ML20215L535

Part 21 Rept Re Discrepancy Between as-tested NPSH Curve & NPSH Curve Provided by B&W,Canada for Spare Decay Heat Pump. Anomalies Detected in Test Curve Caused by Excessive Clearances.Region V Notified of Discrepancy on 870424

ML20215L535
Person / Time
Site:	Rancho Seco
Issue date:	04/29/1987
From:	Julie Ward SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
REF-PT21-87, REF-PT21-87-094-000 JEW-87-669, PT21-87-094-000, PT21-87-94, NUDOCS 8705120276
Download: ML20215L535 (2)

Text

.. -

l esuun

~

SACRAMENTO MUNICIP AL UTIUTY DISTRICT O P. o. Box 15830, Sacramento CA r S5852-1830. (916) 452-3211 AN ELECTRIC SYSTEM SERVING-THE. HEART OF CALIFORNIA

~ .

i JEW 87-669  !: S.

n.

J. B. Martin Regional Administrator Region V Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596 Docket No. 50-312 Rancho Seco Nuclear Generating Station Unit #1 License No. DPR-54 10 CFR 21 REPORT No. 06, DISCREPANCY BETWEEN AS-TESTED NPSH CURVE AND NPSH CURVE PROVIDED BY B&W, CANADA FOR SPARE DECAY HEAT PUMP

Dear Mr. Martin:

In accordance with 10 CFR 21.21(b) (2), the Sacramento Municipal Utility District hereby submits a written report documenting the notification made by Mr. R. Colombo of the District to Mr. L. Miller of Region V Nuclear Regulatory Commission (NRC) on April 24, 1987.

The notification concerns the discrepancy between the B&W Pump Curve #7133-5009 and the as-tested Pump Curve #PO933-1 & 2 supplied by Bingham-Willamette, Pump Division, Portland, Or.

Bingham-Willamette was contracted to test a spare Decay Heat Pump (Mfg: B&W, Canada, Model #KSMK 10x12x21) purchased from Midland. The Decay Heat Pump was set up and tested on March 4, 1987, in accordance with SMUD contract Specification B-472 and Bingham Standard Pump Testing Procedure #E30.39. The results of the pump performance test (Test Curve #PO933-1) confirmed the B&W '

Pump Curve #7133-5009 in regards to Total Developed Head (TDH),

Capacity (GPM), Brake Horsepower (BHP) and Efficiency (%).

However, the Net Positive Suction Head (NPSH) versus Capacity test revealed that a considerable discrepancy exists between the as-tested NPSH vs. Capacity curve #PO933-1 & 2 and that supplied by B&W (Midland) #7133-5009.

8705120276 B70429 PDR ADOCK 05000312 1 S PDR g DISTRICT HEADQUARTERS O 6201 S Street, Sacramento CA 95817-1899 g-//

1

• Y ' -

s -

- J B MARTIN JEW 87-669 Upon receipt of the. Bingham-Willamette test'results by the SMUD

- Quality Assurance Department, an internal Occurrence Description Report (ODR).was initiated requesting.the Plant Review Committee (PRC) to evaluate the test results for reportability under 10 CFR 21 regulations. In a meeting held April 17, 1987, the.PRC recommended a 10 CFR.21 Report be made. The NPSH discrepancy is being reported pursuant to 10 CFR 21.3 (d) (1) since there may not have been adequate NPSH available to the pump, had it been installed..

! Bingham-Willamette indicated that the anomalies detec ted in the test' curve are the results of two(2) problems:

b ~ a) Excessive. clearances between the Impeller Wear Rings and the Casing Wear Rings.

b) Excessive clearances between the Suction Piece / Stuffing

' box fit in the Pump Case.

The above excessive clearances are causing extreme " Jetting" against the flow into the Impeller Eye. In addition, the pump is l

running out further on its curve due to excessive recirculation,

.thus compounding the problem.

The~ spare Decay-Heat Pump will not be placed into. service until I

modifications.are performed to improve pump NPSH and efficiency with acceptable test results from Bingham-Willamette.

l If there are any questions concerning this report, please contact Mr. Ron Colombo at (916) 452-3211, extension 4236.

Sincerel

! . Ward uty General Manager, Nuclear cc: A. D'Angelo G.'Kalman c

J. Taylor (3)

' INPO l-