REPORT OF SURVEY 1 Progress in Railway Mechanical Engineering, 1967-1968 Introduction the side post, and floor stringers are made of high density poly- urethane [3]. DEVELOPMENTS in the carbuilding field continued at a Pullman-Standard has developed an atmosphere control sys- brisk pace even though there was a sharp decline in the purchasing tem (Figs. 5 and 6) which will both refrigerate and control the of uew equipment by the railroad industry. The trend to pro- oxygen content of the environmental air in an insulated railroad duce specialized equipment designed to help the consignor and car. The Pullman-Standard system combines nitrogen storage Downloaded from http://asmedigitalcollection.asme.org/manufacturingscience/article-pdf/91/3/817/6499103/817_1.pdf by guest on 26 September 2021 consignee in the loading and unloading of a specific commodity tanks, spray headers, and temperature sensing, and control equip- continues to dominate the development of new equipment. As ment, which are standard components of Linde's "Polarstream" the users of the railroad's service continue to approach their system with Pullman-Standard's specified orifice, heat exchanger, physical distribution problems on a total cost basis, this trend air motor, and fan to achieve the desired temperature and atmo- toward specialized equipment can be expected to continue, and spheric condition within the lading area. The sj'stem operates perhaps accelerate, in the near future. by releasing liquid nitrogen into the lading area. The nitrogen instantly vaporizes and absorbs heat in the lading air space. The orifice draws in outside air to maintain the desired oxygen New Freight Cars percentages in the lading area. By increasing the oxygen content Several new freight cars designed to facilitate the handling of a of the car, discoloration of the meat while in transit can be pre- specific commodity were introduced. Pullman-Standard, the vented. Canadian National Railways, and the Chicago, Burlington, and The Santa Fe, Burlington, and Great Northern railroads have Quincy Railroad have all introduced foam insulated freight cars placed in service a high-cube, canopied, depressed center flatcar designed to facilitate the handling of commodities requiring a to carry cockpit and nose assemblies for Boeing's huge 747 jet specific temperature while in transit. The Pullman-Stanclard- airplanes (Fig. 7). The freight car, which is termed "the world's built, 60-ft, insulated boxcar (Fig. 1) uses foamed-in-place largest freight car," with a capacity of 10,700 cu ft, was polyurethane insulation. The polyurethane insulation is es- manufactured by the St. Paul Foundry and Manufacturing Com- sentially a 5-in. blanket capable of holding a specific temperature pany. The car, fitted with special interior holding devices de- within specified limits for seven days [l].2 signed specifically for Boeing 747 nose assemblies, measures 61 ft The Canadian National's version of a foam-insulated refrigera- 8 in. in length, 19 ft 2 in. in height above the rails, and has a tor car (Fig. 2) also uses foamed-in-place polyurethane insulation breadth of 12 ft 10 in. [4], to envelop the car. Because the floor is predominantly sup- Greenville Steel Car has designed and built a flatcar to carry ported by the polyurethane insulation, the foam becomes part of hot steel coils of different sizes without bracing (Fig. 8). The the cars structural support system allowing the use of wood and 75,000-lb coil car basically consists of heavy sills supporting other heat loss material to be held to a minimum. The tempera- the trough between them. The all steel trough is designed to ture control system can maintain temperatures ranging from —10 accommodate coils ranging in diameter from 36 to 84 in. and with deg F to 70 deg F, no matter what the outside temperature. The temperatures up to 800 deg F [5], heat saving feature of the car will enable the car to operate long The Thrall Car Manufacturing Company introduced a bulk- distances without servicing even if a mechanical failure should oc- head center beam flatcar designed to handle commodities such cur en route. The car is so well insulated it may eliminate the as lumber, pipe, gypsum, steel, and containers (Fig. 9). The 100- need for refrigeration or heating units for many types of traffic [2], ton car features a deep above deck structure located on its longi- The foam-insulated car developed by the Burlington Railroad tudinal center line and extending full length between its 11-ft (Figs. 3 and 4) is a refrigerator car using liquid nitrogen as a cool- bulkheads. The deep beam section serves the same purpose as ant. The Polarstream process uses liquid nitrogen in carefully the below deck center sill in conventional cars, but permits a regulated amounts