dr martin murray - kcpm consulting - managing the track asset through wheel maintenance
TRANSCRIPT
Managing track through wheel
maintenance
Dr Martin Murray
20 May 2014
Brisbane
Who am I? • Director of KCPM Consulting (track consulting business)
• BE (Civil) 1973, PhD (Melb) 1978
• 25 years of R&D projects and consulting work for railway
industry
• Published >60 international papers on rail track
• Created railway infrastructure MEng @ QUT
• University academic for 35 years
• Grandfather, pastor, grey & bald, & >50!
• Presentation drawn from CORE2012 conference paper..
What’s the problem?
But aren’t track forces well understood?
Accepted wisdom for safe operation of trains & track and to
ensure long life in train & track components:
• Maximum impact force for wagons: ~230kN
• Maximum impact force for locos: ~300kN
• Where these forces are exceeded due to wheel-tread defects,
the wheels should be removed and machined..
A rich source of data from real trains & track
Typical maximum
permitted impact
force Weibull
distribution
What are the real forces? - 1
What are the real forces? - 2
What’s a Weibull distribution?
I = magnitude of impact force (kN)
f = frequency of occurrence of force
(the rest are constants defining the shape of the curve)…
Typical maximum
permitted impact
force
What are the real forces? - 3
1.5% of all axles
> 1 million axles /annum each site
=1 axle/year
What are the real forces? - 4 Four WID sites
Three Aust. states
Three track owners
Coal & ore trains
All >100MGT/a
60-68kg/m rail
Heavy conc sleepers
≥ 250mm ballast
25-35TAL
70-80km/h
Many Gb of data
2005 to 2011
What are the real forces? - 5
What are the real forces? - 5
What are the real forces? - 5
What are the real forces? - 5
What are the real forces? - 6
A1
A2 B
What are the real forces? - 7
What are the real forces? - 7
What’s going on here? • Large impact forces at WID sites are from
defected wheels, eg wheel flats
• So, smaller impact forces must mean less
severe wheel defects in the fleet (esp for large
axle loads)
• Less severe fleet defects are related to
operator issues:
• Harder steel chosen for wheel treads, and/or
• “Gentler” driver behaviour through training &
supervision, & better braking systems, and/or
• Better policy & practice with defect detection,
removal, rectification…
www.sodahead.com
www.trainboard.com
And the consequences are? The policies and practices of the operator
can dramatically affect maximum track
forces, which means for the track owner:
• better operator policies & practices can
mean cheaper track;
• with this sort of WID data analysis, the track
owner can:
• reward a diligent operator and/or penalise
lower quality operator;
• make informed decisions about future
growth in traffic volumes, speeds and axle
loadings…
www.kenyan-post.com
Managing the track asset through
wheel maintenance
Dr Martin Murray
20 May 2014
Brisbane
Thank you