Galvanizing Furnace

Abstract

A galvanizing furnace (1) with a galvanizing vat (6) and a furnace housing (2) surrounding the galvanizing vat (6), which furnace housing has a rectangular cross-section. The furnace housing (2) has two opposite longitudinal sidewalls (4) and two opposite end walls (5) and further comprises burners for heating molten zinc in the galvanizing vat (6). In the areas of two diagonally opposite corners of the furnace housing (2), at least one first receptacle (15) is provided for a burner. In the areas of the other two diagonally opposite corners of the furnace housing (2), a second receptacle (16) is provided for a burner. The burners are arranged optionally either in the first receptacles (15) or in the second receptacles (16). Flames produced by the burners are conducted in the area between a longitudinal sidewall (4) of the furnace housing (2) and the opposite wall of the galvanizing vat (6).

Claims

1. A galvanizing furnace (1) with a galvanizing vat (6) and a furnace housing (2) having a rectangular cross section surrounding the galvanizing vat (6), wherein the furnace housing (2) has two opposite longitudinal sidewalls (4) and two opposite end walls (5), and with burners for heating of molten zinc in the galvanizing vat (6), characterized in that in the areas of two diagonally opposite corners of the furnace housing (2) in each case at least one first receptacle (15) for a burner is provided, that in the areas of the two other diagonally opposite corners of the furnace housing (2) in each case a second receptacle (16) for a burner is provided, and that burners are optionally arranged either in the first receptacles (15) or in the second receptacles (16), wherein flames produced by the burners are conducted in each case in the area between a longitudinal sidewall (4) of the furnace housing (2) and the opposite wall of the galvanizing vat (6).

2. The galvanizing furnace according to claim 1, characterized in that means for location-dependent detection of the wear of the walls of the galvanizing vat (6) are provided, and that depending on the wear data determined, a change of the burners from the first receptacles (15) to the second receptacles (16) can be carried out, or vice versa.

3. The galvanizing furnace according to claim 1, characterized in that as a measure for the wear of the walls of the galvanizing vat (6) its wall thickness is measured.

4. The galvanizing furnace according to claim 1, characterized in that in the area of the flame ejection of at least one burner the actual wall thickness of the galvanizing vat (6) is measured, and that a change of the burners is performed when the actual wall thickness drops below a specified limit value.

5. The galvanizing furnace according to claim 1, characterized in that an ultrasonic transducer is provided for measuring the wall thickness of the galvanizing vat (6).

6. The galvanizing furnace according to claim 5, characterized in that closable inspection openings (19) are provided in the longitudinal sidewalls (4) of the furnace housing (2), wherein the ultrasonic transducer is inserted through an inspection opening (19) to the outside of a wall of the galvanizing vat (6) in order to measure the wall thickness.

7. The galvanizing furnace according to claim 1, characterized in that the receptacles (15, 16) for the burners are in each case arranged in an end wall (5), and/or that in every corner area of the furnace housing (2) multiple receptacles (15, 16) are provided in each of which a burner can be arranged.

8. The galvanizing furnace according to claim 1, characterized in that all receptacles (15, 16) are designed identically.

9. The galvanizing furnace according to claim 1, characterized in that the receptacles (15, 16), in which no burner is arranged, are tightly sealed with sealing means (18).

10. The galvanizing furnace according to claim 1, characterized in that the burners are formed by high-speed burners (14).

11. The galvanizing furnace according to claim 1, characterized in that the galvanizing vat (6) has an essentially rectangular cross-section that is adapted to the cross-section of the furnace housing (2), and that in every corner area of the galvanizing vat (6) a flame deflector plate (17) is attached on the outside wall of the galvanizing vat (6).

12. The galvanizing furnace according to claim 11, characterized in that inspection openings (19) are provided in the longitudinal sidewalls (4) of the furnace housing (2), such that the ultrasonic transducer passed through such an inspection opening (19) is guided directly onto a flame deflector plate (17) adjacent to a wall of the galvanizing vat (6).

13. The galvanizing furnace according to claim 1, characterized in that first temperature sensors (12) are integrated in braces (10), which support a wall of the galvanizing vat (6) against a longitudinal sidewall (4) of the furnace housing (2), and/or that second temperature sensors (13) are provided for measuring the temperature in the interior of the furnace housing (2).

14. The galvanizing furnace according to claim 13, characterized in that the outputs of the burners are adjusted depending on the measured values obtained with the first or second temperature sensors (12, 13).

