IE Circular No. 79-19 - Loose Locking Device on Ingersoll-Rand Pumps
CR79019 September 10, 1979 MEMORANDUM FOR: B. H. Grier, Director, Region I J. P. O'Reilly, Director, Region II J. G. Keppler, Director, Region III K. V. Seyfrit, Director, Region IV R. H. Engelken, Director, Region V FROM: Norman C. Moseley, Director, Division of Reactor Operations Inspection, IE SUBJECT: IE CIRCULAR No. 79-19 - LOOSE LOCKING DEVICE ON INGERSOLL-RAND PUMPS The subject Circular is transmitted for issuance on September 13, 1979. The Circular should be issued to all power reactor operating facilities and all utilities having a construction permit. The text of the Circular and draft letter to the licensees and permit holders are enclosed for this purpose. Norman C. Moseley, Director Division of Reactor Operations Inspection Office of Inspection and Enforcement Enclosure: 1. Draft Transmittal Letter 2. IE Circular No. 79-19 CONTACT: H. A. Wilber, TP 49-28180 . (Draft transmittal letter for IE Circular No. 79-19, to each holder of an Operating License or a Construction Permit.) IE Circular No. 79-19 Addressee: The enclosed IE Circular No. 79-19, is forwarded to you for information. No written response is required. Should you have any questions related to your understanding of this matter, please contact this office. Sincerely, Signature (Regional Director) Enclosures: 1. IE Circular No. 79-19 2. List of IE Circulars Issued in the Last 6 Months . SSINS: 6830 Accession No: 7908220111 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 September 13, 1979 IE Circular No. 79-19 LOOSE LOCKING DEVICES ON INGERSOLL-RAND PUMP IMPELLERS Description of Circumstances: Three reports have been submitted to the NRC regarding the loosening of locking devices on the impellers of pumps manufactured by the Ingersoll-Rand Company. The first report was submitted as a significant deficiency (10 CFR 50.55[e]) by Arkansas Power and Light Company in letters of March 17, 1978 and May 9, 1978. The licensee reported excessive noise and vibrations in both Low Pressure Safety Injection (LPSI) pumps during the preoperational test program on Unit 2 of Arkansas Nuclear One (ANO). It was discovered that the washers, jam nut and cap nut used to retain the impellers were missing on both pumps (Ingersoll-Rand Type 8X20WD). The licensee's corrective action involved the installation of a tab washer. This corrective action was, also, taken on the containment spray pumps (Ingersoll-Rand Type 6X23WD) because of similarity of design. The second report was submitted by Duke Power Company in a licensee event report (LER 50-287/78-23) dated January 24, 1979. The symptoms were similar to those observed at ANO Unit 2 in that high vibration was detected in a reactor building spray pump (Ingersoll-Rand Type 4X11A) for Oconee Unit No. 3. The licensee found that the impeller had worked loose. The corrective action included a revision to the maintenance procedure to specify torque requirements. The third report was 10 CFR 21 Report No. 79-01 submitted by Portland General Electric Co. on April 16, 1979. This report identified a deficiency that may exist in the Trojan Nuclear Plant containment spray pumps (Ingersoll-Rand Type 6X23WD) in that there is a potential for the impeller lock nut to loosen. The potential deficiency was identified because of the similarity of the containment spray pumps design to the residual heat removal (RHR) pumps (Ingersoll-Rand Type 8X20WD) and the discovery of a loose lock nut on an RHR pump during pump maintenance. The corrective action was to provide a positive mechanical lock on the impeller nut. Westinghouse Nuclear Service Division has issued a Technical Bulletin to Westinghouse plant owners on loose lock nuts on Ingersoll-Rand Types W, WD, and WDF pumps. Excerpts from that Technical Bulletin are in Enclosure No. 1. Combustion Engineering, Inc. has, also, informed the NRC of their actions relative to the same problem in a letter dated March 13, 1978; excerpts from this letter are in Enclosure No. 2. . IE Circular No. 79-19 September 13, 1979 Page 2 of 2 Recommended Action for Licensee's Consideration All holders of operating licenses and construction permits should be aware of the potential