System with a spraying nozzle unit and method for spraying an inorganic mass

Abstract

A system for applying an inorganic coating material to a surface (110) comprising: —a spray nozzle unit (50), having the following features: —a first end portion (51) with a first connection (11) for a first supply hose (10), for supplying a first component of the coating material, —a second end portion (52) for discharging the coating material from the spray nozzle unit (50), —a connection unit (60) for mixing and transporting components of the coating material from the first end portion (51) to the second end portion (52), —wherein the connection unit (60) comprises a mixing chamber (61) with at least one further connection (21,31) for supplying a second component of the coating material, —and wherein at least one electronic sensor (70) is mounted on the connection unit (60), to detect an oscillation amplitude (81) arising at the connection unit (60), —a data processing unit (80), —a comparison unit (90), —a control unit (100), wherein the control unit (100) —generates a warning signal (101) when the control data (91) lie above a predetermined limit value, and/or—varies the volume flow (102) of at least one of the components of the coating material depending on the control data (91) is generated by the comparison unit (90). As well as methods for applying an organic coating material obtained by mixing a plurality of components in a spray nozzle unit (50).

Claims

1. System for applying an inorganic coating material to a surface (110), the system comprising: a spray nozzle unit (50) comprising: a first end portion (51), wherein a first connection (11) for a first supply hose (10) is coupled to the first end portion (51) of the spray nozzle unit (50), the first supply hose is for supplying a first component of the inorganic coating material, a second end portion (52) having an open end, wherein the inorganic coating material is discharged from the spray nozzle unit (50) from the open end of the second end portion (52), and a connection unit (60) for mixing components of the inorganic coating material and transporting the inorganic coating material from the first end portion (51) to the second end portion (52), the connection unit (60) positioned in the spray nozzle unit (50) between the first end portion (51) and the open end of the second end portion (52) of the spray nozzle unit (50), wherein the connection unit (60) comprises a mixing chamber (61), wherein the mixing chamber (61) has a second connection (21, 31) for a second supply hose that is coupled to the mixing chamber (61), wherein the second supply hose is for supplying a second component of the coating material to the mixing chamber (61), a manipulator that is mechanically coupled to the spray nozzle unit (50), wherein the manipulator is configured to move the spray nozzle unit (50) relative to an inner surface of a metallurgical vessel to allow for coating of the inner surface of the metallurgical vessel with the inorganic coating material, wherein at least one electronic sensor (70) is mounted on the connection unit (60) to detect an oscillation amplitude (81) arising at the connection unit (60), a data processing unit (80) for acquiring the oscillation amplitude (81) detected by the electronic sensor (70) of the spray nozzle unit (50) and for calculating an actual frequency spectrum (82) or target frequency spectrum (82) from the oscillation amplitudes (81) detected, a comparison unit (90) for comparing the actual frequency spectrum (82) with a target frequency spectrum (82) and generating control data (91), and a control unit (100), wherein the control unit (100) generates a warning signal (101) when the control data (91) lie outside a defined range, and/or varies the volume flow (102) of at least one of the components of the coating material depending on the control data (91) generated by the comparison unit (90).

2. System according to claim 1, characterized in that the comparison unit (90) determines actual frequency components (92) and/or target frequency components (92) by summing the respective frequency amplitude values (93) from the actual frequency spectrum (82) and/or the target frequency spectrum (82) over a defined frequency range.

3. System according to claim 1, characterized in that the comparison unit (90) generates control data (91) from the weighted summation of the deviations or quotients between the actual frequency components (92) and the target frequency components (92).

4. System according to claim 1, characterized in that the connection unit (60) comprises a pipe (62) connected to the mixing chamber (61), wherein the sensor (70) is mounted on the pipe (62).

5. System according to claim 1, characterized in that the sensor (70) is a piezo-electric acceleration sensor.

6. System according to claim 1, characterized in that the sensor (70) is integrated into a clamp which surrounds the connection unit (60).

7. System according to claim 1, characterized in that the connection unit (60) between the first end portion (51) and the open end of the second end portion (52) of the spray nozzle unit builds a substantially step-free and kink-free path.

8. System according to claim 1, wherein the sensor outputs values that are indicative of accelerations arising at the connection unit, wherein the accelerations are normal to a surface of the connection unit, and further wherein at least one of the actual frequency spectrum or the target frequency spectrum is computed based upon the values that are indicative of accelerations arising at the connection unit.