15. A method for operating a galvanizing furnace (1) with a galvanizing vat (6) and a furnace housing (2) surrounding the galvanizing vat (6), which furnace housing has a rectangular cross-section, wherein the furnace housing (2) has two opposite longitudinal sidewalls (4) and two opposite end walls (5), and with burners for heating of molten zinc in the galvanizing vat (6), characterized in that in the areas of two diagonally opposite corners of the furnace housing (2) in each case at least one first receptacle (15) for a burner is provided, that in the areas of the two other diagonally opposite corners of the furnace housing (2) in each case a second receptacle (16) for a burner is provided, and that burners are arranged optionally either in the first receptacles (15) or in the second receptacles (16), wherein in each case flames produced by the burners are conducted in the area between a longitudinal sidewall (4) of the furnace housing (2) and the opposite wall of the galvanizing vat (6).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In the following, the invention is explained with the aid of drawings, showing:

[0054] FIG. 1: A longitudinal sectional view of an embodiment of the galvanizing furnace according to the invention.

[0055] FIG. 2: A cross-sectional view of the galvanizing furnace according to FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0056] FIGS. 1 and 2 illustrate an embodiment of the galvanizing furnace 1 according to the invention. The galvanizing furnace 1 has a furnace housing 2 with a floor 3 having a rectangular contour and in each case two longitudinal sidewalls 4 and two end walls 5 protruding perpendicularly from the floor 3, wherein the two end walls 5 are arranged opposite each other and the longitudinal sidewalls 4 are arranged opposite each other. The furnace housing 2 therefore has a constant rectangular cross-section over its entire height.

[0057] In the interior of the furnace housing 2, a galvanizing vat 6 is located which serves for holding molten zinc to be heated. The galvanizing vat 6 has an essentially rectangular cross-section adapted to the cross-section of the furnace housing 2, so that the sidewalls 7 of the galvanizing vat 6 are arranged at a constant distance to the longitudinal sidewalls 4 and end walls 5 of the furnace housing 2. The galvanizing vat 6 has a planar floor 8, which rests on the floor 3 of the furnace housing 2.

[0058] The upper edge of the galvanizing vat 6 is accommodated in an edge segment 9 of the furnace housing 2, which edge segment extends on the top sides of the longitudinal sidewalls 4 and of the end walls 5. The open top side of the galvanizing vat 6 can be closed with a cover [not illustrated].

[0059] The galvanizing vat 6 is supported with braces 10 against the inner sides of the longitudinal sidewalls 4 of the furnace housing 2. The braces 10 thus form a clamping frame for fixing the position of the galvanizing vat 6 in the furnace housing 2.

[0060] One end wall 5 has a flue gas discharge orifice, which is designed in the form of a flange 11 with an exhaust gas flap 11a. The spatial pressure of the furnace atmosphere is controlled via the exhaust gas flap 11a, in order to obtain an effective temperature transition to the galvanizing vat 6.

[0061] First temperature sensors 12 for measuring the temperatures in the braces 10 themselves are provided in or on the braces 10. Overheating of the braces 10 can be monitored in this way.

[0062] Furthermore, second temperature sensors 13 are located in the area of the inner sides of the sidewalls 7, for measuring the temperature in the interior of the furnace housing 2.

[0063] The first and second temperature sensors 12, 13 are advantageously in the form of thermocouples. Depending upon the measured values generated with the temperature sensors 12, 13, the heat output of the galvanizing furnace 1, and thus the temperature in the interior of the furnace housing 2, can be controlled.

[0064] The interior of the furnace housing 2 is heated by means of burners. The burners are designed as gas burners, namely in the present case as high-speed burners 14.

[0065] To support the high-speed burners 14, according to the invention first receptacles 15 are incorporated into the respective end wall 5 in two diagonally opposite corner areas of the furnace housing 2. Furthermore, second receptacles 16 are incorporated into the respective end wall 5 in the two other diagonally opposite corner areas of the furnace housing 2.

[0066] The first and second receptacles 15, 16 are designed identically and are matched to the physical size of the high-speed burners 14, so that the high-speed burners 14 can optionally be installed in first or second receptacles 15, 16.

[0067] FIG. 2 illustrates a receptacle 15, 16 in each corner area. In principle, multiple identical first receptacles 15 or second receptacles 16 can be arranged spaced apart above each other in each corner area, so that a high-speed burner 14 can be supported in each of these receptacles 15, 16 of a corner area.

[0068] According to the invention, the high-speed burners 14 are inserted either only in the first receptacles 15 or in the second receptacles 16, in order to heat the interior of the furnace housing 2 in this way.

[0069] Because the high-speed burners 14 can be installed in every corner area of the furnace housing 2, as shown in FIGS. 1 and 2, the outside walls of the galvanizing vat 6 are clad in all corner areas with flame deflector plates 17, in order to protect the walls of the galvanizing vat 6 against the flames emerging from the high-speed burners 14. The identically designed flame deflector plates 17 extend across the entire height of the galvanizing vat 6.

