ML20101B043
| ML20101B043 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley, Sequoyah, Farley  |
| Issue date: | 02/28/1996 |
| From: | WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | Russell W NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20101B029 | List: |
| References | |
| CAW-96-935, NUDOCS 9603140049 | |
| Download: ML20101B043 (43) | |
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Westingflouse Energ Systems Nuclear Services Dmston Electric Corporation 5 333 Pittsbutgh Pennsylvama 15230-0355 February 28,1996 CAW-96-935 Document Control Desk US Nuclear Regulatory Commission Washington, DC 20555 Attention: Mr. William T. Russell, Director APPLICATION FOR WITHHOLDING PROPRIETARY INFORMATION FROM PUBLIC DISCLOSURE
Subject:
"EPRI ARC Database for 3/4" and 7/8" Diameter Tubes and Updated ARC Correlation for 7/8" Diameter Tubes" (Proprietary)
The proprietary information for which withholding is being requested is further identified in Affidavit CAW-96-935 signed by the owner of the proprietary information, Westinghouse Electric Corporation.
The affidavit, which accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR Section 2.790 of the Commission's regulations.
Accordingly, this letter authorizes the utilization of the accompanying Affidavit by Duquesne Light Company.
Correspondence with respect to the proprietary aspects of the application for withholding or the Westinghouse affidavit should reference this ' letter, CAW-%-935, and should be sddressed to the undersigned.
Very truly yours, N. J.
iparuto, Manager JJM/bbp Regulatory & Engineering Networks Enclosures
~-
cc:
Kevin Bohrer/NRC(12H5)
~~
CAW 935/NSDU93 9603140049 960307 PDR ADOCK 05000334 P
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l Proprietary Information Notice l
Transmitted herewith are proprietary and/or non-proprietary versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific review and approval.
l In order to conform to the requirements of 10 CFR 2.790 of the Commission's regulations concerning the protection of proprietary information so submitted to the NRC, the information which is proprietary in the proprietary versions is contained within brackets, and where the proprietary l
l information has been deleted in the non-proprietary versions, only the brackets remain (the information that was contained within the brackets in the proprietary versions having been deleted).
The justification for claiming the information so designated as proprietary is indicated in both versions by means of lower case letters (a) through (f) contained within parentheses located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information. These lower case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.790(b)(1).
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CAW 935/NSD093
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i Copyright Notice
'Ihe reports transmitted herewith each bear a Westinghouse copyright notice. The NRC is permitted to make the number of copies of the information contained in these reports which are necessary for its internal use in connection with generic and plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, permit, order, or regulation subject to the requirements of 10 CFR 2.790 regarding restrictions on public disclosure to the extent such information has been identified as proprietary by Westinghouse, copyright protection notwithstanding. With respect to the non-proprietary versions of these reports, the NRC is permitted to make the number of copies beyond those necessary for its internal use which are necessary in order to have one copy available for public viewing in the appropriate docket files in the public document room in Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient for this purpose. Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.
CAW 935'NSD093
4 o
CAW-96-935 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:
ss COUNTY OF ALLEGHENY:
Before me, the undersigned authority, personally appeared Nicholas J. Liparuto, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of Westinghouse Electric Corporation (" Westinghouse") and that the averments of fact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief:
\\
h Nicholas J. L lo, Manager Regulatory & Engineering Networks Sworn to and subscribed before me this J[
day of
,1996 O
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rawIsa Rose Marie Payne,Notyy Putic kkwvoevmeBoro. Abgtm/ ounty C
My Commcsion Egros tkx 4,1996 Monter,PernemaAssocmond thwe 1929C-DLC.1:0.".896
C CAW-96-935 o
(1)
I am Manager, Regulatory & Engineering Networks, in the Nuclear Services Division, of the Westinghouse Electric Corporation and as such, I have been specifically delegated the 1
l function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rulemaking proceedings, and am authorized to apply for its withholding on behalf of the Westinghouse Energy Systems Business Unit.
(2)
I am making this Affidavit in conformance with the provisions of 10CFR Section 2.790 of the Commission's regulations and in conjunction with the Westinghouse application for withholding accompanying this Afridavit.
(3)
I have personal knowledge of the criteria and procedures utilized by the Westinghouse Energy Systems Business Unit in designating information as a trade secret, privileged or as l
l confidential commercial or financial information.
