Track
Onboard monitoring a A
An onboard track monitoring system developed by Ensco, United States, is helping to eliminate the use of track geometry recording vehicles and on-track inspectors, potentially saving time and money. Jeff Stevens, deputy division manager at Ensco, profiles the system.
S efficiency demands on railways increase, prioritising track maintenance before poor conditions cause vehicle damage or derailments is becoming more of a challenge. As a result, the industry is turning to new technologies to optimise track maintenance planning, including use of vehicles equipped with sensors that quantify conditions and automatically report to Maintenance of Way (MoW) managers the location and severity of problems.
Ensco’s Autonomous Vehicle/Track Interaction (V/TI) Monitor, which provides unattended condition-based monitoring of the interactions that take place between rail vehicles and track, is one such technology.
By equipping locomotives, passenger coaches or wagons with compact sensors, GPS and wireless communication devices, the V/TI Monitor applies a “train path free” approach that does not require use of dedicated measurement vehicles with specialised personnel onboard. This
approach facilitates cost-effective and frequent condition-based monitoring of track infrastructure with 24x7 real-time automated reporting of safety critical conditions, as well as office-based automated analysis and reporting tools for longer range degradation monitoring and maintenance planning. The basic components of the V/TI Monitor include a central CPU, mobile phone/GPS antenna, and sensors mounted in various positions on the vehicle. Each sensor is measured continuously, and when a value exceeds a predetermined threshold, a notification is created that includes the time, GPS coordinates, sensor reading, and time of the continuous sampled sensor data.
The V/TI Monitor platform is configurable and expandable for various conditions. However, the track maintenance user-base typically focuses on four primary areas of condition-
based monitoring: lateral track irregularities: typically attributed to track alignment irregularities that cause lateral vehicle
excitation. Bridges are often the site of these irregularities due to settling and vehicles often experience lateral
acceleration values as they pass long wavelength vertical track irregularities: typically attributed to repeated, long wavelength track top irregularities that excite the vehicle with pitch and bounce motions and result in vertical acceleration values. Common causes include poor drainage or sleeper conditions occurring in areas equal to or
greater than 10m, and short wavelength vertical track irregularities: attributed to track top irregularities situated three metres or less apart with actual displacement measurements reported in millimetres for each rail. Common detections include poor support conditions (pumping) joints or failed sleepers. Many of these conditions are traditionally detected by a combination of track geometry recording vehicles and human inspections. And while it could potentially replace these methods, V/TI also detects conditions not evaluated by these techniques, such as
Onboard monitoring is making it easier to identify track defects including, from left to right, wheel/rail impact, long wavelength vertical 44
IRJ May 2013
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60