Nature and Usage of Magnesium

Magnesium is one of the lightest structural metal so far known in the world. Besides its light-weight construction, a few of the other advantages it offers are: high specific strength and stiffness, excellent damping and cutting properties, and easy recycling. Magnesium alloy is internationally used in the automotive industry to remove weight, save energy, reduce pollution and improve the environment. Automotive fuel consumption per hundred kilometers will eventually be reduced to 3L in developed countries, and magnesium consumption in European automotive industry accounts for 14% of the total consumption of magnesium. It is expected to increase15-20% annually in the future, achieving 200,000 tons in 2005.

Compared with plastics, magnesium alloy comes with lighter weight and higher strength, also it has better vibration and thermal fatigue resistance, better thermal conductivity and electromagnetic shielding ability, and excellent casting process performance, especially it is unproblematic for recycling. Thus all these contribute to its replacement of steel, aluminum and plastic and becoming a new generation of high-performance organizational material. To meet the high integrating, lighter and smaller trend of electronics and telecommunications devices, magnesium alloy can be the ideal housing material for products concerning with traffic, electronic information, communications, computers, audio-visual equipment, hand tools, electrical machinery, forestry, textiles and nuclear power plant. Developed countries usually attach great importance to the development and application of magnesium alloy, especially its application in producing auto parts, laptop computers and other portable electronics. With the amazing trend of 20%’s annual growth rate, it indeed is developing compellingly.

Magnesium is a major component in aluminum alloys. The world’s yearly demand is about 15 million tons. China’s annual aluminum alloy output is 2.9 million tons in 2000, among which about 10,100 tons of magnesium are needed. With the increasing demand for high-strength and low-sulfur steel in auto industry, natural gas pipelines, offshore drilling platforms, and bridges, buildings constructions during recent years, many Chinese steel mills have started producing high-quality steel using magnesium powder to achieve deep desulfurization. Magnesium powder has a rather promising market for steel desulfurization. In addition, it can also be applied in manufacturing chemical products, medicines, fireworks, signal flares, metallic reducing agents, paint, welding wire and agents for nodular cast iron.

Magnesium powder is the powder form of elemental magnesium. It is soluble in mineral acids, concentrated hydrofluoric acid, ammonium salt and hot water. Mainly magnesium powder can be prepared by the electrolysis of molten magnesium chloride and dehydrated carnallite. Magnesium powder can be very explosive and it contributes high temperature and dazzling white light when it burns. This is also why magnesium has a wide range of uses in the military and aerospace industry. For example, working as the rocket ramjet and removal of propellant gas. Besides that, magnesium powder can also be used as cleaning and reducing agents in the steel industry and non-ferrous metal casting, while the reducing agent for rare metal production. In the chemical industry, magnesium powder is becoming more and more popular as it can be used for spraying, coating, and anti-corrosion. It can also be very useful in monocrystalline silicon, polycrystalline silicon and metallurgy powder casting.

Modern warfares are demanding on military’s remote rapid deployment capacity, requiring the increasing use of light metals in handheld weapons, armored vehicles, trucks and aviation guided weapons. Weight reduction is the main move to improve the operational performance of weaponry. Therefore the lightweight characteristic of magnesium has determined aluminum alloy to be the indispensable structural material for spacecraft, military aircraft, missiles, high mobility vehicles and vessels. This also can illustrate the national defense needs of vigorous advance of magnesium alloy application scope.

Climb the Safe Way with PASMA Training

Advent of urbanization marked the beginning of high structures like mobile towers and bridging units. Working at such heights is as dangerous as exciting it sounds. Prefabricated Access Suppliers’ and Manufacturers’ Association (PASMA) brings to this industry training courses which equip and update individuals working in these areas. As a budding professional in this arena, you get to train and learn under subject matter experts who give you a larger perspective apart from the course curriculum. Read on to know more about PASMA training and its different aspects.

How Does PASMA Equip You?

One of the primary subjects of learning from this course is the best practices to be followed at heights. This is vital to guarantee your safety as a technician and boosts your comfort level on high towers which improves your productivity manifolds. Regulations regarding working at heights and discerning unsafe situations are a part of this training. Apart from this they also impart tips on safety equipments and right storage practices.

