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79-541: Up to 80% of the Canadian fleet and 69% of U.S. rail tank cars were DOT-111 type, as of 2013. DOT-111 cars are equipped with AAR Type E top and bottom shelf Janney couplers designed to maintain vertical alignment to prevent couplers from overriding and puncturing the tank end frames in the event of an accident. These tank cars transport various types of liquid dangerous goods , including 40,000 cars in dedicated service carrying 219,000 car loads of ethanol fuel annually in

158-400: A = m 1 g − T {\displaystyle m_{1}a=m_{1}g-T} . In an extensible string, Hooke's law applies. String-like objects in relativistic theories, such as the strings used in some models of interactions between quarks , or those used in the modern string theory , also possess tension. These strings are analyzed in terms of their world sheet , and

237-412: A net force is present in the system. Tension in a string is a non-negative vector quantity . Zero tension is slack. A string or rope is often idealized as one dimension, having fixed length but being massless with zero cross section . If there are no bends in the string, as occur with vibrations or pulleys , then tension is a constant along the string, equal to the magnitude of the forces applied by

316-587: A restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units ). The ends of

395-659: A 122-car train derailed and exploded near Plaster Rock , New Brunswick . Nobody was injured but about 150 people were evacuated. The petroleum products originated in Western Canada and were destined for the Irving Oil Refinery in St. John. The DOT-111 tank cars are constructed with a draft sill design. Draft sills incorporate the draft gear behind each coupler that is designed to transfer longitudinal draft ( tension ) and buff ( compression ) forces throughout

474-468: A Confederate veteran of the American Civil War , invented the semi-automatic knuckle coupler in 1868. It automatically locks the couplers on cars or locomotives together without a rail worker having to get between the cars, and replaced the link and pin coupler , which was a major cause of railroad worker injuries and deaths. The locking pin that ensures Janney couplers remain fastened together

553-420: A derailment incident near Westree, Ontario which occurred on 30 January 1994. They cited report NTSB/SS-91/01 which questioned "the safety of DOT-111A tank cars and determined that this classification of tank car has a high incidence of tank integrity failure when involved in accidents and that certain hazardous materials are transported in these tank cars even though better protected cars (less liable to release

632-488: A frictionless pulley. There are two forces acting on the body A: its weight ( w 1 = m 1 g {\displaystyle w_{1}=m_{1}g} ) pulling down, and the tension T {\displaystyle T} in the string pulling up. Therefore, the net force F 1 {\displaystyle F_{1}} on body A is w 1 − T {\displaystyle w_{1}-T} , so m 1

711-547: A horizontal gap and a vertical hole in the knuckle itself to accommodate, respectively, a link and a pin, to enable it to couple to vehicles which were still equipped with the older link-and-pin couplers. The knuckle coupler has withstood the test of time since its invention, with only minor changes: Bazeley Coupler 1905-1918 M.C.B. D Type established as the Universal M.C.B. Standard, Adopted 1915 Arthur James Bazeley (1872-1937), railway couplings inventor/design engineer;

790-705: A net force somewhere in the system. In this case, negative acceleration would indicate that | m g | > | T | {\displaystyle |mg|>|T|} . ∑ F → = T → − m g → ≠ 0 {\displaystyle \sum {\vec {F}}={\vec {T}}-m{\vec {g}}\neq 0} In another example, suppose that two bodies A and B having masses m 1 {\displaystyle m_{1}} and m 2 {\displaystyle m_{2}} , respectively, are connected with each other by an inextensible string over

869-454: A net force when an unbalanced force is exerted on it, in other words the sum of all forces is not zero. Acceleration and net force always exist together. ∑ F → ≠ 0 {\displaystyle \sum {\vec {F}}\neq 0} For example, consider the same system as above but suppose the object is now being lowered with an increasing velocity downwards (positive acceleration) therefore there exists

