Autonomous damage detection system for railway axle journal bearings

Abstract

Since axle journal roller bearings of the bogie of rolling stock are important components for the running of the vehicles, early detection of damage to axle bearings is required. Therefore, we developed an autonomous damage detection system "ADDS" as one of the detection devices. The ADDS uses energy harvesting technology that utilizes the power generation function of the piezoelectric element “PZT”. The ADDS can detect axle bearing damage and transmit obtained data to receiver that will be installed under floor of the vehicle without a power supply and cable connection from the vehicle body. In the ADDS, the anti-vibration rubber for axle springs, which is installed on the axle box is replaced by an autonomous damage detection anti-vibration rubber "ADDAR". The ADDAR contains the PZT as a power generation module “PGM” and a transmitter that transmits the detected data to receiver. The transmitter in the ADDAR can be driven by electric power from the PGM. The rotational test to evaluate the performance of the ADDAR was carried out using an axle journal bearing performance rig. The test results show that the power generation performance of the PGM of the ADDAR installed on the damaged axle bearing is higher than that of the ADDAR installed on the normal axle bearing. It is confirmed that the transmitter in the ADDAR installed on the damaged axle bearing can transmit the obtained data to the receiver. Additionally, the power generation performance of the ADDAR is improved when the PGM is installed directly above the damaged location of the axle bearing. In this case, the ADDAR can secure the power to drive the transmitter even at low rotational speeds.

Keywords

• axle bearing
• autonomous damage detecntion system
• enargy harvesting
• piezoelectric elements
• anti-vibration rubber
• power generation module
• transmitter
• rotation test