ML16112A210

National Technical Systems - Potential Part 21 on Siemens 401-158 Safety Clip, Per Wolf Creek, Salem, and Arkansas Nuclear One

ML16112A210
Person / Time
Site:	Salem, Wolf Creek, Arkansas Nuclear
Issue date:	03/14/2016
From:	Toomey M National Technical Systems
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML16112A210 (1)

Text

s March 14, 2016 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Potential Part 21 on Siemens 401-158 Safety Clip Pursuant to the requirements of 10CFR Part 21, this letter notifies the NRC of a potential Part 21 condition. The subject Safety Clip is used in medium voltage circuit breakers. The subject circuit breakers are manufactured as a commercial grade item by Siemens Industry Inc. and dedicated for use as a basic component by National Technical Systems (NTS). Affected circuit breakers are 350 MVA Siemens Type 3AF. The Safety Clip in question is made of black finish steel and retains the Close Pawl Roller.

During an inspection at Wolf Creek Nuclear Operating Company, the subject Safety Clips, were found cracked, broken, missing, or degraded after 600 to 850 operations. If the Safety Clip breaks and falls off and the washers and roller pawl outside bearing and race fall off, then future circuit breaker close operations beyond the next close cycle may not be assured.

National Technical Systems has provided the 350 MVA Siemens Type 3AF circuit breakers to WCNOC Wolf Creek, PSEG Nuclear LLC Salem, and Entergy ANO. NTS will contact each utility and recommend that Safety Clip part number 401-158 be inspected and replaced with Safety Clip part number 40115.

This Safety Clip is a yellow zinc plated clip of different design, and no known problems exist with this Safety Clip on different type Siemens circuit breakers dedicated by NTS.

NTS will perform a failure analysis to determine the nature of the 401-158 clip failure. NTS plans to complete this analysis by April 29, 2016.

If you have any questions, please contact NTS' Senior Director of Nuclear Engineering and Test Services, Tom Brewington at (256) 716-4512 or email at tom.brewington@nts.com.

Sincerely,

.-*****~~

~2~;--- . - -- *- --- ----

Megan Toomey Sr. Contracts Manager NTS Huntsville NTS Huntsville

• 7800 Highway 20 West

• Huntsville, AL 35806 * (256) 837-4411

• Fax: (256) 830-2109

• www.nts.com

s March 14, 2016 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Potential Part 21 on Siemens 401-158 Safety Clip Pursuant to the requirements of 10CFR Part 21, this letter notifies the NRC of a potential Part 21 condition. The subject Safety Clip is used in medium voltage circuit breakers. The subject circuit breakers are manufactured as a commercial grade item by Siemens Industry Inc. and dedicated for use as a basic component by National Technical Systems (NTS). Affected circuit breakers are 350 MVA Siemens Type 3AF. The Safety Clip in question is made of black finish steel and retains the Close Pawl Roller.

During an inspection at Wolf Creek Nuclear Operating Company, the subject Safety Clips, were found cracked, broken, missing, or degraded after 600 to 850 operations. If the Safety Clip breaks and falls off and the washers and roller pawl outside bearing and race fall off, then future circuit breaker close operations beyond the next close cycle may not be assured.

National Technical Systems has provided the 350 MVA Siemens Type 3AF circuit breakers to WCNOC Wolf Creek, PSEG Nuclear LLC Salem, and Entergy ANO. NTS will contact each utility and recommend that Safety Clip part number 401-158 be inspected and replaced with Safety Clip part number 40115.

This Safety Clip is a yellow zinc plated clip of different design, and no known problems exist with this Safety Clip on different type Siemens circuit breakers dedicated by NTS.

NTS will perform a failure analysis to determine the nature of the 401-158 clip failure. NTS plans to complete this analysis by April 29, 2016.

If you have any questions, please contact NTS' Senior Director of Nuclear Engineering and Test Services, Tom Brewington at (256) 716-4512 or email at tom.brewington@nts.com.

Sincerely,

.-*****~~

~2~;--- . - -- *- --- ----

Megan Toomey Sr. Contracts Manager NTS Huntsville NTS Huntsville

• 7800 Highway 20 West

• Huntsville, AL 35806 * (256) 837-4411

• Fax: (256) 830-2109

• www.nts.com