1 (4)
Pursuant to the provisions of paragraph (b)(4) of Section 2.790 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.
l (i)
The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghonse.
(ii)
The information is of a type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence. The application of that system and the substance of that system constitutes Westinghouse policy and provides the rational basis required.
i 1
Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:
1929C-DLf-2:02?a96
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4 CAW-96-935 o
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(a)
The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.
(
'(b)
It consists of supporting data, including test data, relative to a process (or l
component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage, e.g., by optimization or improved marketability.
i (c)
Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.
t 1
(d)
It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.
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(e)
It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to i
1 Westinghouse.
(f) -
It contains patentable ideas, for which patent protection may be desirable.
l (g)
It is not the property of Westinghouse, but must be treated as proprietary by Westinghouse according to agreements with the owner.
I There are sound policy reasons behind the Westinghouse system which include the i
following:
I (a)
The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors. It is, therefore, withheld from disclosure to protect the Westinghouse competitive position.
1929C-DLC-3:022896
i
- CAW-96-935 0
(b)
It is information which is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information.
(c)
Use by our competitor would put Westinghouse at a competitive disadvantage by reducing his expenditure of resources at our expense.
(d)
Each component of proprietary information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage. If competitors acquire components of proprietary information, any one component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage.
l (e)
Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries.
(f)
The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage.
(iii)
The information is being transmitted to the Commission in confidence and, under the provisions of 10CFR Section 2.790, it is to be received in confidence by the Commission.
(iv)
The information sought to be protected is not available in public sources or available information has not been previously employed in the same original manner or method to the best of our knowledge and belief.
I (v)
The proprietary information sought to be withheld in this submittal is that which is I
appropriately marked in letter NSD-SGD-1212, "EPRI ARC Databases for 3/4" and l
7/8" Diameter Tubes and Updated ARC Correlation for 7/8" Diameter Tubes", dated February 26,19% (Proprietary), being transmitted by the Duquesne Light Company letter and Application for Withholding Proprietary Information from Public 1929C-DirM22896
I e CAW-96-935 Disclosure, to the Document Control Desk, Attention Mr. William T. Russell. The proprietary information as submitted for use by the Duquesne Light Company for the Beaver Valley Power Station is expected to be applicable in other licensee submittals in response to certain NRC requirements for justification of steam generator tube integrity evaluations.
This information is part of that which will enable Westinghouse to:
(a)
Perform steam generator tube integrity evaluations.
Further this information has substantial commercial value as follows:
(a)
Westinghouse plans to sell the use of similar information to its customers for purposes of meeting requirements for licensing documentation.
(b)
Westinghouse can sell support and defense of the technology to its customers in the licensing process.
i Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar methodologies and licensing defense services for commercial power reactors without commensurate expenses. Also, public disclosure of the information would enable others to use the information to meet NRC requirements for licensing documentation without purchasing the right to use the information.
i The development of the technology described in part by the information is the result i
of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money.
1929C-DLC 5:022896 m,
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< CAW-96-935 In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended for developing testing and analytical methods and performing testing, Further the deponent sayeth not.