deficiency described above. It is recommended that the licensees review the pumps used or planned for use in safety related systems at their facilities to determine if Ingersoll-Rand Types A, W, WD, WDF are installed. If these pumps, or units with similar impeller locking systems, are used, the licensees should determine that the impellers are presently locked in an acceptable manner and that maintenance and installation instructions provide adequate guidance to ensure that pump impellers are securely locked in place. No written response to this Circular is required. If you need additional information regarding this subject, please contact the Director of the appropriate NRC Regional Office. Enclosure No. 1: Excerpt from Westinghouse NSD Technical Bulletin No. NSD-TB-78-3 Enclosure No. 2: Excerpt from Combustion Engineering Inc. Letter to Nuclear Regulatory Commission, March 13, 1978 . Enclosure No. 1 EXCERPT FROM WESTINGHOUSE NUCLEAR SERVICE DIVISION TECHNICAL BULLETIN No. NSD-TB-78-3 April 21, 1978 Several plants under construction have experienced a loosening of the impeller lock-nut on the Ingersoll Rand RHR Pumps. The problem has occurred during the initial startup of the pump or during flushing operations. The possible causes for this lock nut becoming loose could include: running the pumps in reverse rotation, improper torquing of the lock nut, or the effects of foreign materials in the pumped fluids which could cause binding of the impeller. Westinghouse, in conjunction with the supplier, has developed retrofit kits. These kits may be provided as an alternate method to further assure a more positive locking mechanism than that originally furnished with the pump. *Quantity & Model 8 X 20 W - (2) PNJ, PGE, PEG, AMP. Quantity & Model 8 X 20 WD - (2) TVA, TEN, VGB, VRA, DAP, DBP, APR. Quantity & Model 8 X 20 WDF - (2) WAT, WBT, CGE, CQL, CRL, CSL, CTL, NEU, DMW, TBX, TCX, CAE, CBE, CCE, CDE, DCP, DDP, NAH, NCH, LLP, LMP, GAE, GBE, PBJ, PCJ. . Dr. Ernst Volgenau - 2 - Millstone Unit II is currently shutdown for refueling and maintenance; the earliest initial operation of either Waterford Unit 3 or San Onofre Units 2 and 3 pumps is expected in late 1979. In our opinion no condition currently exists which adversely affects the health and safety of the public. Arkansas Power and Light has committed to provide the Nuclear Regulatory Commission a detailed report of the pump failures and their intended corrective action. Combustion Engineering, in conjunction with Ingersoll-Rand, is supporting that effort. Ingersoll-Rand has modification kits available which provide a more positive locking design. Combustion Engineering is recommending prompt installation of these modification kits on ANO-2 and Millstone II. We are recommending to Louisiana Power and Light and Southern California Edison that the modification kits be installed prior to initial operation of their pumps. Very truly yours, COMBUSTION ENGINEERING, INC. . Enclosure No. 2 Excerpts from Combustion Engineering Inc. Letter to the Nuclear Regulatory Commission March 13, 1978 LD-78-019 Dr. Ernest Volgenau, Director Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Dear Dr. Volgenau: This is to confirm my telephone conversation with Mr. Davis of your office on March 10, 1978. On February 17, 1978 Arkansas Power and Light reported to Mr. Jim Gagliardo, NRC Region IV, the successive failures of the two Low Pressure Safety Injection Pumps' impeller retaining parts at the initiation of shutdown cooling during PreOperational testing at ANO-2. That report was made pursuant to the provisions of 10 CFR 50.55(e). Since that time, Combustion Engineering has investigated whether similarly designed pumps (Ingersoll-Rand WD & WDF models) have been supplied by C-E to other nuclear facilities. We have determined that four other Combustion Engineering supplied Nuclear Steam Supply Systems have this type of impeller locking system on their Ingersoll-Rand pumps and may be susceptible to this type of failure. They are Northeast Utilities' Millstone Unit II, Louisiana Power and Light's Waterford Unit 3 and Southern California Edison's San Onofre Units 2 and 3.
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