As one of the most important transportation, the safety of railway is paid much attention to. The quality of wheel should
be checked periodically, especially in high-speed application. Normally, Non Destructive Testing (NDT), such as
ultrasonic inspection method, is applied on wheels to find the defect. A stationary automatic railway wheelset inspection
system by using ultrasonic technique is described in this paper. The phased array ultrasonic technique and wheel defect
inspection method is described in detail. Specially designed line is installed for wheelset transportation. Wheelset lifting
and rotating device is used for wheelset loading, unloading and rotating. A steel frame with complicated mechanical
structure and ultrasonic devices are designed for wheelset defect detecting. System ultrasonic performance, system
working flow, system control networking, data processing and results displaying are also described in the paper. Now,
the system is installed in Chinese EMU maintenance center for disassembled wheelset inspection and the safety of
wheels is well protected.
Pantograph sliding plate is the most important electricity-collecting part in locomotive power supply system. Once the
sliding plates are disabled, they will be severe dangerous for safety. The measurement for pantograph of 27.5KV is
especially difficult. The article uses non-contact and online dynamic detection by utilizing CCD technique to solve the
problem. The system will get all images of sliding plates after triggering by space arrangement of CCD cameras
cooperated with flashlights. The precision of demarcate is guaranteed by special methods. It adopts directional edge
search to get sliding plates, and connect the images of different CCDS. It also makes use of conditional Hough
transformation to locate the wire. The wear on sliding plates will be given after complicated processing. The system is
applicable to the detection for all kinds of pantographs by adding different arithmetic amends. At last the precision can
achieve ±0.5mm . At the same time a database is setup which can give the trend curve of wear, it can predict the limit
time of the sliding plates.
In this paper, the importance of the contact line height and gradient in the electrified railway and the current inspection methods for the contact line height and gradient are analyzed, and then the dynamic detection system for that is deigned, which based on the laser phase ranging principle. The detection system is setting on the top of locomotive and a cooperative target is fixed on the pantograph; the laser system measures the height between the top of locomotive and the working pantograph by the cooperative target when the locomotive runs, and then the gradient of contact line can be calculated in real time when the locomotive's running information is provided. The laser phase ranging system uses the DFT method to calculate the phase difference, which can get the higher resolution than the method of the electronic phase demodulation and reduce the influence of the shift of laser intensity etc. The dynamic detection system works well to detect the contact line gradient, without influencing the normal operation of the locomotive, and the disadvantages of manual detecting and detecting car are avoided.
The railway line profile measurement is necessary for the safety of the train. This article expounds a method of railway line profile measuring using laser ranging and laser scanning technology with high precision and speed. With this method, the obstacle near the track can be found out and the hidden trouble can be removed. In tunnel, the crack and deformation on the tunnel wall can be measured. The parameter of the track and contact wire can be also inspected, such as rail gauge and superelevation, position of contact wire (stagger and height), wire wearing.