Communications and Public Affairs
P.O. Box 6042, Station
Montreal P.Q. H3C 3E4
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Volume 22 Number 10
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December 1992/January 1993
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Super Tie Shows its Mettle in the
Toughest of Our Terrains
By John Timmins
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A profile of Super Tie provided by CP Rail System -
Engineering.
All the Strength of Steel and Oak
After one year of testing, CP Rail System's Super Tie continues to withstand heavy loads on curves and steep
grades in some of the most severe mountain terrain on Heavy Haul territory.
Developed by CP Rail System - Engineering, Super Tie is an enhanced, creosote-treated, premium
hardwood crosstie made of red or white oak. The enhanced features include an end plate that prevents splitting,
a wear barrier plate that prevents tie plate cutting, and an eccentric tie plate used specifically in curves.
Ed Taylor, supervisor track design & development, CP Rail System - Engineering, says he is confident the
new Super Tie will outlast the service life of standard ties under these conditions.
"We can honestly say that we will get from a 12 to 14-year service life to a potential
20 years", Mr. Taylor said. "The hardwood ties we took out of the curves on the Shuswap subdivision
and replaced were only 12 years old, but they had tie plate seats that were worn to a depth of 3.75 cm".
Progressive
Mr. Taylor, who is responsible for the design, development, and testing of Super Tie, says the enhanced
crosstie represents leading edge engineering.
"There can be no doubt that CP Rail System is keeping a progressive outlook on the integrity of the entire
track structure in order to meet the challenges of the 21st century", he said.
The end plates and wear barrier plates for the new crossties were supplied by Burke-Parsons-Bowlby
Corp. of Dubois, Pennsylvania, and Plate-a-Tie Products of Sullivan, Missouri.
Two Super Tie installations have been completed on Heavy Haul territory. By November 1992, 3,000 Super Ties had
been installed in curves on the Shuswap subdivision, just west of Revelstoke, B.C.
The second and most recent installation of 4,000 Super Ties is located between miles 95.5 and 97.8 on the
Mountain subdivision, 40 km east of Revelstoke. Installation took place in mid-September 1992.
On the Mountain subdivision, where the word "severe" falls short of accurately describing the
mountainous terrain, Super Tie must withstand an average of 63 million tonnes of traffic a year on
11-degree curves with descending grades of up to 2.5 percent.
"If the Super Tie is proven in this area, it will certainly cope with any condition throughout CP Rail
System", Mr. Taylor said.
Super Fair Rail Anchor
Mr. Taylor and his colleague, Al Wilson, engineer, maintenance of way, Heavy Haul, are carefully studying the
behaviour of the tie plate fastenings that consist of standard cut spikes on the rail seat of each tie plate
and two Vossloh screwspikes with spring washers for the hold-down. These screwspikes rigidly fasten
the tie plate to the top of the crosstie to prevent any lateral movement of the tie plate. ( see diagram above)
Also under close study on the Mountain subdivision installation is the Super Fair Rail Anchor, the product of
a collaboration between CP Rail System - Engineering and Portec Ltd. of Montreal.
A Tremendous Product
The new rail anchor has almost twice the contact area on the side of the tie as does the standard rail anchor.
It can resist longitudinal movement of the rail in excess of 4,600 kg., compared to the standard Portec
Improved Fair Rail Anchor that can maintain resistance up to 3,400 kg.
"It's a tremendous product", Mr. Taylor said. "One of its main features is that it can be applied
and removed up to 60 times with absolutely no loss of holding power".
The use of the Super Fair Rail Anchor and screwspikes was not part of the first installation on the Shuswap
subdivision.
"On the Shuswap we wanted to see the effects of using five standard cut spikes for each tieplate which
permit vertical movement of the plates. With the cut spikes, we are experiencing some transverse movement of
the tie plates during the passage of trains", Mr. Taylor said.
A review of both installations is planned for the spring.
Hardwood Crossties Have No Rival
When it Comes to Quality
Ed Taylor, left, supervisor, track design & development, CP Rail System
- Engineering and Ed Palasz, roadmaster ( East ), Revelstoke Division, Heavy Haul, meet prior to the
installation of 4,000 Super Ties on the Mountain subdivision to discuss the advantages of the Vossloh
screwspike and the Super Tie assembly ( left side of photo ).
Ed Taylor is sold on premium hardwood crossties.
CP Rail System's supervisor of track design & development says in-track testing of the Super
Tie in British Columbia is proving that premium hardwood crossties are preferable in severe mountain terrain to
any type of crosstie currently in use on Heavy Haul.
Impressive Behaviour
Mr. Taylor's preference stems from laboratory testing and the impressive in-track behavior of red
and white oak ties under continuous heavy loads on the Shuswap and Mountain subdivisions. "The oak is so
hard that it's promoting wear on the mild carbon steel plates", he said. "We did not anticipate this.
As a result, all new tie plates are made of medium-carbon steel".
He said the real strength of oak is evident where it resists track gauge widening - the distance between the
railheads.
Every Super Tie crosstie is a full-square cross section with corners and no wane or lack of wood
along the edges. These premium ties are cut from oak trees in the Appalachian forests of the U.S.
Mr. Taylor, with assistance from Phil Bird, general tie and lumber agent for CP Rail System, developed
specifications using only premium oak that exceeded current crosstie specifications for wood quality and
dimension. This meant that no fewer than 10,000 crossties were looked at to select 3,000 crossties for the
Shuswap subdivision installation. The same kind of selection ratio was used for the Mountain subdivision
installation.
He also insisted on placing the sapwood ( the side of the crosstie cut closest to the outside of the tree )
face down into the ballast, and installing wear barrier plates on top of the stronger and denser heartwood or
heart side of the crosstie.
Better Support
"It is generally accepted that the sapwood face of the crosstie should lie face up. This is completely
wrong", he said. "The sapwood side has a more porous grain, which the creosote can penetrate more
deeply".
"By having the heart side facing up, the denser wood structure will provide better support for the tie
plate and prolong the crushing of the wood, which is the primary reason for crosstie
replacement".
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This CP Rail News article is copyright
1992 by the Canadian Pacific Railway and is reprinted here with
their permission. All photographs, logos, and trademarks are the property of the Canadian Pacific Railway
Company.
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