ML031810397
| ML031810397 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/13/2003 |
| From: | Tom Gurdziel - No Known Affiliation |
| To: | Grobe J Division of Reactor Safety III |
| References | |
| Download: ML031810397 (2) | |
Text
9 Twin Orchard Drive Oswego, NY 13126 June 13,2003 Mr. John A. Grobe, Director Division of Reactor Safety US Nuclear Regulatory Commission 801 Warrenville Road Lisle, IL 60532-4351
Dear Mr. John A. Grobe:
Bolting I am not comfortable with my current impressions of Davis-Besse bolting practice. I think that the maintenance staf has, in the past, indiscriminately tightened bolts on leaking equipment. Specifically, I think that this was the case on that valve that had two or three of four bolts corroded by boric acid (pressurizer spray, I think), and especially, the bolts (or nuts on studs) at the cover to casing joint of the reactor coolant pumps.
However, my basic information is sketchy on the reactor coolant pumps. I believe that I mentioned these to you or Christine as having 0 ring type gaskets, but the 7 page memo I read, (ADAMS number ML03 153018 I), mentioned Flexitallic style gaskets.
I find the following bolting questions interesting:
Is any bolting controlled at Davis-Besse now or in the past?
Have any bolts or studs been replaced because of a change in original characteristics due to age, radiation, or overtightening? (An example might be the reactor head studs.)
Are there any currently calibrated torque wrenches at Davis-Besse?
Is there a currently approved procedure for the use of torque wrenches?
When is the last time QNQC has documented an inspection of bolting?
Is any bolting considered a skill of the trade?
Have any bolt failures typical of over tightened bolts been identified at Davis-Besse?
What is the arrangement of gaskets for the reactor coolant cover to casing gasket@)?
What type of gaskets are used?
Are the original design requirements of the gaskets in use being met?
If0 ring gaskets are used, do they have pressure equalizing holes in them that are not Are the (cover and casing) sudaces on both sides of the gaskets plane within specified tolerances?
clogged?
Are any recesses or groves for the gaskets filled with boron so that they do not provide adequate clearances?
What is the vendor specified life of the gaskets currently installed?
If1 can buy a Briggs and Stratton engine from a local hardware store in Oswego, read the operating instructions, and not find a requirement to tighten the head bolts after 25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br /> of service (or any other time), why would I expect to see a vendor suggestion at a nuclear site to retighten bolts aRer a few thermal cycles? (ML031530181) After all, they dont do that to the reactor head bolts, do they?
Primary reactor coolant leakage I was disappointed to read, in either the March or April public meeting transcript that a leak through the first gasket of the reactor coolant pumps is not a primary coolant leak. I dont accept this line of thinking at all.
Criminal Investigations What is taking so long? Ifthe total loss of all structural steel in the reactor upper head does not reflect criminal behavior on the part ofthe plant operator, maybe it does someplace else.
This is letter twenty two. It needs no reply.
Tom Gurdziel Copy: D. Lochbaum