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Title Page. The Environmental Impact of Mechanised Maintenance for the Preservation of Railway Track Geometry Kenneth Baker SID: 0410972 HND Civil Engineering 2004/2005

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Title Page.

The Environmental Impact of Mechanised Maintenance for the Preservation of

Railway Track Geometry

Kenneth BakerSID: 0410972

HND Civil Engineering2004/2005

Module Code CTB 1024Module Name Information Management &

TechnologyCoursework Identifier

Sem2

Marker Aidan Garbutt

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Abstract. (exec summary 200 words).

Bakground, research method, main findings, conclusions and recommendations.

This Report is on the environmental impact of On Track Machines for the maintenance of the Track Geometry on the Railway. It was perceived that the older design Tamper Machines would be more environmentally unfriendly than the newer Stoneblowers. Also the Tamping machines replaced gangs of 100 men per machine and although not originally considered had to be evaluated to determine the best way to maintain the track geometry.

Reseach material available was very limited with just one published document and a handful of internet sites. These were mainly from manufacturers, so had to be evaluated carefully as they obviously stated their machines were better.

Main findings,

Conclusions,

Recommendations,

Acknowldgement.

Who helped, interviews, time advice information etc.

Help for the report was mainly from the staff using the machines. These included, Andy Black, Track Quality Supervisor. Peter Cooper, Track Quality Supervisor. Neville Hylton, Plant Co-ordinator. They gave an insight into the machines and their benefits to the railway.

Network Rail Public Relations gave information on the number of reports from members of the Public who had complained about noise and vibration from the Railway.

Territory Plant Engineer, Hugh Allen gave advice and figures on the use of the machines and their ‘consumables’ (Fuel, Stone, Hydraulic Oil).

Contents.

Auto from Header

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Introduction.

Who am I, what do I do. Subject area, focus on particular areas. Reason. Aims and Objectives.

This Report is on the environmental impact of On Track Machines for the maintenance of the Track Geometry on the Railway. I had a preconceived idea that the new Stonbeblowers were more environmentally friendly than the older Tamping Machines. While this is partially true, they all have a great impact on the environment. The tamping machines were introduced in the late 50’s, with the first true tamping machine being produced by Matisa in Chertsy around 1956. These machines were produced to replace the work of 100 men. As a comparison I will look at the environmental impact of all three types of maintenance, Human, Tamper and Stoneblower.

On initial investigation from various sources, it appeared that Stoneblowing was going to be by far the most environmentally friendly. Compared to 100 men, with their transport (normally 6 men to a van working in a gang of 12) and on occasions hand held machinery. The Enviromnntal issues with this type of maintenance would be: Noise pollution, as 100 P-Way men make a lot of noise and the language is not always very clean. In last years Public relations recods 18 cases apposed to just 2 for machine noise.

Aims and Objectives.

Research Methodollogy.

How I’m going to do it. What methods, why.

Results of Research.

Processes, observations, summary of tables.

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Dsicussion of results.

Evaluate, argue, discuss. Implications

Conclusion.

Short, main points.

Recommendations.

Follow up, further research.

References.

Bibliography.

Appendices.

The search for an improved mechanised method of maintaining railway track to the correct level and alignment led to the development of the Stoneblower, a machine that lifts the rail and attached sleepers and pneumatically injects the required amount of 20 mm stone into the void created. This minimises disturbance to the existing well-compacted ballast. By 1999 a fleet of Stoneblowers was fully operational across the UK rail network and achieving target rates of track maintenance. This paper compares the track-quality data recorded before, during and after Stoneblower maintenance and confirms the potential of the Stoneblower. Detailed analysis of the data has given a better understanding of the performance, and has provided guidance for optimising the deployment of the Stoneblowers and the stoneblowing procedures.

The Deformation Behaviour of Bi-Layered Granular Materials...

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  Peter Fair

  Prof. Bill Anderson

  EPSRC CASE Award:Railtrack

The Deformation Behaviour of Bi-Layered Granular Materials in a Railway Environment

Introduction

   

With the passage of traffic railway track ballast degrades and the track loses its line and level and requires maintenance. This has traditionally been carried out by tamping which rearranges the existing ballast under each sleeper. Following many years of plant development Railtrack have recently introduced a fleet of computer controlled Stoneblower machines to the UK rail network. The Stoneblower uses Pneumatic Ballast Injection (PBI) to blow smaller size stone under each sleeper and thus reset the track geometry to the correct level. This results in a two layer granular sleeper foundation system.

