Staas & Halsey
Coolant pipe blocking device for use in a nuclear power plant
 A coolant pipe blocking device for use in a nuclear power plant is provided to temporarily choke up a coolant inlet pipe to thereby inhibit fluid communication between a reactor and a steam generator, the steam generator having a coolant chamber in communication with the reactor via the coolant inlet pipe and a manway providing access to the coolant chamber. The pipe blocking device includes a plurality of hub segments(42-48) arranged along a longitudinal axis substantially with a uniform spacing to one another and an elongated, flexible, support rod(50) extending in a coaxial relationship with the longitudinal axis for interconnecting and keeping spaced apart the hub segments. A plurality of bladders(52-60) are arranged in an end-to-end relationship with respect to one another and attached to the hub segments to define a series of hermetically sealed air chambers. Each of the bladders is so sized as to, when deflated, move freely into and out of the coolant inlet pipe via the manway and, when inflated, to make a fluid-tight contact with an inner surface of the coolant inlet pipe. In addition, the pile blocking device has a plurality of air hoses(64-68) corresponding to the bladders and projecting respectively into the air chambers to allow air to be evacuated out of and admitted into the air chambers therethrough. 
F Y G
F22B Y02E G21C
inventional additional inventional
Se Yup
Lee