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1.0 Updated ARC Correlations for 7/8" Tubes This section reports on the evaluations performed which utilized the results ofleak rate and burst testing of tube sections removed from SGs at utility sites in the United States after the publication of the original EPRI database for 7/8" diameter SG tubes (NP-7480-L, Volume 1). The results of the destructive examinations of the tube sections were reported in utility specific reports, and will be summarized in the complete data update report to follow. The additional pulled tube data ger-mane to the APC correlations, and the bobbin amplitudes for APC applications, will be contained in a table in the complete update report to be issued at a later date. The additional data consist of results from pulled tube sections from Beaver Val-ley 1 (SG-95-06-006, May 1995), Farley 2 (SG-95-07-010, July 1995), Sequoyah 1 (SG-96-01-007, January 1996), and Farley 1 (SG-96-01-003, January 1996). The results of the leak and burst tests are compared herein to the database of similar test results for 7/8" outside diameter SG tubes, and the effect ofincluding the new test data in the reference database is evaluated. In summary, the applica-ble test data are consistent with the database relative to the burst pressure, the probability ofleak, and the leak rate as function of bobbin amplitude correlations for 7/8" diameter tubes. The comparisons and evaluations follow. Suitability for Inclusion in the Database The morphology of the degradation of each indication considered herein was reviewed relative to the EPRI guidelines for inclusion / exclusion of tube specimen data in the alternate plugging criteria (APC) database. The findings of the reviews were recorded in documents prepared for each utility as the data were obtained. The details of the reviews will be included in a comprehensive report to be issued at a later date dealing with multiple tube sizes. None of the reviews revealed information that would lead to a conclusion that the data considered in this section should not be included in the database. Therefore, the correlations reported herein should be considered applicable to the use of APC for indications in 7/8" diameter tubes in Westinghouse SGs and constitute the analyses of the updated database. 1.1 Free Span Burst Correlation The burst pressure database used in this report for 7/8" tubes consists of the EPRI recommended database, plus test results from tube R11C60-1 removed from D.C. Cook Unit 1. The results for this tube section were abnormally high, but the degradation morphology did not meet all of the exclusion criteria developed for degradation with abnormally high burst pressures, hence it was retained in the correlation database. The results from ten (10) burst tests, performed on tube specimens which exhibited a non-zero bobbin amplitude at a TSP elevation location, were considered for evaluation. A plot of the burst pressures of the additional specimens is depicted on Figure 1-1 relative to the burst pressure correlation devel-DAAPe\\EPRI 78.296 1-1 02/24/96
l op:d using the reference database and relative to a 95% confidence band to contain 90% of the population of burst pressures. 1. A visual examination of the data relative to the EPRI database indicates that the burst pressures measured fall within the scatter band of the refer-ence data. 2. Nine, i.e.,90%, of the data points fall within a 95%/90% tolerance interval (approximate) about the regression line (95% confident to contain 90% of the underlying normal population). 3. One, i.e.,10%, of the data points falls outside of the 95%/90% tolerance band about the regression line. In summary, the visual examination doesn't indicate any significant departures from the reference database. Although the burst pressure is less than would have been expected for one of the indications, the appearance of one such indication in the additional ten data points is not significantly improbable. Moreover, the bobbin amplitude for this indication increased from 4 volts before removal to 12 volts after, thus, the burst pressure could have been reduced as a consequence of mechanical deformation from the tube removal activities. Since the regression line for this analysis represents the mean and median burst pressure to be expected from the parent population, it would be expected that additional data should fall about half above and half below the line. For the additional data analyzed, six (6) values were above the line and four (4) values below the line. For ten values drawn at random from the population of bursts, the probability that the split would be five above and five below is about 25%, and the probability that the results would be split six/four in either direction is 41%. Thus, distribution relative to above or below the regression line is not unusual. In addition, the average difference in the observed burst pressure relative to the predicted burst pressures