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948-503: A patent search under "Bazeley, railway couplings" or "Arthur James Bazeley, railway couplings patents" which have been drawn/filed and provided by Roger Bazeley-USA, MSTM, MSID, CHSRM Mineta Transportation Institute , Transportation Industrial Designer. A.J. Bazeley Railway Coupling, Construction/Design Improvements and Draft Rigging related patents include: US 1193222, US 124622, US 1932719, US 1518299, US 1932503, US 2235194, US 1932440 and others. National Malleable Castings in 1891 absorbed

1027-573: A retrofit of the top fittings of all Class 111A cars would exceed one billion dollars. The Transportation Safety Board of Canada (TSBC) investigated an occurrence near River Glade, New Brunswick which occurred on 11 March 1996. The 1996 report concluded that "Class 111A tank cars are more susceptible to release product upon derailment and impact than pressure tank cars, and yet there are a number of toxic and volatile liquids that are still permitted to be carried in minimum standard Class 111A tank cars." The report makes no recommendation to upgrade or limit

1106-607: A semi-automatic form of railway coupling that allow rail cars and locomotives to be securely linked together without rail workers having to get between the vehicles. Originally known as Janney couplers (the original patent name) they are almost always referred to as Knuckles in the US and Canada (regardless of their actual official model name, nowadays generally various AAR types in North America), but are also known as American , AAR , APT , ARA , MCB , Buckeye , tightlock (in

1185-429: A string or other object transmitting tension will exert forces on the objects to which the string or rod is connected, in the direction of the string at the point of attachment. These forces due to tension are also called "passive forces". There are two basic possibilities for systems of objects held by strings: either acceleration is zero and the system is therefore in equilibrium, or there is acceleration, and therefore

1264-560: A string with tension, T , at a constant velocity . The system has a constant velocity and is therefore in equilibrium because the tension in the string, which is pulling up on the object, is equal to the weight force , mg ("m" is mass, "g" is the acceleration caused by the gravity of Earth ), which is pulling down on the object. ∑ F → = T → + m g → = 0 {\displaystyle \sum {\vec {F}}={\vec {T}}+m{\vec {g}}=0} A system has

1343-837: A tributary of the Rock River resulting in one of the largest fish kills in Illinois history. As a result of an accident in Cherry Valley, Illinois , in 2009, the Association of American Railroads studied several options for increasing the crashworthiness of DOT-111 tank car designs and published new construction standards in a Casualty Prevention Circular, with the intent to revise the AAR Manual for Standards and Recommended Practices for tank cars that are used to transport ethanol and crude oil. Beginning on October 1, 2011,

1422-455: Is at the A end, and if there are six rings, ring-6 is at the B end. The tank rings can be welded in a "straight barrel" configuration, or with a "slope bottom" sloping down to a bottom outlet valve at the center of the tank."> A 2013 Senate of Canada committee report proposed mandatory minimum insurance for rail companies and recommended the creation of an online database with information on spills and other incidents from rail cars. Currently

1501-604: Is available through the Canadian General Standards Board. Approximately 230,000 litres (61,000 US gallons; 51,000 imperial gallons) of sulphuric acid was released, causing environmental damage, on 21 January 1995 near Gouin, Quebec. The 11 rail cars that released product were standard series CTC-111A tank cars. The derailment was caused by gauge loss, and the number of defective ties north of the derailment area likely exceeded Canadian National's (CN) maintenance standard. Transport Canada determined that

1580-478: Is much safer than the links before it. Janney coupler is like two curved human hand. With gooseneck couplers or offset shank couplers , the horizontal centerline of the coupler head is above the horizontal centerline of the coupler shank, or shaft, and the draw gear . This arrangement is designed for use with low-floor freight cars , to lift the coupler head high enough to match the couplers on other rolling stock. The large bogie boxvans for car parts , used on