The Deformation Behaviour of Bi-Layered Granular Materials...

Tamping

Stoneblowing

What is Design Overlift®?Design Overlift® is a method developed by AEA Technology Rail, which greatly improves the durability of tamping.

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Smooth Lift Iimitations Conventional maintenance tamping applies relatively modest lifts to the track, which create a smooth vertical profile.

Unfortunately, with the passage of traffic, the track rapidly settles back to its original profile. This effect is known as “ballast memory”. Ineffectual tamping is costly because (i) tamping services have to be bought-in frequently and (ii) each tamp contributes significantly to the premature destruction of the ballast.

Why Smooth Lifting failsThe main reason why small lifts cannot create stable residual changes to vertical geometry is because the size of the ballast particles is large relative to the required lifts. Therefore little new stone is introduced under the sleepers during the tamping operation, the existing supporting ballast is merely rearranged. Traffic loading consolidates the disturbed ballast, which takes up its original orientation, thereby revealing the original faults.

Attempts to solve the problemVarious methods have been attempted to overcome this problem. For instance, the application of constant large lifts will result in permanent change to the track profile but the final geometry will not be particularly smooth and the process wastes ballast. Another method, known as “mirror tamping”, requires a measurement of the pre-maintenance vertical profile. A design is produced, which mirrors the profile and this is implemented manually through the tamper’s front tower. Unfortunately, this crude overlifting process fails because the tamper effectively smoothes out what it sees as faults.

DOL® - the solutionAEA Technology Rail’s DOL® uses a lift/settlement model developed from extensive site trials. The DOL® model is embedded in AEA Technology Rail’s ATTA® software and can be incorporated into other sophisticated tamper control systems.

Although DOL® uses more ballast than simple smooth lifting, the cost of the extra ballast must be offset against the savings, which DOL® will no doubt yield.

Clearances and Fixed PointsThe greater lifts generated by the DOL® process could cause problems where there are limited clearances. ATTA®, in its DOL® mode, (or other suitable tamper control systems) can handle tied point situations with ease. The operator will enter the location of the limiting features during the tamper’s measuring run and this will ensure that these points are honoured as the design process takes place. Obviously limiting the DOL® process in this way will compromise its effectiveness. However, by their nature, clearances have to take precedence.

Stoneblowing provides improved track levelling and alignment February   2003

Increasing traffic loads cause vertical and horizontal movements in track ballast to occur, largely as a result of deformation and densification of the ballast. Eventually, speed restrictions

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have to be imposed or maintenance carried out. Eric Russell reports on new research into ballast and track maintenance.

Today's railway operations place greater pressure on track ballast than ever before. It is not only faster trains with heavier payloads that create this extra pressure, but commercial aspects. There is less time to maintain track, the cost of renewing ballast eats noticeably into operating profits and the quality of ride has to meet increased customer expectations.

This has led to a great deal of research into ballast. One leading light, Professor W F Anderson, professor of geotechnical engineering at the University of Sheffield, in the UK, has recently concluded successful trials on a way to automate this aspect of track maintenance.

Densification arises as the bed compresses because particles reorientate and settle; and as abrasion occurs at contact points and reduces particle size. But the more abrasion that occurs, the larger the area of particle contact becomes and the settlement rate drops.

Trains subject the track structure to repeated loading and unloading as they pass. Each load-unload cycle causes deformation of the ballast, part of which is elastic and recovers; while part suffers permanent deformation. A higher degree of permanent deformation takes place when the ballast is wet.

The stresses on a sleeper rotate as a train passes and are complex. The force passes across the sleeper and varies as the train approaches and then leaves the sleeper. When the train is accelerating or decelerating, or on curves, the forces fluctuate.

Track maintenance

When track settles too far, it has to be lifted and the supporting ballast replaced. Originally, sleepers were raised by hand and fine aggregate hand-shovelled into the void with minimal disturbance to the existing ballast.

Later, tamping and lining machines were developed to bring track back to its correct level and alignment. The tamper lifts a sleeper and then inserts metal tines into the ballast bed either side of the sleeper. The tines are vibrated and forced together, pushing ballast under the sleeper and supporting it at the required level.

But this process disturbs and dilates the densely packed ballast and the subsequent rail traffic causes the track to return to the lower level, a phenomenon known as ballast memory. The decay in track bed geometry gets faster with each cycle of maintenance while the tamping damages the ballast and the track eventually has to be renewed completely.

