Embed Size (px)
DESCRIPTION
David Cooper delivered the presentation at 2014 RISSB Wheel Rail Interface Forum. The RISSB Wheel Rail Interface Forum reviewed the fundamentals of what happens between wheel and rail before focusing on the practicalities of monitoring, interventions, maintenance, management and the critical importance of the interdisciplinary cooperation. For more information about the event, please visit: http://www.informa.com.au/wheelrailinterface14
Citation preview
Rail Studs
Current Understanding of
Occurrences in the Sydney Rail
Network
David Cooper WRI,Brisbane,
21st May 2014
Rail Studs
Current Understanding of Occurrences in the
Sydney Rail Network
Output from a series of site visits undertaken by
Malcolm Kerr Sydney Trains
Dr Stuart Grassie Rail Measurement Ltd UK
Andrew Wilson Sydney Trains
David Cooper Asset Standards Authority
This work is currently ongoing and the
presentation content is not absolutely
conclusive
Rail Studs - Sydney Rail Network
Similar Defect Types:
• Squat (Charles Frederick,BRR)
First
Derailment
, Cropredy
1974
Rail Studs - Sydney Rail Network
Rolling Contact Fatigue Early 1970’s
First Derailment 1989, Euston Station
Rail Studs - Sydney Rail Network
• First seen on high speed
passenger lines
• Reached Hunter Valley in
mid 1990’s
• Unheard of in RailCorp
territory before 2000
• Probably existed, but not
recognized and too few
• 2,862 found in 262km in
2007
• Now growing rapidly. 16km
rail testing affected Sept
2012.
Rail Studs NSW WEL Sub-Surface Propagation
Initiation
• Relatively benign
• Horizontal shelling
Rail Studs - Sydney Rail Network
Rail Studs - Sydney Rail Network
Rail Studs NSW
Multiple Studs
Rail Studs - Sydney Rail Network
Rail Studs - Sydney Rail Network
White Etching Layer (WEL)
Rail Studs - Sydney Rail Network
• Early detection
Eddy Current
Rail Studs - Sydney Rail Network
• High rail of curves over
600m radius
• 1 or both rails on straight
track
• Turnouts
• All types of sleepers and
rails.
• Less prevalent in
standard carbon.
• Traction influence
• Prevalent on rail welds.
• No clear relationship with
grades, stations or signal
locations.
• Lines with passenger only,
freight only and mixed traffic.
• Rails that have and have not
been ground.
• Do not occur in tunnels,
apart from at wet locations.
• Management – Early detection
• Identify potential locations
• Visual identification late stage in propagation
– Preventative Grinding programme • Rail head profile
– Minimise contact stresses
– Rail Selection • Rail renewal if stud significant depth >3 mm
• SC rail - magic wear rate
• HH rail – facilitates propagation
– Traction Power
• AC traction coefficients
• Co Co configuration
• Micro wheel slip
Rail Studs - Sydney Rail Network
Rail Studs - Sydney Rail Network
15
Squat or Stud?
1980’s
