1600708A1 - Method of producing a gas boiler, and gas boiler so produced - Google Patents

Method of producing a gas boiler, and gas boiler so produced Download PDF

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Publication number
EP1600708A1
EP1600708A1 EP05104398A EP05104398A EP1600708A1 EP 1600708 A1 EP1600708 A1 EP 1600708A1 EP 05104398 A EP05104398 A EP 05104398A EP 05104398 A EP05104398 A EP 05104398A EP 1600708 A1 EP1600708 A1 EP 1600708A1
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EP
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Prior art keywords
pipe
length
axis
fins
boiler
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EP05104398A
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German (de)
French (fr)
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EP1600708B1 (en
EP1600708B8 (en
Inventor
Marco Tagliaferri
Christian Cannas
Noè Ciofolo
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Elbi International SpA
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Riello SpA
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/22Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating
    • F24H1/40Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating with water tube or tubes
    • F24H1/43Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating with water tube or tubes helically or spirally coiled

Definitions

  • the present invention relates to a method of producing a gas boiler.
  • a gas boiler is normally designed to produce hot water for domestic use or for space heating, and comprises a gas burner, and at least one heat exchanger through which the combustion fumes and water flow.
  • Some types of gas boilers known as condensation boilers, condense the steam of the combustion fumes by transferring the latent heat of the fumes to the water.
  • Condensation boilers are further divided into a first and second type. Gas boilers of the first type are normally equipped with a first exchanger close to the burner; and a second exchanger downstream from the first exchanger along the fume path and designed solely for fume condensation.
  • Gas boilers of the second type are equipped with a single heat exchanger which, along a first portion, provides solely for heat exchange, and, along a second portion, in addition to heat exchange, also provides for fume condensation.
  • Both exchangers for fume condensation only (first type) and dual-function exchangers (second type) comprise a casing extending along a first axis and through which the fumes are conducted; and a pipe along which water flows, and which is coiled into a succession of turns. The fumes flow over and between the turns to transfer heat to the water flowing along the pipe.
  • the coiled pipe has fins extending perpendicularly to the pipe axis.
  • exchanger pipes are normally of complex shapes to enhance heat exchange between the water and fumes, and, at the same time, are made of materials of high thermal conductivity.
  • the complex shape of the pipes makes it difficult to connect the pipes to the water circuit; so much so that, very often, they are welded directly to the water circuit. Welding, in turn, poses practical problems, such as welding cost, and the fact that the weld region in contact with the fumes and possibly also with fume condensate is highly susceptible to corrosive chemical reactions.
  • the present invention also relates to a gas boiler.
  • Boiler 1 is a wall-mounted condensation boiler, i.e. of the type in which the steam in the fumes is condensed, and comprises a heat generating and exchange unit 2, in which are fitted a burner 3 and an exchanger 4; an air/gas mixture feed pipe 5; a fume exhaust pipe 6; and a water circulating circuit 7 defined by substantially circular-section pipes.
  • Unit 2 is substantially cylindrical, extends along a substantially horizontal axis A1, and comprises a casing 8 through which the fumes flow; a finned pipe 9 along which water flows; and a disk 10 for imposing a given fume flow path inside casing 8.
  • Exchanger 4 substantially comprises pipe 9 and casing 8, which also acts as a combustion chamber for burner 3 housed inside casing 8.
  • Casing 8 comprises a cylindrical lateral wall 11 of axis A1; a cover 12 connected to lateral wall 11, to pipe 5, and to burner 3; and a cover 13 connected to lateral wall 11 and to exhaust pipe 6. Covers 12 and 13 have respective openings 14 and 15, through which the ends of pipe 9 are inserted for connection to circuit 7.
  • Burner 3 extends coaxially with casing 8 and for a given length inside cylindrical lateral wall 11, while pipe 9 forms a coil about an axis A2 substantially coincident with axis A1, and comprises a succession of adjacent turns 16, each located close to lateral wall 11.
  • Exchanger 4 also comprises three comb-like spacers 17 (only one shown in Figure 1) for keeping turns 16 a given distance apart and for keeping the whole of coiled pipe 9 at a given distance from lateral wall 11.
  • Pipe 9, disk 10, and spacers 17 define inside casing 8 a first central region housing burner 3; a second central region communicating directly with the exhaust pipe; and three lateral regions, each extending between two adjacent spacers 17, turns 16, and lateral wall 11. Combustion of the air-gas mixture takes place in the first central region.