[0070] In the configuration illustrated in FIG. 2, the high-speed burners 14 are arranged in the first receptacles 15. The second receptacles 16, in which no high-speed burners 14 exist, are tightly sealed with sealing means 18, so that the furnace walls are tightly encapsulated. The sealing means 18 can in each case be formed from furnace insulation material and a cover plate.

[0071] If the galvanizing furnace 1 is operated with the burner configuration according to FIG. 2, the flames of the high-speed burner 14 are in each case conducted in the interspaces between a longitudinal sidewall 4 of the furnace housing 2 and a wall of the galvanizing vat 6, and as a result the molten zinc in the vat is heated.

[0072] According to the type of installation of the high-speed burners 14 in the first receptacles 15, the flame temperature is highest in the discharge area of the high-speed burner 14 (designated A in FIG. 2) and then decreases continuously towards the area at the other end of the furnace housing 2 (designated B in FIG. 2).

[0073] Accordingly, during the operation of the galvanizing furnace 1 with the burner configuration according to FIG. 2, the highest wear of the galvanizing vat 6 occurs in area A, which wear consists of a reduction of the wall thickness of the galvanizing vat 6. The reduction of the wall thickness then decreases continuously from area A to area B.

[0074] During the operation of the galvanizing furnace 1, the reduction of the wall thickness due to wear is preferably recorded metrologically at regular time intervals.

[0075] For this purpose, identical configurations of inspection openings 19 are incorporated into the longitudinal sidewalls 4 of the furnace housing 2, which inspection openings can be closed with covers (not illustrated separately).

[0076] Ultrasonic transducers (not shown) are provided for carrying out non-contact measurement of the wall thickness of the galvanizing vat 6 during the operation of the galvanizing furnace 1. To carry out such measurement, the cover is removed from an inspection opening 19, and the ultrasonic transducer is then inserted through the inspection opening 19 to the wall of the galvanizing vat 6, where the ultrasonic transducer preferably adheres by means of an integrated magnet in a defined measuring position on the wall of the galvanizing vat 6.

[0077] As can be seen from FIG. 1, four rows of inspection openings 19 are provided, with in each case three inspection openings 19 arranged one above the other. The two outer rows are arranged directly following the flame deflector plates 17. Furthermore, two central rows of inspection openings 19 are provided.

[0078] By inserting ultrasonic transducers through the inspection openings 19, the wall thickness of the galvanizing vat 6 can be detected and spatially resolved, while the galvanizing furnace 1 is being operated. In particular, by inserting the ultrasonic transducers through the left-hand row of inspection openings 19, the wall thickness of the galvanizing vat 6 can be measured in area A, where the greatest wear of the galvanizing vat 6 is encountered.

[0079] In particular, when it is determined in this critical area A that the wall thickness of the galvanizing vat 6 has dropped below a critical value, the mounting locations of the high-speed burners 14 are preferably exchanged during the next maintenance period of the galvanizing furnace 1 such that the high-speed burners 14 are dismantled from the first receptacles 15 and are then installed in the second receptacles 16. The first receptacles 15 are then appropriately sealed with the sealing means 18.

[0080] Because in the subsequent operation of the galvanizing furnace 1 the high-speed burners 14 are now installed in the second receptacles 16, the areas B are then subjected to the greatest wear. The areas A, which were still subjected to heavy wear during the first operating phase are protected, however, since the flame temperatures of the high-speed burners 14 are now lower at those points. Therefore, in spite of the heavy wear that occurred in the galvanizing vat 6 in the areas A during the first phase, the galvanizing furnace 1 can continue to be operated without risk of damage, because in the second phase only slight wear still occurs in the areas A with the high-speed burners 14 being arranged in the second receptacles 16. The galvanizing furnace 1 can therefore continue to be operated without risk of damaging the galvanizing vat 6, until a reduction in the wall thickness in the areas B of the galvanizing vat 6 also occurs up to the limit value. In this context, the wall thickness of the galvanizing vat 6 is checked again by the measurements carried out with the ultrasonic transducers. This significantly increases the service life of the galvanizing furnace 1 with the galvanizing vat 6, compared with an operation in which the high-speed burners 14 are permanently arranged only in the first receptacles 15.

LIST OF REFERENCE NUMERALS

[0081] (1) Galvanizing furnace [0082] (2) Furnace housing [0083] (3) Floor [0084] (4) Longitudinal sidewall [0085] (5) End wall [0086] (6) Galvanizing vat [0087] (7) Sidewall [0088] (8) Vat floor [0089] (9) Edge segment [0090] (10) Brace [0091] (11) Flanges [0092] (11a) Exhaust gas flap [0093] (12) First temperature sensor [0094] (13) Second temperature sensor [0095] (14) High-speed burner [0096] (15) First receptacle [0097] (16) Second receptacle [0098] (17) Flame deflector plate [0099] (18) Sealing means [0100] (19) Inspection opening Claims