ML19296A554

Forwards List of Items to Be Addressed by Harbison & Walker Refractories & OPS at 790507-08 Meeting in Jacksonville,Fl

ML19296A554
Person / Time
Site:	Atlantic Nuclear Power Plant
Issue date:	04/24/1979
From:	Swanson D AEROSPACE CORP.
To:	Marchese A Office of Nuclear Reactor Regulation
References
NUDOCS 7905030339
Download: ML19296A554 (5)

Text

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b Y$f T II E AEROSPACE C O ll P O II A T I O N d Post Office lh>x 92957, l.os A ngeles, Galifornia 90009, Telephone: (213) 618-5000 24 April 1979 Mr. Andrew Ma rchese, MS-268 Division of Project Management U. S. Nuclear Regulatory Commission Wa shington, D. C. 20555

Dear Andy:

I have enclosed a list of items to be addressed by Harbison and Walker Refractories and by Offshore Power Systems at the 7-8 May 1979 Meeting in Jacksonville. Copies of the questions have been sent to Dr. D. Walker and Mr. Paul Schlett.

Sincerely, r; , -t D. G. Swanson Member Technical Staff Materials Sciences The Ivan A. Getting Laboratories DGS:fr Enclo sure 7

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An Equal Opportunity Employer ca .u orrica. tocarao ar uso ..r at secu~oo .outa va o it .cou~oo. c.aro. m Ag

Items to be Addressed by Harbison and Walker Refractories and Offshore Power Systems at the 7-8 May 1979 Meeting

1. Questions Specifically Keyed to OPS Report No. 36A 59

1. Pace III-8, Line 13 How will locking the bricks into the ladle steel shell help when the shell will melt on contact with the molten core debris ?

2. Pace III-8, Lines 18, 22 What is the difference between chemically bonded and burned MgO?

What is the melting temperature and porosity of each type of brick ?

Can we obtain samples of each brick?

3. Page III-12, Line 3 Please define a static list.

A value of 0. 50 seems very small; what would be the con-sequences of a 20 - 30 list ?

What is the worse list possible and how can it arise?

Are the sidewalls thick enough to cope with a large list?

A related question concerns the extent of lateral erosion.

Is the wall thickness great enough to cope with a lateral erosion that is equal to the vertical erosion?

4. Page IV-11, Line 3 Do they have a reason for believing that iron oxides will be mixed in with UOz instead of being in a separate layer on top of the molten iron?

What are the implications if this occurs ?

/. Page IV-11, Line 3 (continued)

What are the other constituents of the molten core, and in what quantities are they present?

Can you provide a best estimate of the melt composition and the type of steel?

5. Page V-5, c-11, Line 2 Why is a substantial layer of iron oxide unlikely?

Do you have any data?

What is the industry experience and can you provide refe rence s ?

6. Pace V-7, Line 2 Can you cite a specific data, reports, etc. , and suppl, these to us ?

7. Pace' V-7, b-iii, Line 1 UO2 is heat-generating and, consequently, it isn't clear that it will freeze quickly. Have you performed any calculations to determine whether freezing will occur?

Can you provide a copy or report on any calculations performed in this area?

8. Page V-8, c-iii, Line 4 What materials are used in this application that are les s susceptible to thermal shock than Harklase brick?

9. Page V-15 Can you provide any references to reports on the metal industry experience with MgO brick floatup?

Can you provide any references for the industrial experience with the thermal shock and mechanical shock resistance of MgO bricks ?

10 Appendix C, Table 1 What is the porosity of TOPEX-S?

II. Harbison and Walker Letter

11. Section 1.

Will a mortar be used in the joints ?

Will a mortar be used anywhere?

What are the properties of any mortars proposed for use?

12. Section 4.

What is the inert, ceramic fibrous material and what is it to be used for ?

13. Section 6.

What are the physical and chemica1 properties of the HAMIX-FE-MgO ramming mix?

14. Section 9.

Can they provide more details on the brick layout, the initial spacing between bricks and the design temperature range ?

At what temperature will spacings between bricks close?

What is the maximum temperature, if any, before the bricks are destroyed by thermal expansion?

Will low-temperature melts go through the spaces between bricks ?

Will the brick layout be such that spacings for successive layers will not be directly over each other?

What is the effect of the loss of one or more bricks on the arch?

What is the probability of brick loss through cracking or other means due to normal use or manufacturing defects ?

15 Section 10.

How is Harklase treated to increase hydration resistance?

III. General Questions

16. We are concerned that moisture may collect in the core ladle. Is there a provision for a sensor to detect moisture and is there a drain?

Will water degrade the MgO bricks?

Is a steam explosion possible when molten UO2 comes into contact with soaked bricks?

17. Can thermoco' ples be inserted in the core ladle to provide a means of locating the pr ogress of a melt front?

18. Please provide copies, where available, of the phase diagrams for all combinations of MgO and the expected constituents of molten core debris.

Please estimate the melting temperature of MgO brick in the presence of tl ese constituents and provide us with the basis for this estimate.

Please estimate the expected temperature of the molten core debris and advise us of the methods used in this estimate.