is only 1.1%. Finally, al-though the tube data are from SGs at multiple plant sites, an examination of the normalized residuals relative to the predictions of the reference correlation equa-tion was performed. The results of this analysis are shown on Figure 1-2 where the distribution of observed deviates is compared to those expected from a normal distribution. There doesn't appear to be any significant systematic departure from normality. Since the additional burst pressure data were not indicated to be from a separate population from the reference data, the regression analysis of the burst pressure on the common logarithm of the bobbin amplitude was repeated with the additional data included. A comparison of the regression results obtained by including these data in the regression analysis is provided in Table 1-1. Regression predictions ob-DAAPC\\EPRI 78.296 1-2 02/24/96
. t'ained by including thess data in the regression analysis are shown on Figure 1-3. The appropriate regression equation for future ARC analyses is, P3 = 7.592'- 2.370 log (Volts), (1-1) with a SLB structural limit of 8.6 volts. The changes to the correlation are: 1. The intercept of the burst pressure, P, as a linear function of the common 3 logarithm of the bobbin amplitude regression line is increased by 0.48%. This has the effect ofincreasing the predicted burst pressure as a function of the bobbin amplitude. I 2. The absolute slope of the regression line is increased by 2.19%, i.e., the slope is more steep. This has the effect of decreasing the burst pressure as a function of bobbin amplitude for indications greater than about 3 volts. 3. There is an increase in the standard error of the residuals of 1.38%. The effect of this change would be reflected in a slightly larger deviation of the 95% prediction line from the regression line. i The net effect of the changes on the SLB structural limit (1.43 APsts ), using 95%/95% lower tolerance limit material properties, is to decrease it by 0.2 volts, i.e., from 8.8 volts to 8.6 volts. The increase in the slope relative to the increase in the intercept, and the increase in the standard error coupled with the fact that the structural limit is also decreased indicates that the probability of burst would also increase for bobbin indications over the structural range ofinterest. Based on the relatively small change in the structural limit, the change in the probability of burst would also be expected to be small. 1.2 Probability of Leak Correlation As for the burst pressure correlation, there are ten (10) additional data pairs that were considered relative to the reference database and the probability ofleak (POL) correlation to the common logarithm of the bobbin amplitude. Figure 1-4 illus-trates the additional data relative to the reference correlation. All of the specimens except one exhibited POL behavior commensurate with expectations indicated by the reference database and regression curve. The single exception was an indica-tion with a bobbin amplitude of 4.03 volts that exhibited leakage, thus becoming the indication with the second lowest voltage of the indications that leaked in the database. 4 i Based on the reference curve, the POL for the leaking indication is 0.133, thus, roughly 1 in 7 indications with an amplitude of 4.03 volts would be expected to leak. Had the expectation been 1 in 20, statistically anomalous behavior could a have been suspected. The indication that leaked was the same indication that D:\\APC\\EPRI 78.296 1-3 onness
exhibited a lower than expected burst pressure. It is strongly suspected that this i indication experienced ligament tearing during the tube pull as indicated by the maximum 96% corrosion depth resulting in post-pull Argon leakage at 200 psid and the increase in bobbin amplitude from 4.03 to 12.2 volts. However, since it is ) difficult to prove that the wall thickness ligament would not have torn during postulated SLB conditions, the indication is to be retained in the EPRI database. In conclusion, data examinations revealed no significant evidence ofirregular results, i.e., outlying behavior is not indicated. In order to assess the quantitative effect of the new data on the correlation curve, the database was expanded to include the additional data points and a Generalized Linear Model regression of the POL on the common logarithm of the bobbin ampli-tude was repeated. A comparison of the correlation parameters with those for the reference database is shown in Table 1-2. These results indicate: 1. A 9.7% increase (smaller negative value) in the logistic intercept parame-ter. 2. A 6.2% decrease in the logistic slope parameter. j 3. The absolute values of the parameters' covariance matrix changed by 26.5% to 34.5%. These changes may have a significant impact on the