Other methods for reviving ballast have been suggested but most result in the ballast returning to its original level relatively faster than it collapsed before.

Today's answer is the stoneblower, a computer controlled and mechanised version of the process that preceded tamping. It lifts each sleeper and pneumatically injects ballast into the void underneath.

This technique minimises disturbance to the existing ballast, which will have become well compacted over time.

In operation, the stoneblower makes two passes over the track to be maintained: the first is to measure level and alignment; and the second to inject 20mm angular stone through tubes into the void beneath the sleeper using compressed air.

After the first pass, the machine's computer carries out a design process and works out the necessary lift and quantity of stone to be injected to suit the track use. This is checked by the train crew before the second pass.

In some cases it has been possible to extend the interval between maintenance runs by 500 per cent using a stoneblower instead of traditional methods.

Research project

Professor Anderson's research covered the amount of stone that needs to be injected under the sleeper to obtain optimum performance of the track bed afterwards.

He says a number of parameters can be used to describe track geometry. The main ones are the

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vertical profile, commonly called the level, top or surface; and the horizontal profile, called the alignment or line.

Fluctuations in both planes can be considered as waves. At low speeds, the short wavelengths control passenger comfort; but, at higher speeds, the longer wavelengths become more critical.

Stoneblowing creates a two-layer ballast bed and the size and type of the injected stone and the thickness of the injected layer are critical in determining the postmaintenance behaviour.

Ideally, the ballast is hard, angular, single-sized crushed rock which is resistant to breakdown by attrition and allows water to drain easily through it.

Stone size compared to sleeper lift is also critical. If the sleeper is raised by the same amount as the stone particle size, the stone will be confined by the sleeper because there is no lateral pressure to displace the stone, but if there is a greater depth of added ballast than the particle size, then the stone can move laterally at the edge when under load.

This means the stone around the edge of the sleeper cannot take any load and the material in the middle of the sleeper must carry the entire load. This increases the stress on the ballast directly under the sleeper and causes compression.

Maintaining the track and bed is more difficult where lines carry a variety of traffic from high speed passenger trains to low speed heavy goods. Each results in a different load-unload cycle. Track maintenance periods can be extended where only one type of train uses the track.

Besides the vertical considerations, sleepers have to be constrained laterally, to prevent sideways movement of the track.

The lateral strength of a railway track is to a large extent defined by ballast lateral resistance. For a newly laid track or after full maintenance, ballast particles are not well enough consolidated and lateral resistance is low.

This may mean train speeds have to be restricted. But, as the ballast becomes more consolidated and its lateral resistance increases, speed limits can be released.

Research technique

Dr Valeri Markine, assistant professor in road and railway engineering at Delft University of Technology, says a technique for identification of ballast lateral resistance parameters has been developed at the university. It enables speed limits to be accurately determined, so there is the least disruption to train services.

The technique makes use of a tamping machine, which, instead of lifting, shifts a track frame in the lateral direction.

The force needed to move the sleeper against the resistance of the ballast is measured and converted into speed limits for different train types.

Use of simulation software such as finite element analysis (FEA) could provide a useful analytical tool to model track degradation. It could reproduce the load transfer mechanism from rail to ballast layer to the ground formation. This would help quantify such issues as the effect of soft clay consolidation on load redistribution and associated track deformations.

Environmental concerns will also be addressed. There is growing resistance against quarrying new aggregates so recycling existing ballast will have to be considered.

New materials could also improve track bed performance. Geotextiles are widely used in tunnels and other construction to help drainage and this could apply to railways.

If geotextiles are manufactured as geogrids, they can be used as reinforcements to improve ballast stability. The technique is already proven under roads and tracks and has helped increase the steepness and stability of motorway grassed embankments so they take up less space as one example.

In these days of new and improved materials, plus the technology that still has to be commercially developed, there could be alternatives to stone ballast that could also provide new ways to recycle some materials.

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Sleeper review

It may also be possible to redesign the sleeper concept to improve the load transfer between rail and ballast and to make realignment and maintenance easier.

A business such as the Railway Infrastructure division of Patil Group in India has experience of many types of sleeper and has supplied over six million railway sleepers.

