Method and apparatus for detecting the condition of the flow of liquid metal in and from a teeming vessel

• US 5,633,462 A
• Filed: 07/19/1994
• Issued: 05/27/1997
• Est. Priority Date: 07/19/1994
• Status: Expired due to Term

• Current Assignee: Vesuvius Crucible Company (Vesuvius Plc)
• Original Assignee: APA Systems Ltd.
• Inventors: Heaslip, Lawrence J., Dorricott, James D.
• Primary Examiner(s): Oda, Christine K.
• Application Number:
  US08/277,409
• Time in Patent Office: 1,043 Days
• Field of Search: 73/64.53, 73/53.01, 73/1 DV, 73/649, 73/658, 73/659, 164/155.1, 164/453, 164/457, 164/150.1, 164/4.1, 364/509, 364/508, 364/571.04
• US Class Current: 73/649
• CPC Class Codes: G01F 1/666 by detecting noise and sounds generated by the flowing fluid
• CPC Class Codes: G01N 2291/014 Resonance or resonant frequency
• CPC Class Codes: G01N 2291/0252 Melting, molten solids
• CPC Class Codes: G01N 2291/02836 Flow rate, liquid level
• CPC Class Codes: G01N 29/14 using acoustic emission techniques echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00
• CPC Class Codes: G01N 29/449 Statistical methods not provided for in G01N29/4409, e.g. averaging, smoothing and interpolation

Abstract

An apparatus for detecting the condition of the flow of liquid metal in or from a teeming vessel includes a sensor for detecting vibration caused by a flow of liquid metal in or from the teeming vessel and for outputting a sensor signal corresponding to an amount of vibration detected by the sensor. A signal processor receives the sensor signal and compares the sensor signal to a reference signal and outputs a comparison signal. A logic unit receives the comparison signal and outputs a status signal indicative of the condition of the flow of the liquid metal in or from the teeming vessel.

Claims

1. An apparatus for detecting the condition of the flow of liquid metal in or from a teeming vessel comprising:

a sensor for measuring a desired flow condition of liquid metal flowing from a teeming vessel to output a reference signal corresponding to the desired flow condition, and for monitoring the status of the flow condition of the liquid metal flowing from the teeming vessel to output a sensor signal corresponding to the status of the flow condition;

a signal processor for comparing the sensor signal to the reference signal and outputting a comparison signal; and

a logic unit for receiving the comparison signal and for outputting a status signal indicative of the condition of the flow of the liquid metal in or from the teeming vessel.

2. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the sensor signal is received by a differential charge amplifier for eliminating low frequency noise before the sensor signal is received by the signal processor.

3. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the teeming vessel includes a valve to regulate the flow of liquid metal from the teeming vessel.

4. The apparatus for detecting the condition of the flow of liquid metal of claim 3, wherein the valve is in fluid communication with a passageway for flowing the liquid metal from the teeming vessel to a receiving vessel.

5. The apparatus for detecting the condition of the flow of liquid metal of claim 4, wherein the passageway is in operative engagement with a lifting device constructed and arranged to move the passageway into and out of fluid communication with the receiving vessel.

6. The apparatus for detecting the condition of the flow of liquid metal of claim 5, including a control panel for receiving the status signal.

7. The apparatus for detecting the condition of the flow of liquid metal of claim 6, wherein the control panel includes means for closing the valve to stop the flow of liquid metal out of the teeming vessel if the status signal indicates an undesired flow condition of the liquid metal in or from the teeming vessel.

8. The apparatus for detecting the condition of the flow of liquid metal of claim 6, wherein the control panel includes means for displaying the condition of the flow of liquid metal in or from the teeming vessel in response to the status signal.

9. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the sensor is a microphone.

10. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the sensor is an accelerometer.

11. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the signal processor divides the sensor signal into frequency bands.

12. The apparatus for detecting the condition of the flow of liquid metal of claim 11, wherein the signal processor outputs the frequency bands as a data spectrum.

13. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the signal processor divides the sensor signal into a frequency range of about 0.1 Hz to 20 kHz.

14. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the logic unit is a central processing unit.

15. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the status signal is indicative of an undesirable flow condition of the liquid metal in or from the teeming vessel.

16. The apparatus for detecting the condition of the flow of liquid metal of claim 15, wherein the undesirable flow condition includes one of vortexing, flow rate irregularity, surface collapse, flow plugging or gaseous aspiration.

17. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the status signal is indicative of a desirable flow condition of the liquid metal in or from the teeming vessel.

18. The apparatus for detecting the condition of the flow of liquid metal of claim 15, wherein the undesirable flow condition is slag entrainment.

19. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the signal processor compares the sensor signal to the reference signal in real time.

20. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the signal processor divides the sensor signal into a first set of frequency bands and outputs the first set of frequency bands as a calibration spectrum, divides the reference signal into a second set of frequency bands and outputs the second set of frequency bands as a data spectrum, and compares the data spectrum to the calibration spectrum in real time.

21. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the sensor signal is outputted after the reference signal is outputted.

27. The apparatus for detecting the condition of the flow of liquid metal of claim 1, wherein the signal processor divides the reference signal into frequency bands.

28. The apparatus for detecting the condition of the flow of liquid metal of claim 27, wherein the signal processor outputs the frequency bands as a calibration spectrum.

22. A method for detecting a condition of a liquid metal flow in or from a teeming vessel, the method comprising the steps of:

flowing liquid metal from a teeming vessel;

measuring a desired flow condition of the liquid metal flowing from the teeming vessel;

converting the desired flow condition to a reference signal;

monitoring the status of the flow condition of the liquid metal flowing from the teeming vessel;

converting the status of the flow condition to a sensor signal;

comparing the sensor signal to the reference signal to output a comparison signal; and

outputting a status signal in response to the comparison signal, the status signal being indicative of a condition of the flow of the liquid metal in or from the teeming vessel.

23. The method for detecting the condition of the flow of liquid metal of claim 22, wherein the sensor signal is amplified for eliminating low frequency noise before the sensor signal is compared to the reference signal.

24. A method for detecting a condition of a liquid metal flow in or from a teeming vessel, the method comprising the steps of:

flowing liquid metal from a teeming vessel;

measuring a desired flow condition of the liquid metal flowing from the teeming vessel;

monitoring the status of the flow condition of the liquid metal flowing from the teeming vessel;

comparing the desired flow condition to the status of the flow condition; and

outputting a status signal indicative of a condition of the flow of the liquid metal in or from the teeming vessel.

25. An apparatus for detecting a condition of the flow of liquid metal in or from a teeming vessel comprising:

means for flowing liquid metal from a teeming vessel;

means for measuring a desired flow condition of the liquid metal flowing from the teeming vessel;

means for converting the desired flow condition to a reference signal;

means for monitoring the status of the flow condition of the liquid metal flowing from the teeming vessel;

means for converting the status of the flow condition to a sensor signal;

means for comparing the sensor signal to the reference signal to output a comparison signal; and

means for outputting a status signal in response to the comparison signal, the status signal being indicative of a condition of the flow of the liquid metal in or from the teeming vessel.

26. An apparatus for detecting a condition of the flow of liquid metal in or from a teeming vessel comprising:

a sensor for measuring a desired flow condition of liquid metal flowing from the teeming vessel, and for monitoring the status of the flow condition of the liquid metal flowing from the teeming vessel;

a signal processor for converting the desired flow condition to a reference signal, for converting the status of the flow condition to a sensor signal, and for comparing the sensor signal to the reference signal to output a comparison signal; and

a logic unit for outputting a status signal in response to the comparison signal to indicate a condition of the flow of the liquid metal in or from the teeming vessel.