Gravity cycle

Gravity cycles often destabilize a column. Depending on the geometry and violence of fluctuations, they can also cause loss of liquid from the seal loop, vapor backflow into the reflux line, and hammering. 

Gravity cycles tend to be most severe in column bottom lines. These cycles can be quite violent, can dislodge and damage trays and packing support plates, and in some cases, even pull a vacuum deep enough to collapse a vessel (158). Gravity outlet lines should be surveyed with special care to ensure no gravity cycle can form. 

To avoid a gravity cycle, it is best to ensure constant level in the... 

Fatigue strength (5 x 10 cycles) Sand or gravity cast 52 104 172... 

Resin Material Power Factor, 60 cycles Arc Resistance, sec Water Absorption %-24 hr Rockwell Hardness Specific Gravity Mold Shrinkage, in./in. 

AVT Barg BD BDHR BF BOF BOOM BOP BS W BSI BTA Btu/lb BW BWR BX CA CANDUR CDI CFH CFR CHA CHF CHZ Cl CIP CMC CMC CMC COC All-Volatile treatment bar (pressure), gravity blowdown blowdown and heat recovery system blast furnace basic oxygen furnace boiler build, own, operate, maintain balance of plant basic sediment and water British Standards Institution benzotriazole British thermal unit(s) per pound boiler water boiling water reactor base-exchange water softener cellulose acetate Canadian deuterium reactor continuous deionization critical heat flux Code of Federal Regulations cyclohexylamine critical heat-flux carbohydrazide cast iron boiler clean-in-place carboxymethylcellulose (sodium) carboxy-methylcellulose critical miscelle concentration cycle of concentration... 

The spent firel issue is central to long-term fuel cycle policy, not simply because large volumes are threatening to clog the arteries of the nuclear power industry but because spent fuel is the repository of most of the worid s plutonium, some 1000 tons at present, and is already dispersed among the 30-odd countries in which nuclear power plants are located. The indefinite accumulation of these dispersed inventories has proliferation implications that are at least comparable in their gravity to the surplus weapons plutonium inventories in Russia... 

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