The group has a research and development facility that has produced such items as pre-stressed concrete dual gauge sleepers, so standard and broad gauge trains can run on the same track; points and crossing sleepers for high speed trains; guard rail sleepers, used at the approaches to bridges in order to protect a derailed vehicle; pre-stressed concrete sleepers for switch expansion joints on long welded rails; and ballast-less sleepers.

Currently, Patil Group is deploying an innovative technology to manufacture synthetic sleepers. These use elastomers and thermoplastics obtained from the recycling of waste material and meet the technical requirements of wooden sleepers.

It is adding to its experience of concrete sleepers through a new mix that reduces cost and improves durability. It adds a fly ash-based product called a Composite Mineral Admixture. This can replace 20 per cent of the cement in a conventional sleeper.

While these developments continue, it is interesting to note that today's modern railways still depend for their support on a system that was invented for the earliest tracks.

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Track Ballast

(click on image to view Ballast from Cloburn Quarry being loaded at Millerhill LDC)

From supplying a minor local rail siding with track ballast in 1985, we completed the successful start up of Carlisle LDC, developing this Railhead transfer site for long term use by Network Rail, and are now currently operating a similar LDC at Millerhill, near Edinburgh, for the supply of Track Ballast, with Link-up approval (no. 16765).

REASONS TO USE TRACK BALLAST FROM CLOBURN QUARRY

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        • No 1 in Strength - (low LAA, less fragmentation)

      • No 1 in Durability - (low Micro Deval, less wear)

      • No 1 in Density - (lighter, goes further)

 

    Stoneblower Aggregate

(click on the image to see for yourself the quality of Cloburn Stoneblower Aggregate)

 

The request in 1998 for a stoneblower aggregate, with a very high specification encouraged us to develop equipment that produces this material to this exacting specification. The acceptance of this material as superior to all others is recognised by all Infrastructure Maintenance Contractors throughout the UK

      • Double Washed

      • Double Screened

This source provides the highest quality material available for this cost effective track maintenance operation.

Supplied throughout the UK to all IMC`s

CLOBURN QUARRY is located in the beautiful countryside near Edinburgh, Scotland's famous Capital City. 

The quarry, which is over 100 years old, is a large deposit of uniform, bright red granite and is the only one of its type. 

The rock is extremely hard and durable, and as such, it is ideal for use in concrete products and asphalts, and has massive reserves, guaranteeing continuity of supply.

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The Quarry Process: for the purposes of this narrative, the process begins with blasting, however, there are several stages a quarry operator must go through before reaching this point. A few of which are:

1    Conducting geological surveys to test the availability and quality of the rock.

2    Obtaining permits from the Local Authority, with particular reference to reduction of any environmental impact of the operation and restoration works.

3    Removing overburden (soil) to uncover the rock.

(click on the images to enlarge)

Blasting:

A selected blast site in the quarry area is drilled to create multiple bore holes and filled with explosive material. 

 

 

Cloburn Quarry uses state-of-the-art explosives and blasting technology to initiate the first step in producing crushed stone with an approach, which focuses on safety, the environment and efficiency.

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Excavation and Hauling:

The blast fragments the rock into sizes small enough to load 

 

and haul to the primary crusher,  

 

a Kue Ken "Big Bite" crusher, the first one to be commissioned in the U.K..

 

 

Crushing and Screening:

After going through the primary crusher, the rock is further re-crushed using state of the art computer controlled crushers from world leading manufacturers such as Nordberg and Allis Chalmers, 

 

and sized through a series of screens, imported from Austria, to consistently produce aggregates of the finest quality available.

 

 

 

Stockpiling:

After final processing the aggregates are conveyed to numerous stockpiles. Cloburn can process up to 10 sizes simultaneously.

 

 

Loading and Weighing:

Trucks are loaded with the finished product by a wheel loaders, equipped with weight monitoring equipment,

 

 

which, then proceed to the weighbridge for final processing.

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Onward Transportation:

While the bulk of the material from Cloburn is hauled by road, an increasing amount is now transported by rail, and recent developments at Leith Docks, Edinburgh allows us to reach the markets of Europe by sea freight.

Another satisfied customer - the Quarry Process is now complete!

Tamping machines Over time the constant movement of traffic over the track causes gaps to form in the ballast structure known as 'voids'. Often, from the trackside, sleepers can be clearly see bouncing up and down as the wheels pass over them. Excessive movement is dangerous, of course, so the voids need to be filled to give a firm base for each sleeper. This has been done in the past directly by manual labour but today is done by the tamping machine

The tamping machine works by vibrating the ballast and forcing it under the sleeper. These combined actions cause the ballast to form a close matrix which can support the track effectively.