1659-1449: Is no requirement to retrofit, repurpose, or retire existing DOT-111A cars built to the older design. The NTSB has called that design "inadequate," noting the older cars are "subject to damage and catastrophic loss of hazardous materials." In May 2015, the Federal Railroad Administration and Transport Canada jointly announced the new DOT-117 specification to supersede the DOT-111 design for all flammable class products, of which all examples would be required to be retired or rebuilt by May 2025. [REDACTED]  This article incorporates public domain material from Unclassified Safety Recommendation R-12-005-008, March 2, 2012 (PDF) . National Transportation Safety Board . [REDACTED]  This article incorporates public domain material from DOT-111 Tank Car Design (PDF) . National Transportation Safety Board . [REDACTED]  This article incorporates public domain material from Derailment of CN Freight Train U70691-18 With Subsequent Hazardous Materials Release and Fire; Cherry Valley, Illinois; June 19, 2009 (PDF) . National Transportation Safety Board . Janney coupler Knuckle couplers are

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1738-465: Is the force constant per unit length [units force per area], σ ( x ) {\displaystyle \sigma (x)} is the ...., τ ( x ) {\displaystyle \tau (x)} is the ...., and ω 2 {\displaystyle \omega ^{2}} are the eigenvalues for resonances of transverse displacement ρ ( x ) {\displaystyle \rho (x)} on

1817-458: Is the pulling or stretching force transmitted axially along an object such as a string, rope, chain, rod, truss member, or other object, so as to stretch or pull apart the object. In terms of force, it is the opposite of compression . Tension might also be described as the action-reaction pair of forces acting at each end of an object. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with

1896-660: Is withdrawn manually by a worker using the "cut lever", which is operated from either side of the railroad car and does not require the person to go between the cars. The only time the worker has to go between cars is after they have been securely coupled, to hook up the air lines for the pneumatic brakes , and the head-end power cables in the case of passenger cars . Modern Janney couplers typically mount to rail cars and locomotives via draw gear ; early Janney couplers often had transitional shanks which mounted into legacy link and pin coupler pockets, or bolted directly to steam locomotive headstocks . Knuckle couplers are used in

1975-577: The Bakken formation fields that contain volatile and/or corrosive chemicals, such as may issue from the hydraulic fracturing process. Crude oil is classed as Class 3 Flammable Liquid . The US regulator had ignored until 8 August 2013 the corrosive contents of Bakken formation crude oil. Hydrogen sulfide (H 2 S, sour gas ), a gas which is toxic to humans and flammable, has been detected as well in Bakken crude by Enbridge . The academic community commented in 2011 that increased concentration of H 2 S

2054-521: The Bakken formation was quickly released and caught fire. The ensuing blaze and explosions left 47 people dead. A November 2013 derailment near Aliceville , in Pickens County, Alabama involved a similar explosion of North Dakota crude oil. The Genesee & Wyoming company was the carrier for this 90-car train, of which 20 derailed and exploded. The train originated in Amory, Mississippi and

2133-662: The Railway Safety Act was empanelled by the Minister in February 2007. The review, which was tabled in Parliament later that year, has a different take on the subject. During a number of accident investigations over a period of years, the U.S. National Transportation Safety Board has noted that DOT-111 tank cars have a high incidence of tank failures during accidents. Previous NTSB investigations that identified

2212-789: The Victorian Railways , were fitted with gooseneck couplers for that reason. The Henricot coupler, a variation on the Janney coupler, was introduced by Belgian engineer and entrepreneur Émile Henricot  [ fr ] of Court-Saint-Étienne . It is used on certain electric multiple units of the Belgian State Railways , including the NMBS/SNCB class 75. Janney was a dry goods clerk and former Confederate Army officer from Alexandria, Virginia , who used his lunch hours to whittle from wood an alternative to

2291-632: The link and pin coupler. The term Buckeye comes from the nickname of the US state of Ohio , the "Buckeye state" and the Ohio Brass Company which originally marketed the coupling. In 1893, satisfied that an automatic coupler could meet the demands of commercial railroad operations and, at the same time, be manipulated safely, the US Congress passed the Safety Appliance Act . Its success in promoting switch-yard safety

