Plant name for the primary-side channel head of a PWR steam generator, a bowl-shaped chamber divided into hot-leg and cold-leg halves beneath the tubesheet. During outages workers or robots enter through manways to install nozzle dams, inspect and plug tubes. Dose rates inside are among the highest routinely entered in a plant, so bowl work is planned to the second and is a major share of outage dose.
Robot's in the bowl on the hot leg side, eddy current team can start at 0600.
Also heard as
- channel head
- SG bowl
- steam generator bowl
Related terms
Jumper
A worker who makes brief entries into very high radiation spaces, absorbing a large dose allowance in minutes.
High radiation area
A posted area where a person could receive more than 1 mSv (100 mrem) in an hour at 30 cm from a source.
Crud
Corrosion products that deposit on fuel and in reactor piping, become radioactive and drive most plant dose.
ALARA
As low as reasonably achievable: the principle of keeping doses as low as practical, not just below limits.