Терминология и определения методов тестирования, которые основываются на наблюдении, регистрации и анализе результатов взаимодействия физических полей или веществ с объектом контроля.
| integrated leakage rate test | Leakage test performed on an entire system or component by pressurizing the system to the calculated peak containment internal pressure related to the design, and then determining the overall inte... |
| ion current | Current that flows at all times from the positive emitter (heater) to the negative cathode collector of the heated anode (alkali ion) halogen vapor detector. this current increases in the presence... |
| ionization gauge | High vacuum gauge that depends on the measuring of electrical ion current resulting from ionization of gas. examples include hot filament ionization (bayard-alpert gauges) gauges; cold cathode ion... |
| isobaric | Having constant pressure. k |
| knudsen number | Ratio of mean free path to characteristic dimension of the system from nondestructive testing handbook, fourth edition: volume 2, leak testing © 2017. (roep’hrinatendl wointh 1 p9er8m9i)ss.ion of ... |
| lack of penetration | See incomplete penetration. glossary l 503 lambert’s cosine law: in nondestructive testing, physical law stating that the illumination of a surface varies as the cosine of the incidence angle. max... |
| leak detector | Device for detecting, locating, or measuring leakage. leak testing (lt): nondestructive testing method for detecting, locating, or measuring leaks or leakage in pressurized or evacuated systems or... |
| leakage design basis accident | Calculated peak containment internal pressure related to the design basis accident. |
| leaker penetrant | - Penetrant especially designed for leak detection.
- Liquid penetrant designed for leak testing and providing a trace under ultraviolet or visible radiation. leak testing (lt): nondest...
|
| leech box | Double compartmented box in which the outer compartment is evacuated and then the inner compartment is pressurized to produce a pressure differential across the test boundary under the inner compa... |
| lid stiffness | In leak testing of hermetically sealed packages, the material characteristic that defines the amount of lid deflection from a specific pressure differential. lt: leak testing. m |
| light contamination | - In fluorescent nondestructive testing, unwanted visible light present in darkened test area. sources may include gaps in curtains, leaked visible light from the uv-a source, or fluorescence fr...
|
| liquid penetrant | Fluid used in liquid penetrant testing. see penetrant. liquid penetrant testing (pt): see penetrant testing. |
| luminous exitance | Luminous flux per area, emitted or reflected from a certain location on a surface. measured in lumens per square meter (lm/m2). compare radiant exitance. |
| lux meter | Device used to measure illuminance. see also photometer. m |
| manual zero | Control on a test instrument that allows the user to zero the instrument panel meter. |
| mass spectrometer leak detector | Mass spectrometer with design factors optimized to produce an instrument that has high sensitivity to a single tracer gas. mass-to-charge ratio: ratio of mass (kilogram) to electrical charge (coul... |
| molecular flow | Phenomenon occurring when the mean free path length of gas molecules is greater than the largest cross sectional dimension of a leak or the tube through which flow is occurring. see also knudsen n... |
| motion feedthrough | Function provided by rotary or linear drives that penetrates the vacuum boundary to operate valve or pump or perform another function inside the vacuum system. see also vacuum grease. n ndc: nonde... |
| near ultraviolet | Pertaining to electromagnetic radiation with wavelengths between 315 and 400 nm. fluorescent tracer liquids for leak testing use ultraviolet energy centered around 365 nm. |
| near ultraviolet filter | Device used to modify the emission spectrum from an ultraviolet radiation source by eliminating most visible light and high energy (far ultraviolet) radiation. nondestructive characterization (ndc... |
| oil and whiting | Method of locating cracks by applying penetrating liquid (oil) to an object and then removing excess from the surface. after the surface is coated with chalk (whiting), penetrating liquid seeps ou... |
| one or more of the following | Recognition of the presence of something (object, aperture, or medium); identifying it; locating it in space; noting its relation to other things; identifying its movement, color, brightness or fo... |
| optical leak testing | Leak testing method using optical means such as holographic laser interferometry. optical leak testing is used, for example, on microelectronic and pharmaceutical packaging. |
| overall integrated leakage rate | Total leakage through all paths including containment welds, valves, fittings, and components that penetrate a primary reactor containment system, expressed in weight percent of contained air mass... |
| overemulsification | Removal of penetrant from some discontinuities due to excessive contact time between the emulsifier and sample. |
| overwashing | Removal of penetrant from some discontinuities due to excessive rinsing time and/or rinsing action. p |
| penetrant leak testing | - Technique of penetrant testing in which the penetrant is applied to one surface of a test material while the opposite surface is tested for indications that would identify a leak or void passi...