POL values used during the Monte Carlo Simulations, but may not have a significant impact on the 95% confidence bound on the total estimated leak rate from a single SG. 4. The Pearson standard error decreased by 7.2% from 0.640 to 0.594. This is a negative indicator since the ideal value would be 1.0, but is notjudged to be significant. An additional evaluation was performed which demonstrated that most of the changes in the distribution parameters are a result ofincluding the 4.03 V indica-tion that leaked. In order to assess whether or not these changea are significant, the reference correlation and the new correlation were also plotted on Figure 1-4. An examination of Figure 1-4 reveals a moderate change in the correlation up to about 5 V, with a 31% increase at 4.03 V. A tabular summary of POL predictions before and after including the additional data point is provided as Table 1-3. For indications with amplitudes less than 1.0 volt, the POL increases by a factor of 2 to
- 4. The POL for indications of 3 volts increases by about 50%, while the change in the POL is not significant for indications of 8 volts and greater.
When the total leak rate is determined using the leak rate to bobbin volts correla-tion, the resulting value can be quite insensitive to the form of the POL function. So, the effect of the changes in the parameter values and variances would be expected to be small or insignificant relative to the calculation of the 95% confi-dence bound of the total leak rate from a SG. However, when the leak rate is D:\\APC\\EPRI-78.296 1-4 02/24/96
considertd as independent of the voltage, as for the current APC databa:s, the increase in POL will more directly affect the estimated total leak rate. 1.3 Free Span SLB Leak Rate Correlation for 7/8" Tubes I As previously noted, only one of the specimens exhibited leakage at SLB operating conditions. The test leak rate value corresponded to 2.19 lph at the SLB tempera-ture and pressure difference conditions. The correlation ofleak rate to bobbin voltage exhibits a p-value of 6.5% for the slope parameter using the reference database, and a value of 6.4% with the additional data point. Based on the require-ments stipulated in NRC Generic Letter 95-05 for voltage based plugging criteria, the use of the correlation in performing Monte Carlo simulations to estimate the total leak rate from a SG is not considered to be justified. Figure 1-5 illustrates the new data point relative to the distribution predicted mean using the reference database and relative to a lower 95% confidence limit for a predicted leak rate from the distribution. Also illustrated on Figure 1-5, is the relation of the data point to the regression fit (median of the log-normal distribution) and to the expected leak rate (mean of the log-normal distribution) based on the regression analysis of the leak rate on the bobbin amplitude. The common logarithm (log) of the test leak rate,0.340, is lower than the mean log leak rate for the reference database, 0.576, but is well within one standard devia-tion of that value. The effects ofincluding the data point in the database on the estimated parameters of the leak rate distribution are tabulated in Table 1-4. The estimated mean and standard deviation of the population ofleak rates are de-creased, hence, predicted leak rates from Monte Carlo simulations and the 95% confidence bound on the total leak rate from a single SG will be reduced. For clarification, the values listed in Table 1-4 for the mean, p, and standard deviation, o, of the population ofleak rates are derived from the sample values of the log leak rate. These are the expected leak rate parameters to result from a simulation of the log leak rates using the NRC accepted leak rate simulation method as described in WCAP-14277. 1.4 Summary / Conclusions The review of the effect of the additional data indicates that the SLB structural limit burst pressure will not be significantly changed by the inclusion of the data. Therefore, it is likely that the conclusions relative to EOC probability of burst and based on the correlation obtained using the reference database would not be signifi-cantly affected. The probability ofleak correlation to the common logarithm of the bobbin ampli-tude is moderately changed by the inclusion of the data, leading to the expectation of predicting slightly larger 95% confidence bound leak rates. At the same time, the mean and standard deviation of the leak rate distribution are decreased, leading to the expectation oflower 95% confidence bound leak rates. It may be D5APC\\EPRI 78.296 1-5 02/24/96
ekpected thrt the incr: ass in ths POL will be at least partially offs t by ths decrease in the predicted leak rates. 5 i t 4 d 4 D:\\APC\\EPRI 78.296 1-6 024 #96
