ENS 45875
ENS Event | |
|---|---|
04:00 Mar 23, 2010 | |
| Title | Emd Jacket Water Pump with Incorrect Impeller Orientation |
| Event Description | The following is a summary of a report received from Engine Systems, Inc. via facsimile:
Engine Systems Inc. (ESI) began a 10CFR21 evaluation on 03/23/10 following a corrective action request from Entergy - Grand Gulf. The request was written as the result of Grand Gulf having an EMD jacket water pump with an incorrect impeller. Specifically, the impeller installed in the pump was for rotation opposite of the pump housing. The evaluation was concluded on 04/26/10 and was determined to be a reportable defect as defined by 10CFR21. EMD diesel engines utilized for emergency diesel generator sets use two engine jacket water centrifugal pumps (one for each bank) to circulate fluid throughout the engine for cooling. Each pump is mounted on the front of the engine and rotates in the opposite direction of the engine crankshaft. For single engine generator set applications (i.e. left hand rotation engine, viewed from the rear of the engine), the pumps used on each bank contain identical components; the only difference is the position of the impeller housing in relation to the pump shaft housing. When viewed from the front of the engine, these water pumps rotate counterclockwise (see Figure 1 below). For tandem generator set applications, one engine is left hand rotation and the other is right hand rotation. For each engine, the pumps used on each bank contain identical components and the only difference is the position of the impeller housing in relation to the pump shaft housing. However, for a right hand rotation engine the water pumps rotate clockwise when viewed from the front of the engine In summary, because these pumps use impellers that rotate in both clockwise and counter-clockwise directions, it is possible that an impeller could be installed with a design rotation opposite that required for the associated pump housing. A review has been performed to evaluate the impact on past supply of EMD water pumps. Historically, ESI has supplied a quantity of over 280 water pumps under 17 different EMD part numbers dating back to 1988. The pump returned by the customer [Grand Gulf] was supplied in January 1997. After reviewing the history of dedication activities performed on the water pumps it was found that dedication reports for EMD water pumps have always contained an inspection requirement to verify the correct operational rotation; however reports written prior to 2000 did not include a clear visual depiction of what the correct operational rotation is. It appears that this was an isolated incident where the inspector made an error when performing the inspection. Since April 2000, all EMD water pumps shipped were inspected to a dedication report that included a clear visual depiction of proper impeller geometry. This one incident is the only known instance of an EMD water pump with the incorrect impeller. ESI recommends that as a precaution, all customers with an EMD water pump in stock which was supplied by ESI prior to April 2000 should perform a visual inspection to ensure the correct impeller is installed. A pump which has been installed on the diesel engine is considered acceptable based on successful operation of the diesel engine. The impeller inspection is easily performed, without disassembly, by looking into the inlet port of the pump to confirm the orientation of the impeller matches the pump housing. A listing of the various part numbers supplied prior to April 2000 is included in Table [below]. Listing of Water Pump P/Ns Supplied Prior to April 2000 Part Number Rotation Bank Type of Engine 40004235 LH RIGHT 16 & 20-645E4 & E4B 40004234 LH LEFT 16 & 20-645E4 & E4B 8347607 LH LEFT 16 & 20-645E4 & E4B 8364236 RH RIGHT 16 & 20-645E4 & E4B 8364237 RH LEFT 16 & 20-645E4 & E4B 8269664 LH RIGHT 12-645E4 & E4B 9336390 LH LEFT 12-645E4 & E4B 8269638 LH LEFT 12-645E4 & E4B 8324588 RH RIGHT 12-645E4 & E4B 8324589 RH LEFT 12-645E4 & E4B NOTE: The ESI report did not provide an information on specific nuclear power plant licensees that may possess these components.
Two sentences were added to address the safety hazard which is created or could be created by this defect. Installation of the incorrect impeller would result in considerable loss of engine cooling water flow. This would cause elevated engine cooling water temperature that could impact engine performance and/or load carrying capability with the possibility of eventual engine failure, thereby preventing the emergency diesel generator from performing its safety related function. Notified R1DO (Powell), R2DO (Sykes), R3DO (Peterson), R4DO (Lantz), PART 21 GROUP via e-mail. |
| Where | |
|---|---|
| Engine Systems, Inc. Rocky Mount, North Carolina (NRC Region 1) | |
| Organization: | Engine Systems, Inc. |
| Reporting | |
| 10 CFR 21.21 | |
| Time - Person (Reporting Time:+829.25 h34.552 days <br />4.936 weeks <br />1.136 months <br />) | |
| Opened: | Paul Stepantschenko 17:15 Apr 26, 2010 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Apr 1, 2011 |
| 45875 - NRC Website | |
Engine Systems, Inc. with 10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation | |
WEEKMONTHYEARENS 458752010-03-23T04:00:00023 March 2010 04:00:00
[Table view]10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation Emd Jacket Water Pump with Incorrect Impeller Orientation 2010-03-23T04:00:00 | |