The original Matisa Standard Tamper was totally mechanical with screws providing the in and out movement of the tools and a cam mechanism providing the vibration. Over time some of these these functions were provided by hydraulics.

This is a standard tamper in Australia. As I remember them, Standard Tampers were more enclosed but maybe this model was made specially for the warmer climate.

The man at the controls was actually a fitter at the Adelaide depot. I met him there. He is seated in the travelling position at the rear of the machine, where he could see to drive in both directions.

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The operator is now seated in the working position where there was an excellent view during tamping.

The tamping arms, actuating screws, eccentric bearings for vibration and the flywheels can be seen

This is a view of the Standard Tamper from the operating position.Note the very comfortable seat !

The operating levers can be seen at each side.

"The Matisa Light tamper BL-09 M"After the Standard tamper there were a succession of heavy tamping machines employing a variety of methods of tamping, but all adhering to the basics of pressure and vibration to move the ballast. And these machines were made in a variety of wheel gauges and modified where required for local conditions.

It became apparent that there was a need for a smaller and cheaper machine for small jobs. And so the Light Tamper was born.

We made a considerable number in our Chertsey, UK, factory from about 1956 Starting with our parent company's drawings (metric units and French text) we had to convert to Imperial measurement and source components in the UK as far as possible. Steel and other specifications had to be carefully looked into, but we got there in the end.

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The Light Tamper was intended for working in small sites, such as marshalling yards, although it could also be used anywhere where speed of operation was not the prime consideration.

It started as two separate tamping heads on a trolley that was pushed by two operators, but was later used with a motorised trolley.

The machine was powered by two diesel or petrol engines, one for each tamping head, but one was also used to provide traction.

DetailNote the drive to the belt-driven eccentric flywheel that imparted vibration to the tamping heads. And the hydraulic traction motor.

 

The Light Tamper could be used on secondary track and off-tracked when necessary.

"The JackPak"We did a lot of designing and manufacture at the Chertsey, UK, factory, including the 'JackPak'. This was a tamping machine designed for high lifting, such as in laying or relaying track.

The tamping heads were based on the proven Light Tamper heads and it would run in either direction at about 20MPH. Hydraulic power controlled by electronics was used throughout.

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I do believe that's me, over 40 years ago, testing the JackPak on our works track.

That track took a hammering!

This view clearly shows the sleepers being lifted clear of the ballast while the vibrating tools force the ballast up under the sleeper being processed. The machine was capable of much higher lifts than shown.

Levelling of the track was taken care of by the large oil-damped pendulum at the front of the machine, and a telescope could be used on the targets at the front of the machine to ensure a constant height.

Later tamping machines combined lifting, levelling and aligning functions to enable track to be set geometrically correct before tamping. Of course it still needed human intelligence to programme the machine.

"The Matisa BNR-60 circa 1960"

These machines moved and stopped at each sleeper to be processed which involved a lot of energy as the machine is first accelerated, then braked. Nevertheless they could tamp sleepers at up to 15 a minute although this slowed to 11 sleepers a minute when levelling and llining were also employed.

Today some machines carry their tamping heads on a constantly moving carriage which cuts out the acceleration and braking. By using two sets of tamping heads on the carriage two sleepers at a time can be processed.

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Speed in tamping is important because it allows more track to be processed between trains.

"Stoneblowers" This is a new concept by a USA company, Harsco Corporation. Nozzles are inserted into the ballast on either side of a sleeper, the sleeper is lifted slightly and air is blasted horizontally to blow ballast under the sleeper. It's claimed to be 3 to 5 time more effective than conventional Tamping. A number of these machines are in service on British railways and so far 6,500 miles of track have been processed. Learn more from the Harsco website . Products and Services > Click on Stoneblower

Click to download video (190 KB; needs Windows Media-player or similar)

I think it's true to say that the jury is still out on the efficiency of Stoneblower but it's an interesting concept capable of development.