2370-485: The "Sharon Coupler" PAT APP Nov. 10, 1910, 1911,1913, 1914, the "Simplex Coupler" PAT APP May 3, 1903, the "Climax Coupler", the "Latrobe Coupler", the "Tower Coupler", the "Major Coupler", the " Gould Coupler ", the "Pitt Coupler", the "R.E. Janney Coupler", the "Kelso Coupler" and others. A.J. Bazeley related railway inventions, U.S. patents and railway coupler mechanical drawings and illustrations filed and assigned to National Malleable Castings Company can be referenced by

2449-697: The "Type D", and was marketed by the Amsted Corporation, parent of ASF, as the "Standard for the World". It is still the most-used knuckle coupler in the world. The modern Alliance coupler still uses the modern AAR-10 or 10A contour, but has a shorter thus weaker head length, and thus cannot be used on North American interchanged rolling stock. Manufacturers of modern "Type E", "Type F Interlock" and "Type H Tightlock" couplers include McConway & Torley , ASF , and Buckeye, also known as Columbus Castings . The external contour of Janney knuckle couplers

DOT-111 tank car - Misplaced Pages Continue

2528-490: The 1932 contour, though tolerances, metallurgy and machining techniques have improved, resulting in notable reductions in coupler slack. Type H tightlock couplings used on passenger stock have a variation of the 10A contour that nearly eliminates slack during normal operation and minimizes the possibility of " telescoping " during a derailment. The purpose of couplers is to join rail cars and locomotives to each other so they all are securely linked together. Major Eli Janney ,

2607-560: The Americas, Africa, Asia-Pacific, UK, Belgium and Spain (narrow gauge railway only). Among its features: Janney Type E double-shelf couplers are yet another variety, typical on North American hazardous material tank cars . The Janney coupler is commonly used on railway couplings, as it is strong and locks automatically. Janney coupler was patented by Eli Janney after the US Civil War . The Janney interlocking coupling system

2686-541: The Chicago Malleable Iron which was founded in 1873 by Alfred A. Pope and John C. Coonley, who operated similar companies in Ohio and Indiana. By the late 1880s, the company employed nearly 1,000 men at its 26th and Western Chicago works, which manufactured various railroad couplers and steel products for the railroad industries. In 1891, Chicago Malleable became part of the new National Malleable Castings Co.,

2765-646: The Cleveland-based company, where Arthur J. Bazeley was employed as a senior design engineer, had additional manufacturing plants across the Midwest. National Malleable purchased the Latrobe Steel & Coupler's plant in Melrose Park, Illinois , in 1909. In 1923, when it had begun to supply the automobile industry, the company changed its name to National Malleable & Steel Castings. Its stock

2844-495: The DOT-111 tank "cars are not considered to provide the same degree of derailment protection against loss of product as the classification 112 and 114 cars, designed to carry flammable gases." A report on "The State of Rail Safety in Canada" was commissioned by Transport Canada in 2007. The report contains a 10-year statistical examination of its subject. Section 6 is entitled "Accidents involving dangerous goods". A formal review of

2923-756: The DOT-111 tank cars (which were already in 2012 acknowledged by the US NTSB regulator to be deficient for these purposes) to be loaded on the Lac-Mégantic train. The Lac-Mégantic runaway train had earlier passed through Toronto on its way from the Bakken fields of Dakota. A Canadian National employee said that roughly 10% of shipments through Toronto contain hazardous materials that are often stored on DOT-111 tank cars, but that only first responders have access to HAZMAT shipment information. Thirteen DOT-111 tank cars lost about 324,000 US gallons (1,230,000 L; 270,000 imp gal) of ethanol contaminating

3002-498: The Knuckle (the little flap that actually links two knuckles together, one of the few moving parts) with one that has a cut out in the middle of it and a hole bored through it; this modification was designed to work with the older Link and Pin couplers in widespread use before, though could reasonably work with European style chain couplers too. AAR: AAR, the modern American knuckle, they have several variants of their own; ranging from