|
| penetration time | See dwell time. |
| pirani gauge | Bridge circuit that measures the effect of gas conductivity changes corresponding to pressure variations. measures pressure from atmospheric down to 0.1 pa (1 mtorr). |
| polychromator spectrometer | Low cost measurement device that contains a linear charge coupled device array and stationary grating. |
| postcleaning | Removal of penetrant testing residues from the test piece at the end of a penetrant test. compare cleaning. |
| postemulsification | Penetrant removal step that uses a separate emulsifier applied over the surface penetrant to render it removable by water spray. see also emulsifier, hydrophilic; emulsifier lipophilic. |
| powder bulb | - Pneumatic device compressed by hand to deliver a cloud of dry powder developer to the surface of a test object.
- Container compressed by hand to deliver a cloud of dry magnetic parti...
|
| prerinse technique | Postemulsifiable penetrant removal step in which major portion of a nonwater washable penetrant is mechanically removed with a water spray before application of emulsifier. sometimes called prewas... |
| pressure proof test | Test of system at pressure considerably above the allowable working pressure to demonstrate structural capability. see also structural integrity test. |
| probe gas | Tracer gas that issues from a fine orifice in a tracer probe so as to impinge on a restricted (small) test area. |
| process testing | Initial product testing to establish correct manufacturing procedures, and then by periodic tests to ensure that the process continues to operate correctly. |
| proportioning probe | Probe that can vary the tracer gas concentration in the sample at the sensor, typically by mixing pure air with sample gas from the probe inlet port. ratios of mixture between 100 percent pure air... |
| pumping speed | Volumetric speed at which gas is transported, expressed in cubic meters per second. |
| pure air supply | In leak testing, air that has been cleaned of halogen contamination by means of an activated charcoal filter. this term is sometimes also used to describe any nonreactive gas, such as nitrogen, th... |
| quenching of fluorescence | Extinction of fluorescence by causes other than removal of the ultraviolet radiation (the exciting radiation). r |
| radiant exitance | Radiant power per area, emitted or reflected from a certain location on a surface. measured in watts per square meter (w/m2). compare luminous exitance. |
| radioactivity leak test | Leak test using radioactive tracer gas such as krypton-85, detected by its emission of radioactive decay products. |
| rankine | Disused scale for absolute temperature and related to the fahrenheit relative scale. the rankine unit (°r) is equal to 1 °f; 0 °r = –459.72 °f. rat’s tooth principle: (1) the tendency for hard mat... |
| rebleed technique | See bleed back technique. recommended practice no. snt-tc-1a, personnel qualification and certification in nondestructive testing: set of guidelines for employers to establish and conduct a nondes... |
| relative measurement | Evaluation of a property that is based upon some variable rather than a calibration standard. for example, relative irradiance would evaluate one radiation source based upon the emission of anothe... |
| relevant indication | - See indication, relevant.
