Information Notice No. 84-01: Excess Lubricant in Electric Cable Sheaths

                                                           SSINS No.: 6835 
                                                           IN 84-01        

                               UNITED STATES 
                           WASHINGTON, D.C. 20555 
                              January 10, 1984 

Information Notice No. 84-01:   EXCESS LUBRICANT IN ELECTRIC CABLE 


All nuclear power reactor facilities holding an operating license (OL) or 
construction permit (CP). 


This information notice is being issued to advise all addressees that under 
certain circumstances, excess lubricant may have become trapped inside cable
sheaths during manufacture, and may drip out where cable sheaths have been 
cut for terminations. 


By letter dated November 1, 1983, Illinois Power Company (IPC) notified the 
Administrator of NRC Region III of a situation where an oily fluid was 
observed seeping from cut ends of some power and control cables supplied by 
the Okonite Company for use at the Clinton Power Station. 

Investigation disclosed that it is the practice of the Okonite Company to 
apply an extruded filler material over the conductors of multiconductor 
cable, to provide a uniform cylindrical surface on which to apply the outer 
cable jacket. Before the jacket is applied, the exterior surface of the 
filler material is treated with an oily lubricant to facilitate the jacket 

Prior to early 1979, the filler material layer was so thin that sometimes 
the material tore in handling operations before the lubrication step. When 
this occurred, excess lubricant entered the cable bundle and remained there.
In early 1979, Okonite reports, the situation was identified and corrected 
by slightly increasing the thickness of the filler layer, and changing the 
formulation of the filler material. 

The Okonite Company states that presence of excess lubricant in cable in no 
way degrades the electrical characteristics or performance of the cable. 
IPC, while not disputing this position, is concerned that leakage of oil 
from the cable at terminations may create a fire hazard, and degrade other 
electrical equipment. 


                                                         IN 84-01          
                                                         January 10, 1984  
                                                         Page 2 of 2       

IPC has not used in Class IE service any cable exhibiting oil seepage 
characteristics. IPC further reports that Okonite has demonstrated to the 
satisfaction of IPC and its architect-engineer, Sargent and Lundy, that a 
Raychem heat-shrinkable "breakout" provides an acceptable seal to preclude 
oil seepage. 

The situation described above, while apparently unique to one manufacturer, 
is of a type which could develop in any multiconductor cable manufacturing 
operation. Several years ago large single conductor power cables were 
identified where water ran out between the strands of the conductor. The 
water was determined to be condensate from steam used in the insulation 
vulcanizing process. This notice recognizes the value of licensees and 
vendors being alert to identify and evaluate anomalous behavior of 
components used in their plants. Although no specific action or written 
response is required it is suggested that addressees review the information 
for applicability to their facilities. 

If you have any questions regarding this matter, please contact the Regional
Administrator of the appropriate NRC Regional Office, or this office. 

                                   Edward L. Jordan, Director 
                                   Division of Emergency Preparedness 
                                     and Engineering Response 
                                   Office of Inspection and Enforcement 

Technical Contact:  J. B. Henderson, IE 

Attachment:    List of Recently Issued IE Information Notices 

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