3081-668: The M.C.B. The two couplers accepted were the Malleable Castings Company Bazeley Coupler , and the American Steel Foundries No.3 modified Alliance Coupler, out of nine couplers submitted to the committee as embodying the joint specification of design, The TYPE D coupler design based on The National Malleable Castings Bazeley Coupler patented designs and improvements was selected as the standard M.C.B Association's standard from 1918., after M.C.B. performance tested it along with

3160-517: The MCB was renamed as the AAR. Knuckle couplers of the 1880s and 1890s had a chaotic mixture of proprietary internal components, but all had the standard MCB external contour, making them compatible. There was a multitude of makes and models — Burns, Climax, Gould, Miller, Sharon and Tower. Some worked better than others. In 1913, American Steel Foundries (ASF) developed the Janney "Type D" coupler, that

3239-624: The Type C designs. The Type “D” Experimental Standard M.C.B. Coupler was unanimously recommended by the Master Car Builders Association and its Coupler Committee for adoption as the National/International (United States/Canadian) standard for coupler design and manufacturing specification uniformity by the M.C.B. Master Car Builders’ Association on June 15, 1916 after its 1915 Convention. This resulted in

DOT-111 tank car - Misplaced Pages Continue

3318-635: The U.S. Hydraulic fracturing of new wells in the shale oil fields in the interior of North America has rapidly increased use of DOT-111 cars to transport crude oil to existing refineries along the coasts. The Montreal, Maine and Atlantic Railway runaway train in the Lac-Mégantic derailment of July 2013 was made up of 72 of these cars, 63 of which derailed. Almost all of these derailed tank cars were damaged, and many had large breaches. About six million litres (1,600,000 US gal; 1,300,000 imp gal) of light crude oil originating from

3397-513: The UK) or Centre Buffer Couplers . There are many variations of knuckle coupler in use today, and even more from the past, some variants of knuckle include: Janney: the American original, a rather finicky coupler; reportedly annoying to make open and close. Castle: an improvement on the Janney design, and a step towards the modern knuckle. Split Knuckle: a rarer type, which replaces the finger of

3476-451: The UK, several versions of Janney couplers are fitted to a limited number of coaches, multiple units, wagons and locomotives. Janney Type E, Type F Interlock, and Type H tightlock couplings are compatible subtypes, each intended for specific rail car types. Prior to the formation of the Association of American Railroads (AAR) these were known as Master Car Builder (MCB) couplers. In 1934,

3555-443: The coupler and its moving parts. In order to govern uniform standards for the interchangeability and the proper relation between fitting parts, the A.R.A. Committee on Couplers and draft gears designed and distributed templates, gauges, and master guides to assure the proper interchangeability and fitting of parts to maintain the proper operation of various multi-source manufactured railway couplers. Tension (physics) Tension

3634-506: The current 60 per cent. The number of crude oil carloads hauled by U.S. railroads surged from 10,840 in 2009 to a projected 400,000 in 2013. In the third quarter of 2013, crude-by-rail shipments rose 44 percent from the previous year to 93,312 carloads, equivalent to about 740,000 barrels per day or almost one tenth of U.S. production. That was down 14 percent from the second quarter of 2013 due to narrower oil spreads that made costlier rail shipments less economic. On 7 January 2014, 17 cars of

3713-470: The derailment of a unit train of DOT-111 tank cars loaded with ethanol in Arcadia, Ohio , which released about 786,000 US gallons (2,980,000 L; 654,000 imp gal) of product. The Transportation Safety Board of Canada also noted that this car's design was flawed resulting in a "high incidence of tank integrity failure" during accidents. The Transportation Safety Board of Canada (TSBC) investigated

3792-430: The ends of the cars are designated "A" and "B." The B end of the car is the end equipped with the wheel or lever used to manually set the car's hand brakes . The end without the hand brake is the A end. As trains are assembled, either end of a tank car may be placed in the front or rear position. The tank shells are constructed of several rings welded together, with six rings in a typical configuration. By convention, ring-1

3871-409: The ends of the string. By Newton's third law , these are the same forces exerted on the ends of the string by the objects to which the ends are attached. If the string curves around one or more pulleys, it will still have constant tension along its length in the idealized situation that the pulleys are massless and frictionless . A vibrating string vibrates with a set of frequencies that depend on