9. Method for applying an inorganic coating to an inner surface of a metallurgical vessel, the method comprising the following steps: providing a system, the system comprising: a spray nozzle unit (50) comprising: a first end portion (51), wherein a first connection (11) for a first supply hose (10) is coupled to the first end portion (51) of the spray nozzle unit (50), the first supply hose is for supplying a first component of the inorganic coating material, a second end portion (52) having an open end, wherein the inorganic coating material is discharged from the spray nozzle unit (50) from the open end of the second end portion (52), and a connection unit (60) for mixing components of the inorganic coating material and transporting the inorganic coating material from the first end portion (51) to the second end portion (52), the connection unit (60) positioned in the spray nozzle unit (50) between the first end portion (51) and the open end of the second end portion (52) of the spray nozzle unit (50), wherein the connection unit (60) comprises a mixing chamber (61), wherein the mixing chamber (61) has a second connection (21, 31) for a second supply hose that is coupled to the mixing chamber (61), wherein the second supply hose is for supplying a second component of the coating material to the mixing chamber (61), a manipulator that is mechanically coupled to the spray nozzle unit (50), wherein the manipulator is configured to move the spray nozzle unit (50) relative to the inner surface of the metallurgical vessel to allow for coating of the inner surface of the metallurgical vessel with the inorganic coating material, wherein at least one electronic sensor (70) is mounted on the connection unit (60) to detect an oscillation amplitude (81) arising at the connection unit (60), and a data processing unit (80) for acquiring the oscillation amplitude (81) detected by the electronic sensor (70) of the spray nozzle unit (50) and for calculating an actual frequency spectrum (82) or target frequency spectrum (82) from the oscillation amplitudes (81) detected, a comparison unit (90) for comparing the actual frequency spectrum (82) with a target frequency spectrum (82) and generating control data (91), and a control unit (100), measuring, by the data processing unit, the oscillation amplitude (81) detected by the electronic sensor (70) of the spray nozzle unit (50) during the mixing and transport of the inorganic coating material through the connection unit (60) of the spray nozzle unit (50) calculating, by the data processing unit, the actual frequency spectrum (82), from the measured oscillation amplitudes (81), generating, by the comparison unit, the control data (91) by comparing the actual frequency spectrum (82) with a stored target frequency spectrum (82), as well as generating, by the control unit, a warning signal (101) when the control data (91) lie outside a defined range and/or varying, by the control unit, the volume flow (102) of at least one of the components of the coating material depending on the control data (91) generated by the comparison unit.

10. The method according to claim 9, characterized in that a calculation of actual frequency components (92) or target frequency components (92) is performed for the generation of control data (91) by summation of frequency amplitude values (93) over a specific frequency range of the actual frequency spectrum (82) or target frequency spectrum (82).

11. Method according to claim 9, characterized in that at least one frequency component (92) is calculated in the frequency range of 3000-9300 Hz.

12. Method according to claim 9, characterized in that the control data (91) are generated by the weighted summation of the deviations or quotients between the actual frequency components (92) and the target frequency components (92).

13. Method according to claim 9, characterized in that a target frequency spectrum (82) is obtained by the following steps: setting a target consistency of the coating material by varying the volume flows (102) of the components of the coating material, measuring the oscillation amplitude (81) detected by the electronic sensor (70) of the spray nozzle unit (50), when the coating material is mixed and transported with the target consistency by the connection unit (60) of the spray nozzle unit (50), calculating a target frequency spectrum (82) from the measured oscillation amplitudes (81), and storing the target frequency spectrum (82).

14. Method according to claim 9, characterized in that, further a dry first component of the coating material is provided by the first supply hose (10) to the spray nozzle unit (50) and a liquid second component of the coating material is provided by the second supply hose (20) to the spray nozzle unit (50), wherein the first component and the second component of the coating material are mixed in the spray nozzle unit (50), and the mixed coating material is directed to the second end portion (52) of the spray nozzle unit (50) and there leaves the spray nozzle unit (50) in the direction of the inner surface of the metallurgical vessel to be coated; the mixed coating material then impinges on the inner surface of the metallurgical vessel to be coated and, after drying, forms the coating of the inner surface of the metallurgical vessel.

Description

(1) Exemplary embodiments of the invention are explained in more detail by means of illustrations:

(2) FIG. 1 shows a schematic representation of the spray nozzle unit according to the invention,

(3) FIG. 2 shows a schematic sequence of the method according to the invention,

(4) FIG. 3a and FIG. 3b show an exemplary diagram of quotients of actual frequency components and target frequency components.

