plant designs

[wlrun3@aol.com]

...sphere...mark 1 (torus)...mark 2 (over-under...suppression pool)...mark 3...are clinton, perry, river bend, grand gulf the only mark 3 containment bwr's...

[wlrun3@aol.com]

   
   ..."Recirculation systems are of two types, variable speed pumps and valve flow control."   Bartlett Nuclear Inc., Light Water Reactor Systems Training Material...

   ...are there any operating bwr's using the valve flow control recirculation system...



   

[NucEng for Hire]

recirc flow control via flow control valves began with bwr/5 and into bwr/6

bwr/5
columbia
nine mile point 2
lasalle 1 & 2

bwr/6
perry
clinton
grand gulf
river bend

[M1Ark]

I worked at a GE-4 and we had variable speed recirc pumps.

[wlrun3@aol.com]

 

...concerning bwr containments (sphere, mark 1-torus, mark 2-"over-under" with suppression pool, mark 3-suppression pool below and to the sides of the drywell)...

   ...are the mark 3 containments unique to the bwr 6s (clinton, perry, river bend, grand gulf)...

[NucEng for Hire]

   ...are the mark 3 containments unique to the bwr 6s (clinton, perry, river bend, grand gulf)...

yes; there are 4 bwr/6s in the US and 4 mark III containments, and they are the same plants.

[wlrun3@aol.com]

...four pwr's have facades (ginna, millstone 2, point beach 1 & 2)...was the intention solely aesthetic...

[RDTroja]

...four pwr's have facades (ginna, millstone 2, point beach 1 & 2)...was the intention solely aesthetic...

I don't know, but Kewaunee painted their containment building blue and hid their switchyard... just looks like a farm with a MUCH bigger silo than all the neighbors...

[Fermi2]

IIRC a few of the BWR 5 and 6 abandoned the Flow Control Valve Scheme and went to a modified version where the valves control to something like 20% open the are full opened and then Recirc Speed is adjusted. I might be wrong on this.

Back in the Mid 90s there were LOTS of BWR SCRAMS reported either due to FCV Lock Up or FCV Failing open or closed when they shouldn't have.

IMO The BWR 4 got it right with Variable Speed Recirc Pumps. Especially once digital controls became available because GEMACs SUCKED!

Mike

[Len61]

VFD's are a dream compared to our old recirc MG sets. Those old scoop tubes had way to much "slop", especially at high RPM. We can easily maintain RX power within 1 or 2 MWT of full power, so much so that there is little margin for error.

[Fermi2]

Fermi2 used Recirc MGs. Spare parts were a nightmare but IIRC we always maintained within 2MW of rated thermal on an 8 hour average.

Mike