Today most of our electric power is produced by Nuclear Power Plants. Nuclear reactors must be constantly cooled in order to maintain a level of safety. There are two types of pumps used for cooling the reactor, the centrifical pump, and the circulating pump. The cooling water pump is a critical part in a nuclear plant and must be rebuilt continuously to avoid a reactor melt down. Here are some simple instructions that, if followed, will make your rebuild job safe, reliable and quick. First, lock out the electrical breaker that supplies power to the pump.
This will prevent someone from accidentally starting the pump while you are working on it, thus eliminating a dangerous accident. Second, close the suction line and the discharge line to the pump, then open the drain. Opening the drain will relieve any internal pressure in the pump. Third, dismantle the pump housing. Most pumps that are built in the United States have casings that are bolted together with 9/16 bolts. Using a ratchet will save you time.
Fourth, remove the rubber seals from the suction and discharge side of the pump housing and replace. Fifth, inspect the bearings for wear or signs of overheating. Over heating normally causes the bearing to turn bluish in color; if this is observed the bearing should be replaced. Sixth, remove the gasket from the pump housing.
Since the pumps are exposed to high heat a scrapper may be needed to remove it completely. Caution should be used so that the housing is not gouged. Sand the housing and install new gasket. Seventh, bolt the housing back together. Since most cooling water pumps are low pressure, torquing is not required. Eighth, Open suction and discharge valves.
Leave the drain line open until you see a steady stream of wate coming out, then close the drain. This will keep the seals from burning up do to the pump not being primed. Ninth, unlock the breaker and test run the pump. Be sure that the suction and discharge pressures are correct. If the pump develops the right pressures, it is functioning properly.
Tenth, return the pump to service and secure the next pump to be rebuilt. If these steps are followed closely, it should allow you to rebuild your pump quickly, safely, and efficiently, thus lengthening the time between rebuilds.