The research system for vibration analysis in domestic installation pipes

A measurement and data processing system was developed for investigation of processes that influence sound propagation in pipes, which are commonly used in residence building industry. An impact-type excitation was mainly used for a controlled wide-band frequency mechanical vibrations excitation. Pipe surface vibrations were measured by means of accelerometers and microphones. Scanning device was used for positioning transducers over a tested pipe. The wave propagation and vibration analysis in pipeline segments of several types of pipes (plastic and metallic) was carried out. Because of various pipes working conditions, empty and filled pipes were tested as well. The experimental data indicates that both in metal and plastic pipes vibrations up to several kilohertz may propagate with low attenuation facto

Application of free vibration technique for evaluation of vibro-isolation properties of pipe fixing elements

One approach for reducing noises in pipeline transport systems is selection of appropriate fasteners. Therefore, it is important to know vibro-acoustic characteristics of the fastening elements. This paper proposes a measurement system for determination of dynamic properties of pipe fastening elements and describes performed experiments that demonstrate characteristics dependence on clamping force, construction of the holder and its vibration mode

The research system for vibration analysis in domestic installation pipes

A measurement and data processing system was developed for investigation of processes that influence sound propagation in pipes, which are commonly used in residence building industry. An impact-type excitation was mainly used for a controlled wide-band frequency mechanical vibrations excitation. Pipe surface vibrations were measured by means of accelerometers and microphones. Scanning device was used for positioning transducers over a tested pipe. The wave propagation and vibration analysis in pipeline segments of several types of pipes (plastic and metallic) was carried out. Because of various pipes working conditions, empty and filled pipes were tested as well. The experimental data indicates that both in metal and plastic pipes vibrations up to several kilohertz may propagate with low attenuation facto

The research system for vibration analysis in domestic installation pipes

A measurement and data processing system was developed for investigation of processes that influence sound propagation in pipes, which are commonly used in residence building industry. An impact-type excitation was mainly used for a controlled wide-band frequency mechanical vibrations excitation. Pipe surface vibrations were measured by means of accelerometers and microphones. Scanning device was used for positioning transducers over a tested pipe. The wave propagation and vibration analysis in pipeline segments of several types of pipes (plastic and metallic) was carried out. Because of various pipes working conditions, empty and filled pipes were tested as well. The experimental data indicates that both in metal and plastic pipes vibrations up to several kilohertz may propagate with low attenuation facto

The research system for vibration analysis in domestic installation pipes

A measurement and data processing system was developed for investigation of processes that influence sound propagation in pipes, which are commonly used in residence building industry. An impact-type excitation was mainly used for a controlled wide-band frequency mechanical vibrations excitation. Pipe surface vibrations were measured by means of accelerometers and microphones. Scanning device was used for positioning transducers over a tested pipe. The wave propagation and vibration analysis in pipeline segments of several types of pipes (plastic and metallic) was carried out. Because of various pipes working conditions, empty and filled pipes were tested as well. The experimental data indicates that both in metal and plastic pipes vibrations up to several kilohertz may propagate with low attenuation facto

Measurements and Processing of Signals used in a Cab Signaling System

Automatic cab signaling system used in Lithuanian Railways is uninterruptible signaling system used to transmit the information about an allowable train speed to a cab driver. The performance of this system can be disturbed by various sources of disturbances. One of the main sources is a magnetization of rails. So far there were no other methods to evaluate disturbances that can cause signaling system errors than going by train and monitoring traffic-light signals in a cab. Therefore a system to record signaling system signals was created and a method to process the signals was proposed. The method can be used to make a signal processing and decoding of the previously decoded signals. Furthermore, the proposed algorithm uses slightly different method of signal processing and is potentially more immune to disturbances caused by the rail magnetization. The proposed algorithm was used to process the real signaling system signals. The signals were recorded on a route by going on an electric train. The main results of processing and potential places of disturbances have been shown. The advantage of the proposed algorithm over the currently used one need to be investigated in further research

Geležinkelio bėgių įmagnetinimo trukdžių lokomotyvo signalizacijai tyrimas.

A cab signaling system is used to transfer traffic-light signals to a cab. The signaling signals are magnetic field signals measured by a pick-up coil of a cab. A reception of informative signals is often disturbed by permanent magnetization of rails that occur due to different factors. In this article influence of such disturbing signals is described and their influence to signal reception system is analyzed. Different effects of disturbances to the detection of signaling signals are analyzed in subject to signaling signal frequency, cab speed and other factors

Application of free vibration technique for evaluation of vibro-isolation properties of pipe fixing elements /

One approach for reducing noises in pipeline transport systems is selection of appropriate fasteners. Therefore, it is important to know vibro-acoustic characteristics of the fastening elements. This paper proposes a measurement system for determination of dynamic properties of pipe fastening elements and describes performed experiments that demonstrate characteristics dependence on clamping force, construction of the holder and its vibration modes