Compressed gas trailers

Specialty Gases. The specialty gases are generally more reactive than the bulk gases and usually have low volume flow requirements in their appHcations. Historically, these have been deHvered almost exclusively in standard compressed gas cylinders. However, as the need for increased quantities has arisen, bulk specialty gas supply systems utilising larger ton-sized containers and tube trailers are being developed. 

Storage and Shipment. VDF or HFC-1132a is stored and shipped in gas cylinders or high pressure tube trailers without polymerization inhibitor and is placarded as flammable compressed gas. Terpenes or quinones can be added to inhibit polymerization. Elf Atochem North America, Inc. and Ausimont USA, Inc. supply VDE in the United States other producers are in Japan and Europe. 

For distributing larger quantities of gaseous helium, argon, and occasionally neon, a number of large, horizontal, compressed gas cylinders are manifolded on tmck semitrailers (called tube trailers) or railroad cars. Like individual cylinders, these serve both as transport containers and rental storage containers. Capacities of tube trailers range from about 300 to 5,000 m (10,000—175,000 fT) of gas. 

Seamless steel pressure vessels are the most common method in use today for hydrogen transportation at short distances (<200 km) and when small quantities are involved (up to about 500 kg). The different vessel options include cylinders, manifolded cylinder pallets and tube trailers. While single cylinders or manifolded pallets are trucked to the destination and off loaded, tube trailers, which consist of several steel cylinders mounted to a protective framework, are often left in place and replaced when empty. Transporting hydrogen in liquefied form is seven times more efficient in terms of actual hydrogen weight transported than using compressed gas cylinders. 

Tube-trailer (compressed gas) CHT, UH, ES 0.5-2.0 Cost increases more than linearly with distance... 

Transporting compressed gas on the road is state of the art. Compressed gas is shipped either in cylinder trailers or tube trailers (fewer, but bigger single vessels). More and more metal vessels are replaced by others made entirely or partly of composite materials in order to improve the ratio between dead weight and payload somewhat, which is particularly unfavourable for hydrogen. 

Nitrogen trifluoride gas is shipped as a compressed gas in steel cylinders and can also be provided by tube trailer. Metals suitable for use in NF3 systems at ambient temperatures are stainless steel, steel, brass, aluminium, copper, and nickel. Corrosion rates of less than 0.0025 mm/a at about 70°C have been measured for these materials [1,2]. However, the corrosion rate increases significantly in the presence of moisture or HF [2]. Fluorinated polymers such as Teflon, Kel-F, and Viton are not attacked by NF3 at ambient [1,2] and elevated temperatures [3]. These materials are recommended for flexible lines and fittings [1]. At elevated temperatures, where the reactivity is similar to that of fluorine, nickel and Monel are recommended as suitable materials for handling NF3 [1]. 

Cargo tank capacities range up to 17 000 gal (64 m ). Although no minimum capacity is given for them in the specifications, cargo tanks are normally large capacity tanks permanently mounted on truck bodies, or they form a semitrailer body. In some instances, truck tractors draw double tank trailers containing compressed gas. 

CGA G-l. 6, Recommended Practices for Mobile Acetylene Trailer Systems, 4 ed.. Compressed Gas Association, 1725 Jefferson Davis Highway, Arlington, VA 22202. 

Fluorine is authorized for shipment in cylinders as a compressed gas under DOT and TC regulations, and as a liquefied low temperature gas in liquid nitrogen refrigerated tanks mounted on truck trailers by special permit of the DOT [5, 8]. 

Nitrogen trifluoride is authorized for shipment as a nonflammable compressed gas in cylinders, including DOT/TC approved trailer tubes. Nitrogen trifluoride is normally compressed to 1450 psig (10 000 kPa) in cylinders. 

Silane is shipped as a compressed gas in cylinders and, in the United States, also in tube trailers under DOT exemption. 

At least one pressure relief device is required on any compressed gas cylinder or trailer tube offered for transport of oxygen. A pressure relief device must be selected in accordance with CGA S-1.1, Pressure Relief Device Standards—Part 1—Cylinders for Compressed Gases, [14]... 

The job of the CWS did not end with the production of flame throwers. Weapons had to be serviced, fuels had to be mixed with thickeners, and compressed gas or air had to be supplied. The CWS rigged up an air compressor and mixing vat carried on a truck or trailer. With this equipment troops could mix the hundreds of gallons of thickened fuel used by flame tanks, and compress the large volume of air needed as a propellant. ... 

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