Classifications

• • E—FIXED CONSTRUCTIONS
  • E21—EARTH OR ROCK DRILLING; MINING
  • E21C—MINING OR QUARRYING
  • E21C35/00—Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00
  • E21C35/22—Equipment for preventing the formation of, or for removal of, dust

Definitions

• the invention relates to a method for detecting clogging of spraying devices on propulsion or mining machines and to an apparatus for performing this method.
• this reference also refers to security problems which consist in the fact that the machine could still be put into operation, bypassing such simple control measures, and thus an incorrect operation takes place. Such incorrect operation could not last, if the permissible operation of the machine is exclusively dependent on the fact that the water supply is turned on. Namely, such an arrangement could allow operation even if one or more water nozzles are clogged or if one or more valves associated with the water nozzles remain closed because only the pressure is felt for control and even if the flow would be sensed instead of the pressure , a pipe break could lead to failure of the arrangement.
• the invention now aims to provide a method of the type mentioned, in which an entire nozzle beam can be monitored effectively and incorrect operation can be avoided.
• the invention aims at avoiding malfunctions or shutdowns of the machine if the water pressure supply is not carried out with constant pressure.
• Monitoring systems where only one flow controller is manually set to a critical one Flow rate is set, which indicates the clogging of a nozzle, are highly error prone with fluctuating water pressure and lead to an uncontrolled control behavior, which in turn has relatively complex maintenance and adjustment work to avoid unintentional machine shutdown during operation.
• a monitoring method and a monitoring system for a monitoring device e.g. a jetting beam for a cutting tool or a heap on the loading table created, which automatically adjust to the actual on-site conditions and ensure greater security for detecting the failure of a single nozzle.
• the method mentioned in the introduction is characterized in that the pressure and the flow rate of the medium to be supplied to the spraying device are measured, that the measured values are fed to an evaluation circuit and with the desired characteristic curve measured for the spraying device for the dependence of their flow rates on the operating pressure of a error-free spraying device are compared and that deviations from the nominal characteristic of a fault-free spraying device are displayed and / or used as control signals for driving the tunneling and / or mining machine.
• the procedure according to the invention is advantageously such that the permissible deviations from the desired characteristic are stored as a characteristic field in the evaluation circuit, the characteristic field preferably being limited by characteristic curves which corresponds to a deviation of the measured values with less than one defective nozzle.
• a permissible operation results when a predetermined threshold is not exceeded, wherein a particularly high degree of accuracy can be achieved when in fact the characteristics of the individual nozzles are known, such characteristics usually to the factory specifications of the nozzles to count.
• the method is therefore advantageously carried out in such a way that the characteristic curves for determining the characteristic fields are determined as pressure-dependent flow rate characteristic curves for individual nozzles and calculated for the actual number of nozzles of the conditioning device, preferably the threshold value for the shutdown of a drive is set when a characteristic curve is reached, which corresponds to a deviation of the characteristic of the jetting device to the characteristic value of + 0.5 nozzles.
• the shutdown is thus carried out with certainty, if a nozzle fails, so that a high degree of operational reliability with significantly reduced possibilities of unintentional influence on the operational shutdown of the cutting motor is made possible.
• a supply pressure in the case of the method according to the invention, too low a supply pressure can not ensure a sufficient minimum pressure for the flammability safety with methane outgassing and therefore the relevant safety regulations are not met. It can thus be selected as one of the limits, a corresponding lower limit for the supply pressure, with a rapid decrease in the supply pressure, for example, in the case of a hose break or closed supply line can be observed. Further cases of damage to be recognized relate to the fact that jets can be lost from the beam due to mechanical vibrations and, for example, a hose break after the flow sensor can also occur. A leakage in the pressure line after the flow sensor as well as heavily washed nozzles with no longer correct spray pattern have the consequence that the nozzle set must be replaced.