  • the combustion fumes are prevented by disk 10 from flowing directly into the second central region, and flow between turns 16, in a direction D1 substantially perpendicular to axis A1, into the three lateral regions, along which they flow in a direction D2 substantially parallel to axis A1. Once inside the lateral regions, the fumes flow between turns 16 in direction D1 into the second central region and then along exhaust pipe 6.
  • Pipe 9 which is preferably made of aluminium or aluminium alloy, is formed from an extruded pipe length 18 extending along a straight axis A3, as shown in Figure 2.
  • Pipe length 18 is cut to a length L1 from which to form pipe 9, and comprises a wall 19; two fins 20 on one side of pipe length 18; two fins 21 on the opposite side to fins 20; a fin 22 between fins 20; and a fin 23 between fins 21.
  • the cross section of pipe length 18 is substantially oval, and has a major axis X and a minor axis Y. Fins 20, 21, 22, 23 are all co-extruded with wall 19, are parallel to axis A3 and major axis X, and are therefore parallel to one another.
  • Fins 22 and 23 are coplanar, and lie substantially in the same plane as axis A2 and major axis X. Fins 20 and 21, on the other hand, are located so that each fin 20 is coplanar with an opposite fin 21, and wall 19 of pipe length 18 forms a slight bulge between the coplanar fins 20 and 21.
  • the maximum extension of fins 20 and 21, in a direction parallel to major axis X, is roughly equal to a quarter of the length of major axis X.
  • pipe length 18 is machined to remove fins 20, 21, 22, 23 from two opposite end portions 18a of pipe length 18, to a given length L2 (only one end portion 18a of pipe length 18 is shown in Figures 2 to 10).
  • pipe length 18 is then coiled about an axis A2, so that axis A3 of pipe length 18 is also coiled.
  • This operation comprises calendering pipe length 18, while maintaining minor axis Y of the cross section of pipe length 18 substantially parallel to axis A2.
  • the relatively small size of fins 20, 21, 22, 23 does not hinder the calendering operation, and is such that no cutting of fins 20, 21, 22, 23 is required.
  • end portions 18a are bent square so that two endpieces 18b of end portions 18a are parallel to axis A2.
  • each endpiece 18b is worked mechanically to deform it permanently and transform its cross section from substantially oval to circular up to a length L3 smaller than length L2. This is done by placing each endpiece 18b inside a known variable-section die (not shown), and forcing a punch 24 inside endpiece 18b.
  • a bevel 25 is worked mechanically on the outer portion of wall 19 and at the opposite ends of pipe length 18 to remove any flaws or surplus material, thus forming pipe 9 from pipe length 18.
  • the three spacers 17 are then fitted between fins 21 of adjacent turns 16 and spaced 120 degrees apart to form, with pipe 9, an assembly which is inserted inside cylindrical wall 11 of casing 8.
  • axis A2 substantially coincides with axis A1, and turns 16 are maintained a substantially constant distance from wall 11 ( Figure 1).
  • Covers 12 and 13 are then fitted onto the opposite ends of cylindrical wall 11, and endpieces 18b of pipe 9 are inserted inside openings 14 and 15.
  • the coil of pipe 9 is of constant pitch and radius, so that fins 20 and 21 of each turn 16 face and are parallel to fins 20 and 21 of the adjacent turns 16, as shown in Figure 1. Between adjacent turns 16, a gap is thus formed, which is of constant width at fins 20 and 21, and narrows at the bulge in wall 19.
  • the successive gaps form compulsory fume paths, and, because of their shape, produce a venturi effect, which brings about a sharp acceleration in fume flow and increases turbulence to improve heat exchange.
  • fins 20 and 21 provide for both increasing the exchange surface of pipe 9 and accelerating fume flow and turbulence.
  • number 26 indicates two clamps for securing covers 12 and 13 to cylindrical lateral wall 11.
  • Each clamp 26 comprises an automatic fastener 27 (shown open in Figure 12), and has a C-shaped cross section, as shown in Figure 11.
  • wall 11 comprises two annular ribs 28 at opposite ends.
  • Each cover 12, 13 comprises a portion 29 insertable inside cylindrical lateral wall 11; and an outer portion 30 comprising an annular rib 31, which rests against respective rib 28 to form a seat housing a seal.
  • Each two ribs 28 and 31 are held together by one of clamps 26.
  • opening 15 (and likewise opening 14) is defined by a sleeve 33, the outer end of which has an internal thread.
  • Circuit 7 is connected to unit 2 by means of ring nuts 34, each of which is axially integral with circuit 7, is threaded externally to screw onto sleeve 33, and has a seat 35 housing a seal 36.
  • casing 8 communicates externally to exhaust the fumes, to receive gas and air, and to transfer water solely through covers 12 and 13.
  • Exchanger 4 as described above may also be used in condensation boilers featuring a main exchanger, and wherein exchanger 4 provides solely for condensing the fumes, and does not act as a combustion chamber, as in the example described.
  • Fins 20, 21, 22, 23 provide for increasing both heat exchange and turbulence, and, being parallel to axis A3 of the pipe length, can be extruded easily and, at the same time, can be machined off easily to form fittings.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Fluidized-Bed Combustion And Resonant Combustion (AREA)

