Information Notice No. 84-01: Excess Lubricant in Electric Cable Sheaths
SSINS No.: 6835
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
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
January 10, 1984
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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
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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