Intelligent use of rail grinding

first_imgINTRO: Profiling can prolong rail life, improve ride dynamics and cut maintenance costs if is done carefully; incorrect use of grinding can all too easily have the opposite effects to those intendedBYLINE: Dr Allan M Zarembski PEPresidentZeta-Tech Associates IncMODERN RAIL grinding techniques use carefully applied grinding patterns to profile the rail head, and thus determine where and how wheel/rail contact will occur. Computer control has made possible this fine tuning of wheel/rail contact geometry, which reduces damage to the rail head and thus extends in-service life.Concurrent with the development of rail profile grinding techniques has been a move away from traditional defect elimination grinding – often referred to as ’rail rectification’ – towards rail ’maintenance’ or ’preventive’ grinding. This more recent approach does not wait for surface defects to develop, but rather attempts to eliminate their development before they emerge on the rail head1.This move from defect elimination to maintenance and profile control grinding has resulted in an expansion of the use of rail maintenance grinding techniques, increasing the service life of the rail and therefore reducing its life cycle cost per million gross tonne-km carried.It has also led to improvements in wheel/rail dynamic interaction in both the vertical and horizontal plane, not only extending rail life still further but also improving ride quality, with consequent benefit to the track structure, rolling stock and freight or passengers it is carrying. In addition, lineside residents suffer less noise from passing trains.Grinding has been used to address a range of problems experienced by railways carrying heavy axleload freight and high speed passengers, as well as light rail vehicles. A corresponding range of grinding applications has evolved to deal with problems peculiar to these disparate functions.It must be emphasised that any solutions – in particular profile grinding – are problem specific. The proper grinding profile approach must be used to address each specific class of rail problems, and these are considered in turn.Surface defectsGrinding was introduced originally in the 1930s to control defects such as corrugation on the top of the head. Such defects initiate vertical wheel/rail dynamic activity; correcting them reduces noise, vibration and vertical impact forces.Although this type of grinding has traditionally been remedial, taking place after the defects appear, the subsequent use of preventive maintenance grinding led to better control of these defects and the consequent reduction of their adverse impact on operations and costs. Planned grinding catches these surface defects early in their formation cycle while they are still shallow, thus reducing the dynamic loading damage caused to the rail and track structure.In some cases, the development of surface defects such as the low-rail corrugations often found on freight railroads has been significantly retarded, or even completely forestalled by the use of profile grinding.In modern practice, grinding to control surface defects is frequently combined with profile grinding. Additional benefits have also been obtained by combining profile grinding with the use of improved rail steels (cleaner, higher strength) and/or improved lubrication.Fatigue defectsControlling and maintaining the cross-sectional shape of the rail head, a process known as profile grinding, has been used to limit surface fatigue defects. These include spalling on the gauge corner of the high rail, centre cracking of the low rail in curves, and sub-surface fatigue defects such as gauge corner shelling of the high rail. These classes of defects are commonly associated with heavy axleloads and represent the area of benefit most frequently reported by North American freight railroads2,3.A major objective of profile grinding is relieving high contact stresses at the gauge corner of the high rail associated with discrete single point contact in a severe flanging condition, such as occurs on sharp curves. Fig 1 shows the zone of high contact stress on the gauge corner of the high rail, and associated metal removal during gauge corner grinding. These high stresses can induce fatigue problems including cracking and spalling. Grinding shifts wheel/rail contact away from this corner to a more central location on the rail head.In sharp curves, a second contact point between the flange of the wheel and the gauge face of the rail can occur, generating two-point contact between wheel and rail. Dividing the wheel/rail contact site reduces contact stresses and can result in a decrease in both surface fatigue spalling and sub-surface shelling.This gauge corner grinding approach removes the surface fatigue-damaged rail steel, relocating the (interior) point of maximum rail stress, before fatigue damage can initiate a failure defect. This is particularly important for well lubricated track or premium (high hardness) rail steels where the rate of wear is substantially reduced.However, recent research suggests that changing from one-point to two-point contact can result in a deterioration in bogie curving performance4, with a corresponding increase in the wheel/rail flanging forces. This can increase gauge face wear if no other action is taken. Therefore, this type of gauge corner profile grinding should be used primarily in areas where fatigue, and not wear, is the dominant rail failure mode.Controlling rail wearProfile grinding is also used to improve the steering of conventional three-piece freight bogies, and thus reduce gauge face wear5. This application – initially introduced by the heavy-haul mining railways in Western Australia during the late 1970s – resulted in the development of a set of asymmetric rail head profiles. Separate profiles are used for high and low rails, and for straight track – especially where hunting wear occurs.By making use of the difference between wheel radii due to tread conicity, the bogie can be induced to steer itself around the curve, ideally without flange contact. Fig 2 shows how, after grinding the gauge side of the low rail and the field side of the high rail, the outer wheel is forced to ride on the larger radius portion of its tread while the inner wheel rides on a smaller radius.This has the potential for eliminating flanging on curves of less than 600 m radius, based on 1:20 wheel conicity. This has been the experience in Australia, where increased wear life of the order of 70% to 80% has been reported1.Recent research by the AAR suggests that improved curving can likewise be achieved through the use of a conformal, single-point contact between the wheel and the gauge corner of the rail4. This likewise supports the notion that no single grinding profile can address all of the major rail problem areas. It is necessary to define the specific problem, or class of problems, to be addressed prior to the selection of a grinding profile and initiation of profile grinding.Grinding versus lubricationGrinding is best applied as part of an overall rail maintenance programme which includes effective lubrication, the use of premium rail and defect testing. This is particularly true for the severe rail degradation environment found on moderate and heavy curvature track under heavy freight loading. The objective is to obtain the maximum life from rail in its first position before being downgraded to secondary track.On poorly lubricated track, maximum rail degradation generally takes the form of severe wear on the high rail of the curve, with head wear being the primary factor driving rail replacement. In well lubricated track, rail