Advances in rail grinding

Written by Mischa Wanek-Libman, editor
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Rail grinding service providers look to supply precise, efficient and flexible equipment.

Rail grinding service providers look to supply precise, efficient and flexible equipment.

As technology advances to help find rail defects and compare existing rail profiles to ideal profiles, so to must grinding equipment advance and evolve to provide the proper amount of metal removal, operate efficiently to match traffic density and offer the flexibility needed to match heavy-haul and transit needs.

New partnerships
“Precision and efficiency are critical elements of a rail grinder,” said Siddarth Srinivasan, Harsco Rail associate product manager. “The key to a successful grinding program is to be able to maintain optimal wheel-rail interface by taking off a minimum amount of metal from the rail. Harsco grinders feature individual head control on each of the machines’ motors. Individual Head Control combined with the lateral shift capability allows Harsco grinders to provide a superior level of precision with regards to targeting the various parts of the rail. This even applies to the most intricate locations, such as in a switch, crossings or behind guard rails. The ability to achieve Harsco’s grinding accuracy is further enhanced by the Jupiter Control System. The combination of these provides high efficiency, thus, minimizing the number of passes required to do the job.”

RailWorks Maintenance of Way, Inc., is utilizing Harsco Rail switch and crossing grinders equipped with cutting-edge technology to provide rail grinding services within the North American market. A special team, led by RailWorks operating personnel with Harsco technical support,is now working for a Class 1 railroad as part of a multi-year agreement.

“Our goal is to deliver a good value with exemplary service, all done safely,” reports R.T. Swindall, vice president of RailWorks Maintenance of Way. “Right now, we are fine-tuning our operations to ensure a proper start-up. That involves ongoing communications with our customer to understand their expectations and find out what we can do to meet those 100 percent.”

Breadth of service
John Simmons, marketing specialist for Loram Maintenance of Way, Inc., says grinding is one of the company’s core competencies and it offers a wide range of projects to serve all facets of the market.

“Our product depth and ability to respond to customer needs continues to drive strong product demand both domestically and globally,” said Simmons.

Loram’s product range includes the RG 400 Series – Heavy Haul, C44 Series – International, RGI – International, RGS – Specialty and the L Series – Mobile/Specialty/Transit. Simmons points to the success of the 400 Series Grinder, citing value, which has led to strong demand among heavy-haul railways in North America, South America and Australia. The company says its RGS Series provides customers with specialty grinding needs optimized productivity, reduced cost and increased asset life of switches and crossing rail. Simmons says the RGI Series and C44 Series offer the latest technology to handle those markets with restrictive clearance and axle weight, while the L-Series Grinder provides a robust and truckable option.

For Loram, any rail grinding program begins with a good pre-inspection. Rail profiles are measured in a rail inspection vehicle and compared to a pre-determined optimal template. The profiling needs are combined with a depth of cut as a result of an assessment of surface condition to develop a grind plan, including speeds, grind motor locations and number of passes required. This information is then fed into the rail grinder. Simmons says the grinding itself is computer-controlled and regularly calibrated to ensure accuracy. The horsepower of the grind motors adjusts as the machine speed varies due to restricted speed conditions and other factors to maintain a consistent metal removal rate. Loram’s large grinders all feature an onboard profile measurement system to check compliance to the optimal profile, along with a dualencoder/GPS location system that automatically selects the proper template for the track location. The grind and profile data is stored and available for future reference.

“This process is refined by continuing to study the deterioration of rail and causes for variation and incorporating those findings into the decision-making process,” said Simmons. “Numerous test sites are evaluated along with vast amounts of data collected from every Class 1 railway in North America. Refinements in the grind plan development process continue to improve the ability to achieve the profiling and metal removal objectives at the maximum efficiency.”

Simmons notes that as traffic density continues to increase, it is critical to get the work done as efficiently as possible.

