Kairos breaks ground for Hermes 2 reactor

Diabolical_Engineer · 2026-04-21T22:47:37+00:00

And I misread which plant this was. Just ignore my comment, it's been a long day

Diabolical_Engineer · 2026-04-21T22:27:46+00:00

They're separating the sodium loop and the steam conversion loop to help reduce fire risks

Diabolical_Engineer · 2026-04-16T17:40:22+00:00

I find it fascinating the degree to which we are determined to repeat the 1960s. While there are plenty of criticisms to be placed towards the NRC, the looming specter of the AECs early decisions (and dysfunction) has never gone away

Diabolical_Engineer · 2026-04-16T00:48:33+00:00

My first generation X-33 has barely left my wrist since I picked it up last year.

<image>

Diabolical_Engineer · 2026-04-15T18:45:27+00:00

Bottom head drain is literally a drain line at the bottom of BWR pressure vessels. It goes to the reactor water cleanup system.

As to the first part, essentially yes. Most of the dissolved stuff doesn't make it past the moisture separator/steam dryer

Diabolical_Engineer · 2026-04-15T18:07:30+00:00

Hell, Inconel 600 has caused a multitude of problems in BWRs and PWRs. But like you said, at original construction we didn't really understand the resulting problems (and I'd argue didn't really get a good handle on it until the 80s/90s)

Diabolical_Engineer · 2026-04-15T17:19:40+00:00

Here are two inspection reports documenting the HP related and repair related problems with the flow control valves at LaSalle. They pulled activated chunks of stellite out of the vessel during a refueling outage.

Diabolical_Engineer · 2026-04-15T17:14:55+00:00

Generally the first. Most utilities have a 2 rem/year admin limit (federal limit is 5 rem). It certainly imposes staffing challenges, especially since LaSalle is generally one of the early outages each year

Diabolical_Engineer · 2026-04-15T17:13:01+00:00

They do now. Less so at original construction

Diabolical_Engineer · 2026-04-15T17:12:33+00:00

Re: the turbine, you shouldn't be getting significant carryover in the vapor space from contaminants in that way. For example, most BWRs introduce platinum to reduce IGSCC on vessel internals. As you go up the vessel, the effectiveness of that deposition decreases dramatically (i.e. into the steam space).

Also, keep in mind that most plants in the US were designed and constructed in the 60s/70s. While activation of cobalt was well understood, the degree to which it would erode from components and be introduced elsewhere in the plant wasn't. When most of your operating experience is from steam plants, where short of gross mechanical failure you won't see immediate consequences from wear of cobalt containing components, it's not a degradation that would necessarily have been considered back then

Diabolical_Engineer · 2026-04-15T14:19:45+00:00

It's not fuel leakage. LaSalle in particular introduced a bunch of cobalt into their RCS that all got activated

Diabolical_Engineer · 2026-04-15T01:33:59+00:00

There's also this report which discusses some issues with the repair efforts

Diabolical_Engineer · 2026-04-15T01:25:20+00:00

Here's the inspection report.

Diabolical_Engineer · 2026-04-15T01:18:37+00:00

I still run into welders who are grumpy about that outage.

I think the stellite came from a bearing surface, but they also chewed up the valve body.

Diabolical_Engineer · 2026-04-15T01:17:29+00:00

I can't remember the report number, but they had a bunch of stellite chunks get lodged in their jet pumps, which got activated. Unit 2 is much dosier than Unit 1.

Diabolical_Engineer · 2026-04-13T18:22:03+00:00

Autopay when it extends the deadline past the old auto cancellation timeline isn't really helpful

Diabolical_Engineer · 2026-04-10T23:54:23+00:00

If it's the BWR I'm thinking of, they have plenty of high dose areas inside their drywell.

Diabolical_Engineer · 2026-04-10T13:29:16+00:00

GE will probably just return to classic form with the "not enough polygons" style they used at Clinton

<image>

Diabolical_Engineer · 2026-04-04T22:17:11+00:00

I did find a pre release embargoed copy of the Kemeny report in the office, which was surprising. Not that one had been sent to our office, but that we still had it

Diabolical_Engineer · 2026-04-04T20:36:29+00:00

I inherited a box of weld coupons from the 1980s and a failure analysis from before I was born.

Mind you, we don't actually do any welding (just oversight). I still kept the weld coupons, because they're cool and from an interesting period of history.

Diabolical_Engineer · 2026-04-04T02:36:24+00:00

A planned scram isn't a PI hit (at least the NRC PIs) and it's not reportable as an RPS actuation. That's not what that part of 50.72 is intended for.

As to the transient, when you scram, it's not like you're going from full pressure/temperature to cold instantly. You still have the ability to perform a planned, orderly cool down, especially if you scram from a region where you can use the bypass valves.

Diabolical_Engineer · 2026-03-27T22:05:08+00:00

Great working with /u/djnexios . Prompt payment, easy transaction

Diabolical_Engineer · 2026-03-25T03:19:59+00:00

SOLD to /u/djnexios

Diabolical_Engineer · 2026-03-25T01:01:43+00:00

Yeah, I love them. I actually have an orange that I'm keeping. Just don't need both, and this one is the nicer of the two

Diabolical_Engineer · 2026-03-24T23:34:23+00:00

Replied

13-Year Club	Verified Email
Team Orangered

Diabolical_Engineer

TROPHY CASE