I l l Table 1-1: Effect of Additional Data on the 7/8" Tube Burst Pressure vs. Bobbin Amplitude Correlation P3 = a1 + a2 og(Volts) l Reference Database with New / Old i Parameter Database Value additional Ratio a 7.5557 7.5920 1.0048 i a2 -2.3194 -2.3700 1.0219 r 82.7% 81.84 % 0.9900 og,,,, 0.817 0.828 1.0138 N (data pairs) 70 80 tAsgs;655);a p Value for a 5 10'27 1 10-a 9 104 2 Reference o 68.78 ksim gyggggggg ggjggggg r Notes: (1) This is the flow stress value to which all data was normalized prior to performing the regression analysis. This affects the coefficient and standard error values. The corresponding values for a flow stress of 75.0 ksi can be obtained from the above values by multiplying by 1.0904. D.MPC\\EPRI-78.296 1-7 024 W96
1 Table 1-2: Effect of Additional Data on the 7/8" Tube Probability of Leak Correlation l -[D:+pigW l Pr(Leak) = 1+e Reference Database with p, Change Database additional -6.8974 -6.2269 -9.7% i 8.3507 7.7739 -6.9% 2 V m. 3.4998 2.2911 -34.5% ii V -3.8456 -2.6004 -32.4% 12 V 4.5821 3.2955 -26.1% 22 U DoF ) 97 107 (is!!!H^sg(vis Deviance 25.09 28.90 15.2 % Pearson SD 64.0 % 59.4 % -7.2% Notes: (1) Parameters V are elements of the covariance matrix of y the coefficients, j, of the regression equation. (2) Degrees of freedom. D:\\APC\\EPRI 78.296 1-8 02/24/96
Table 1-3: Effect of Additional Data on 7/8" Tube Probability of Leak Predictions Bobbin EPRI/NRC w/ additional New / Old Amplitude Database Database (Volts) POL POL 0.100 2.39 10'7 8.31 10'7 3.48 0.200 2.95 10~6 8.63 10-6 2.93 0.300 1.28 10-5 3.39 10^5 2.64 0.500 8.18 10'6 1.90 10 2.33 4 4 4 0.600 1.58 10 3.52 10 2.22 ~ 4 4 0.800 4.50 10 9.29 10 2.07 4 1.000 1.01 10 1.9710-a 1.95 2.000 0.0123 0.0201 1.63 3.000 0.0515 0.0746 1.45 4.030 0.1367 0.1793 1.31 5.000 0.2572 0.3115 1.21 8.000 0.6557 0.6886 1.05 10.000 0.8105 0.8245 1.02 15.000 0.9490 0.9486 1.00 l 20.000 0.9814 0.9799 1.00 30.000 0.9957 0.9948 1.00 40.000 0.9985 0.9980 1.00 50.000 0.9993 0.9991 1.00 D:\\APC\\EPRI 78.296 1-9 o2/24,8
m i e Table 1-4: Effect of Inclusion of Additional Data on the Reference Leak Rate Database for 7/8" Tube APC Applications Leak Rate (lph) Log ( Leak Rate )l-Parameter Reference w/ additional Reference w/ additional Database Database Database Database Sample Size 26 27 2S 27 Sample p 13.74 13.32 0.5764 0.5696 Sample a 21.13 20.84 0.8338 0.8188 p Value W.Afi$1Mhfisd;2";*j@ier 6.5% 6.4% The following are based on the lognormal distribution sample parameters. Population p 23.91ph 22.01ph These values are biassed to Population a 149.1 lph 128.01ph be higher than expected. Upper 95% Pred. 100.61ph 92.5 lph These ranges are biassed to Lower 95% Pred. 0.143lph 0.1491ph be wider than expected. Notes: 1. It has been previously shown that a log-normal distribution can be used to describe the population ofleak rates. nuectrear vs.2es 1-10 c2tstse
Figure 1-1: Burst Pressure vs Volts for 7/8" Alloy 600 SG Tubes Additional Data, Reference o = 68.8 ksi @ 650 F r 12.0 -l ....s EPRI/NRC Database 10.0 Additional Data 1 Regression Curve N N
95%/90% Tol. Band s
8.0 N s.s o s m5 ...n' 8 K g m G0 x N N a> s u A N y .- ~. u N m 4.0 s N s .g .. _ _.-hs, 2.0 0.0 0.1 1. 10. 100. Bobbin Amplitude (Volts) nanv n, wnw n.,vi 1-11 RFK: 2/24/96. 3.24 PM
Figure 1-2: Burst Pressure for 7/8" Diameter Tubes Deviate Analysis of Additional Data [ m Observed Data 2'0 [ Normal Distribution /__ 1.5 p 1.0 > 0.5 3 / {" / = -0.5 "8 / $-,.9 / / -1.5 f a -2.0 p -2.5 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 Observed Deviate Values 1-12 RFK-2/24/96,3 23 PM nom, m. i u~ %
Figure 1-3: Burst Pressure vs Volts for 7/8" OD Alloy 600 SG Tubes NRC/EPRI Database, Reference o = 68.8 ksi@ 650 F r 12.0 EPRI/NRC Database Additional Data 10.0 Regression Curve --- 95% Prediction @ LTL + New Regression N W 8.0 : N x New 95% Pred @ LTL t~g .N d$ '*~u y% y h ')L'x m s "- m 60 g q N m A x ' n,, Q y k ~ u w h 'n. % N k 4.0 A.: _ _ _. 3.657 ksi - - ----- -~- -
~ --
s / c,, % N ,i %n -- -~. -.. - g_5gn gg; -. ..e. ...1. x, 2.0 n l d,. li ']t .-- 8.8 V - 28.5 V 0.0 O.1 1. 10. 100. Bobbin Amplitude (Volts) 1.]3 RFK: 2/24/96. 3 25 PM -o~. ~.... n. .n r a
Figure 1-4: Probability of Leak for 7/8" SG Tubes Effect ofInclusion of Additional Data 1.0 y [ EPRI/NRC Database Additional Data 0.8 f --- POL EPRI/NRC Data m E$ .7 w/ Additional Data 0 E h c jo l'l j 0.6 r )!gl j 0.5 t b 0.4 3s / g 0.3 S 0.2 ef l ? 0.1 ff 0.0 0.01 0.1 1.0 10.0 100.0 Bobbin Amplitude (Volts) 1.14 prv. onA AR 19APM
D t Figure 1-5: Leak Rate vs Bobbin Amplitude 7/8" Tube Data, All Data, NRC Correlation l 1000.0 Test Database Additional Data L - - Distribution Mean 100.0 - - - - 95% Confidence s - -Regression Exp(Q) Regression Median (Q) ,x n 2 10.0 ? '= f y N .a*** i M / m 10 A s' i e t i 0.1 l 0.01 1.0 10.0 100.0 Bobbin Amplitude (Volts) T7Arw rwr wk1 NRC Pw 1-15 arm 2/24ss. 3:27 PM -}}