3950-475: The evolving heavier demands by US railways, as well as, National Malleable Castings' international customers in the United Kingdom, India, and many other countries building and expanding their railway systems. A.J. Bazeley was directly responsible for over 90 registered U.S. patents for railway automatic coupler improvements through design, under the coupler type names which included the "Buckeye coupler",

4029-435: The fillet weld attaching the body bolster pad to the tank shell. Fillet welds at the interior and exterior sides of the head brace attach the head brace to the front sill pad, and an exterior fillet weld attaches the head brace to the draft sill. To the rear of the head brace, the draft sill is welded to the front sill pad, body bolster pad, and reinforcing bars. Because rail cars have no front or rear, for descriptive purposes,

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4108-432: The force per cross-sectional area rather than the force alone, so stress = axial force / cross sectional area is more useful for engineering purposes than tension. Stress is a 3x3 matrix called a tensor , and the σ 11 {\displaystyle \sigma _{11}} element of the stress tensor is tensile force per area, or compression force per area, denoted as a negative number for this element, if

4187-467: The length of a train. The draft sills are attached to steel pads that are attached to the tank. If the cars do not incorporate a continuous center sill extending the entire length of the car, the two draft sills at each end are referred to as stub sills, and the tank carries draft forces between couplers. In this case, reinforcing bars may be extended underneath the tank between the draft sills. Body bolsters and their associated body bolster pads centered above

4266-462: The new AAR standard for DOT-111 tank cars requires tank heads and shells to be constructed of thicker steel. The new specification also requires that heads and shells be constructed of normalized steel , and in all cases 1 ⁄ 2 -inch (12.7 mm) thick half head shields must be provided. The AAR has also mandated a more robust housing or rollover skid for protection of top fittings. The new standards only apply to newly manufactured cars; there

4345-423: The number of railroad employees steadily increased during that decade. When the Janney coupling was chosen to be the American standard, there were 8,000 patented alternatives to choose from. The only significant disadvantage of using the AAR (Janney) design is that sometimes the drawheads need to be manually aligned. During the transition period from link-and-pin couplers, knuckle couplers on many locomotives had

4424-670: The poor performance of DOT-111 tank cars in collisions include a May 1991 safety study as well as NTSB investigations of a June 30, 1992, derailment in Superior, Wisconsin ; a February 9, 2003, derailment in Tamaroa, Illinois ; and an October 20, 2006, derailment of an ethanol unit train in New Brighton, Pennsylvania . In addition, on February 6, 2011, the Federal Railroad Administration (FRA) investigated

4503-407: The process by which designs and repairs are presented, weighed, and evaluated, and, (2) railroad tank car design criteria, including whether head shields should be installed on all tank cars that carry hazardous materials." It is entitled "Ensuring Railroad Tank Car Safety" and available as ISBN   0-309-05518-0 . As mentioned above, derailment of a train containing Bakken crude oil derailed in

4582-422: The railcar trucks support the tank and protect it against lateral forces. The draft sill center plate serves as the attachment point between the tank car body and the truck assembly. (See schematic cutaway at right.) The body bolster pads and front sill pads are attached to the tank with fillet welds . At the rear edge of the front sill pad, a butt weld attaches the front sill pad to the body bolster pad and to

4661-661: The railway industry lags the pipeline industry in value of mandatory insurance coverage, to a ratio of 1:40. Railway operators are not required to inform Canadian municipalities about dangerous goods in transit. DOT-112 tank cars and DOT-114 tank cars have been required since 1979 under Regulation SOR/79-101 of the Canada Transportation Act for the transportation of gases such as propane , butane , or vinyl chloride . Transportation Safety Board of Canada Railway Investigation Report R94T0029 section 1.13.1 documents DOT-112 tank car and DOT-114 tank car standards:

