ML20151R094
| ML20151R094 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 08/01/1988 |
| From: | Withers B WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| WM-88-0178, WM-88-178, NUDOCS 8808120050 | |
| Download: ML20151R094 (3) | |
Text
_.
o WQLF CREEK NUCLEAR OPERATING CORPORATION August 1, 1988
,,n oy,%
President and CW Esec*e Omcer WM 88-0178 U. S. Nuclear Regulatory Commission ATTN Document Control Desk Hall Station PI-137 Washington, D. C. 20555
Subject:
Docket No. 50-482: Pump and Valve Inservice Testing Program Relief Request Centlemen:
The purpose of this letter is to transmit relief request PR-14 for the Wolf Creek Generating Station Inservice Testing Program in accordance with 10 CFR 50.55a(g)(5)(iii).
This request concerns the ASME code requirement for the measured or observed and recorded bearing temperature for the Safety Injection Pumps. The details of the relief request have been discussed with Mr.
Paul O'Connor and other members of the Nuclear Regulatory Commission Staff.
3 Enclosed is a check (No.
1946) for the $150.00 application fee required by 10 CFR 170.21.
If you have any questions concerning this matter, please contact me or Mr. O. L. Maynard of my staff.
Very truly yours, Bart D. Withers President and Chief Executive Officer BDW/jad Attachment Enclosure cc:
B. L. Bartlett (NRC), w/a D. D. Chamberlain (NRC), w/a R. D. Martin (NRC), w/a T. K. McLellan ( NRC), w/a hg&
P. W. O'Connor (NRC), w/a (2) 1 I
kkV*
PO. Box 411/ Burhngton, KS 66839 / Phone: (316) 364-8831 g) f$0*$0000$$$$8je2
^ " ' * " " " ' ' " ' ' ' * * ' ' * ' " " " " ' '
PDC.
a s
s Attachment to WM 88-0178 j
Page 1 of 2 l
RELIEF REQUEST NO. PR-14 PUMPS:
PEM01A and B, Safety Injection Pumps CLASS:
ISI Class 2 TEST REQUIREMENT:
Bearing temperature shall be measured or observed and recorded (lWP-3100).
The temperature of all centrifugal pump bearings outside the main flowpath shall be measured at points selected to be responsive to changes in the temperature of the bearing (IWP-4310).
BASIS FOR RELIEF:
a) Under normal operating conditions the only run time for the Safety Inj ec tion ( SI) Pumps is during the quarterly surveillance test.
This test runs the pump near its shutof f head with only 45 gpm miniflow.
The test du ation is approximately 15 m inu te s.
Paragraph IWP-3500 requires the pump be run until the bearing temperatures stabilize.
Bearing temperatures are considered stabilized when three successive readings taken at 10 minute intervals do not vary by more than 3 percent.
This process of measuring bearing temperatures would take approximately one hour.
As part of the actions required by NRC Bulletin 88-04, "Potential Sa fety-Rela ted Pump Loss", the pump vendor was contacted to verify that current miniflow rates are suf ficient to ensure that there will be no pump damage from low flow operation.
The vendor indicated that the pump may be run on the present minimum flow of period of time not to exceed 30 minutes with no 45 gpm fo r a noticeable degradation of pump performance.
b) The bearing temperature cannot be measured direc tly.
Measuring the temperature of the oil leaving the bearing is the only practical way to determine bearing temperature. The oil is cooled by component cooling water ( CCW) which is cooled by service 0
0 water.
The temperature of CCW varies from 70 F to 100 F from winter to summer.
The re f ore,
the oil temperature entering the j
bearing varies with the season.
(
s=
Attachment to kN 88-0178 Page 2 of ':
c) Bearing temperature t:sken at one-year intervals in accordance with IWP-3300 provide little data toward de te rmining the incremental degradation of a bearing or prov id ing any meaning ful trend in forma t ion.
d) The SI pumps are tested for vibration on a quarterly basis in accordance with IWP-4500.
Vibration measurements are a l
significantly more reliable indication of pump bearing degradation than bearing temperature measurements.
In summary, other measurable parameters are more indicative of pump performance and running the pump at low flows may actually be detrimental to pump performance.
ALTERNATE TESTING:
None
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _