Beefed up R&D efforts resulting in stronger, more reliable welds.
The industry’s rail weld providers are putting extra energy behind their research and development efforts in order to improve upon existing technology and equipment, as well as develop new implements.
Chemetron Railway Products, a division of Progress Rail Services, acquired the mobile welding units from RibbonWeld LLC in 2012. The company says this addition allows for an expanded product offering and allows a broader mix of welding equipment to match customer requirements.
“Our 110-ton welders are ideal for joint elimination and portable welding and the 180-ton integrated pullers or 72-ton with puller are ideal for rail installation work,” said Mark McLean, manager sales. “We recently commissioned our first track welder. This Cat track-hoe based unit has a self-contained welding system, allowing us to access remote locations for rail and special trackwork welding. The unit has high-speed, hi-rail capability for use in a gang consist.”
McLean points out that Chemetron has also added another train to its welded rail train fleet, complementing the existing fleet and strengthening the company’s capability to provide rail, rail welding and equipment to deliver CWR to customers.
“As part of our continuous improvement process, Chemetron is refining the uniformity of the heat-affected-zone (HAZ), while we continue focusing on reducing the size of the HAZ. These advances will be implemented in both our fixed plant and mobile welding systems. The improved uniformity and reduction in size of the HAZ will extend the life of our welds,” said McLean.
E.O. Paton (Hong Kong) Ltd. is in the final stages of bringing a new narrow profile welding head to market. The weld head is interchangeable with existing Paton containers and will allow welds to be performed within turnouts, crossings and in third rail systems without removing the power rail.
Charles Ewing, managing director, says the machine will offer complete welding of large turnouts in one shift and its compact size will allow more work to be performed during tight work windows experienced on transit systems.
Responding to operational requests, Ewing says the company is refining the design of its high pull, self-shearing (distressing/joint elimination) welding head.
Ewing notes that most customers have the same concerns as they pertain to rail welding: minimum rail usage, narrow heat-affected zone, uniform hardness, lack of grey spots/inclusions and asking to weld to high-speed rail standards.
“Working with our partners in the Ukraine (Paton Welding Institute), processes have been developed to meet the foregoing requests,” said Ewing. “Construction of the machines ensures that the highest standards of alignment are achieved. The processes developed virtually eliminate the grey spots.”
Ewing continued, “Ongoing research is being done in conjunction with our partners (Paton Welding Institute) in Kiev involving rail steel producers. Process design is an ongoing task and follows the new steel technology that is introduced. It is our belief that our welding process is by far the most advanced in the field. More physical field testing is required to supplement the analysis carried out from the weld monitoring systems currently in use. Current physical testing data is being compiled to examine relationships between weld parameters variation and actual bed test results. We maintain close contact with users and report concerns/suggestions to the institute, to help determine the best course of action in coming up with new designs/process.”
Holland L.P. continues the development of its Flash Butt Head Defect Repair Weld, which it says enables its customers to remove and replace a defect in the head of the rail with a rail plug matching the hardness of the rail steel and without disturbing the rail neutral temperature.
“We are continuing to expand our capabilities for flash-butt welding joints in turnouts. Since the turnouts are the more expensive portions of the track structure, it only makes sense to have the highest quality flash-butt welds. Utilizing new equipment configurations will enhance our abilities and improve productivity in this welding application,” said Kevin Flaherty, vice president, maintenance-of-way sales.
Additionally, this year is the beginning of the Holland Turnkey, Engineering & Construction Division, which enables Holland to provide turnkey welding solutions to its customers, such as crop and weld, repair welding, roller line and other applications.
Flaherty points to one of Holland’s core values, improvement, as a driving force behind the company’s quest to better flash-butt welds and applications. He says ongoing improvements include new and upgraded welding control systems, slip detectors and weld process refinements, which all contribute to higher quality finished weld products.
“Our customers continue to request improvements in flash-butt welds that produce lower installed cost, more durable welds (last the life of the rail without surface defects), ability to flash-butt weld rail to frogs and more. Our improvement drive is producing many of these outcomes,” said Flaherty. “Work to reduce the HAZ, harder welds matching the parent rail steel, increased reliability and improving weld quality are areas that Holland continually works to improve.”
Another aspect of continued product improvement is research and development, which Holland believes holds the key to its ongoing success in the rail welding business.
“Holland’s R&D efforts are derived from a myriad of sources. First and most important, we listen to our customers to learn their needs. We work with the rail manufacturers to develop weld programs of all rail types, hold brain-storming sessions both within Holland and outside our organization,” said Flaherty. “We conduct market studies to gather information on rail welding needs from throughout the rail industry, both in North America and internationally.”
Flaherty also notes that Holland encourages and engages in technology partnerships to expand the source of information for rail welding development from beyond the rail industry and gives the example of Holland partnering with the Edison Welding Institute on the development of its Head Defect Repair Weld.
“Holland’s leadership position within the rail welding field has been built upon our continued efforts to improve our technology, process and process control, equipment and quality of the complete flash-butt weld,” said Flaherty.
In 2012, Lincoln Electric began a program partnering with railroad customers to locate manganese welding crews with a basic understanding of welding on manganese frogs and crossing diamonds in regions where training schools were not available.
