ML20058K982

Application for Amend to OL Application Re Proposed Mods to Sensitized Stainless Components Attached to Plant Nuclear Pressure Vessel

ML20058K982
Person / Time
Site:	Monticello
Issue date:	05/07/1970
From:	Mcelroy D NORTHERN STATES POWER CO.
To:
Shared Package
ML20058K441	List: ML20058K439 ML20058K982
References
NUDOCS 9105070334
Download: ML20058K982 (5)

Text

. _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _. _ - _ _ _ _ _

O O

. >. 1,,

i Regulatory File Cy.

\\

~

UNITED STATES ATOMIC ENERGY COMMISSION 88"i<ad wMr we3 MO i

t

,,l NORTHERN STATES POWER COMPANY l*

Monticello Nuclear Generating Plant. E-5979 Docket Number 50-263 1

't s-AMENDMENT NO. 26 5

'lV t

i' APPLICATION FOR AEC CLASS 104b OPERATING il LICENSE FOR A UTILIZATION FACILITY l

s l1 l;

!1 Northern States Power Company, a corporation organized under the laws of the State of Minnesota, applicant for an operating 4

j license for the Monticello Nuclear Generating Plant, hereby amends its application by submission of Amendment 26.

Amendment 26 describes our proposed modifications to sensi-tized stainless components attached to the Monticello nuclear pres-I-

sure vessel.

i i

t i

a I

6 j.-

CF 9105070334 700507 R

ADOCK 05000263ifj j

CF ;y W.

l

O 1 This Amndent to the application contains no restricted or i

other defense information.

4 Dated May 7, 1970 NORTHERN STATES POWER COMPANY D

f By

.L 7

h D. F. McElmy 1

=-,

- -=.

e.

O O

t STATE OF MINNESOTA)

COUNTY OF HENNEPIN) f!

}

D. F. McElroy, being first duly swom, says that he is the Vice President-Engineering of Northern States Power. Company, a corporation organized and existing under and oy virtue of laws l

of the State of Minnesota, that he executed the foregoing appli-cation for amendment for the purpose therein set forth; that the l

statements made in said application for amendment are true and-correct to the best of his knowledge and belief; that he was l

- authorized.to execute said application on behalf of said corpo-ration; and that the seal affixed is the corporate seal of said f

I corporation.

I l

.n_.

D. F. McElroy Subscribed and sworn to before me This day of May

,1970 l:

I/

i Robert E. Hessian Notary Public, llennepin County, Minnesota-l l

My Commission Expires May 15, 1976

\\

i i

8. *,

l i

.w-.m

+-+yqr g-

-*p,-

-v3-e a

wqew-pg

• -p-p e

tr g e-er C+t-'

T

~

~

^

~

O v

..d AEC Docket No. 50-263 A

4 M/d S 1970 ~ C Regulatory File Cy.

A!ENDMENT 26 8

Receivsd w/ Lit Calad IY"[O N

! #h i l-4 This amendment describes propueed modifications to the furnace sensitized stainless steel l

components attached to the reactor pressure vessel. Table 1 lists the components and aummarizes the type of modifications. A description of the types of modifications follova Table 1.

TABLE 1

)

Proposed Component Spec. - Grade - & Condition Modification j

HlA & N1B Recirculation Outlet SA240-Tp30h - Solution heat treated Clad ID only Nozzles Safe End Rolled and Welded Furnace Sensitized N6A & N6B Top Head Instru-SA182-F3Oh - Solution heat treated Replace mentation Furnace Sensitized Long veld neck flange NT Top Head Vent SA182-F304 - Solution heat treated Replace Long veld neck flange Furnace Sensitized N8A & N8B Jet Pump Instrumentation SA336-F8

- Solution heat treated Replace Nozzle Safe End Furnace Sencitized N9 CRD Hydraulic S' stem SA336-F8

- Solution heat treated Replace y

Return Nozzle Safe Furnace Sensitized End j

20 Weld buildup of SA298 Type 308 - Weld metal overlay existing Jet Pamp mounting pads Furnace Sensitized mounting pads and attachment velds l

32 various sizes - veld build-SA298 Type 308 Weld metal overlay Pad and l

up of mounting pads Furnace Sensitized attachment veld ;

i Description of Modifications i

Replacement of Furnace Sensitized Stainless Nozzle Safe Ends and Long Weld Neck Flanges -

j Safe ends for nozzles NdA, NdB, & N9, and long veld neck flanges for N6A, N6B, & NT, vill be removed by machinin6 in a manner such that the veld buttering on the ferritic nozzles vill not be disturbed.

J Replacement safe ends are SA336-F8 forgings. Safe ends for N8A and N8B are each comprised-of two half section forgings requiring two longitudinal velds. All replacement' safe ends" ;

j l

meet quality control requirements equal to those required in the original fabrication, i.e.,

i j

USAS1 B31.1.0 upgraded to meet ASME Section 3 requirements in regards to materials, velding, non-destructive examinations and documentation thereof.

1 1400 1

All velds vill be liquid penetrant examined and radiographed. In addition, a new baseline I

examination,which vill be used as a reference for future inservice examinations, vill be l

performed utilizing ultrasonic testing methods.

l

]

Cladding of Recirculation Outlet Nozzle Safe Ends - Safe ends for recirculation outlet nozzles 1

NlA and N1B will be clad on the inside with SA295 - Type 308L. The inner circumference of

'l

-tha safe end is marked in 9CP segments. These provide' reference lines for the velder'to follow in depositing his initial veld bead in each quadrant. Sequencing is such that; _

i longitudinal beads are deposited in groups of four in alternating quadrants to maintain minimum interpass temperatures. Each veld bead is approximately 10}" long and covers the j

entire safe end plus an overlap of the sensitized buttering on the ferritic nozzles and the primary coolant piping.

t t

Liquid penetrant examinations using fluorescent penetrants vill.be performed both before j

and '.fter veld overlaying. Any indications discovered as a result of the liquid penetrant examinations vill be removed.

Cladding of the O.D. surfaces of these safe ends is not planned until such time there is I

l reasonable assurance that this overlay would not interfere with future inservice ultrasonic examinations. These outer surfaces vill be cleaned and liquid penetrant examined. Another l

baseline inspection vill be performed using ultrasonic methods. This baseline vill be used as a reference for future examinations.

J Overlay of Mounting pads - The existing mounting pads and attachment velds which are i

j identified below, vill be overlay clad with SA298 Type 308L.

t 20 Jet pump mounting pads

,, i 4

Steam dryer hold down pads d

4 Steam dryer support pads l

j 2

Guide rod pads i

4 8

Feedvater sparger line pads 8

Core spray piping pads

(

6 Surveillance sample holder pads a!

Additional bracing for each of the 10 jet pump risers vill be installed. The bracing material f

is Type 304. Twenty new mounting pads and attachment velas vill be SA298 Type 308L..

All veld surfaces vill be liquid penetrant examined both before and after veld overlaying.

{

Any indications discovered as a result of the liquid penetrant examinations vill be removed.

Jet Pump Replacement Castings - Spare non-carburized jet pump castings have been delivered.

I-and vill be installed during the afore mentioned modification program.

A j_

r M -r 4 yhg p

p 2.

, r+ 4,.

I g

9$

N

~

)

.