Wayside Condition Monitoring Technologies for Railway Systems

Projekt:

JVTC

Sammanfattning:
The railway is an important mode of transport, due to its environmental friendliness, high
safety level, and low energy consumption, among other reasons. Railways provide a
sustainable means of transporting a large amount of freight and passengers, in a cost-effective
and comfortable way. The railway system has a large number of stakeholders and a small
improvement in the system will give many advantages, including financial savings and an
increase in the quality of service. The Swedish railway network is old and there has been
almost no expansion of the network during the past few decades. There is currently a demand
for more track capacity and there are no more tracks availably at the network; therefore, the
existing network is expected to deliver more capacity.
The railway operators are the largest cause of train delays and wheel failures are one major
contributor of the delays caused by operators. The infrastructure manager is the second largest
owner of train delays, and a large contributor of their train delays is switches and crossings
(S&Cs).
This thesis shows proposals for how condition monitoring technology can be used more
efficiently for both the infrastructure and the rolling stock to increase the reliability of their
critical items by decreasing train delay.
Firstly, the condition of the wheel-rail interface is important, in that a bad wheel influences
the rail and vice versa. The monitoring of rail profiles is already in use, but the monitoring of
wheel profiles is still in the development phase. This thesis shows the performance of a wheel
profile measurement system (WPMS) for an extreme climate, and a case study of
performance measures such as the accuracy and reliability of the system is presented. An
additional topic dealt with is how the information from the WPMS can be combined with that
from the wheel defect detectors to find early indications of wheels with bad behaviour.
Secondly, the S&C is an essential component of a railway system in that it increases the
flexibility by diverting traffic, but S&Cs need adequate support to work properly. A cameramonitoring
method for S&Cs is presented which increases the inspection frequency and
decreases the human activities on the track and the train delay.
In conclusion, this thesis shows that the WPMS investigated works well with a high level of
performance concerning measurement accuracy and reliability in an extreme climate, and that
there is still some potential for improving the system. The combination of the WPMS and
wheel defect detectors shows that wheels with a high flange height have a higher probability
of ending up as wheels suffering from failures. A new maintenance limit for the flange height
can reduce the number of wheel defects on the track. Camera-monitoring of the S&C will
increase the availability and reliability of this item and even reduce the time on the track
required for the maintenance action “check” through fewer inspections and maintenance
actions. These proposed monitoring techniques can improve the railway system reliability by
reducing the consequential train delay times, by decreasing the number of failures of wheels
and S&Cs.

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Författare: Matthias Asplund
Utgivare: Luleå tekniska universitet
Utgivningsdatum: 2014-01-30
Diarienummer: TRV 2011/58769
ISBN: 978-91-7439-846-5
Språk: Engelska
Kontaktperson: Per Olof Larsson Kråik, UHjbs