“We foresee continued movement toward precision in achieving the desired profile and removing the fatigued metal, all while removing as little metal as is required at the fastest speeds possible. Less metal removed artificially through grinding leaves more of the rail head and extends the life of the rail, provided adequate metal is removed to accomplish the objective. Precision is required to ensure this is the case. Less metal removal required allows even faster speeds, fewer passes, less time spent in a block and a lower cost per track mile. Speeds will continue to be limited by the need to provide precise profiling of the rail, as well as line of sight requirements for machine operation,” said Simmons.

Increasing production
Orgo-Thermit, Inc., (OTI) continues to gain new grinding clients.

“We have developed new stone formulations that allow us to grind embedded track, in the tightest of curves, as well as grinding open track. These stones are performing extremely well. The grinding crew is able to reduce the number of passes in half, solely because of a more efficient stone,” said Pete Capiak, rail grinding supervisor.

OTI says its machine has realized increased production because it can operate continuously on curves, tangents and switches. “This allows the VM8000 Grinding Unit to grind very tight into and through a switch. Just by having the ability to perform this action, we gain increased production, by not breaking the switch into sections,” said Capiak.

He continued by saying precision has always been a selling feature of the VM8000, which is operated remotely from outside the cab allowing the operator complete view of what is happening.

“Being able to make adjustments on the fly helps tremendously. While available track time is continually shorter and shorter, our crew must make a critical decision on how and where to start the grind. This is insured by repeatedly grinding the same way every time, for certain applications. However, in being able to fine tune stone placement, it creates a finish like no other. We use profile gauges to check the work. While the Wheel to Rail Interaction theory is becoming more common place, Orgo-Thermit has embraced it and can continually grind to a template every time,” said Capiak.

When it comes to efficiency, Capiak credits the capabilities of the machine, but also says understanding production rates and following a grinding plan can increase efficiency.

“Going out and grinding in various areas all over the system, may help immediately, but over time, you will need to eventually tie in those unground areas. The VM8000 grind will last a long time, therefore, spending the time to complete a large area will help in coming years,” said Capiak.

OTI notes the machine’s hi-rail capability is helping to meet demands of transit systems and the company is developing a specialized trailer to move the hydraulically-driven machine around quickly to aid grinding on larger systems.

“As the Orgo-Thermit team continues to succeed and provide quality rail grinding services, we take pride in building relationships with both new and long term clients and working with them to have a successful campaign, every time,” said Capiak.

Machines with flexibility
Ron Martin, vice president and general manager of Vossloh Rail Services, says advancements in the area of grinding are always being researched.

“There are great strides being made in the identification of the issues needing to be addressed to extend rail life, but the processes and methods for correction remain the same,” said Martin.

He notes the company is constantly advancing its present technologies, which include High Speed Grinding and Milling systems for both heavy-haul applications and the newest version, High Speed Grinding-City, for transit and lighter duty applications, which also include some heavy-haul property usage.

“These technologies allow the railroads and transits the flexibility they need to address their specific requirements, whether that be removal of light to severe rolling contact fatigue (RCF), corrugation or simple mill scale removal. The Milling technology was developed to help recover the rail and provide a simple cost-effective method to salvage heavily-damaged or even near abandoned rail, as well as provide regular maintenance. The regular use of High Speed Grinding has proven to be an effective technology to help ensure that RCF won’t get to a critical level and require corrective methods of recovery at all. The monitoring of the effectiveness of these systems is done post work through Eddy Current testing,” said Martin.

Martin explains that Vossloh Rail Services uses numerous tools to enhance the process of High Speed Grinding and Milling to identify what condition the rail needs to be returned in order to achieve the longest life cycle possible, then make sure the actual work has been accomplished correctly.

“With the Eddy Current testing offered by Vossloh Rail Services, the identification of areas in need of this grinding, or milling, is more precise and is also used to validate the defects have truly been removed and cannot cause further damage to the rail in the post process. These processes have proven effective and are used extensively in all our operations. The added capability of providing the programs to manage the scheduling and data collection and interpretation round out what can be provided,” said Martin.

Categories: Ballast, Ties, Rail, ON Track Maintenance, Track Machinery