The Stoneblower is a new machine developed specifically as an alternative to traditional tamping methods for the restoration of track's vertical and lateral alignment. The machine utilizes a process which pneumatically injects ballast under the tie to achieve track positioning to an accuracy of 1.0 mm without disturbing the pre-existing compacted foundation. The result is a smooth track surface which is immediately available for unrestricted line speeds. The Stoneblower is the culmination of many years of research and development by Harsco Track Technologies, Inc. in cooperation with Railtrack plc (U.K.) and British Rail Research (AEA plc). The machine has undergone extensive testing to meet demanding requirements and has demonstrated the ability to significantly extend the time required between track maintenance cycles.

Stoneblower Special Features

Complete vertical and lateral track design capabilities. Automatic indexing with two ties treated simultaneously. Automatic tie position sensing. Computer accessed calibration routines for reference system, workheads and

stone supply system. Dual encoder system for distance and feature recording. On-board crane loads

machine completely with stone in less than one hour. Complete track recording system. Operator interface via touch screen monitors. Diagnostic system to monitor all machine functions including drive and stone

supply system. Paint marking system.

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Designed and manufactured to rigorous reliability standards to ensure required machine availability and reliability levels.

Measurement

The machine travels over the site at up to 10 mph measuring the pre-maintenance condition of the track.

Design

On-board computers use the data collected during the measurement process to determine the profile of the track and calculate the required lift, slew and stone quantity for each tie. The design uses a pre-selected track quality level to minimize lifts and the quantity of ballast required.

Maintenance

The machine moves down the track, in the opposite direction to measurement, treating each selected pair of ties simultaneously. At the completion of maintenance the machine produces a record of pre and post-treatment track quality. The resultant condition of the track is generally suitable for immediate unrestricted line speeds.

Stoneblowing Advantages

 

I. Demonstrated Durability - After stoneblowing, the track remains in position on the average four times longer than track maintained by traditional tamping methods because the existing compacted foundation beneath the ties is undisturbed. Figure 1 shows the improvement in durability for the stoneblowing process. This figure was compiled from United Kingdom track data and shows the in-crease in time between maintenance cycles varying from five-fold improvement for track requiring tamping every six months to a two-fold improvement for track requiring tamping every thirty months.

II. Increased Productivity - The Stoneblower's track design system targets only sections that require rectification and does not treat track with acceptable pre-maintenance quality. For this mode of operation, production rates can exceed 900 meters per hour with rates in typical stoneblown sections averaging 440 meters per hour.

III.  Improved Ballast Life - Stoneblowing is significantly less damaging to ballast as compared to normal tamping methods. Tests conducted in the United Kingdom and

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repeated in the United States have verified reduced ballast degradation. Up to 4 kg of fines per tie are produced by one tamping insertion while only 0.5 kg of fines per tie are produced by an equivalent stoneblowing cycle. Figure 2 illustrates the difference in ballast damage per tie for a total of ten tamping vs. stoneblowing insertions.

IV. Unsurpassed Quality

Track immediately opened at line speed after stoneblowing. On-board diagnostic systems monitor quality during operation. Post-maintenance record of quality immediately available.

Stoneblower General Specifications

Average Output - 440 meters / hours (1,400 feet / hour) Gross Weight - 113 tonnes (124 tons) carried on three bogies Maximum Axle Load - 18 tonnes (20 tons) Length - 32.2 meters (106 feet) Travel Speed - 100 kph (60 mph) maximum Measuring Speed - 16 kph (10 mph) maximum Engine - Cummins KTTA19C, 522 kilowatt (700 horsepower) Ck 1,950 rpm Auxiliary Power Unit - Cummins 4133.9 diesel, 28 kilowatt electrical output Track Lifting - 0 to 80 mm (0 to 3.2 in.) Track Slewing - 0 to 80 mm (0 to 3.2 in.) Minimum Working Radius - 150 meters (500 feet) Fuel Capacity - 4,500 liters (1,200 gallons) Hydraulic Tank Capacity - 950 liters (250 gallons) Stone Capacity - 16 tonnes (18 tons), Size #6-approximately 20 mm (0.8 in.),

LA Abrasion Index 11-19 Stone Delivery - 0.5 to 22 kg (I to 48 lb.) per tie end Automatic Index Distance - 1 tie pair Index Time - 3 seconds Blowing Time - 3.0 to 11.0 seconds

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Back

Why are Ballast Cleaners needed?When a track has been laid for some time, the regular passage of traffic will have eroded the corners of the ballast, and the detritus thus formed will have clogged the ballast, spoiling the drainage and possibly causing the track to become water-logged. In addition, soil from the substratum would have forced its way upwards through the ballast, adding to track deterioration.