4740-416: The rod is being compressed rather than elongated. Thus, one can obtain a scalar analogous to tension by taking the trace of the stress tensor. A system is in equilibrium when the sum of all forces is zero. ∑ F → = 0 {\displaystyle \sum {\vec {F}}=0} For example, consider a system consisting of an object that is being lowered vertically by

4819-573: The sharing of U.S. Patent improvements and agreed to by The National Malleable Castings Company, Henry Pope President; The Buckeye Steel Castings Company, The Gould Coupler Company , American Steel Foundries and The Monarch Steel Castings Company, and to be the active standard M.C.B. D Type forward from January 1, 1918. Buckeye Steel Castings Company was founded in 1881 as the Murray-Hayden Foundry before changing to The Buckeye Automatic Car Coupler Company and in 2002 after filing bankruptcy

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4898-495: The standard knuckle, to long drawbar ones, to passenger models, to a type designed specifically for tank cars. Janney couplers were first patented in 1873 by Eli H. Janney ( U.S. patent 138,405 ). Andrew Jackson Beard was amongst various inventors that made a multitude of improvements to the knuckle coupler; Beard's patents were U.S. patent 594,059 granted 23 November 1897, which then sold for approximately $ 50,000, and U.S. patent 624,901 granted 16 May 1899. In

4977-408: The string's tension. These frequencies can be derived from Newton's laws of motion . Each microscopic segment of the string pulls on and is pulled upon by its neighboring segments, with a force equal to the tension at that position along the string. If the string has curvature, then the two pulls on a segment by its two neighbors will not add to zero, and there will be a net force on that segment of

5056-409: The string, with solutions that include the various harmonics on a stringed instrument . Tension is also used to describe the force exerted by the ends of a three-dimensional, continuous material such as a rod or truss member. In this context, tension is analogous to negative pressure . A rod under tension elongates . The amount of elongation and the load that will cause failure both depend on

5135-758: The string, causing an acceleration. This net force is a restoring force , and the motion of the string can include transverse waves that solve the equation central to Sturm–Liouville theory : − d d x [ τ ( x ) d ρ ( x ) d x ] + v ( x ) ρ ( x ) = ω 2 σ ( x ) ρ ( x ) {\displaystyle -{\frac {\mathrm {d} }{\mathrm {d} x}}{\bigg [}\tau (x){\frac {\mathrm {d} \rho (x)}{\mathrm {d} x}}{\bigg ]}+v(x)\rho (x)=\omega ^{2}\sigma (x)\rho (x)} where v ( x ) {\displaystyle v(x)}

5214-619: The tank cars sustained multiple punctures and released their products. The products ignited and a large fire engulfed the derailed cars. The United States National Research Council was commissioned via the US Hazardous Materials Transportation Uniform Safety Act (1990) by the Federal Railroad Administration to write an impartial report on "(1) the railroad tank car design process, including specifications development, design approval, repair process approval, repair accountability, and

5293-411: The town of Lac-Mégantic , leading to a fire and explosion that led to many deaths and destruction of buildings. One issue raised by the Lac-Mégantic derailment, and substantiated by Enbridge complaints to the US regulator, is that Bakken crude oil is associated with a notable volatility. The US Federal Railroad Administration moved on 8 August 2013 to tighten standards for shipments of crude oil from

5372-493: The town to be evacuated. The BNSF train was 106 cars and 1.6 km long, of which at least 10 car were destroyed. Reports were that another train carrying grain and running to the opposite direction derailed first, causing the adjacent train with tank cars carrying oil from the Bakken formation to derail one minute later. Three days later, the US DOT PHMSA wrote that "Recent derailments and resulting fires indicate that

5451-528: The transported product when involved in accidents) are available." The TSBC instituted "Amendment Schedule No. 21 to the Transportation of Dangerous Goods Regulations", which mandated "the use of revised tank car standard CAN/CGSB 43.147-94. This standard restricts the use of 111A tank cars, and removes over 80 dangerous goods previously authorized for transportation in Class 111 cars." The updated standard

