Steam systems exchanger flooding

Vapor Lock and Exchanger Flooding in Steam Systems... 

Thermal shock In biphase systems, steam bubbles may become trapped in pools of condensate in a flooded main, branch, or tracer line, as well as in heat exchanger tubing and pumped condensate lines. Since condensate temperature is almost always below saturation, the steam will immediately collapse. 

The flow of steam to a process heater or reboiler may also be manipu lated by a valve in the condensate line. The rate of heat transfer is actually changed by partially flooding the exchanger with condensate. Because a change in condensate level is necessary to affect steam flow, this system may respond more slowly than direct manipulation of steam flow, hut it has the distinct advantage of requiring a much smaller valve. 

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