Abstract

A method of producing a gas boiler (1) having a water/fume heat exchanger (4), in turn having a casing (8) and a pipe (9) housed inside the casing (8), includes cutting a straight pipe length (18) having fins (20, 21, 22, 23) and of a given length (L1) to form the pipe (9); removing the fins (20, 21, 22, 23) from opposite end portions (18a) of the pipe length (18); coiling the pipe length (18) about an axis (A2); and forming fittings directly on the end portions (18a) of the pipe length (18) to facilitate connection of the pipe (9) to a water circuit (7) outside the heat exchanger (4).
Figure 00000001

Description

  • The present invention relates to a method of producing a gas boiler.
  • A gas boiler is normally designed to produce hot water for domestic use or for space heating, and comprises a gas burner, and at least one heat exchanger through which the combustion fumes and water flow. Some types of gas boilers, known as condensation boilers, condense the steam of the combustion fumes by transferring the latent heat of the fumes to the water. Condensation boilers are further divided into a first and second type. Gas boilers of the first type are normally equipped with a first exchanger close to the burner; and a second exchanger downstream from the first exchanger along the fume path and designed solely for fume condensation. Gas boilers of the second type are equipped with a single heat exchanger which, along a first portion, provides solely for heat exchange, and, along a second portion, in addition to heat exchange, also provides for fume condensation. Both exchangers for fume condensation only (first type) and dual-function exchangers (second type) comprise a casing extending along a first axis and through which the fumes are conducted; and a pipe along which water flows, and which is coiled into a succession of turns. The fumes flow over and between the turns to transfer heat to the water flowing along the pipe. In some exchangers, the coiled pipe has fins extending perpendicularly to the pipe axis. Though this provides for highly effective heat exchange, producing fins perpendicular to the pipe axis calls for a high-cost production process. In other types of exchangers, the coiled pipe has a depressed flow section, which, though cheaper as a solution, is much less efficient in terms of heat exchange than the finned pipe solution.
  • As a result, exchanger pipes are normally of complex shapes to enhance heat exchange between the water and fumes, and, at the same time, are made of materials of high thermal conductivity. The complex shape of the pipes makes it difficult to connect the pipes to the water circuit; so much so that, very often, they are welded directly to the water circuit. Welding, in turn, poses practical problems, such as welding cost, and the fact that the weld region in contact with the fumes and possibly also with fume condensate is highly susceptible to corrosive chemical reactions.
  • It is an object of the present invention to provide a method of producing a gas boiler which, on the one hand, is highly efficient in terms of heat exchange, and, on the other, is cheap to produce.
  • According to the present invention, there is provided a method of producing a gas boiler, as claimed in Claim 1.
  • The present invention also relates to a gas boiler.
  • According to the present invention, there is provided a gas boiler as claimed in Claim 14.
  • A number of non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:
  • Figure 1 shows a section, with parts removed for clarity, of a gas boiler produced using the method according to the present invention;
  • Figures 2 and 3 show views in perspective, with parts removed for clarity, of a length of pipe at two distinct production stages in accordance with the method of the present invention;
  • Figures 4, 6 and 8 show front views, with parts removed for clarity, of the length of pipe in Figures 2 and 3 at further production stage;
  • Figures 5, 7 and 9 show plan views, with parts removed for clarity, of the pipe length in Figures 4, 6 and 8;
