Multiple rupture

Maximum allowable accumulated pressure for Installation of a multiple rupture disk device (other than fire exposure)... 

Multiple rupture disk device Single rupture disk device... 

In addition to the compression loading, uniaxial extension of entangled PDMS chains have been investigated by pulling a small portion of the material and measuring elastic response before the rupture happens [419]. The multiple ruptures observed in the force-distance curves (Fig. 43) have been interpreted as fractures of an entangled network of PDMS chains formed between the tip and the silica grafted surface. At small deformations, also the capillary forces were shown to contribute in the force. The elastic part of the curves was described us-... 

Fig. 43. Example of multiple rupture obtained with polydimethysiloxane grafted onto silica [419]...

Multiple rupture of steam generator tubes and non-isolable containment the discharge of the SG is carried out in a dedicated pool. 

External events are accident initiators that do not fit well into the central PSA structure used for "internal events." Some "external events" such as fire due to ignition of electrical wires, or flood from a ruptured service water pipe occur inside the plant. Others, such as earthquakes and tornados, occur outside of the plant. Either may cause failures in a plant like internal events. External initiators may cause multiple failures of independent equipment thereby preventing action of presumably redundant protection systems. For example, severe offsite flooding may fli 1 the pump room and disable cooling systems. An earthquake may impede evacuation of the nearby populace. These multiple effects must be considered in the analysis of the effects of external events. 

For lower scaled pressures, velocity can be calculated with the equation proposed by Baum (1987) which produces disintegration of both cylindrical and spherical vessels into multiple fragments (Vj = O.SSoo ). Such a result can also be obtained by use of Figure 6.33. However, actual experience is that ruptures rarely... 

Rupture Discs Used in Multiple Or For Additional Hazard Due To External Heat... 

Figure 7-31B. Rupture disks used in multiple or for additional hazard due to external heat. By permission, Fike Metal Products Div., Fike Corporation.

The CB sheet is coated on the back with microcapsules 5 to 10 pm in diameter, in which leuco dye solution in a nonvolatile solvent is contained. The CF sheet is coated on the front with an acidic coreactant such as reactive clay, zinc salt of salicylic acid derivatives, zinc-modified phenolic resin, etc. On the application of pressure, the microcapsule is ruptured in the area delineated by the pressure pattern, and the leuco dye solution is thereby transferred to the CB sheet to bring about a color-forming reaction with acidic coreactant resulting in a distinct image on the surface of the CF sheet. By inserting a middle sheet (or sheets) called the CFB sheet, which is coated on the front and back with acidic coreactant and microcapsules, respectively, multiple copies can be obtained. 

It is noteworthy that all these reactions are reversible, but under reducing conditions the equilibrium shifts to the right-hand side, and under oxidizing conditions it shifts to the left-hand side. For all resulting binuclear ions at rather low concentration in solutions, reactions take place, accompanied by the rupture of the M-M bond and the formation of unstable mononuclear complexes, which are readily oxidized even by the solvent. At high concentrations of binuclear ions cycloaddition reactions of multiple M-M bonds (these reactions are considered in section 3.5) occur to form stable, under the given conditions, polynuclear clusters. 

The process is run in a semi-batch mode, and multiple reactors are used. There are several possible causes for a loss of control such as insufficient heat removal and loss of agitation. Overpressurization leading to the bursting of rupture discs takes place several times per year, indicating both the clear need for containment but also a need to consider design and control improvements. The reference describes the autoclave rupture disc assembly, procedures for replacement of the discs, the cleaning of the containment vessels, and the routine maintenance procedures for the containment vessels. 

The high selectivity of nickel for demethylation is explained by its high affinity for the adsorption of primary carbon atoms and its high ability to form 1,2-di-adsorbed species.272 On cobalt, where excessive methane formation is characteristic, consecutive C—C bond ruptures are believed to occur via species with multiple attachment to the metal.252... 

Mechanical properties of plastics can be determined by short, single-point quality control tests and longer, generally multipoint or multiple condition procedures that relate to fundamental polymer properties. Single-point tests include tensile, compressive, flexural, shear, and impact properties of plastics creep, heat aging, creep rupture, and environmental stress-cracking tests usually result in multipoint curves or tables for comparison of the original response to post-exposure response. 

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