wear is dramatically reduced. This allows fatigue damage to accumulate because the fatigued steel is not worn away, so surface and sub-surface defects have time to develop, notably at the gauge corner of the high rail6.This relationship between rail life and lubrication is illustrated in Fig 3 which represents the results of controlled testing at the FAST test track at Pueblo, Colorado. In an unlubricated environment, the rail in this curve required replacement after 70 to 90 million gross tonnes (MGT) of heavy axleload traffic. When the rail was fully lubricated the wear rate was reduced by a factor of 10 such that the projected wear life of the rail, under the same traffic conditions, became 900MGT.However, before this extended wear life could be realised, the rail began to experience significant fatigue defects, with the 5% defect level (which corresponds to the point where many railroads replace rails due to excessive fatigue defects) being reached after approximately 160MGT, well before the rail’s potential wear life of 900MGT.If the rail is to approach more closely its wear life potential, cumulative rail fatigue must be controlled. Profile grinding can extend fatigue life by reducing maximum wheel/rail contact stresses and removing fatigue-damaged metal prior to the development of defects. In fact, test data suggests that profile grinding has the potential to extend the fatigue life of curve rail into the 300 to 400MGT range7. This would represent a further doubling of rail life, with major economic benefits. Profile grinding benefitsMaintenance grinding has been shown to increase rail life. This life extension – often observed in conjunction with improvements in metallurgy, steel cleanliness and lubrication – is difficult to isolate. There is no doubt, however, that grinding has been shown to generate measurable extensions of rail life and improvements in rail performance, as well as secondary benefits associated with reduced dynamic wheel/rail loading.While the effect of rail grinding is often masked by concurrent improvements, several railroads have been able to document significant increases in rail life which they have attributed, in very large part, to rail profile grinding. Such was the case on Burlington Northern, where improvements in average rail life of 50% to over 300% were reported; grinding was credited as a key factor3.Canadian National also reported significant life increases, in some cases in the order of 500%, due to a combination of increased lubrication, improved rail steels, and rail profile grinding. CN further reported that if proper grinding was not performed on an ongoing basis, rail could lose 95% of its potential service life2.In the case of CP Rail, the effect of grinding is clearly illustrated in Fig 4. This shows a dramatic reduction in new rail laid during the decade to 1995 which correlates well with the increase in grinding. While other factors such as improved lubrication and metallurgy have contributed, CP also credits rail grinding as a key factor in this dramatic extension of rail service life8.Profile grinding issuesWhile producing demonstrable benefits in terms of extended rail life and reduced damage to track structure and rolling stock, profile grinding does change the wheel/rail contact environment with the potential for undesirable behaviour if not properly addressed.As already noted, moving from one-point to two-point contact can adversely affect curving performance and increase flanging forces4. This in turn increases gauge face wear as well as the potential for rail overturning on curves – of particular concern in an environment where lubrication is absent, or the high rail is lubricated and the low rail is dry which generates high lateral loads.But two-point grinding is most effective in controlling rail fatigue, and the latter may be more important than increased wear. This condition, illustrated in Fig 5, correlates fatigue defects (detail fractures) and rail grinding (pass miles) on BN during 1984-95. Between 1983 and 1988, BN performed profile grinding using a basic two-point contact configuration and thus kept the number of detail fractures low. In 1988-90 BN changed to a lighter conformal grinding pattern with a resulting surge in detail fracture defects as well as a rash of broken rail derailments which cost in excess of $6·5m 9. In 1990-91 BN switched back to more aggressive two-point grinding and again was rewarded by a reduction in detail fracture type fatigue defects.Lessons learnedRail grinding must be used carefully and intelligently. Properly used, it can result in substantial extension of rail life, reduction in track maintenance costs, and improvement in the dynamics of wheel/rail interaction. Improperly used, it has the potential for increasing lateral wheel/rail forces, increasing rail wear, and even causing the low rail on curves to overturn.Grinding must therefore be used with a proper understanding of its benefits and limitations. When used effectively, it is a valuable tool for the control of rail degradation, and for the reduction of overall track maintenance costs. oCAPTION: The Pandrol Jackson RMS-3 belongs to the latest generation of North American high-speed rail grinding machinesCAPTION: Left: Fig 1. Profile grinding of the high rail in a curve to avoid gauge-corner spallingCAPTION: Fig 2. Asymmetric profile grinding increases the rolling radius on the high rail and reduces the radius on the low rail, improving bogie curving performanceCAPTION: Centre: A simple hand-held gauge is used to check the profile of the rail head after grindingCAPTION: Fig 3. Rail failure distribution relative to tonnage carried on AAR’s FAST test trackCAPTION: Fig 4. Correlation between rail replacement and grinding recorded by CP RailCAPTION: Fig 5. BN recorded a surge in detail fractures caused by fatigue when conformal grinding was introducedReferences:1 Zarembski AM. ’The Evolution and Application of Rail Profile Grinding’, Bulletin of the American Railway Engineering Association No 718, December 1988.2 Worth AW, Hornaday JR Jr, and Richards PR. ’Prolonging Rail Life Through Grinding’, Proceedings of the Third International Heavy Haul Railways Conference, Vancouver, October 1986.3 Glavin W. ’Rail Grinding The BN Experience’, Bulletin of the American Railway Engineering Association No 722, October 1989. 4 Hannafious J. ’Rail Grinding at FAST’, Proceeding of the First Annual AAR Research Review, Vol I: FAST/HAL Test Summaries, Pueblo, November 1995.5 Lamson ST and Longson BH. ’Development of Rail Profile Grinding at Hamersley Iron’, Proceedings of the Second International Heavy Haul Railways Conference, Colorado Springs, 1982.6 Steele RK. ’Rail Lubrication: The Relationship of Wear and Fatigue’, Transportation Research Board, Railroad Maintenance Workshop, Amherst, June 1985. 7 Zarembski AM. ’The Relationship Between Rail Grinding and Rail Lubrication’, Second International Symposium on Wheel/Rail Lubrication, Memphis, June 1987.8 Wilson A. ’Developing and Managing Rail Maintenance Programs’, ARM Rail Maintenance Seminar, Chicago April 1996.9 Tornga G. ’Conformal and Non-conformal Grinding Experiences’, ARM Rail Maintenance Seminar, Chicago April 1996.L’utilisation intelligente du meulage des railsCombiner la maintenance du profil avec le meulage pour éviter la dégradation de la surface de roulement, peut prolonger la vie des rails, réduire la maintenance des voies et améliorer la qualité de roulement. Mais il faut utiliser la bonne technique dans chaque cas. Un meulage mal appliqué risque de réduire la vie des rails et d’augmenter les forces latérales entre les roues et les rails au point olast_img read more