  • Figure 10 shows a larger-scale plan view of a further production stage in the method of the present invention;
  • Figure 11 shows a smaller-scale, side view, with parts removed for clarity, of the Figure 1 gas boiler;
  • Figure 12 shows a larger-scale front view, with parts removed for clarity, of a detail of the Figure 11 boiler;
  • Figure 13 shows a larger-scale section of a detail of the Figure 1 gas boiler.
  • Number 1 in Figure 1 indicates as a whole a gas boiler. Boiler 1 is a wall-mounted condensation boiler, i.e. of the type in which the steam in the fumes is condensed, and comprises a heat generating and exchange unit 2, in which are fitted a burner 3 and an exchanger 4; an air/gas mixture feed pipe 5; a fume exhaust pipe 6; and a water circulating circuit 7 defined by substantially circular-section pipes. Unit 2 is substantially cylindrical, extends along a substantially horizontal axis A1, and comprises a casing 8 through which the fumes flow; a finned pipe 9 along which water flows; and a disk 10 for imposing a given fume flow path inside casing 8. Exchanger 4 substantially comprises pipe 9 and casing 8, which also acts as a combustion chamber for burner 3 housed inside casing 8. Casing 8 comprises a cylindrical lateral wall 11 of axis A1; a cover 12 connected to lateral wall 11, to pipe 5, and to burner 3; and a cover 13 connected to lateral wall 11 and to exhaust pipe 6. Covers 12 and 13 have respective openings 14 and 15, through which the ends of pipe 9 are inserted for connection to circuit 7.
  • Burner 3 extends coaxially with casing 8 and for a given length inside cylindrical lateral wall 11, while pipe 9 forms a coil about an axis A2 substantially coincident with axis A1, and comprises a succession of adjacent turns 16, each located close to lateral wall 11.
  • Exchanger 4 also comprises three comb-like spacers 17 (only one shown in Figure 1) for keeping turns 16 a given distance apart and for keeping the whole of coiled pipe 9 at a given distance from lateral wall 11. Pipe 9, disk 10, and spacers 17 define inside casing 8 a first central region housing burner 3; a second central region communicating directly with the exhaust pipe; and three lateral regions, each extending between two adjacent spacers 17, turns 16, and lateral wall 11. Combustion of the air-gas mixture takes place in the first central region. The combustion fumes are prevented by disk 10 from flowing directly into the second central region, and flow between turns 16, in a direction D1 substantially perpendicular to axis A1, into the three lateral regions, along which they flow in a direction D2 substantially parallel to axis A1. Once inside the lateral regions, the fumes flow between turns 16 in direction D1 into the second central region and then along exhaust pipe 6.
  • Pipe 9, which is preferably made of aluminium or aluminium alloy, is formed from an extruded pipe length 18 extending along a straight axis A3, as shown in Figure 2. Pipe length 18 is cut to a length L1 from which to form pipe 9, and comprises a wall 19; two fins 20 on one side of pipe length 18; two fins 21 on the opposite side to fins 20; a fin 22 between fins 20; and a fin 23 between fins 21. The cross section of pipe length 18 is substantially oval, and has a major axis X and a minor axis Y. Fins 20, 21, 22, 23 are all co-extruded with wall 19, are parallel to axis A3 and major axis X, and are therefore parallel to one another. Fins 22 and 23 are coplanar, and lie substantially in the same plane as axis A2 and major axis X. Fins 20 and 21, on the other hand, are located so that each fin 20 is coplanar with an opposite fin 21, and wall 19 of pipe length 18 forms a slight bulge between the coplanar fins 20 and 21. The maximum extension of fins 20 and 21, in a direction parallel to major axis X, is roughly equal to a quarter of the length of major axis X.
  • With reference to Figure 3, once extruded with respective fins 20, 21, 22, 23 and cut to length L1, pipe length 18 is machined to remove fins 20, 21, 22, 23 from two opposite end portions 18a of pipe length 18, to a given length L2 (only one end portion 18a of pipe length 18 is shown in Figures 2 to 10).