EXEMPLARY EMBODIMENT 1

(5) FIG. 1 shows a first supply hose (delivery hose) 10 which conveys the basic mass (Ankerjet NP 12, basic mass, 0-3 mm granulation band, highly refractory), so that the latter passes through the first end portion 51 of the spray nozzle unit 50 to the mixing chamber 61 via the first connection 11. Water passes through the second supply hose 20 into the mixing chamber 61 via the second connection 21. Compressed air reaches the mixing chamber 61 via the third connection 31 via the third supply hose 30. The coating material is formed in the mixing chamber 61 from the components of the basic mass of the Ankerjet NP 12, wherein water and air are mixed and transported through the pipe 62 (length: 2 m) into the nozzle head 63, and then leaves the spray nozzle unit 50 via the second end portion 52 and from there to the surface 110 to be coated. The spray nozzle unit 50 consists of steel. A piezoelectric sensor 70 is form-fittingly connected to the pipe 62 at the center of the pipe 62 (i.e. 1 m distal from the pipe end part adjoining the mixing chamber 61, or 10 times the pipe diameter, the pipe diameter being 10 cm) and detects an oscillation amplitude 81 emerging in the pipe 62, which is acquired by the data processing unit 80. The data processing unit 80 is connected to the comparison unit 90 and controls the control unit 100 through the control data 91 to regulate the through-flow/volume flow 102 of the components by means of a controllable delivery pump (100a) or controllable electrical valves (100b, 100c) of the coating material.

(6) FIG. 2 shows the piezoelectric sensor 70 (here: ICP accelerometer, Model Number 352C33) mounted on the pipe 62 of the connection unit 60, which supplies an analog data signal to the data processing unit 80. The data processing unit 80 in this exemplary embodiment is a computer using the software LabView. The analog data signal is first digitized (16 bits, 51,400 Hz), so that a time-dependent oscillation amplitude 81 is obtained. This is converted continuously into an FFT (Fast Fourier Transformation) module into a frequency spectrum 82, so that frequency amplitude values 93 are obtained (over a time interval of the oscillation amplitude of 250 ms). Three frequency components 92 are continuously calculated from the frequency amplitude values 93 by averaging the frequency amplitude values 93 in a range of 1-2999 Hz (G1 (t)), 3000-9300 Hz (G2 (t)) and 9301-12000 Hz G3 (t)). The values G1 (t), G2 (t) and G3 (t) are calculated for further processing as a moving average over a time interval of 15 seconds. Control data 91 are then calculated from the frequency amplitude values 93, and forwarded to the control unit 100. When a maximum value of the control data 91 is exceeded, the control unit outputs a warning signal 101 and regulates a volume flow 102.

(7) The spray nozzle unit 50 in this exemplary embodiment is a binary nozzle. The dry mass (Ankerjet NP 12) is conveyed via the first supply hose 10 to the first connection 11 of the spray nozzle unit 50 by compressed air (conveying air) provided by a compressor (pressure 6 bar; the mass is introduced into the air flow by the “Ankerjet” machine, wherein the pressure in the air flow is 0.5 bar, the (air) flow rate is about 190 m3/h,). Water is fed directly from the drinking water line by means of a water pump WK155 under a pressure of about 1.5 bar via the second supply hose 20 to the second connection 21. The water volume is adjusted by means of an electrically-controllable valve 100b (the measurement of the exact volume flow of water is carried out by means of a flowmeter from the company Krohne DN 50, PN=40 [bar], Q=0-50 [m3/h], Output I=4-20 [mA]). The compressed air (atomizing air) is fed to the third connection 31 of the spray nozzle unit 50 via the third supply hose 30 at a pressure of 1.5 bar and 50 m.sup.3/h (supplied via a screw compressor from the company KAESER, type BSD 81 T (11.0 [bar] 400 [V])). The spray nozzle unit 50 is aligned horizontally in the direction of a surface 110 to be coated. The surface 110 is aligned at a distance of 3 m from the second end portion (52) of the spray nozzle unit 50 and essentially normal to the axis of the spray nozzle unit 50.

(8) Table 1 shows the test results.

(9) TABLE-US-00001 TABLE 1 list of tests Test Volumeflow volumeflow Water G.sub.1 (t)/G.sub.1 G.sub.2 (t)/G.sub.2 G.sub.3 (t)/G.sub.3 number mass/kg/min water/l/min content/l/kg Result G.sub.1 (t)/m/s.sup.2 G.sub.2 (t)/m/s.sup.2 G.sub.3 (t)/m/s.sup.2 (0)/% (0)/% (0)/% 1 120 6 0.050 Too dry 0.33 1.30 1.22 68% 72% 82% 2 120 9.2 0.077 opt. 0.48 1.80 1.48  100% (*)  100% (*)  100% (*) 3 120 13 0.108 Too wet 0.59 2.20 1.84 122%  122%  124%  4 75 6 0.080 opt. 0.78 1.90 1.40 162%  106%  94% 5 100 6 0.060 Too dry 0.42 1.27 1.04 87% 70% 70% opt. = optimal // (*) reference value

(10) In test number 1, the flow rate of the basic mass is determined to be about 120 kg/min (volume flow). Water is added at 6 l/min (volume flow) (water content 0.050 I/kg of water in the mass). The result is judged to be too dry because partial dust formation occurs and a lot of mass rebounds from the surface 110 to be coated.

