Alisa Kuleshova
Faculty: Computer Informational Technology and Automatics
Speciality: Scientific, analytical, environmental devices and systems
Theme of master's work:
Justification and development structure of the acoustic analyzer of main ventillators of shaft
Scientific adviser: Viktor Senko
Materials on the theme of master's work:
Abstract on the theme of master's work: "Justification for the structure of the acoustic analyzer of main ventilators of shaft"
Mechanical ventilator setting creates a pressure difference at the inlet of the ventilation network and leaving it [1].
Modern mining enterprise must have forced ventilation. Termination of ventilation stops the whole technological process of the mine. Need to take people to the surface. Safety and lives of people working in the mine depends of trouble-free operation of ventilation system.
The use of continuous monitoring of the state of the fan will increase the reliability and durability of fans through the timely detection of defects and prevent the destruction of sites of machines.
The purpose of my master's work is to develop a structure of device, which detects defects in the mine fans contactless way without stopping of the mining equipment (using the acoustic method of diagnosis). The proposed method of diagnosis is to analyze the acoustic noise emitted by the fan setting to get information about the presence or absence of breakdowns.
This method has not been used in industry. I plan to develop diagnostic algorithms and the actual structure of the device, based on an analysis of the acoustic oscillations.
As a result, research is planned to collect enough data for a theoretical construction of the acoustic analyzer. The result of the work will be the mathematical description of the defects in the fan, as well as technical implementation unit at the level of detailed structural scheme.
For the construction of the described device I can use data of vibration diagnostics of main fans of mine. The vibrational velocity of the surface that vibrates and the sound pressure level associated correlation dependence.
To construct a system diagnostic equipment needed to go through 5 stages:
Modern mining enterprise must have forced ventilation. Termination of ventilation stops the whole technological process of the mine. Need to take people to the surface. Safety and lives of people working in the mine depends of trouble-free operation of ventilation system.
The use of continuous monitoring of the state of the fan will increase the reliability and durability of fans through the timely detection of defects and prevent the destruction of sites of machines.
The purpose of my master's work is to develop a structure of device, which detects defects in the mine fans contactless way without stopping of the mining equipment (using the acoustic method of diagnosis). The proposed method of diagnosis is to analyze the acoustic noise emitted by the fan setting to get information about the presence or absence of breakdowns.
This method has not been used in industry. I plan to develop diagnostic algorithms and the actual structure of the device, based on an analysis of the acoustic oscillations.
As a result, research is planned to collect enough data for a theoretical construction of the acoustic analyzer. The result of the work will be the mathematical description of the defects in the fan, as well as technical implementation unit at the level of detailed structural scheme.
For the construction of the described device I can use data of vibration diagnostics of main fans of mine. The vibrational velocity of the surface that vibrates and the sound pressure level associated correlation dependence.
To construct a system diagnostic equipment needed to go through 5 stages:
- The scaling defects.
The basic fault fan impellers: a loose fit and unbalance of the impeller; buildup of dust or moisture shovels and ice formation, the appearance of fatigue cracks, the imbalance of the rotor. Typically, the service life of fans of mine is distributed life bearing. The most probable faults of rolling bearings include workmanship and installation, cracks and spalling, the discrepancy of the inner ring bearing and shaft journal, the change in the working gap by planting tightness; bias [2]. - Defining a maximum possible measured state parameters
The measured parameters in the developed device are:
- Sound pressure level, dB;
- Ambient temperature, ° C;
- Rotor speed, 1/s.
- Determination of standard and threshold values of monitored parameters
According to the guidance on conducting expert researches of the main ventilation fan systems frequency defects manifest on depend on the rotor speed and the natural frequencies of the fan parts [3]. - The choice of methods and technical means of measurement and analysis of diagnostic signals
As a primary transmitter of sound pressure use condenser microphones (with sound pressure levels up to 140 dB). For expansion in the range of the acoustic signal is used by the sound spectrum with a frequency range from fractions of Hz to 10,000 Hz. The microprocessor decides on the presence of defects in the fan and provides this information to the operator. - Establishment of diagnostic model
Establishment of diagnostic model of the mine fan is one of the sections of master's work. Analyzing all of the above, we can make the following conclusions: - At this time developed a large database that allows you to build a device for nondestructive testing of main fans of mine by noisediagnostic method. - There is still a lot of work in the study of acoustic noise fan, the impact that non-informative environmental parameters such as temperature or other sound sources, studies of the effect on the spectrum of sound pressure paths of sound.
REFERENCES
1. Ивановский И.Г. Шахтные вентиляторы: Учеб. пособие.—
Владивосток: Изд-во ДВГТУ, 2003. – 196 с.
2. Капустин К.Н. Исследование и обоснование структуры и параметров микропроцессорного устройства контроля вибрации вентиляторов главного проветривания угольных шахт. [Электронный ресурс]/ Капустин К. Н. – Режим доступа: http://www.masters.donntu.ru/2001/kita/kapustin/ diss/index.htm Дата обращения: 06.04.2011.
3. РД 03-427-01. Методические указания по проведению экспертных обследований вентиляторных установок главного проветривания. – Введ. 2002-04-01. – Госгортехнадзор РФ, 2001- 47с.