  • With reference to Figures 4 and 5, pipe length 18 is then coiled about an axis A2, so that axis A3 of pipe length 18 is also coiled. This operation, in other words, comprises calendering pipe length 18, while maintaining minor axis Y of the cross section of pipe length 18 substantially parallel to axis A2. The relatively small size of fins 20, 21, 22, 23 does not hinder the calendering operation, and is such that no cutting of fins 20, 21, 22, 23 is required.
  • With reference to Figures 6 and 7, end portions 18a are bent square so that two endpieces 18b of end portions 18a are parallel to axis A2.
  • With reference to Figures 8 and 9, each endpiece 18b is worked mechanically to deform it permanently and transform its cross section from substantially oval to circular up to a length L3 smaller than length L2. This is done by placing each endpiece 18b inside a known variable-section die (not shown), and forcing a punch 24 inside endpiece 18b.
  • With reference to Figure 10, a bevel 25 is worked mechanically on the outer portion of wall 19 and at the opposite ends of pipe length 18 to remove any flaws or surplus material, thus forming pipe 9 from pipe length 18.
  • The three spacers 17 are then fitted between fins 21 of adjacent turns 16 and spaced 120 degrees apart to form, with pipe 9, an assembly which is inserted inside cylindrical wall 11 of casing 8. By virtue of spacers 17, axis A2 substantially coincides with axis A1, and turns 16 are maintained a substantially constant distance from wall 11 (Figure 1). Covers 12 and 13 are then fitted onto the opposite ends of cylindrical wall 11, and endpieces 18b of pipe 9 are inserted inside openings 14 and 15.
  • The coil of pipe 9 is of constant pitch and radius, so that fins 20 and 21 of each turn 16 face and are parallel to fins 20 and 21 of the adjacent turns 16, as shown in Figure 1. Between adjacent turns 16, a gap is thus formed, which is of constant width at fins 20 and 21, and narrows at the bulge in wall 19. In other words, by virtue of disk 10, the successive gaps form compulsory fume paths, and, because of their shape, produce a venturi effect, which brings about a sharp acceleration in fume flow and increases turbulence to improve heat exchange. As such, fins 20 and 21 provide for both increasing the exchange surface of pipe 9 and accelerating fume flow and turbulence.
  • With reference to Figure 11, number 26 indicates two clamps for securing covers 12 and 13 to cylindrical lateral wall 11. Each clamp 26 comprises an automatic fastener 27 (shown open in Figure 12), and has a C-shaped cross section, as shown in Figure 11. With reference to Figure 11, wall 11 comprises two annular ribs 28 at opposite ends. Each cover 12, 13 comprises a portion 29 insertable inside cylindrical lateral wall 11; and an outer portion 30 comprising an annular rib 31, which rests against respective rib 28 to form a seat housing a seal. Each two ribs 28 and 31 are held together by one of clamps 26.
  • With reference to Figure 13, opening 15 (and likewise opening 14) is defined by a sleeve 33, the outer end of which has an internal thread. Circuit 7 is connected to unit 2 by means of ring nuts 34, each of which is axially integral with circuit 7, is threaded externally to screw onto sleeve 33, and has a seat 35 housing a seal 36.
  • In other words, casing 8 communicates externally to exhaust the fumes, to receive gas and air, and to transfer water solely through covers 12 and 13.
  • Exchanger 4 as described above may also be used in condensation boilers featuring a main exchanger, and wherein exchanger 4 provides solely for condensing the fumes, and does not act as a combustion chamber, as in the example described.
  • Fins 20, 21, 22, 23 provide for increasing both heat exchange and turbulence, and, being parallel to axis A3 of the pipe length, can be extruded easily and, at the same time, can be machined off easily to form fittings.