5530-676: The type of crude oil being transported from the Bakken region may be more flammable than traditional heavy crude oil... Based on preliminary inspections conducted after recent derailments in North Dakota, Alabama and Lac-Megantic, Quebec, involving Bakken crude oil [we mandate crude producers and shippers to] sufficiently degasify hazardous materials prior to and during transportation." The oil regulator for North Dakota stated in early December 2013 that he expected as much as 90 per cent of that state's oil would be carried by train in 2014, up from

5609-533: The use of Class 111A tank cars. An investigative report published 3 August 2013 by the Brandon Sun listed 10 railway derailments in the area over the past decade. Derailments caused no injuries over that period. On 2 May 2002, a train collided with a transport truck at the Firdale, Manitoba CN crossing. The derailed equipment included five tank cars carrying dangerous goods. During the derailment, four of

5688-541: Was born in Bristol, England , in 1872, and worked for the Great Western Railway until the age of 34 when he immigrated to Cleveland, Ohio , in 1906, where he worked as a mechanical engineer for National Malleable Castings, Co., inventing and designing improvements in the function, strength, and durability of the (MCB/ARA/AAR/APTA) Janney, Knuckle, Alliance couplers and other coupling devices/ draw gear for

5767-517: Was listed on the New York Stock Exchange beginning in 1936 The National Malleable Castings Bazeley Coupler 1905-1918 M.C.B. D Type as Universal M.C.B. Standard Adopted 1915 At a joint M.C.B. Coupler Committee meeting on July 15, 1913, out of numerous studied competing railway coupler manufacturers and designs two couplers were selected for the new proposed universal U.S./Canadian coupler design standard, adopted, June 15, 1916 by

5846-512: Was observed in the field and presented challenges such as "health and environmental risks, corrosion of wellbore, added expense with regard to materials handling and pipeline equipment, and additional refinement requirements". Holubnyak et al. write, further, that Bakken crude "may become soured through current oil field practices". At issue in the Lac-Mégantic derailment, then, is whether World Fuel Services and other defendants ought to have been aware of this two-year-old research when they ordered

5925-606: Was reformed as Columbus Castings. Railway couplers were manufactured in accordance with the Standard Specifications of the AAR covering the purchase and acceptance of couplers, knuckles, locks and other working parts as shown in their "Mechanical Division Manual of Standards and Recommended Practice". Specifications as of March 1939 required that the fabrication casting material be of open hearth or electric furnace grade "B" steel with specific metallurgic requirements to insure proper tensile strength and reliability of

6004-638: Was scheduled for a pipeline terminal in Walnut Hill, Florida that is owned by Genesis Energy . The final destination for the shipment was to have been the Shell Oil refinery in Mobile, Alabama . The accident happened in a depopulated wetlands area. Three cars experienced a boiling liquid expanding vapor explosion . On 30 December 2013, a similar explosion occurred in Casselton, North Dakota causing

6083-458: Was stunning. Between 1877 and 1887, approximately 38% of all railworker accidents involved coupling. That percentage fell as the railroads began to replace link and pin couplers with automatic couplers. By 1902, only two years after the SAA's effective date, coupling accidents constituted only 4% of all employee accidents. Coupler-related accidents dropped from 11,710 in 1893 to 2,256 in 1902, even though

6162-639: Was the first aspect to be standardized by the MCB in the 1880s. Prior to this, there was a chaotic variety of constantly evolving and proprietary external contours and internal components. In 1893, manufacturers standardized on the MCB-5 or Type C contour, then in 1915 on the improved MCB-10 or Type D contour, and again in 1932 on the AAR-10A or Type E contour. The 1893, 1915, and 1932 contours are measurably different with slight dimensional changes that improved performance, yet remain compatible. Janney couplers still use

6241-514: Was then made the MCB standard coupler for North America; new and rebuilt rolling stock had to be fitted with that coupler. That ended the market for knuckle couplers with proprietary components, excepting those exported from the US to other countries not complying with MCB standards. The Alliance coupler, named after the ASF-owned foundry in Alliance, Ohio , was developed as a lighter build than

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