Blowers, fans, and auxiliaries

Bloners. There are three half-capacity blowers in parallel, one of which serves as a spare, for cooling during normal operation of the reactor. Each 

The blowers are electric-motor driven and receive power from the normal commercial electrical supply only. Extra puTleys are provided with the blowers to provide for the slower speeds at reduced requirements. These pulleys will adequately cover the range from 700 to,1000 Ib/min. 

Valves. There are butterfly valves at both inlets and outlets oif ail blowers and fans. The valves oh the inlet sides are manually operated while the valves on the exhaust sides are air operated. The valves on the exhaust sides can seal airtight to permit removal of a blower or fan.without outward leakage of radioactive air. The valves on the inlet. sides do not have to be absolutely airtight since any leakage here will,be directed into the reactor air system. 

Since the blowers are of the. positive displacement type, it is necessary to have both the inlet and outlet valves open when. the blowers are.operating. To ensure this, limit switches are provided on both inlet-.and outlet va.lyes. These switches require both valves to be open before the blowers can be s tar ted.  

because of the use of positive displacement blowers, it was necessary to provide h by-pass around all the blowers and fans so that the stack draft will be available to provide a flow of air through the reactor air system. The by-pass is provided by a valve between the plenum chamber ahead of the fans and blowers and the exit duct leading to the stack. This valve will be operated manually..  

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