ML20127N163
| ML20127N163 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 11/18/1992 |
| From: | Link B WISCONSIN ELECTRIC POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CON-NRC-92-136 VPNPD-92-356, NUDOCS 9212010023 | |
| Download: ML20127N163 (4) | |
Text
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f Wisconsin Electnc POWER COMPANY 231 w Menon ro b 2a46.wxAeo n 53201 p sj22t 2345 VFNPD 35 6 NRC 136 November 18, 1992 Document Control Desk U.S.
NUCLEAR REGULATORY COMMISSION Mail Station P1-137 Wathington, DC 20555 Gentlemen:
DOCKET 50-301 ASME SECTION XI RELIEF REQUEST RF-2-15 POINT BEACH NUCLEAR PLANT, UNIT 2 In accordance with 10 CFR 60.55a(g) (5) (iv), Wisconsin Electric Power Company requests relief from Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, " Rules for Inservice Examination of Nuclear Power Plant components," 1986 edition, no addenda.
The requirements for which relief is requested apply to the third inservice inspection interval for Point Beach Nuclear Plant,-Unit 2.
This interval is scheduled to begin in Decembar 1992.
The attached relief request, RR-2-15, provides the information i
needed for the NRC to complete a review and approval as required.
Sincerely, 3
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,f Bob Link Vice President Nuclear Power 39 Attachment cc:
NRC Regional Administrator NRC Resident Inspector 9212010023 921110 A
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ASME SECTION XI RELIEF RECitEST RR-2-15 j
FOR THIRD INSERVICE INSPECTION INTERVAL j.
POINT BEACH NUCLEAR PLANT, UNIT 2 i
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COMPONENT l
Reactor Vessel ASME SECTION XI REOUIREMENT i
i TABLE IWB-2500-1, EXAMINATION CATEGORY B-D l
Item No. B3.90 Reactor Vessel Nozzle-to-Vessel Welds
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l Item No. B3.100 Reactor Vessel Nozzle Inride Radius Section l
Note 2 At least 25 percent, but not more than j
50 percent (credited), of the nozzles shall j
be exemined by the end of the first inspection period, and the remainder by the i
end of the inspect!on period.
TABLE IWB-2600-1, EXAMINATION CATEGORY B-A Item No. Bl.30 Reactor Vessel Shell-to-Flange Weld i
Note 6 The examination of shell-to-flange welds may l
be performed during the first and third inspection periods in conjunction with the nozzle exardnations of Exam. Cat. B-D i
(Program B).
At least 50 percent of shell-l to-flange welds shall be examined by the end j
of_the first inspection period, and the
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i remainder by the end of the third inspection period.
l ALTERNATE REOUIREMENT i
i The proposed alternate examination is to perform essentially all of Item Nos. B3.90, B3.100, and Bl.30 by the end of the interval in conjunction with the 10-year' Reactor Vessel' Examination,-whict.
1 is currently scheduled in 1998.
This relief request is for the deferral, not the exemption, of code examination requirements of Category B-D and B-A welds.
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l REASON FOR PROPOSED ALTERNATE EXAMINATION The Point Beach Nuclear Plant (PBNP) Unit 2 Reactor Vessel has six nozzles.
They consist of two inlet nozzles, two outlet i
nozzles, and two safety injection (SI) nozzles.
During the second 10-year interval, the two outlet nozzles and their asso-ciated inside radius section were examined in the fall of 1984 a
(second outage of the first period) meeting the requirements of Note 2 for Category B-D welds.
In 1989 (first outage of the third period), a complete reactor vessiti examination was per-formed including the outlet nozzles examined in 1984.
No indications were found that exceeded the ASME Section XI Code acceptance criteria.
In order to meet the requirements of Note 2 (Examination Category B-D), two of these nozzles are required to be examined i
during the first period of the third 10-year interval.
- However, this is considered undesirable for the following reasons:
1 1.
Note 3 of Table IWB-2500-1 (Examination Category B-D) allows partial deferral of the nozzle examinations if the examina-tions are conducted from inside the component and the nozzle weld is examined by straight beam ultrasonic method from the nozzle bore.
Examination from the nozzle bore and nozzle inside radius examinations can be performed only on the outlet nozzles without removal of the core barrel.
There-fore, the outlet nozzle exam becomes a one-sided exam from the inside nozzle.
The remaining exam of the nozzles from the vessel side is completed concurrent with the 10-year reactor vessel examination.
By deferring the nozzle exam to be performed concurrent with the 10-year reactor vessel exam, the correlation of the data obtained will be more technically sound.
i 2.
This examination is performed utilizing vendors with automated inspection equipment.
Examination of all welds at the same time will ensare the same vendor, personnel, procedures, and equipment are utilized resulting in more cor.sistent and comparable results among the nozzles.
3.
The inspection equipment used for automated examination is a large device (approximately 2,275 lbs) that is lowered onto the reactor vessel.
By performing all examinations at one time in the interval, the probability of a handling accident of the examination device is reduced.
4.
The cost of performing an examination of the reactor vessel outlet nozzles (without core barrel removal) is l
approximately $400,000 (1992 dollars).
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An estimated 2 man-rem of radiation exposure is expected to i
perform this examination along with the associated radwaste.
i 6.
Examination of all the reactor vessul nozzles aha their l
associated inside radius section and the reactor vessel shell-to-flange weld was recently conducted during two 1989 reactor vessel examination with no indications that exceeded i
the code allowable limits.
The examination was performed 1
in accordance with the 1977 Edition up to and including i
the summer of 1979 addenda of ASME XI and Regulatory j
Guide 1.150, Rev.
1.
Examination of the reactor vessel shell-to-flange weld 1
(in accordance with Note 6, Examination Category B-A) is i
normally performed with the automated inspection equipment used to examine the reactor vessel nozzles (Examination Category B-D).
l It is possible to examine thia weld with manual ultrasonic j
techniques; however, due to the close proximity of the reactor vessel to the examiner, the radiation dose received is a
i considerable (0.5-1.0 man-rem).
It is preferred to perform this exar.ination using the automated inspection equipment l
concurrent with the 10-year reactor vessel exam because of l
cost and ALARA concerns.
i Based on these reasons, it is requested that the examination requirements for Examination Category B-D and B-A be deferred i
i until the end of the interval and be performed in conjunction with the 10-year reactor vessel examination which is currently l
scheluled for 1998, i
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