Browse wiki

Jump to navigation Jump to search
On January 4, 2008, Calvert Cliffs NuclearOn January 4, 2008, Calvert Cliffs Nuclear Power Plant received vendor confirmation that the temperature profile used to establish the As-Found Lift Setting for pressurizer safety valve 2RV200 (BV02950) in 2006 was not consistent with the temperature profile used to establish the valve's As-Left Lift Setting in 2003. As a result, the As-Found Lift Setting was outside the Technical Specification limits. Because 2RV200 had partially lifted during the November 16, 2006 Unit 2 reactor trip (Licensee Event Report 318/2006-001, Revision 1 dated February 23, 2007), the valve was removed and shipped to the vendor for As-Found testing and a complete refurbishment. Initially, the apparent cause evaluation determined that due to a loose compression screw/valve bonnet thread interface, thermal effects from the Unit 2 trip may have caused the lift setting to decrease during the event. However, a subsequent revision to the apparent cause evaluation determined that the low lift setting was caused by a difference in the temperature profiles. BV02950 was replaced with a valve set at the correct temperature profile.</br></br>All valves currently installed in Units 1 and 2 were verified to be set at the correct temperature profile. Procedures will be changed to reflect the effect of temperature changes on the setpoint and a checklist will be developed to track relief valve testing prior to installation.elief valve testing prior to installation.  +
On January 4, 2008, Calvert Cliffs NuclearOn January 4, 2008, Calvert Cliffs Nuclear Power Plant received vendor confirmation that the temperature profile used to establish the As-Found Lift Setting for pressurizer safety valve 2RV200 (BV02950) in 2006 was not consistent with the temperature profile used to establish the valve's As-Left Lift Setting in 2003. As a result, the As-Found Lift Setting was outside the Technical Specification limits. Because 2RV200 had partially lifted during the November 16, 2006 Unit 2 reactor trip (Licensee Event Report 318/2006-001, Revision 1 dated February 23, 2007), the valve was removed and shipped to the vendor for As-Found testing and a complete refurbishment. Initially, the apparent cause evaluation determined that due to a loose compression screw/valve bonnet thread interface, thermal effects from the Unit 2 trip may have caused the lift setting to decrease during the event. However, a subsequent revision to the apparent cause evaluation determined that the low lift setting was caused by a difference in the temperature profiles. BV02950 was replaced with a valve set at the correct temperature profile.</br></br>All valves currently installed in Units 1 and 2 were verified to be set at the correct temperature profile. Procedures will be changed to reflect the effect of temperature changes on the setpoint and a checklist will be developed to track relief valve testing prior to installation.elief valve testing prior to installation.  +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
6.944444e-5 d (0.00167 hours, 9.920635e-6 weeks, 2.283e-6 months)  +  and 1.388889e-4 d (0.00333 hours, 1.984127e-5 weeks, 4.566e-6 months)  +
1  +
2,008  +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
05:23:47, 1 December 2017  +
Processing error"Processing error" is a predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> and represents errors that appeared in connection with improper value annotations or input processing.
5E-07 +  and 5E-09 +
Pressurizer Safety Valve Setnoint Low Due to Different Temperature Profiles  +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.