DSME scores order to build two LNG carriers

first_imgLNG World News Staff Image courtesy of DSMESouth Korea’s shipbuilding giant Daewoo Shipbuilding & Marine Engineering (DSME) said it had secured an order worth 394.1 billion won ($366m) to build two liquefied natural gas (LNG) carriers.The two LNG vessels are scheduled for delivery by the first half of 2020, DSME said in a filing to the stock exchange.Daewoo did not reveal the name of the shipping company located in the Americas.This is Daewoo’s first LNG newbuilding order for the year of 2018. To remind, in December it won an order worth 430.5 billion won to build a new LNG carrier and a floating storage regasification unit (FSRU).last_img read more

Abuse rate 10 times higher in welfare families: study

first_imgNZ Herald 12 Oct 2012Five out of every six children who are abused or neglected in their first five years are in families on welfare, new research has found.The research, conducted by the University of Auckland for the white paper on vulnerable children, found that 13 per cent of children in families that went on welfare in the child’s first two years were abused or neglected before they turned 5, almost 10 times the rate for children whose parents were never on welfare (1.4 per cent).That meant 83 per cent of New Zealand children who were abused or neglected in their first five years lived in families that were on welfare in the child’s first two years.The finding was based on matching Child, Youth and Family Services data on substantiated cases of abuse or neglect with Work and Income data on children born between 2003 and 2006 who were included in the main benefits of their caregivers.One of the authors, social work lecturer Dr Irene de Haan, said: “The problem is the cumulative stress that arises from people being chronically short of money.I am concerned that the children live in families with chronic financial stress, lack of food, lack of money, constant moving around.”http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10839993last_img read more

