| 摘要 |
PURPOSE:To realize the cavitation proof of a regulating valve of the water level in a condensate head tank by a method wherein the air or inactive fluid is introduced to the downstream of the regulating valve. CONSTITUTION:A condenser air extractor 11 branches noncondensable gas on the downstream off a line to lead to gaseous waste disposal system to the downstream of the regulating valve 9 of the water level in a condensate head tank. The condensate left the primary hot well of a condenser 1 flows through a condensate purifying pump 2 and condensate purifying device 3 and 4 and, after being joined with make up water from the condensate head tank 7, led to the condenser through the regulating valve 9 of the water level in the head tank. At this time, the gaseous phase region in a piping ranging from the downstream of the regulating valve to the condenser is increased and consequently two-phase flow is formed by introducing high pressure air or the like at the downstream of the regulating valve. Consequently, the buffer action exerts during the bursting of bubbles generated at the downstream of the regulating valve due to condensing, resulting in reducing the influence to the piping and the like. In addition, at this time, the pressure in the piping rises due to the expansion of the air in the piping, resulting in raising the back pressure of the regulating valve and consequently enabling to prevent cavitation from generating. |