- In nondestructive testing, an indication from a discontinuity or condition and requiring evaluation.5
- In nondestructive testing, an indication f...
|
| response factor | Experimentally determined correction of a detector’s measurement (that is, area under the curve) to account for its unique sensitivity to a given compound. in leak testing, it may be a halogen lea... |
| rockwell hardness testing | Evaluation method for determining the hardness of a material by forcing an indenter into it under specified conditions. conditions and indenter type and size vary with the rockwell hardness scale ... |
| roots blower | Blower that uses two lobed rotors mounted on parallel shafts in conjunction with mechanical pumps to obtain greater pumping speeds and lower pressures. see also pump, mechanical. |
| sampling probe | See detector probe. sampling, random partial: partial sampling that is fully random. sampling, specified partial: partial sampling in which a particular frequency or sequence of sample selection i... |
| scuff mark | Area covered by fine scratches, usually due to rubbing of one piece against another. |
| sniffer probe | See detector probe. snt-tc-1a: see asnt recommended practice no. snt-tc-1a. |
| solution film | Thin continuous film of bubble solution used in bubble testing (o’hanlon 1989). |
| solvent removal | Process of removing excess penetrant from the surface of a test object by hand wiping with a solvent dampened cloth. see also color contrast penetrant; fluorescent penetrant. |
| spectrofluorometer | Instrument capable of determining the fluorescent excitation and fluorescent emission spectra of a sample. |
| star burst panel | See penetrant system monitor. |
| static testing | See accumulation test technique. structural integrity test (sit): test that demonstrates the capability of a vessel to withstand specified internal pressure loads. see also pressure proof test. |
| temperature envelope | Temperature range over which a particular penetrant testing technique will operate. |
| tesla coil | High voltage spark coil (several thousand volts), which identifies leaks in nonconductive vessels through ionization and avalanche multiplication (the townsend discharge). |
| thermal conductivity vacuum gauge | Instrument that operates on principle that, as gas molecules are removed from a system, the amount of heat transfer by conduction is reduced. this relationship is used to indicate absolute pressur... |
| thermal disorption | Release of gases or vapors from the interior wall of a vacuum system by heat (o’hanlon 1989). |
| thermal equilibrium | Condition of an object wherein temperatures throughout the object remain constant. |
| tracer probe test | Localized leak test in which a tracer is introduced to portions of the external surface of an evacuated specimen by means of a probe, and simultaneously, a leak detector in line with the vacuum pu... |
| transfer standard | In penetrant testing and magnetic particle testing, precision radiometric measurement instrument with nist traceable calibration used to calibrate radiation reference sources. compare reference st... |
| transition flow | Phenomenon that occurs when the mean free path of gas is about equal to the cross sectional dimension of a leak or the tube through which flow is occurring. compare laminar flow; turbulent flow. |
| two categories | Flexible and rigid. borescope, blending: borescope comprised of a flexible shaft and a rotary tool to smooth out (blend) damage. there are generally custom designed kits for use with specific appl... |
| ultimate pressure | Lowest pressure that can be achieved in a vacuum chamber after cleaning and baking (o’hanlon 1989). |
| ultrasonic leak test | Leak test that detects acoustic vibration frequencies approximately in the 40 khz range, which are produced by gas flowing through the leak path. |
| units are basic | Meter, mole, kilogram, second, ampere, kelvin, and candela. |
| vacuum box | Device used to create a differential pressure over an isolated area of a weld or of a pressure boundary that cannot be directly pressurized. |
| vacuum box leak testing | Technique of bubble testing where a vacuum box is used to create a pressure differential across a boundary. a viewing window allows observation of bubble formation within the solution film. |
| vacuum grease | Substance commonly used to attain a seal and to lubricate devices such as stopcocks and motion feedthrough penetrations. |
| vacuum pressure testing | Leak testing procedure in which the test object containing a tracer is placed in an evacuated enclosure and the tracer gas is detected after entering the enclosure. also called bell jar testing. c... |
| verification test | Tests intended to confirm the capability of leak test technique and equipment to determine leakage rate. |
| virtual leak | Emission of gas in a vacuum system that results from condensable or trapped gases. they gradually evaporate from surfaces or escape from pockets, raising the absolute pressure in the same manner a... |