Homeless die 20 years younger – study

first_imgNewsHub 20 August 2016Family First Comment: “The findings also showed people who excessively smoke cannabis die earlier than those addicted to alcohol or tobacco.”A new study shows homeless people die 20 years earlier than those living in a home.The study found homeless people in Auckland die at an average age of 63.Researcher Simon Thornley says drugs were revealed as a key factor in the shortened lifestyle.“A lot of them have issues with addiction, whether that’s alcohol, tobacco, cannabis – and I think addiction issues mean that you don’t prioritise looking after yourself,” he says.Mr Thornley adds the findings also showed people who excessively smoke cannabis die earlier than those addicted to alcohol or tobacco.http://www.newshub.co.nz/nznews/homeless-die-20-years-earlier—study-2016082008Keep up with family issues in NZ. Receive our weekly emails direct to your Inbox.last_img read more

Nadal gets 2020 season underway with a win

first_img Read Also: Australian Open: Sharapova says there’s still a lot of fire amid wildcard offer The left-handed Nishioka caused the world number 45 problems and clinched the tie after Go Soeda put Japan ahead with a comfortable 6-1, 6-3 victory over Martin Cuevas, Pablo’s younger brother. Soeda had replaced world number 13 Kei Nishikori, who withdrew from the tournament and the Australian Open with an elbow injury. FacebookTwitterWhatsAppEmail分享 His momentum continued as he stormed out to a 5-2 lead in the second set but was unable to serve it out twice before eventually overcoming Basilashvili’s spirited challenge In the earlier match, Bautista Agut expectedly crushed world number 679 Metreveli, who was playing his first match on the ATP Tour. Metreveli, 26, started enterprisingly and had a golden opportunity to get on the board early but lost a marathon 15-minute second game on serve. It was one way traffic from there as Bautista Agut took command with pinpoint groundstrokes to rattle his inconsistent opponent. “I asked players who knew him for information because I had never seen him play,” Bautista Agut said. “I was focusing on my game and I played a great match.” Japan also started strongly after sweeping Uruguay in the earlier Group B tie. World number 73 Yoshihito Nishioka thrashed higher-ranked Pablo Cuevas with a 6-0, 6-1 rout in just 54 minutes. Nishioka put on a masterclass over a dispirited Cuevas, but was helped by his lacklustre opponent who did not hit a winner during a grim first set. Loading… World number one Rafael Nadal overcame sluggish serving to start his season with a 6-3, 7-5 victory over Nikoloz Basilashvili on the second day of the inaugural ATP Cup on Saturday. The 19-time Grand Slam winner clinched the tie for Group B favourite Spain against Georgia after world number nine Roberto Bautista Agut downed unheralded Aleksandre Metreveli 6-0, 6-0 in 71 minutes. Rafael Nadal of Spain defeated Nikoloz Basilashvili of Georgia on day two of the ATP Cup tennis tournament in Perth Nadal was made to work in the contest lasting one hour and 49 minutes, his first of the season as he eyes equalling Roger Federer’s record Grand Slam tally – of 20 titles – at the Australian Open late this month. “It was a tough first match-up of the season. It was not an easy start,” Nadal said. “I had some mistakes but was able to close it out.” It was his first match since he spearheaded Spain’s Davis Cup title on home soil alongside Bautista Agut in November. “We had great experiences playing on the team and representing our country and here we are again. We want to try our best,” he said. Nadal started slowly against Basilashvili and was broken in the opening game to quieten the near capacity crowd in his first-ever match in Perth. But he bounced back immediately and gained the break with a sizzling winner down the line. World number 26 Basilashvili, who had been soundly beaten by Nadal twice previously, was undaunted and impressively countered on the baseline to stay in the contest. Nadal, however, made his move with a break in the eighth game to gain control and draw first blood shortly after. Promoted ContentThe Very Last Bitcoin Will Be Mined Around 2140. Read More7 Facts About Black Holes That Will Blow Your MindWhich Country Is The Most Romantic In The World?Portuguese Street Artist Creates Hyper-Realistic 3D Graffiti11 Most Immersive Game To Play On Your Table TopThe Highest Paid Football Players In The WorldThis Guy Photoshopped Himself Into Celeb Pics And It’s Hysterical6 Interesting Ways To Make Money With A DroneA Soviet Shot Put Thrower’s Record Hasn’t Been Beaten To This Day7 Non-Obvious Things That Damage Your PhoneWho’s The Best Car Manufacturer Of All Time?6 Incredibly Strange Facts About Hurricaneslast_img read more