Teaching fall protection principles and equipping you for potential risks are among the important modules of these courses. Risks or hazards may come along due to a number of reasons like high speed irregular winds or falling objects. Presence of mind and knowing what to do next are two factors which are essential to save your life and protect you against crippling injuries. This is what PASMA does for you. It trains you to be productive and safe however high you are standing.

Benefits of PASMA Training

PASMA is a pre-requisite for most of the jobs in this arena. With this certificate along with IPAF training you get a free pass to apply and begin work with reputed companies in this segment. It proves your competency and potential to serve a firm in the best manner. Apart from this, with PASMA you are now knowledgeable to test the safety equipment used and understand the different requirements of your on-site profile. At this point you are ready to work as an operator or supervisor who is equipped to work the safe way.

Steady career progression is another key benefit that this training provides you. Once done with the training, there will be nothing that inhibits you or your firm from promoting you to more responsible roles. In-depth understanding of the subject makes you a perfect fit to be an employee in command. From operator to supervisor and then to manager, you will be able to glide through these phases hassle free.

Scope for Specialization Courses

PASMA brings to you a range of courses suited for different requirements like low-level access and towers. The courses contain theory and practical lessons which makes the learning more literal and close to real work. Most of these courses are completed in a day, which makes it convenient and easy to be planned for working individuals as well. You can choose to take the specialist training depending on your area of work.

The world is full of limitless opportunities; make the best use of them with the right set of trainings and qualifications. Stay updated with PASMA training and be sure to stay safe on higher planes.

Rolling Stock of the New York City Subway System

Subway Cars:

Subway cars are, in essence, the heart of any underground rapid transit system on rails and numerous types have served the New York network during its more than a century of operation.

The IND’s R-1s, for instance, ushered in a new designation scheme for the unified system. Initiated by the Board of Transportation and maintained by the Metropolitan Transit Authority (MTA), it employed an “R” prefix to denote revenue control combined with the number of the contract awarded to the subway car manufacturer. Consecutive numbers indicated successive contracts for identical or virtually identical coaches, which sometimes featured minor modifications, while a letter suffix, such as “A,” usually denoted an upgrade.

As the basic design for the IND’s fleet throughout the 1930s, the R-1 was succeeded by contracts R-4, -6, -7, and -9, which resulted in a 1,703-car production run.

The R-10, also for the IND, represented the first post-war and therefore new-generation type. Built by the American Car and Foundry Company between 1948 and 1949, it offered several advanced features, including all-welded construction; a single, 100-hp traction motor on each of four axles; both pneumatic and dynamic braking; a brake pipe pressure increase from 70 to 110 psi; and generators that served as brakes by reducing motor speed. A more rounded roof modified its external appearance, replacing the former, and sharper, clerestory one, while interior appointments included fluorescent lighting and smaller ceiling fans. Four hundred of these “SMEE”-or straight air motor electric-pneumatic emergency cars-were produced.

The R-12, dimensionally the IRT equivalent of the IND’s R-10s, incorporated the same propulsion, braking, ventilation, and window features in a 51-foot-long and 8.9-foot-wide (as measured at the door sill) car, but introduced double passenger doors, side seats (for 48 passengers), and poles to replace the former grab handles.

Manufactured by the American Car and Foundry Company, it became a welcomed sight when it appeared on the barge transporting it across the East River from the Hoboken Rail Terminal in 1948 because World War II-created material shortages had squeezed the last mile out of the coaches they replaced. The type was inaugurated into service on the IRT Flushing line.

Because of unsatisfactory performance, its predecessor R-11, constructed by the Budd Company in 1949, never preceded beyond the initial order for ten, although it had featured several innovations, including stainless steel bodies, modern interiors, germicidal lamps, public address systems, disc brakes, and electric door motors.

The IRT division’s fleet renewal needs were filled with several successive contracts whose cars were based upon the R-12. The R-15, for example, featured arched roofs, two portable windows in each passenger door, and leatherette longitudinal seats, and later sported maroon paint schemes with beige stripes.

Five years after car #6239 entered service, it was retrofitted with an air conditioning system, the first in the New York subway system to do so. But this apparently not ready for prime time novelty itself succumbed to the heat when it failed after only two weeks of operation.

The intermittent R-16, dimensionally conforming to the BMT and IND “B” division, was made by the American Car and Foundry Company between 1954 and 1955. Introducing a new body style, built up of steel sheets, it appeared in Pullman green colors with exposed screws, and sported rectangular-windowed passenger doors, fluorescent lights, recessed Axiflow ceiling fans, and public address systems.