Track in this state needs constant attention to keep it within acceptable safety limits and this becomes uneconomic.

One way to remedy this is to dismantle the track and rebuild fron scratch, but this is very costly, particularly in these days of continuous welded track and heavy reinforced sleepers. So that's where the Ballast Cleaner comes in. It cuts the ballast from under the track, and processes it before replacing some under the track and rejecting the rest.

HARSCO TRACK TECHNOLOGIES - RAILROAD TRACK CONSTRUCTION MACHINES, RAIL GRINDERS AND RAIL TRACK MAINTENANCE SYSTEMSHarsco Track Technologies (HTT), Harsco Corporation is a major international supplier of track construction and railroad maintenance equipment to the world's railways. HTT is ISO 9001-2000 certified.

We are a single source for more than 140 types and models of work equipment for track and structure maintenance, track renewal, and new track construction. Harsco Track Technologies designs and manufactures an extensive line of equipment, including HY-Rail® guide wheel attachments (road / rail), rail grinders, tamping machines, utility track vehicles (UTVs) and ballast regulators.

Major railway contract services include rail grinding, new track construction, track renewal, tie plugging, track and turnout undercutting, and tie replacement, plus rail renewal and tie pad change-out services. The range of small tools and equipment continues to carry the Permaquip trademark.

Harsco Track Technologies is positioned to develop and deliver new ideas for maintaining track structure around the world. We provide engineering, sales, parts, service, and maintenance from five main locations in the United States, England and Australia. Sales representatives are located in 11 North American cities. Export agents reside in 27 countries covering the globe. For ongoing support, 21 service locations are available.

NEW TRACK CONSTRUCTION MACHINE

HTT's new track construction machine lays new track on a previously prepared roadbed in a continuous operation. A self-propelled gantry, requiring one operator, keeps the ties supplied to the conveyor systems.

After being deposited by the gantry, the ties move via the conveyor system to the tie drop area. Prior to being positioned on the roadbed, cushioning pads are placed on the ties to cushion the effect of steel rail on concrete ties. Rail, which has been previously distributed along the roadbed, is threaded through guides located at the rear of the tow unit. It its

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then guided inward to a gauging station. Final placement of the rail on the new ties is controlled by an operator who guides the rail onto the tie seat. The operator is also responsible for the proper alignment of the track. This system installs an average of 500 ties per hour.

PRODUCTION RAIL GRINDER

HTT's production rail grinding fleet is composed of high-performance rail maintenance units in several configurations from 72 to 120 stones. All units are self-propelled and offer computer-controlled flexibility for complete pattern capability across the spectrum of railhead configurations. All units offer pattern variety and fast response time in adjusting patterns and reversing grinding direction. Self-contained vacuuming systems control grinding dust.

SWITCH AND CROSSING RAIL GRINDER

Harsco Track Technologies' rail grinders are divided into two families: switch and crossing / transit grinders and production mainline grinders. Many configurations are available for each type of grinder. Specialized rail grinders have been built ranging from 2 to 120 grinding heads. C model grinders are available in 10, 20, 30 and 40 stone configurations.

Major features include: up to 100km/h (62mph) travel speed; integral dust collectors on each grinding car; low noise levels; towable in train formation; adaptable to fit various track gauges and easy operation via a touch screen control panel.

STONEBLOWER

The Stoneblower is a revolutionary machine developed specifically as an alternative to traditional tamping methods for the restoration of the track's vertical and lateral alignment.

The machine utilizes a process which pneumatically injects ballast under the tie to achieve track positioning to an accuracy of 1.0mm without disturbing the pre-existing compacted foundation.

Stoneblowing improves the ballast life due to being significantly less damaging to ballast as compared to normal tamping methods. Tests conducted in the United Kingdom and repeated in the United States have verified reduced ballast degradation.

Track can be immediately opened at line speed after stoneblowing. On-board diagnostic systems monitor quality during operation. Post-maintenance record of quality is immediately available.

TRACK RENEWAL SYSTEM - TRT

HTT's track renewal system - TRT - removes old sleepers and rails, prepares the track bed for new sleepers, lays new sleepers and threads in new rail in one continuous operation and in one pass. It can be ready to begin work within minutes of arriving at a properly prepared work site. This machine also removes and collects the spikes and rail anchors, heats the rail with optionally available rail heater, and can apply various types of rail fastenings depending on customer requirements

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