Claims (22)

  1. A method of producing a gas boiler (1) equipped with a water/fume heat exchanger (4) comprising a casing (8), which extends along a first axis (A1), through which fumes flow, and which is connected to a water circulating circuit (7); and a pipe (9), which is coiled about a second axis (A2), has fins (20, 21, 22, 23), conducts water, and is housed inside said casing (8); the method being characterized by cutting a straight pipe length (18) of a length equal to a first length (L1) to form said pipe (9), said pipe length (18) extending along a third axis (A3) and having said fins (20, 21, 22, 23) along the whole of said first length (L1); and removing said fins (20, 21, 22, 23) from opposite end portions (18a) of said pipe length (18); each end portion (18a) extending to a second length (L2).
  2. A method as claimed in Claim 1, characterized in that said pipe length (18) is extruded; said fins (20, 21, 22, 23) being co-extruded with said pipe length (18) and parallel to said third axis (A3).
  3. A method as claimed in Claim 1 or 2,
    characterized by machining off said fins (20, 21, 22, 23).
  4. A method as claimed in any one of the foregoing Claims, characterized by coiling said pipe length (18) about said second axis (A2).
  5. A method as claimed in Claim 4, characterized by bending each end portion (18a) squarely so that an endpiece (18b) of said end portion (18a) is parallel to said second axis (A2).
  6. A method as claimed in any one of the foregoing Claims, characterized in that said pipe length (18) has a substantially oval cross section; the method comprising deforming each end portion (18a) permanently to impart a circular shape to the cross section at opposite ends and to a third length (L3).
  7. A method as claimed in Claim 6, characterized by deforming said end portions (18a) by means of a punch (24) forced into said end portions (18a) to said third length (L3).
  8. A method as claimed in any one of the foregoing Claims, characterized in that said pipe length (18) comprises a wall (19); the method comprising forming an outer bevel (25) on said wall (19) at the ends of the pipe length (18).
  9. A method as claimed in Claim 8, characterized in that said casing (8) comprises a cylindrical lateral wall (11), a first cover (12), and a second cover (13); the method comprising inserting the coiled pipe (9) inside said cylindrical lateral wall (11), and closing said casing (8) by means of the first and second cover (12, 13).
  10. A method as claimed in Claim 9, characterized by fixing the first and second cover (12, 13) to said cylindrical lateral wall (11) by means of respective clamps (26).
  11. A method as claimed in Claim 9 or 10,
    characterized in that the first and second cover (12, 13) have respective openings (14, 15); the method comprising inserting said end portions (18a) at least partly inside said openings (14, 15).
  12. A method as claimed in any one of the foregoing Claims, characterized by connecting each of said end portions (18a) to the water circulating circuit (7) by means of a coupling.
  13. A method as claimed in Claim 1, characterized in that said casing (8) comprises a cylindrical lateral wall (11), and two covers (12, 13) at opposite ends of the cylindrical lateral wall (11); said casing (8) communicating with the outside to exhaust the fumes, to receive gas and air, and to transfer water solely through said covers (12, 13).
  14. A gas boiler (1) equipped with a water/fume heat exchanger (4) connected to a water circulating circuit (7); the boiler comprising a casing (8), which extends along a first axis (A1) and through which fumes flow; and a pipe (9), which is coiled about a second axis (A2), has fins (20, 21, 22, 23), conducts water, and is housed inside said casing (8); the gas boiler being characterized in that said pipe (9) is formed from a straight pipe length (18) extending along a third axis (A3) and having said fins (20, 21, 22, 23) along the whole of its length equal to a first length (L1); said fins (20, 21, 22, 23) being removed from opposite end portions (18a) of said pipe length (18); and each end portion (18a) extending to a second length (L2).
  15. A boiler as claimed in Claim 14, characterized in that said pipe length (18) is extruded; said fins (20, 21, 22, 23) being co-extruded with said pipe length (18) and parallel to said third axis (A3).
  16. A boiler as claimed in Claim 14 or 15,
    characterized in that said pipe (9) has a substantially oval cross section, with the exception of two endpieces (18b), along which two respective end parts have a substantially circular cross section.
  17. A boiler as claimed in Claim 16, characterized in that said endpieces (18b) are parallel to said second axis (A2).
  18. A boiler as claimed in any one of Claims 14 to 17, characterized in that said casing (8) comprises a cylindrical lateral wall (11), and a first and second cover (12, 13) at opposite ends of said cylindrical lateral wall (11); the pipe (9) being housed inside said cylindrical lateral wall (11) and supported by spacers (17) so that the first axis (A1) substantially coincides with the second axis (A2).
  19. A boiler as claimed in Claims 17 and 18, characterized in that said covers (12, 13) have respective openings (14, 15); said endpieces (18b) being inserted inside said openings (14, 15).
  20. A boiler as claimed in Claim 19, characterized in that each cover (12; 13) comprises a sleeve (33) defining a respective opening (14, 15); said sleeve (33) having an internal thread cooperating with a ring nut (34) axially integral with the water circulating circuit (7).
  21. A boiler as claimed in one of Claims 18 to 20, characterized in that said covers (12, 13) are fixed to said cylindrical lateral wall (11) by means of respective clamps (26).
  22. A boiler as claimed in Claim 21, characterized in that said cylindrical lateral wall (11) comprises two first annular ribs (28) at its opposite ends; and said covers (12, 13) comprise respective second annular ribs (31) secured to the first annular ribs (28) by means of said clamps (26); each clamp (26) having a C-shaped cross section for housing a first and a second annular rib (28, 31).
EP05104398A 2004-05-25 2005-05-24 Method of producing a gas boiler, and gas boiler so produced Active EP1600708B8 (en)