Motorcycle pursuit suspect arrested on gun charge

first_imgColumbus, IN—A Columbus man was arrested on several charges Monday afternoon after he reportedly fled on a motorcycle from a CPD officer. At approximately 4:30 p.m., a CPD officer attempted to stop Jayden M. Campbell, 20, of Columbus near State Street and Brooks Street. Campbell increased his motorcycle’s speed and disregarded a nearby stop sign when the officer activated his police car’s emergency lights.A short time later, the officer located Campbell’s wrecked motorcycle near Fodrea Elementary School in an alley near Brooks Street and Kentucky Avenue. During a search of the motorcycle and property left by Campbell, the officers located a loaded handgun with the serial number removed as well as methamphetamine.Campbell was located a short time later outside of a residence on South Hinman Street where he was taken into custody. He was remanded to the Bartholomew County Jail and he is now charged with Possession of Meth, Carrying a Handgun without a License on School Property, Resisting Law Enforcement, and Leaving the Scene of an Accident.last_img read more

Christopher Lee “C J” Carf

first_imgChristopher Lee “CJ” Carf Jr., age 23 of Osgood passed away on Thursday February 6, 2020. CJ was born on January 16, 1997 the son of Christopher Carf and Teresa (Collier) Bruns.CJ grew up in the Holton community along with brothers, Anthony and Charles and sister Melissa. He had attended South Ripley School system prior to entering the workforce. He enjoyed music and playing his video games. He had most recently been employed by Brewer Livestock in North Vernon, IN.CJ is survived by sons Matthew and Coleson, parents Chris (Karyn Meeks) Carf and Teresa (Etta Adams) Bruns, brothers Anthony Carf and Charles Carf, sister Melissa Carf, grandparents Sandra Souder and Lynda Carf, aunt Pamela Furnish, and uncle Craig Carf, along with 3 nieces and 2 nephews. He was preceded in death by his grandpa Ernie Carf and sister Christina Carf.A Celebration of Life will be scheduled at a future date. Memorials maybe given to NAMI Peer to Peer in care of Neal’s Funeral Home. Online condolences may be left for the family at Nealsfuneralhome.netlast_img read more

Decatur County has 19 confirmed coronavirus cases

first_imgGREENSBURG, Ind. – The Decatur County Department of Health announced a total of 19 confirmed COVID-19 cases in the county on Thursday afternoon.The health department published the information on their Facebook page and said “this number only reflects those cases that were sick enough to be tested.”Officials also encourage residents to follow Indiana’s Stay-At-Home orders that were put in place earlier this week.“Families should designate a grocery shopper and let that person shop alone. If you have to do laundry at the laundromat, do it alone. If you do have to go out, maintain a 6 ft. distance between you and anyone else,” the agency wrote on Facebook.last_img read more

Police Blotter 07-20-2020

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Foxes boss Ranieri backs misfiring Martial to find form

first_img United great Paul Scholes criticised the 19-year-old following their PSV stalemate, saying on BT Sport he did not look “bothered” about missing chances. Ranieri understood Scholes’ comments and believes Martial can use the remarks to become stronger. He said: “He is 19-years-old. It is right to make criticism – and Scholes made the right criticism – but it will improve his mind. His character is very strong, he is young, but strong. It is important that he is also intelligent and then he can improve. “I think his impact for us was amazing. He scored four goals if I remember. I have watched him grow a lot since two or three years ago when I bought him from Lyon. Now he is young, but he is a man. “Already, three years ago, he knew very well where he will arrive because his focus was to achieve a high level of football in the world. I think he can arrive.” Leicester host United and Martial on Saturday with the Foxes top, one point ahead of their second-placed visitors. Ranieri added: “It’s the big match of the Premier League this week. We are top of league and in this moment we deserve this. For us, it’s another match to see how we have to improve. When we play great teams, great champions, I have to see how our team show the tactics – how we react if we lose a goal and how we react if we score a goal.” Claudio Ranieri has backed Anthony Martial to come good for Manchester United and brush off any criticism. The Leicester boss signed Martial for Monaco from Lyon in 2013 before United shelled out £36million to bring him to Old Trafford in the summer. He scored four goals in his first four games, but has netted just once in his last 14 outings, drawing a blank in Wednesday’s 0-0 Champions League draw with PSV. center_img Press Associationlast_img read more