• the device according to the invention for carrying out this method is essentially characterized in that a pressure sensor and a flow rate sensor are provided for the medium to be supplied to the spraying device whose measured values are passed via signal lines to an evaluation circuit, that the evaluation circuit a memory for nominal characteristics of the pressure-dependent curve Contains flow rates of error-free spraying device and provides characteristic fields for the allowable deviation from the desired characteristic and that the evaluation circuit is connected to a display device and / or a control member of the drive of the tunneling and mining machine.
• the device according to the invention and the method according to the invention have the advantage that manual adjustment work can be dispensed with and machine shutdowns, which are based solely on pressure fluctuations of the supply line and on influences which trigger such pressure drops, are largely avoided. It is also advantageous that the BedüsungsSystem can be operated at different pressures and in this way the water consumption and the dust deposition can be influenced without this leading to a malfunction of the device. The number of Overall, electronic surveillance elements can be significantly reduced and the risk of the monitoring system being manipulated by the operating personnel can be minimized.
• FIG. 1 shows a schematic view of the circuit arrangement according to the invention for the spraying
• FIG. 2 shows a characteristic nozzle characteristic as used according to the invention
• FIG. 3 shows a diagrammatic representation of the switching logic.
• Fig.l is 1 schematically a nozzle for spraying a cutting drum, wherein the individual nozzles are designated 2.
• the pressure in the supply line of such nozzles is detected via the control line 3 and the pressure sensor 4.
• the medium is supplied to the nozzle blocks 1 and the nozzles 2 via a pressure reducing valve 5 and the line 6, in which a flow rate sensor 7 is turned on.
• the medium is now not only supplied via the line 8 to the nozzle sticks 1 but also via the line 9 to the nozzles of the loading table, in order to jet the heap and cool in this way.
• the motors to be controlled and, in particular, the cutting motor are schematically indicated by 10, the two loading motors being designated by 11.
• the characteristic field that is correct for the determination of the operating parameter is represented as a nozzle characteristic in FIG.
• a graph showing a change in the flow rate per unit time from the input pressure for the entirety of the respective nozzles can be seen at 12.
• This characteristic curve 12 thus corresponds to the nominal value of the entire nozzle. If a nozzle is added or removed, the corresponding characteristic curve shifts upwards or downwards, the characteristic curve 13 corresponding to the ratios for n + 1 nozzles and the characteristic curve 14 to the ratios for n-1 nozzles. Between each of these two limit values, a fictitious characteristic curve 15 or 16 is computationally or graphically determined in the center, which corresponds in each case to the deviation by half a nozzle.
• the field delimited by the characteristic curves 15 and 16 can be designated as a permissible nozzle characteristic field and as long as the measured values are in the stated range, a correct function can be assumed. At the same time, however, a lower limit value must also be defined, which is determined by the coordinates of point 17 in the representation according to FIG. This point corresponds to the minimum flow rate and the minimum pressure for safe operation, which also results in shutting down of the engine (s) if these values are not reached.
• the permissible characteristic field is thus defined by the hatched area 18.
• the signals of the sensor inputs are referred to as P sensor and Q SensOr and serve on the one hand to control the minimum pressure or the minimum flow rate in the unit time and on the other hand, the calculation of the respective setpoint, which takes into account the pressure dependence of the flow rate.
• the aforementioned control of the minimum pressure and the minimum flow rate leads to a corresponding query of the characteristic curves. If and the pressure value P sensor ⁇ the P min , then the machine may continue to operate and the spray is ok. If the sensor value for the flow in the unit of time falls short of the minimum pressure and if the minimum pressure is undershot, a shutdown is carried out and a corresponding error message is issued.

Landscapes

• Engineering & Computer Science (AREA)
• Mining & Mineral Resources (AREA)
• Mechanical Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Geology (AREA)
• Measuring Volume Flow (AREA)
• Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
• Spray Control Apparatus (AREA)
• Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)

Applications Claiming Priority (2)

Publications (1)

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• 2006
  • 2006-12-13 AT AT20582006A patent/AT505031B1/de not_active IP Right Cessation
• 2007
  • 2007-11-30 WO PCT/AT2007/000541 patent/WO2008070884A1/de active Application Filing
  • 2007-11-30 CN CN2007800462390A patent/CN101573508B/zh not_active Expired - Fee Related
  • 2007-11-30 AU AU2007332121A patent/AU2007332121B2/en not_active Ceased
  • 2007-11-30 EP EP07845272A patent/EP2100005A1/de not_active Withdrawn
• 2009
  • 2009-06-08 ZA ZA200903995A patent/ZA200903995B/xx unknown

Non-Patent Citations (1)

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