ML19209A086

From kanterella
Jump to navigation Jump to search
Responds to IE Bulletin 79-15, Deep Draft Pump Deficiencies. Two safety-related Pumps Tested Monthly
ML19209A086
Person / Time
Site: Prairie Island  Xcel Energy icon.png
Issue date: 09/07/1979
From: Wachter L
NORTHERN STATES POWER CO.
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
References
NUDOCS 7910020212
Download: ML19209A086 (2)


Text

,

7K.

~

NSP COMPANY NORTHEPN STATES POWER M O N N E A PO L.l S. M O N N E S OTA 55400 September 7, 1979 .

IUnited States Nuclear Regulatory Commission Office of Inspection and Enforcement Uashington, D.C. 20555 Attention: Director, Division of Reactor Construction Inspection PRAIRIE ISL/L NUCLEAR GENERATING PLA';T Dockets No. 50-282 and No. 50-306 In response to IE Bulletin 79-15, the following is submitted:

Itcm 1 Prairic Island is equipped with two safety-related diesel driven cooling water pumps that are similar to those shown in Figures 1 and 2 of IE Bulletin 79-15.

Item 2 These pumps are designed to supply cooling wate: to the plaat in the event that normal cooling water pumps are not available. They were manufa-tured by the Wcrthington Pump Corporation. The model number is 20 QL-26. The pumps are desi;ned to deliver 13,000 CPri at a discharge head of 240 f eet.

Item 3 See the attached drawings for the overall dimensions of the pumps.

Item 4 Ecch pump was preoperationally tested during plant construction. The pur.ps are tested monthly and at other times that operability must be verified.

Preventive maintenance is performed on the pumps aad driver ajstems at six months, one year, and five year intervals. Cortective maintenance is performed on the pumps and driver systems when necessary.

The preoperational test on each pump included tests to determine the suction head available and the shutoff head delivered. The pumps were initially operated for one hour and then operational data was recorded. The operational data recorded includca suction head, discharge head, flow rates, pump speeds, bearin,o. temperatures, and vibration data. Following the one hour test, the pumps were operated for two weeks and operational data was recorded hourly.

After the two week run, each pump was started and stopped 150 times. The last test performed was to increase the flow to 17,500 GPli on each pump and then record operational data. The pumps performed as designed curing tie preoperational testing. }}h 791 0 oc o e / 7__ 6 GEP 1 .

NORTHERN STATES POWER COMPANY United States Nuclear Regulatory Commission September 7, 1979 Page 2 Each pump is tested monthly to verify operability. The pumps are run for o - minimum of one-half hour and then operational data is recorded. The pump flow rate and discharge head are compared to the pump curve to verify

     ; operability. The pumps are also tested when conditions prescribed in the
      -Prairie Island Technical Specifications require that operability be verified. A review of the tests performed to date revealed that the pumps have always performed as designed.

Preventive maintenance is performed on the pumps and driver systems at six month, one year, and five year intervals. At six month intervals, the pump bearing lubricating water supply system is cleaned. At one year intervals, the pump tubing te"sion bearing clearance is checked and the bearing is cleaned. All o%et preventive maintenance is performed on the driver system. Item 5 Nc significant operational problems have been enccuntered with the Worthington Pumps, and rm major maintenance has been performed on the pumps. Corrective maintenance has been limited to cleaning of the pump bearing lubricating system. Item 6 No corrective reaintenance has been performed on the pumps that has af f ected the operability of the pumps since preoperational sting was completed in October, 1973. The 12 and 22 Diesel Driven Cooling Water Pumps have been run at least 113 and 99 times, respectively, since October,1973. Each run was for a minimum of one-half hour at near rated flow. The longest continuous operation at or near rated flow was the two-week test run conducted during preoperational testing. Both pumps were operable at the completion of the test. Yours very truly, fY  : L. J. Wachter Vice President - Power Production and Sv;. , Operation cc: Mr. G. Charnoff (w/9 enclosure)

4. J.mes G. Keppler (w/o enclosure) -

Enclosure}}