ASME OM-2020 pdf download

ASME OM-2020 pdf download.Operation and Maintenance of Nuclear Power Plants.
ISTD-1000 INTRODUCTION ISTD-1100 Applicability The requirements of this Subsection apply to certain dynamic restraints (snubbers, pin to pin, inclusive). ISTD-1110 ð20Þ Exclusions. Examination of support struc- tures and attachments is outside the scope of this Code, except for examinations required for evaluation in accor- dance with ISTD-1800. 1 ISTD-1400 ð20Þ Owner’s Responsibility It is the Owner’s responsibility to meet all applicable requirements of Subsection ISTA and (a) make available design and operating information necessary for the performance of the examination and testing program. Nonmandatory Appendix C contains a list of typical information that may be useful. (b) identify and maintain a list of each snubber to be examined, tested, and included in service life monitoring in accordance with the rules of this Subsection. (c) specify acceptance criteria for examination and testing. (d) identify affected systems, structures, and compo- nents in accordance with ISTD-1800 and ISTD-4100 when the requirements of those paragraphs are applica- ble. ISTD-1500 Snubber Maintenance or Repair Snubber repair activities shall be performed in accor- dance with Section XI of the ASME Boiler and Pressure Vessel Code, as applicable. ISTD-1510 Maintenance or Repair Before Examina- tion or Testing. Snubbers shall not be adjusted, main- tained, or repaired before an examination or test specificallyto meetthe examination or testrequirements.
ISTD-1600 ð20Þ Snubber Modification and Replacement Snubber repair and replacement activities shall be performed in accordance with ASME BPVC, Section XI, as applicable. ISTD-1610 Suitability. Replacement or modified snubber(s) shall have a proven suitability for the applica- tion and environment. ISTD-1620 Examination and Testing. Replacement or modified snubbers shall be examined and tested in accor- dance with written procedures. The applicable require- ments of ISTD-4100, ISTD-4200, ISTD-5200, and ISTD-5500 shall be included in these procedures. The re- quirements selected shall ensure that the criteria of ISTD-4110, ISTD-4230, and ISTD-5210 can be satisfied. ISTD-1700 Deletions of Unacceptable Snubbers Snubbers may be deleted from the plant based on analysis ofthe affected piping system. When an unaccept- able snubber is deleted, the deleted snubber shall never- theless be considered in its respective examination population, examination category, or failure mode group (FMG) for determining the corrective action.
ISTD-1800 ð20Þ Evaluation of Affected Systems, Structures, and Components When a snubber is determined to be unacceptable, it is the owner’s responsibility to identify the extent to which any systems, structures, or components may be affected by the unacceptable condition. An evaluation shall be performedtodeterminepotentialeffectsandanyrequired corrective actions. ISTD-2000 ð20Þ DEFINITIONS The following list ofdefinitions is provided to ensure a uniform understanding of selected terms as used in this Subsection. activation: the change ofcondition from passive to active, in which the snubber resists rapid displacement of the attached pipe or component. application-induced failures: failures resulting from envi- ronmental conditions or application of the snubber for which it has not been designed or qualified. defined test plan group (DTPG): a population of snubbers from which samples are selected for testing. design or manufacturing failure: failures resulting from a potentialdefectinmanufacturingordesignthatgivecause to suspectothersimilarsnubbers. This includes failures of any snubber that fails to withstand the environment or application for which it was designed. diagnostic testing: testing to determine the cause or mechanism associated with failure, degradation, or performance anomaly of a snubber.
operating temperature: the temperature of the environ- mentsurrounding a snubber atits installed plantlocation duringthe phase ofplantoperation forwhich the snubber is required. operationalreadinesstesting: measurementofthe param- eters that verify snubber operational readiness. releaserate:the rateoftheaxialsnubbermovementunder aspecifiedloadafteractivationofthe snubbertakes place. replacementsnubber: anysnubber otherthan the snubber immediately previously installed at a given location. service life: the period of time a snubber is expected to meet the operational readiness requirements at its installed location without maintenance. service life monitoring: the ongoing actions necessary to provide reasonable assurance a snubber will continue to meet operational readiness requirements. These actions address the reevaluation of initial predicted service life values and typically include applicable items such as (a) use of test and visual examination results (b) failure or degradation cause analysis (c) manufacturer’s recommendations (d) maintenance practices (e) evaluation ofenvironmental factors corresponding to a snubber location service life population: those snubbers for which the same service life has been established. successful test campaign: campaign completed without having to test the entire defined test plan group (DTPG) population.