IE Circular No. 79-19 - Loose Locking Device on Ingersoll-Rand Pumps


                            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 

                    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 
                                   Office of Inspection and Enforcement 

1.   Draft Transmittal Letter 
2.   IE Circular No. 79-19 

CONTACT:  H. A. Wilber, TP 

(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 


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. 


                                        (Regional Director) 

1.   IE Circular No. 79-19 
2.   List of IE Circulars Issued 
       in the Last 6 Months 

                                                      SSINS:  6830 
                                                       Accession No: 

                              UNITED STATES 
                          WASHINGTON, D.C.  20555 
                            September 13, 1979       IE Circular No. 79-19 


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

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 

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. 

Enclosure No. 2:    Excerpt from Combustion Engineering Inc. 
                    Letter to Nuclear Regulatory Commission, March 13, 1978 

         Enclosure No. 1 
                     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, 

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 

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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