Wednesday, January 08, 2020

Unforseen Cracks In PWR CRDMs

See, this could be like the Davis Besse leaking CRDM beginning at Oconee. They had these host of leaking CRDMs and cracks the industry where constantly downplaying. One day a employee working on top of the head stumble, he grabbed the CRDM housing where he found it lose as hell. It almost surely would have created a meltdown if the crack would have burst.    

Westinghouse Non-Proprietary Class 3
@Westinghouse
U.S. Nuclear Regulatory Commission Document Control Desk 11555 Rockville Pike Rockville, MD 20852
Westinghouse Electric Company 1000 Westinghouse Drive Cranberry Township, Pennsylvania 16066 USA
Direct tel: (412) 374-2577 Direct fax: (724) 940-8542 e-mail: zozulact@westinghouse.com
LTR-NRC-19-79
December 12, 2019
Subject: Notification of the Potential Existence of Defect Pursuant to 10 CFR Part 21
The following information is provided pursuant to the requirements of 10 CFR Part 21 to report a defect that could lead to a substantial safety hazard (SSH.)
During a 2019 planned outage at a Westinghouse plant, site personnel identified a fractured and dislocated control rod drive mechanism (CROM) thermal sleeve. The fracture occurred just beneath the worn area of the flange in the full cross-section of the thermal sleeve tube. A stress concentration exists at this transition. Previous operating experience (OE) with thermal sleeve failures did not include a crosssectional thermal sleeve fracture such as this.
Additional data supplied from the affected plant showed evidence of additional thermal sleeve locations with crack-like indications in the flange collar region (i.e., evidence of degradation but not failure). Although there was no evidence that control rod motion was hindered, Westinghouse is conservatively reporting this condition as having the potential to create a SSH, were it to remain uncorrected. 
They are not supposed to use these abbreviations. There are suppose to use plain language. This just goes to the extent they obscuring the true conditions of the industry.     

(i) Name and address of the individual or individuals informing the Commission.
Camille T. Zozula Westinghouse Electric Company 1000 Westinghouse Drive Cranberry Township, Pennsylvania 16066
(ii) Identification of the facility, the activity, or the basic component supplied for such facility or such activity within the United States which fails to comply or contains a defect.
Based on the recent OE where an additional means of mechanical failure has been identified (i.e., fracture, in addition to flange wear) and is not specifically being inspected for, there is a potential that one or more drive rods (basic components) could become jammed by a thermal sleeve flange remnant.
(iii) Identification of the firm constructing the facility or supplying the basic component which fails to comply or contains a defect.
Westinghouse Electric Company

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