Measuring 60 feet, like the IND cars, it was the heaviest at such a length, weighing 85,000 pounds and was used to inaugurate service to Rockaway Beach in 1956 on abandoned Long Island Railroad tracks.

The R-17, the “A” division counterpart, was manufactured by the St. Louis Car Company and the first of the 400 ordered were inaugurated into service in 1955 on the Pelham Bay-Lexington Avenue route.

Other than a few subtle style variations, the succeeding R-21s and -22s were identical to this standard.

The R-26, of which 210 were produced by the American Car and Foundry Company from 1959 to 1960, was the IRT equivalent of the articulated car, although it was operated in a “married pair” configuration in which neither was autonomous enough to run without the other. Even numbered ones, for instance, featured motor generators and batteries for low voltage power, while the odd numbered ones sported air compressors, main reservoirs, and brake equipment feed valves. Passengers were accommodated in molded fiberglass seats.

Three subsequent contracts, for 770 cars based upon this design, were awarded to the St. Louis Car Company and designated R-29s, -33s, and -36s, the first of which was deployed on the Broadway-Seventh Avenue local line.

The same company was also awarded the R-27, -30, and -30a contracts for 550 “B” division coaches, the first of which was delivered in 1960 and placed in service on the local Fourth Avenue and Brighton line route.

During the eight-year period from 1953, when New York State legislature created the New York City Transit Authority as a separate public corporation to operate all of the city-owned subway routes, and 1961, a prosperous period generated unprecedented rider demand, and the subway system itself embarked upon a substantial station improvement and fleet renewal program. The R-30s, along with R-27s and R-30as, replaced half of the BMT fleet at this time.

Operating as married pairs, the cars were able to share parts, thus offering both equipment and maintenance cost savings. Odd-numbered cars, for instance, were equipped with air compressors for their brakes, while even-numbered ones offered motor generators and batteries to power motorman controls. Retaining the dark green exteriors and blue and gray interior color schemes of the previous R-16s, the R-30s, as well as the R-27s and R-30as, sported plastic, lengthwise seating benches.

An historically important car was the R-33S. Nicknamed “bluebird,” it was a tri-door car painted with a unique powder blue and off-white livery and used on 11-car “World’s Fair Express” trains, shuttling more than 51 million passengers from Times Square to Flushing Meadow Park during the 1964-1965 event. Operated in a “married pair” configuration, it otherwise formed part of ten-car, or five-set, trains and most were later rebuilt in the Coney Island Overhaul Shop. The “S” in its designation indicated a single cab. All others had two, installed at either end.

Although these contracts enabled the “B” division to commence its modernization program, and the R-17, -21, -22, -26, -29, -33, and -36 series facilitated the “A” division’s own, the BMT itself had still been saddled with 600 of its original “A-B” Standards and all of its articulated D-types, while the IND continued to operate all of its 1930 designs. What followed, then, were the first next-generation cars.

Designated “Brightliners,” these 60-foot-long coaches were the first to introduce fluted stainless steel construction, replacing the previous conventional steel material, and represented the first contract (R-32) awarded to the Budd Company of Philadelphia. They featured several improvements, one of which almost became a hindrance. Although their lower gross weights-of 70,000 pounds versus the 80,000 of, say, an R-27-gave them sprightly performance, that very weight reduction exerted less pressure on their suspension systems and therefore decreased the clearances within the BMT route network.

Initial deployment saw operation on the line’s Sea Beach, West End, and Brighton routes.

A subcontract for the R-32a resulted in interior lighting modifications.

Nevertheless, both types enabled the BMT to complete its modernization program by 1965.

Refocusing its efforts on the IND side of the program, the Transit Authority ordered 200 R-38 cars in 1966 from the St. Louis Car Company, and these offered several innovations, including lower-body fluted siding; a single console for power controls, indication lights, and brake valves in the motorman’s cab; and an electrical load sensor, which adjusted their braking action based upon car weight, itself a function of passenger load. The type was placed in service on the “E” and “F” lines.

