ML20079N895
| ML20079N895 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 02/25/1983 |
| From: | Robert E. Uhrig FLORIDA POWER & LIGHT CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, L-83-95, NUDOCS 8303040460 | |
| Download: ML20079N895 (3) | |
Text
_ _ _ _ _ _ - _ _ _ _ _ _ _ _ _. _ _ _
P. O. BOR 14000, JURO BEACH, FL 33OO8 q
FLORIDA POWER & LIGHT COMPANY February 25, 1983 L-83-95 g
~
l 1
r1
.g G
7.Z i
N
.4O l
Mr. James P. O'Reilly ph Regional Administrator, Region II y
g,mz U.S. Nuclear Regulatory Commission d O cc in.,
101 Marietta Street, Suite 3100 Atlat.ta, Georgia 30303
,c,
,2~
g
Dear Mr. O'Reilly:
Re:
St. Lucie Unit 2 Docket No. 50-389, 10CFR50.55(e),82-002 FAN BELT PROBLEMS DURING IMITIAL START-UP OF DIESEL GENERATOR On February 10, 1982, Florida Power and Light Company notified the Region II Office of Inspection and Enforcement, in accordance with the require-ments of 10CTR50.55 (e), of a potential deficiency regarding the fan belts on diesel generators 2A and 2B.
Attached please find our final resolution of this issue.
Very truly yours, C
l Robert E. Ltrig l
Vice President Advanced. Systems and Technology 1
i be 4
8303040460 830225 y,,(7 PDR ADOCK 05000389 g
PDR PEOPLE.. SERVING PEOPLE
c_
.e
.,g I.
SUMMI.RY The diesel generator fan drive belts have experienced excessive vibration resulting in belt flapping.
Fc the requirements of 10CFR50.55(e) this concern was evaluated and has been deemed reportable. This final report is being submitted to provide NRC with a description of the deficiency and the corrective actions which have been implemented.
II DESCRIPTION The Diesel Generator System was delivered as a complete unit by the vendor, Power Systems Division of Morrison Knudsen Ing. On February 9, 1982, during l
initial startup and testing of. Diesel Generators 2A and 2B, a problem was l
identified on the diesel generator fan belts, which were flapping and twisting excessively above a speed of 700 rpm (rated speed 900 rpm).
Modifications were o
performed on the equipment and an engineering evaluation of test runs on the l
modified equipment has concluded that the Diesel Generator equipment is now acceptable for operation.
i I
III-CORRECTIVE ACTION l
l In order to address the problem, changes were implemented in belts, bearings, as well as strengthening and relocating of structural support members.
The previously used five single strand belts were replaced by one power band belt with five separate grooves, some bearings, shafts and sheaves were changed with different sized ones and structural members were added for pulley support.
These changes corrected the flapping on the 16-cylinder end of the diesel generators.
For the four (4) 12-cylinder engine fans, a system of seven (7) back side fan belt rollers have been installed around each drive belt.
The final arrangements of the Diesel Generator equipment have been tested in order to observe any possible belt flapping, generator vibration, or other unusual conditions which could have been induced by the addition of this modification. No adverse reactions were observed and the restriction of belt travel imposed by the roller resulted in acceptable operation.
Calculations that were performed by the vendor in conjunction with this modification indicated that no other additions would be necessary to safely operate with the back side rollers.
IV SAFETY IMPLICATIONS We have' evaluated this concern and determined that a deficiency in final design existed which if left uncorrected could have affected plant safety.
If the single strand belts had experienced excessive flappino, it is possible that tney could have come off the pulleys, putting the fan out of operation.
Loss of this cooling capability could impair the operation of the diesel generator and could result in loss of emergency AC power which in turn could prevent the safe shutdown of the plant following a loss of on-site and off-site AC power supplies.
Corrective action as identified above, has been implemented.
[ ---
r
,,. 4 o
i V
CONCLUSIOf1 We deem this deficiency to be reportable under the requirements of 10CPR50.55(e).
With the above mentioned corrective actions, this item is resolved and closed.
I l
_-_______-_ _ _ _ _ _ _.