真空试验程序

ShandongNuclearPowerEquipmentManufacturingCo.Ltd.PageShandongNuclearPowerEquipmentManufacturingCo.Ltd.Pageof7需要记录至少15Kpa的负压。Thevacuitycanbeformedbyanyofthepracticalandconvenientmethods(suchasairinjector,suctionpump),thevacuumgaugeneedtorecordatleastanegativepressureof15Kpa试验压力TestPressure依据API620标准，试验时应保持真空盒内压力为一21Kpa〜一35Kpa的压力。Thepressureinsidetheboxshallbekeptas-21Kpa〜-35KpaduringthetestaccordingtoAPI620requirements.压力保持PressureMaintenance在试验时，真空盒要保持真空状态(负压)至少10秒钟。Thevacuumcondition(negativepressure)shallbemaintainedatleast10sec.whilsttesting.真空盒重叠检查OverlapofVacuumBox对同一长度连续焊缝的真空试验，为保证100%试验范围及检测结果的准确，对真空盒的重叠长度应保持50mm。Theoverlaplengthshallbekept50mmtomakesureof100%testingscopeandtheaccuracyoftestresultwhendoingavacuumtesttothecontinuousweldofthesamelength.灯光和视觉观察LightingandVisualObservation(1)当观察者眼睛距离被测试表面在600mm内，视线与被测表面角度在30度以内的情况下，可直接进行视觉检测。可以使用镜子来改善视觉角度或者使用放大镜来辅助检查。其中对某些特殊部位、部件、容器等的检测，合适的照明(自然的或外加的白光)是必要的。被测表面的最低光照强度可以是100lux。光照强度、所用技术、光线等级证明等需要一次性记录在档案上。Directvisualinspectionisdoablewhenthetester’seyeiswithinadistanceof600mmfromthesurfacebeingtestedandthelookangleofeyeandthesurfaceiswithin30°.Mirrorcanbeusedtoimprovethesightangleoruseloupetoassisttheinspection.Suitablelighting(naturaloradscititiouswhitelight)isnecessaryforthetestingofspeciallocations,partsandcontainersthelowestlightingintensityonthesurfacemaybe100lux.Thelightingintensity,techniqueused,lightgradecertificateshallberecordedinthefileone-off.在某些情况下，远距离视觉观察要替代近距离视觉观察。远距离视觉检查要用到比如镜子、望远镜等辅助设备。Closevisualobservationshallbereplacedbydistancevisualobservationinsomecases.Supplementaryappliancesbeingusedtotheclosevisualobservationaremirror,telescopeandsoon.泄露指示LeakageIndication检测区域若是有连续气泡冒出，说明被检区域表面或焊缝有孔道缺陷。Therearedrill-waydefectsonthesurfacebeingtestedorattheweldseamifbubblesgeneratedcontinuouslyfromtheareabeingtested.清洁Cleaning检测完毕后要按要求将检测部位清洁使达到使用要求。Cleanthetestedareaaccordingtorelativerequirementsafterthetesting.■评价Evaluation泄露缺陷LeakageDefects如相关规范无专门说明，则检验部位若观察无连续气泡产生，就认为产品真空检验合格。Itwillbeconsideredqualifiedifthereisnocontinuousbubbleformingatthetestedlocationwhenthereisnospecificinstructioninrelativecodes.(2)返修/重新检测Repair/Re-test若焊缝观察到有泄露部位，则应在此部位做上记号，真空盒排空，缺陷部位按相关规范要求进行返修，返修后按要求进行重新真空检验。Markthoseleakagelocationsandevacuatethevacuumbox,repairthosedefectsaccordingtorelativecodesrequirements,andre-testingofvacuumisrequiredafterrepair.操作人员资质OperatorQualification真空试验操作人员的资质依照ASMEIIINE-5500的要求执行。Qualificationofvacuumtestoperatorshallbeconsistentwit