Although the subsequent R-40 “St. Louis Car” eliminated the boxy appearance characteristic of rapid transit rolling stock, it sacrificed practicality for aesthetics. Slightly curved sides and slanted ends, almost suggesting monorail lineage, precluded safe, inter-car passage during movement because of the excessive gaps between them, and end doors were consequently locked and supplemented with a tangle of side hardware, such as slanted grab irons, low handholds with and without pantograph gates, and high handholds.

Of the 400 cars produced by the St. Louis Car Company between 1967 and 1968, the last 100, designated R-40Ms, appeared with vertical ends, greatly increasing their subway application.

The follow-on R-42, of which another 400 were built, was identical and featured air conditioning systems from inception, others in the series requiring retrofits. The type saw service on all “B” division routes.

In order to reduce the net number of cars per train, along with their operational and maintenance costs, yet maintain overall passenger capacity, the Transit Authority ordered 352 coaches from the St. Louis Car Company under contract R-44, in effect introducing a third “B” division length of 75 feet after the 60 feet of the R-1s and the 67 feet of the “A-B” Standards. Fifty-two of these cars were operated by the Staten Island Rapid Transit System, which offers no inter-track connection with the New York City subway network.

Featuring four 115-hp motors and composition brake shoes to replace the formerly standard cast iron ones, the R-44 intermittently offered full-width cabs for the motorman and the conductor and re-introduced the mixed transverse and longitudinal seating configuration.

Equipment varied according to car type. “A” cars, for example, offered air compressors, main reservoirs, and low voltage equipment. “B” cars provided traction motors, control groups, air reservoirs, and brake controls.

Although the type achieved a subway car record of 87.75 mph when it was run on the 5.9-mile Long Island Railroad track from Woodside to Jamaica on January 31, 1972, its scheduled service, initially on the “A,” “D,” “E,” and “F” lines, revealed an excessive number of mechanical issues.

Pullman Standard was awarded the contract for its 75-foot-long complement, but its promise, despite a new design feature, quickly plummeted. The R-46, whose 750-strong order represented the largest single one in subway history, introduced a new truck with an air suspension system designed by Rockwell International to replace the quarter-century standard one made by General Steel Industries, but it ultimately developed cracks. Initial operations saw its deployment on the former IND Queens line.

The next round of subway car replacements, now targeted at the “A” division, signaled the next-generation of cars.

Because of the rapid and massive nature of the system’s 24-hour-per-day operation, the now-aging state of the IRT R-14s, -15s, -17s, -21s, and 22s wailed for replacement and funding provided by the Metropolitan Transit Authority’s five-year capital improvement plan facilitated acquisition of 1,150 of them, 325 of which were ordered from Kawasaki Heavy Industries of Japan under contract R-62 on April 12, 1982 and 825 of which were obtained from Bombardier of Quebec, Canada, under contract R-62A seven months later, on November 15. The later incorporated different types of motors and brakes.

Both incorporated heavyweight components for optimum longevity and minimum maintenance costs and a high degree of part interchangeability, but these 51-foot-long, 74,500-pound coaches also offered several innovations, including stainless steel construction with fiberglass end caps, multi-tone rubber flooring, heavy sound insulation, corner cabs, dual (power and brake) motorman handles, and contoured fiberglass seating.

The type entered service on the #4 line on May 7, 1984.

Its “B” division counterpart, constructed under contracts R-68 and -68A by, respectively, Westinghouse-Amrail and Kawasaki, were deployed on the “B,” “D,” and “G” lines and on the Franklin Shuttle.

21stCentury Rolling Stock and Routes:

The New York City subway system, by its very rapid transit nature, is not a static entity and can therefore only exist by creating the routes its riders need and purchasing the rolling stock to serve them.

Shortly before the 21stcentury dawned, it had turned its attention toward the latter by ordering two five-car R-110A sets from Kawasaki for “A” division routes and three three-car R-110B units from Bombardier for the “B” division network. Both were intended as new-technology prototypes.

Tested in order to provide performance and system evaluation, they featured welded steel construction, AC traction motors, battery power operation, air bag suspension, computerized traction and braking control, electronically controlled door motors, automatic announcements, automatic climate control, and electronic route and destination signage.

Most of these features were incorporated in the subsequently ordered R-142 (680 from Bombardier) and -142A (400 from Kawasaki) in 1997. With a 51-foot overall length and 8.9-foot width, the type offered a 70,000-pound empty weight and maximum, 62-mph design speeds.

Configurations of both varied. “A” cars, with a single cab and two motor trucks, offered seating for 34 and standing room for 148, while “B” units, devoid of cabs and equipped with a single motor truck, respectively accommodated 40 and 142.

Inaugurated into service on July 10, 2000 on the former IRT #6 line, the new Millennium R-142 cars replaced most of the earlier-generation R-26, -28, -29, -33, and -36 “Redbirds,” so nicknamed because of the red body and silver roof paint schemes they had sported.

The dimensionally comparable “B” division R-160A (400 ordered from Alstom of France) and -160B (260 from Kawasaki) were intended as R-32, -38, -40, -40M, and -42 replacements and were inaugurated into service on December 22, 2008 on the “E” line.

Although the New York City subway system’s foundation was laid when it became unified, its network, like the trains that ply its track, hardly remained stationary.

Both the Archer Avenue subway and the 63rdStreet tunnel opened between 1988 and 1989, for example, and the latter’s connection to the Queens Boulevard tracks was completed in 2001. Other projects included the South Ferry Terminal #1 line, the Fulton Street Transit Center, and the westward extension of the #7 line. But the most massive redimensioning of the system occurred when a significant gap in its coverage was definitively plugged with the Second Avenue subway line.

Thirteen years before the elevated tracks that had once plied the route had been razed in 1942, proposals to replace them with a subterranean passage had already been discussed and, with demolition of the Third Avenue el 14 years later, the service gap became more gaping than the excavations needed to plug it would have. Yet, while the plan behind it lapsed, its need only rose: East Side neighborhoods, once predominantly industrial, experienced their own metamorphosis, serving as a magnet for population redistributions as their profiles reflected decided commercial, corporate, and residential sides.

Microscopically, the very same conditions which had originally given rise to the subway system at the turn of the 20thcentury occurred in this pocket of Manhattan-namely, devoid of either elevated or underground lines, riders were forced to use the only remaining transportation artery-the streets, whose increasingly clogged conditions screamed of the need for an alternative before they were choked into motionless silence.

The closest subway lines, the IRT #4, 5, and 6 that ran below Lexington Avenue, were logistically too distant and, instead of serving as a rapid transit convenience, only became the opposite to those across town.

Although a second vision foresaw a dual-track routing from Lower Manhattan to the Bronx-and several tunnels facilitating it had already been dug-financial constraints during the 1970s served more of an obstacle to it than the rock through which its lines would have to be bored.

The idea, at least in theory, never fully died and, like a ten-car train, regained momentum at the end of the 20thcentury with the Manhattan East Side Alternatives (MESA) study of 1995, which determined that the existing #4 and 5 lines could not adequately meet the demand-and part of that demand stemmed from riders who lived or worked up to a half-mile from its stations.

One of the 20 proposed remedies was to continue to lay a Second Avenue subway line and it was selected, with ground broken for it on April 12, 2007. Running below its namesaked avenue from the Financial District to 125thStreet, the dual-track infrastructure provided West Side and Brooklyn access by means of a 63rdStreet tunnel link to existing tracks.

The four-phase construction project entailed an initial 96thto 63rdStreet line, itself an extension of the “Q” train, and then a westward, cross-town routing for an “F” line interchange at 63rdStreet itself. Following existing, but unused track below Central Park, it would resume its southerly direction beneath Seventh Avenue, crossing the Manhattan Bridge to Brooklyn.

After more than a century, the New York City subway system would ultimately be able to correct the inherent imbalance created by its West Side routing concentration.

Followed its own Track:

The New York subway system reshaped the city it served until it ultimately reshaped itself.

Currently divided into “A” division or former IRT numbered lines and “B” division or previous BMT and IND lettered lines, it is the world’s largest, 24-hour rapid transit system, with underground, elevated, ground-level, open-cut, and embankment routes, serving 468 stations via 842 duplicated revenue and non-revenue track miles plied by 6,282 cars, which, in 2011, collectively traveled 342.7 million miles and transported over 1.6 billion passengers.

More than anything, however, it ended up following its own track. Extending from its Manhattan heart, it pumped the population through it, like arteries, to its outer Brooklyn, Bronx, and Queens boroughs, creating a cohesive metropolis that operated as a single whole, until three decades after it had first put wheels on its rails, it turned around and unified itself-as the New York City subway system.