(11) In test number 2, the water quantity is increased to 9.2 l/min (water content 0.077 I/kg; mass: 120 kg/min). The result is evaluated as being optimal, since a large part of the mass adheres to the surface 110 to be coated, no dust formation occurs, and the mass does not run off. A target frequency spectrum 82 is calculated from the oscillation amplitude 81 obtained at this optimal water content, and the three target frequency components 92 G.sub.1 (0)=0.48, G.sub.2 (0)=1.80 and G.sub.3 (0)=1.48 calculated therefrom. These obtained values are used as the reference (target frequency components 92) for the remaining examples.

(12) In test number 3, the water quantity is increased to 13 l/min (water content 0.108 I/kg, mass: 120 kg/min). The result is judged to be too wet because the mass partially runs off from the surface 110.

(13) In test number 4, the mass is added at 75 kg/min from a water addition of 6 l/min (water content 0.080, mass: 75 kg/min). The result is evaluated as optimal, since a large part of the mass adheres to the surface 110 to be coated, no dust formation occurs, and the mass does not run off. However, in contrast to the result of test 2, only a reduced volume flow is used.

(14) In test number 5, the mass is added at 100 kg/min from a water addition of 6 l/min (water content 0.060, mass: 100 kg/min). The result is judged to be too dry because partial dust formation occurs and a lot of mass rebounds from the surface to be coated.

(15) The comparison of the target frequency components 92 (G.sub.1 (0), G.sub.2 (0) and G.sub.3 (0)) obtained from test number 2 with the values obtained from the other tests (actual frequency components 92 G.sub.1 (t), G.sub.2 (t) and G.sub.3 (t)) is exemplarily shown by quotient formation (i.e. G.sub.1 (t)/G.sub.1 (0), G.sub.2 (t)/G.sub.2 (0) and G.sub.3 (t)/G.sub.3 (0)).

(16) FIG. 3a shows the curve of the quotient G.sub.1 (t)/G.sub.1 (0) as a function of the water content (as a quotient of added water in l/min to supplied mass in kg/min). In the case of optimal consistency, a large difference is detected in the signal G.sub.1 (t)/G.sub.1 (0) between an overall low volume flow (G.sub.1 (t)/G.sub.1 (0)=162% at a mass M=75 kg/min, water W=6 l/min) and a high volume flow, (G.sub.1 (t)/G.sub.1 (0)=100% [=reference] at a mass M=120 kg/min, water W=9.2 l/min). This value therefore allows the monitoring of a constant volume flow of the dry mass (Ankerjet NP12) in this exemplary embodiment. Control data 91 S(t)=1−G.sub.1 (t)/G.sub.1 (0) may be formed here. When |S(t)|>10%, a warning signal 101 is emitted by outputting a message on a screen.

(17) FIG. 3b shows the course of the quotient G.sub.2 (t)/G.sub.2 (0) as a function of the water content. The quotient G.sub.2 (t)/G.sub.2 (0) shows a good correlation with the water content, independent of the volume flow of the dry mass. This value may therefore be used to control the volume flow of water 102 by setting control data 91 S(t)=1−G.sub.2 (t)/G.sub.2 (0). When S<0, the volume flow of water is decreased by one unit (e.g. 0.1 l/min) by means of the electrically-controllable valve 100b. When S>0, the volume flow of water 102 is increased by one unit. With this regulation, a uniformly good consistency is obtained during long application times.

(18) The curve of the quotient G.sub.3 (t)/G.sub.3 (0) as a function of the water content is qualitatively similar to that of G.sub.2 (t)/G.sub.2 (0) in FIG. 3b, therefore analogous conclusions also apply here.

LIST OF REFERENCE NUMERALS AND FACTORS

(19) 10 First supply hose (conveying hose)

(20) 11 First connection

(21) 20 Second supply hose

(22) 21 Second connection

(23) 30 Third supply hose

(24) 31 Third connection

(25) 50 Spray nozzle unit

(26) 51 First end portion of the spray nozzle unit

(27) 52 Second end portion of the spray nozzle unit

(28) 60 Connection unit

(29) 61 Mixing chamber

(30) 62 Pipe

(31) 63 Nozzle head

(32) 70 Sensor

(33) 80 Data processing unit

(34) 81 Oscillation amplitude

(35) 82 Frequency Spectrum

(36) 90 Comparison unit

(37) 91 Control data

(38) 92 Frequency components

(39) 93 Frequency amplitude values

(40) 100 Control unit

(41) 100a Controllable delivery pump

(42) 100b Electrically-controllable valve

(43) 100c Electrically-controllable valve

(44) 101 Warning signal

(45) 102 Volume flows

(46) 110 Surface to be coated