to both cool the car and induce a low oxygen reduction of 20,000 lbs on the cars light, weight. Because the atmosphere designed to impede product deterioration. Equip- 11-ft beam structure pitches inward from its broadest point at ment installed in the car's engine compartment includes a 1200- deck level, and since the deck itself is also pitched to form a 90-deg gallon 8100-lb capacity liquid nitrogen storage tank, a flow angle with the beam, the car has exceptional lateral load retention. regulator, and temperature control devices. Nitrogen is released In May 1965, a deep beam STRONGBACK® 70-ton bulkhead into the car through small perforated pipes attached to the center car was introduced by Transport Leasing. However, unlike meat rail running the full length of the car. The nitrogen supply the Thrall car's 11-ft beam, the Transport Leasing car's center will last from origin to destination mainly because the car has a beam rises only 2 ft 4 in. above the deck, and a portion of it low heat loss. The low heat loss is possible because 5 in. of is located below the deck [6]. polyurethane insulation enclose the car. Also there are 48 per- A new extra wide auto rack car for transporting automobiles cent fewer conductive parts in the walls, roof and floors because and trucks was developed by the Southern Railway and Paragon Bridge & Steel (Fig. 10). The 89-ft 4-in. standard level flat- cars are fitted with auto racks having a. breadth between curbing ' Chairman, N. E. Bateson; members, R. L. Lich and P. H. Baker. angles on their upper levels of 113 in.—a full 13 in. greater The survey covers the period September 1, 1967, to September 1, 1968. than that of earlier racks. The new rack gains the added 13 2 Numbers in brackets designate References at end of paper. in. of deck width by extending its curbing angles out to be- Contributed by the Railroad Division and presented at the yond the outer surfaces of the vertical side posts. By redesigning Winter Annual Meeting, New York, N. Y., December 1-5, 196S, of the column supports at the car's side sills, the width of the loading THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS. Manuscript re- area on the first level has been increased from 94 to 99 in. ceived at ASME Headquarters, September IS, 1968. Paper No. 68—WA/RR-9. In addition to the extra width, this new rack has each end of the Journal of Engineering for Industry Copyright © 1969 by ASME AUGUST 1 9 6 9 / 857 Downloaded from http://asmedigitalcollection.asme.org/manufacturingscience/article-pdf/91/3/817/6499103/817_1.pdf by guest on 26 September 2021 method of physical distribution. Although this car is similar in basic design to ACF's center flow dry bulk commodities car, this new car uses low-pressure air (5 psi versus 15 psi of previous models) to discharge its cargo into local delivery trucks or into a plant storage system. This low pressure differential car is lighter in weight and can belter accommodate a greater variety of bulk commodities such as flour and dry chemicals. Materials can be discharged by vacuum and gravity as well as by pressure [9]. A new composite steel and aluminum triple-hopper covered hopper car has been designed by Magor Railcar Division of Fruehauf Corporation (Fig. 13). The principle used in develop- ing this design has been to have an aluminum container mechani- cally fastened to a steel underframe. Additionally, the interior of the car has been improved by curving intersecting surfaces to prevent lading retention in corners and valleys. National Steel Car has built 120 covered ore cars to transport iron ore for the Canadian National and Ontario Northland rail- Fig. 2 ways (Fig. 14). These 100-ton ore cars have no center sills, trans- mitting draft and buffing forces through the tubular steel bodies. At the mine the cars are fed by gravity under loading silos where second deck hinged so that it may he raised to produce clearances "trip" levers operate the roof hatches, opening and closing them for automobiles being loaded or unloaded from the first level [7]. automatically. At destination the lading is dumped through During the year, several new railcars were introduced for the drop doors—six cars being unloaded in 60 sec [10]. efficient handling of bulk commodities. The Hawker Siddeley Several new concepts of tank car equipment were introduced Limited of Canada has designed a 100-ton open to]) hopper ear last year. Union Tank Car has developed and plans to produce specifically conceived to haul coal (Fig. 11). The "bathtub" 40 basic designs of a "Changeable" tank car which will have design is of stressed skin construction. The sides of the car flexibility and versatility to meet specific lessee requirements contain the load and function as an underframe and reduce over- (Figs.