ML20215L326
| ML20215L326 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 10/21/1986 |
| From: | Allen C COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 2293K, NUDOCS 8610280580 | |
| Download: ML20215L326 (5) | |
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T Commonwealth Edison
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-i % One Fir;t National Plaza. Chicago, Illinois
( ~
/ Address Reply to: Post Office Box 767
%/ Chicago, Illinois 60690 - 0767 October 21, 1986 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
LaSalle County Station Units 1 and 2 SOR Differential Pressure Switches NRC Docket Nos. 50-373 and 50-374 Reference (a): September 12, 1986 letter from C. M. Allen to H. R. Denton
Dear Mr. Denton:
The letter addresses commitments made in Reference (a). These commitments relate to the disassembly and inspection of SOR differential pressure switches found unacceptable for use at LaSalle County Station (LSCS).
The Static "O" Ring report on the switches in question is attached.
The switches were pressure tested, leak tested, disassembled and all components inspected and measured.
In addition, to alleviate concerns that coolant might be leaking along the shaft past the "O" ring an extremely sensitive test was performed using a halogen detector for "O"
rings leakage.
This test indicated no leakage.
Test conclusions are as follows: 1) there is no leakage along the shaft bypassing the "O" ring; (2) discoloration on switch components is from an external source; (3) no cause of either the unacceptable setpoint shift upon pressurization or the repeatability problem can be determined from this inspection.
If you or your staff have any additional questions regarding this issue, please address them to this office.
Ve truly yours, C. M. Allen Nuclear Licensing Administrator 1m Attachment cc:
G. Wright - Region III Dr. A. Bournia - NRR Resident Inspector - LSCS (0
0 1
8610280580 861021 2293K PDR ADOCK 05000373 p
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x a
SOR. INC.
October 13, 1986 Mr. Everett Spitzner Maintenance Staff Assistant COMMONWEALTH EDISON COMPANY P.O. Box 767, Room 1230 Edison Chicago, IL 60690
SUBJECT:
SOR MODEL 103 DELTA-P SWITCHES S/ N 86-6-2513 (SPARE) 103AS-B212 S/N 85-1-2369 (NO24B) 103 AS-B212 S/N 85-1-2373 (NO24D) 103AS-B212 S/N 85-1-2375 (NO38A) 103AS-B212 S/N 85-4-260 (NOO7AA) 103AS-B203 S/N 85-1-2427 (NO13BB) 103 AS-B203 S/N 85-1-2435 (NO12BB) 103 AS-B203 S/N 86-6-2508 (SPARE) 103AS-B212
Dear Mr. Spitzner:
This report is to summarize the results of the factory disassembly and inspection of the above listed Delta-P switches.
Our incoming calibration check indicates that six of the switches were good performers, and two of the switches were bad performers.
Switch No. NO38A exhibited a 7.5 inch W.C. downward first to second cycle shift and a 7.5 inch downward static shift from zero to 1000 psi.
Switch No. NO13BB shifted upward 11.8 inches W.C. at 1000 psi static pressure.
The other six switches were within 1.0 inch W.C. when tested with the same procedure used on NO38A and NO13BB.
No rust was found in any of the bearings and no moisture was evident in any of the switch or spring housings.
The internal components were measured and no parts were found out of tolerance. We found nothing to indicate bad switch performance.
As you witnessed on 9/23/86, the cross shaft 0-rings were subjected to a halogen leak test 0 1000 psi.
The halogen leak detector (Inficon HLD 3000) was calibrated for a leak rate of 0.1 OZ/YR using 96% nitrogen and 4% freon 12.
All cross shaft o-rings exhibited 0% leakage.
PO OCX 591.11703 OLACKBOB ACAD. OLATHE. K ANSAS 66061. 913 764 2630. THE GAEATEA KANSAS CITY AREA CABLE SCA INC TELEX 42 6130 SCA iNC Static O* Acg CONTAOL CEVICES iNTE ANATIONAL TELEX NUM8EA 499-2783 SCA UI
Page 2 October 13, 1986 The following matrix summarizes our findings.
Since no oxides were detected in the bearings, it is becoming evident that the brown foreign substance is coming from an external source (all wetted metals in the Series 103 Delta-P are stainless steel).
You will note that two switches did not have loctite on the switch cover gasket and one of these had only.001 off travel.
The absence of loctite is not detrimental to switch performance and the switch with.001 off travel was one of the good performers.
The adjusting screw has been added to the 100% inspection list to eliminate the burr problem.
If you require additional data, please call.
- Regards, Way e Priest Chief Design Engineer WP:ms 100186-01 Attachment I
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86-6-2513 85-1-2369 85-1-2373 85-1-2375 85-4-260 85-1-2427 85-1-2435 86-6-2508 i
Switch ID SPARE NO24B NO24D NO38A NOO7AA NO13BB NO12BB SPARE 4
i Model No.
103AS 103AS 103AS 103AS 103AS 103AS 103AS 103AS B212 B212 B212 B212 B203 B203 8203 B212 Inst' lled 3/85 X
X a
Installed but not pressurized by reactor X
X X
X Not installed X
X SQt Point as received 67.6" 63.1" 64.6" 75.6" 116.2" 166.6" 150.9" 62.4" 1st to 2nd cycle shift 0 0 psi
-0.7"
-0.3"
-0.5"
-7.5"
-0.3"
-0.4"
-0.6"
-0.4" 1st to 2nd cycle shift 81000 psi
-0.4"
-0.3"
-0.0"
-0.4"
-0.4"
-0.6"
-0.5"
-0.3" Static shift 0 to 1000 psi
-0.7"
+1.0"
-0.6"
-7.5"
-0.5"
+11.8"
-0.8"
+0.9" Off travel at microswitch
.0055
.004
.007
.005
.009
.009
.010
.001 Burr on adjusting screw No Yes Yes Yes Slight Yes Yes No Halogen Leak Test 0.1 OZ/YR 01000 psi 0%
0%
0%
0%
0%
0%
0%
0%
Lo Pressure Body O-Ring Extrusion Mild None None None None None None Mild Hi Pressure Body 0-Ring Extrusion Severe None None None Mild None Mild Moderate Loctite on Switch Cover Gasket No Yes Yes Yes Yes Yes-Yes No Brown Deposit on Cross Shaft on Spring Side No No No Trace Trace No Moderate No Brown Deposit on Cross Shaft on 1
Switch Side No No No Moderate Trace No Moderate No Brown Deposit on 011 (Dynamic) 0-Ring on Spring Side No No No No No No No No Brown Deposit on 011 (Dynamic) 0-Ring on Switch Side No No No No No No No No i
86-6-2513 85-1-2369 85-1-2373 85-1-2375 85-4-260 85-1-2427 85-1-2435 86-6-2508 Brown Deposit on 012 (Static)
O-Ring on Spring Side No No No No No No Moderate No Brown Deposit on 012 (Static)
O-Ring on Switch Side No No No Trace Trace Trace No No Brown Deposit on Vacuum Protector on Spring Side No No No No No No Moderate No Brown Deposit on Vacuum Protector on Switch Side No No No No No No No No Brown Deposit on Lo Pressure Body Cavity No No Trace No Trace No Moderate No Brown Deposit on Hi Pressure Body Cavity No No No No Trace No Trace No
.