Container Designs

The NRC has developed special procedures for the handling, transportation, and storage of nuclear fuel because radioactivity can be a health hazard if not properly shielded. Spent fuel is typically transported by rail or tmck in heavily shielded (Type B), sealed, thick metal shipping containers designed to withstand possible accidents, such as derailments or coHisions, which may occur during transport. The NRC certifies that each shipping container meets federal requirements. The U.S. Department of Transportation sets the rules for transportation. 

The equipment in which the dust is handled or stored should be designed to contain the pressure resulting from an internal explosion. Most dusts show maximum pressures of ca 345—700 kPa (50—100 psi) however, the rate of pressure rise changes from ca 700 to 70,000 kPa/s (100—10,000 psi/s). Equipment-containment design can be coupled with explosive-venting design for the equipment and the building. 

Tanks that could be subjected to vacuum should be provided with vacuum-breaking valves or be designed for vacuum (external pressure). The ASME Pressure Vessel Code contains design procedures. 

FIG. 21-42 Typical flexihle-hiilk-container designs and loading- and iinload-ing-spoiit designs. (Courtesy of Bonar Co., Ltd. )... 

There is no available evidence that PBDs occur in FIBC operations and therefore no demonstrated need for thin walled Type B containers designed with a breakdown voltage of 4 kV or less [lOj. However, since Type B containers are commercially available and in principle may offer slightly less risk, they might be considered where thin walls will not have a detrimental effect on product quality (6-7.1.1). 

Use only labelled, insulated containers designed for cryogens, i.e. capable of withstanding rapid changes and extreme differences in temperature, and fill them slowly to minimize thermal shock. 

All rail tank cars must be equipped with roller bearing wheels. Using a container designed for the maximum pressure that the contents can generate from ambient conditions will eliminate the need for refrigeration of the container for safety. Overpackaging can be used to provide maximum protection for example, use DOT Specification 105 tank cars instead of general purpose cars. 

In addition to improving safety during transportation by optimizing the mode, route, physical conditions, and container design, the way the shipment is handled should be examined to see if safety can be improved. For example, one company tested to determine the speed required for the tines of the forklift trucks used at its terminal to penetrate its shipping containers. They installed governors on the forklift trucks to limit the speed below the speed required for penetration. They also specified blunt tine ends for the forklifts. 

Containment design details - basic structure, major contents (beat structures), internal safety systems performance data, special features, reactor cavity/sump details, layout elevations and floor plans, fnateriais specifications, design limits, etc. 

A number of steps can be taken to minimize dust generation and dispersion. For the clamshell case, an active containment design was pursued to minimize dispersion. Active containment relies upon an inflow of air into some type of enclosure. 

Procedures for assurance of quality in the design, fabrication, installation, maintenance, testing and inspection for critical equipment are ) red. Safety requires that critical safety devices must operate as i led and process system components must be maintained to be able to contain design pressures. 

NFPA 69 (1997) provides equations for calculating the required design pressures for both types of containment design. It also discusses the limitations of deflagration pressure containment design. 

More information about pressure containment design is available in NFPA 69 and the books by Bartknecht (1981, 1989) and Eckhoff (1997). 

There are several areas to consider when discussing the future of the food can. Anti-pollution legislation, new can-making technologies, and public safety aspects will have a pronounced effect on food container design. 

On occasion the polyethylene has been blamed for odors caused by other parts of the container design such as screw cap liners, printing inks on the bottle exterior, adhesives used to laminate polyethylene to paper, and the fiberboard or the lining of material used in the separate exterior overpack in which a polyethylene container is held. Careful selection of all of these related materials is always advisable with liquid food products. 

Molecular Containers Design Approaches and Applications D. R. Turner A. Pastor M. Alajarin J. W. Steed... 

Turner DR, Pastor A, Alajarin M, Steed JW (2004) Molecular Containers Design Approaches and Applications 108 97-168... 

Several commercial calorimeters are available to characterize runaway reactions. These include the accelerating rate calorimeter (ARC), the reactive system screening tool (RSST), the automatic pressure-tracking adiabatic calorimeter (APTAC), and the vent sizing package (VSP). Each calorimeter has a different sample size, container design, data acquisition hardware, and data sensitivity. 

In the approach to acceptable containment design, some other important questions are ... 

To minimize /, you balance the error between the setpoint and the predicted response against the size of the control moves. Equation 16.2 contains design parameters that can be used to tune the controller, that is, you vary the parameters until the desired shape of the response that tracks the setpoint trajectory is achieved (Seborg et al., 1989). The move suppression factor A penalizes large control moves, but the weighting factors wt allow the predicted errors to be weighted differently at each time step, if desired. Typically you select a value of m (number of control moves) that is smaller than the prediction horizon / , so the control variables are held constant over the remainder of the prediction horizon. 

For packages that contain designs, this makes sense Jean s. .. is used to help implement Pat s. . which Malik doesn t need to know about. It s the usual argument for encapsulation at the level of a complete package. For large systems, encapsulation at this level is more useful than it is at the level of individual objects or classes. 

The Accelerating Rate Calorimeter (ARC ) is another adiabatic test instrument that can be used to test small samples. The ARC with the clamshell containment design can handle explosive compounds. It is a sensitive instrument that can indicate the onset of exothermicity where the reaction mixture can be accurately simulated (HSE 2000). ARC testing results can be used in determining a time to maximum rate of decomposition, as well as in calculating a temperature of no return for a container or vessel with specific heat removal characteristics. Further information and references related to the ARC are given in CCPS (1995a) and Urben (1999). 

Are nonrefrigerated containers designed for a minimum 250 (265 in CA) psig pressure ... 

Packaging/container design—The design of the package, bag, syringe, etc., caused or contributed to the error. 

Dispose of silver and lead products in waste containers designated by your teacher. 

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