The company administered two-day classes, one-day classroom, the next day hands-on welding, at more than a dozen locations. These classes trained welders on how to set up the Lincoln equipment at the proper settings, check for trouble spots in the system and tips on how to service every part of the equipment chain. According to Lincoln Electric, application of consumables at the required voltage and the proper technique in welding brought the welders to a higher level of understanding.
In 2013, Lincoln Electric will go to the same locations to elevate the skill to a second level.
“The first time at the locations, we covered basic things,” said Brian Meade, Lincoln Electric’s manager of railroad technical services, global accounts. “We worked hard communicating with our engineers at our main plant in Cleveland, Ohio, and gathered the welders to come up with new techniques and a higher understanding to teach the second time around.”
Meade continued, “We have improved the welding machine, feeding systems, consumables, packaging and have added new products like the Magnum Pro welding gun. These improvements have made it easier for the welders, giving them more of an edge to increase their skill level.”
According to Meade, railroad welding crews in the field have taken advantage of Lincoln Electric’s improvements and training to reduce train delays and make better weld repairs to manganese castings, which will last longer under the increased loading of today’s train traffic.
“The current metallurgical development of rail steels, with high running surface hardness, has made it necessary for Orgo-Thermit, Inc., to develop a suitable Thermit® welding technology, to join these high-strength rail steels and to keep abreast with the current global rail steel metallurgies and latest rail rolling technologies,” said Dave Randolph, president of Orgo-Thermit, Inc. “The industry is demanding a better surface wearing weld that better matches the surface hardness of these high-strength rails, while still maintaining toughness in the base of the weld.”
The company’s answer to the industry need is the patented Head Alloyed Welding (HAW) process, which allows welding of high-strength rails with more compatible weld running surface hardness and a ductile base. According to the company, the welding procedures and tools used to execute the HAW are identical to that of a standard weld, except that a patented diverting plug that contains micro-alloys is used, instead of a conventional diverting plug.
“This feature makes it very easy for the customer to employ the HAW process, with minimal training and no outlay of additional costs for any special tooling. The HAW process is simple and can be performed by any trained welding crew with the current tools they have on their welding vehicles,” said Randolph.
In February 2011, after successful laboratory metallurgical and physical testing evaluations, 10 Head Alloyed Thermit® Welds were installed at TTCI’s Facility for Accelerated Service Testing Heavy Tonnage Loop. Seven of these Head Alloyed Welds were used to join high-strength rails with an initial hardness of around 390 BHN. Two of the Head Alloyed Welds were made in intermediate strength rails with a hardness of 340 BHN and one Head Alloyed Weld was made to join an intermediate strength rail (340 BHN) to a high strength rail (390 BHN).
“Although Orgo-Thermit Inc. does not recommend using the Head Alloyed Welds in mixed strength or standard strength rail welding, this test was performed to investigate how unintended application of the micro-alloyed diverting plugs can affect the weld service performance. Orgo-Thermit Inc. recommends that when welding a high-strength rail to a lower strength rail, the welding portion for the lower-strength rail is used,” said Randolph.
TTCI conducted hardness measurements, visual inspections and longitudinal profiles of the entire weld running surfaces throughout the duration of the test. The Head Alloyed Welds have accumulated more than 324 mgt of heavy-axle-load (HAL) traffic, with no service failures. In the intermediate strength rail (340 BHN); the Head Alloyed weld was significantly harder than the adjacent rail. The Head Alloyed Weld experienced a lower wear rate than that of the rail. The weld centerline of Head Alloyed Welds, employed to join the high-strength rails (390 BHN), have shown approximately 50 percent reduction in wear/batter compared to standard welds, despite any of the Head Alloyed Welds not having received maintenance grinding of any kind since the commencement of the test.
“We believe that the success of our research and development efforts will ensure that our unique Thermit® welding products will have a future in the heavy-axle-load railroad industry, for many years to come,” said Randolph.
Railtech Boutet is focusing its efforts this year on commercializing three new products: The QP Hybrid Welding System, Head Wash Repair (HWR) welding and the Startwel® Ignition System. The three products were created to meet customers’ requests in improving the overall aluminothermic welding process.
“Our patented QP Hybrid molds have been a customer favorite this year and we are working hard on meeting the increasing demand for this product,” said Oliver Dolder, executive vice president and chief operating officer. “The QP Hybrid molds use a compressible lining in order to get a perfect fit on the rail. This allows the welders to make a great quality weld by drastically reducing the chances of any flashing to occur during the welding process which in turn significantly increases the life of the weld.”
Dolder says the company’s HWR weld has found success among customers in the repair of transverse defects, corner gauge defects and minor shelling. He calls the HWR a great “preventative maintenance weld,” which gives the customer an opportunity to repair a small defect before it grows and leads to a break in the rail.
Railtech Boutet notes that its Startwel® Ignition System allows the welder to easily ignite the weld charge to initiate the pour process for the Railtech Aluminothermic Weld System, replacing the traditional “sparkler” igniter design.
“This new electric ignition system is safer than today’s traditional igniters,” said Dolder. “In addition, Startwel® is classified as non-hazardous for transport, therefore there are no shipping restrictions (can be shipped overnight if there was an emergency) and provides more accurate and consistent tap time.”
The company’s trio of new products wouldn’t be possible without the research and development team, which is done by Railtech Boutet’s parent company, Railtech International.
“Between our internal R&D and working closely with our customers, we are able to develop new and innovative products, which have and will continue to improve the aluminothermic welding process,” said Dolder.