Priority Applications (1)

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PL05104398T PL1600708T3 (en) 2004-05-25 2005-05-24 Method of producing a gas boiler, and gas boiler so produced

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT001044A ITMI20041044A1 (en) 2004-05-25 2004-05-25 METHOD OF REALIZATION OF A GAS BOILER AND GAS BOILER SO OBTAINED
ITMI20041044 2004-05-25

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EP1600708A1 true EP1600708A1 (en) 2005-11-30
EP1600708B1 EP1600708B1 (en) 2011-04-13
EP1600708B8 EP1600708B8 (en) 2011-08-10

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EP (1) EP1600708B8 (en)
CN (1) CN100458303C (en)
AT (1) ATE505692T1 (en)
DE (1) DE602005027420D1 (en)
ES (1) ES2364557T3 (en)
IT (1) ITMI20041044A1 (en)
PL (1) PL1600708T3 (en)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080219086A1 (en) * 2007-03-09 2008-09-11 Peter Mathys Apparatus for the heat-exchanging and mixing treatment of fluid media
CN100449220C (en) * 2007-03-06 2009-01-07 成都前锋热交换器有限责任公司 Condensing heat exchanger
WO2010140174A1 (en) 2009-06-05 2010-12-09 Riello S.P.A. Gas boiler, in particular condensation gas boiler for producing hot water
US8028746B2 (en) 2007-02-05 2011-10-04 Elbi International S.P.A. Heat exchanger with finned tube and method of producing the same
EP2375183A1 (en) 2010-04-08 2011-10-12 Riello S.p.A. Heat exchanger for heating at least two fluids and method of producing such a heater
ITMI20100626A1 (en) * 2010-04-13 2011-10-14 Riello Spa HEAT EXCHANGER TO HEAT A LIQUID BY COMBUSTION SMOKES
WO2011128764A1 (en) 2010-04-13 2011-10-20 Riello S.P.A. Method of producing a heat exchanger, and heat exchanger produced using such a method
DE102011016565A1 (en) 2010-04-08 2011-12-01 Riello S.P.A. Heat exchanger i.e. condensation-type heat exchanger, for use in condensing boiler for preparing e.g. domestic hot water, has hollow element comprising supporting structure and coating, which is made of material that contacts with water
ITMI20101505A1 (en) * 2010-08-05 2012-02-06 Riello Spa HEAT EXCHANGER PROVIDED WITH A THERMO-PHOTOVOLTAIC DEVICE
ITMI20101729A1 (en) * 2010-09-23 2012-03-24 Riello Spa CONDENSING HEAT EXCHANGER FOR A GAS BOILER
CN105650636A (en) * 2016-02-03 2016-06-08 浙江广涛卫厨有限公司 Heat exchanger assembly for burner
ITUB20153466A1 (en) * 2015-09-08 2017-03-08 Riello Spa HEAT EXCHANGER FOR A DOMESTIC BOILER OR A WATER HEATER
EP3141839A1 (en) 2015-09-08 2017-03-15 Riello S.p.A. Heat exchanger for heating water in a domestic boiler or a water heater
EP3141840A1 (en) 2015-09-08 2017-03-15 Riello S.p.A. Heat exchanger for a domestic boiler or a water heater
IT201800010317A1 (en) * 2018-11-14 2020-05-14 Condevo S P A THERMAL EXCHANGE CELL
EP3770528A3 (en) * 2016-07-18 2021-05-05 Valmex S.p.A. Heat exchanger for boiler

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DE20209753U1 (en) * 2001-06-25 2002-10-24 Vaillant Gmbh Heater with a combustion chamber
EP1279903A2 (en) * 2001-07-26 2003-01-29 Robert Bosch Gmbh Heat exchanger for a gas heater, esp. for a condensing boiler
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Cited By (21)

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Publication number Priority date Publication date Assignee Title
US8028746B2 (en) 2007-02-05 2011-10-04 Elbi International S.P.A. Heat exchanger with finned tube and method of producing the same
CN100449220C (en) * 2007-03-06 2009-01-07 成都前锋热交换器有限责任公司 Condensing heat exchanger
US20080219086A1 (en) * 2007-03-09 2008-09-11 Peter Mathys Apparatus for the heat-exchanging and mixing treatment of fluid media
US8794820B2 (en) * 2007-03-09 2014-08-05 Sulzer Chemtech Ag Apparatus for the heat-exchanging and mixing treatment of fluid media
WO2010140174A1 (en) 2009-06-05 2010-12-09 Riello S.P.A. Gas boiler, in particular condensation gas boiler for producing hot water
EP2375183A1 (en) 2010-04-08 2011-10-12 Riello S.p.A. Heat exchanger for heating at least two fluids and method of producing such a heater
DE102011016565A1 (en) 2010-04-08 2011-12-01 Riello S.P.A. Heat exchanger i.e. condensation-type heat exchanger, for use in condensing boiler for preparing e.g. domestic hot water, has hollow element comprising supporting structure and coating, which is made of material that contacts with water
ITMI20100626A1 (en) * 2010-04-13 2011-10-14 Riello Spa HEAT EXCHANGER TO HEAT A LIQUID BY COMBUSTION SMOKES
WO2011128764A1 (en) 2010-04-13 2011-10-20 Riello S.P.A. Method of producing a heat exchanger, and heat exchanger produced using such a method
ITMI20101505A1 (en) * 2010-08-05 2012-02-06 Riello Spa HEAT EXCHANGER PROVIDED WITH A THERMO-PHOTOVOLTAIC DEVICE
EP2434227A2 (en) 2010-09-23 2012-03-28 Riello S.p.A. Condensing heat exchanger for a gas boiler
ITMI20101729A1 (en) * 2010-09-23 2012-03-24 Riello Spa CONDENSING HEAT EXCHANGER FOR A GAS BOILER
EP2434227A3 (en) * 2010-09-23 2014-08-20 Riello S.p.A. Condensing heat exchanger for a gas boiler
ITUB20153466A1 (en) * 2015-09-08 2017-03-08 Riello Spa HEAT EXCHANGER FOR A DOMESTIC BOILER OR A WATER HEATER
EP3141839A1 (en) 2015-09-08 2017-03-15 Riello S.p.A. Heat exchanger for heating water in a domestic boiler or a water heater
EP3141840A1 (en) 2015-09-08 2017-03-15 Riello S.p.A. Heat exchanger for a domestic boiler or a water heater
EP3141841A1 (en) 2015-09-08 2017-03-15 Riello S.p.A. Heat exchanger for a domestic boiler or a water heater
CN105650636A (en) * 2016-02-03 2016-06-08 浙江广涛卫厨有限公司 Heat exchanger assembly for burner
EP3770528A3 (en) * 2016-07-18 2021-05-05 Valmex S.p.A. Heat exchanger for boiler
CN113375334A (en) * 2016-07-18 2021-09-10 瓦勒麦克股份公司 Heat exchanger for boiler
IT201800010317A1 (en) * 2018-11-14 2020-05-14 Condevo S P A THERMAL EXCHANGE CELL

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ES2364557T3 (en) 2011-09-06
DE602005027420D1 (en) 2011-05-26
CN1702396A (en) 2005-11-30
PL1600708T3 (en) 2011-10-31
ITMI20041044A1 (en) 2004-08-25
EP1600708B1 (en) 2011-04-13
EP1600708B8 (en) 2011-08-10
ATE505692T1 (en) 2011-04-15

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