4.1 When more than one elastomer seal material is tested, the test methods yield comparative data on which to base judgements as to expected service quality. Suggested in-service property change limits are provided. Property changes beyond these limits will indicate limited service life of the elastomer seal.4.2 These test methods attempt to simulate service conditions through controlled aging and evaluation of property changes but may not give any direct correlations with actual part performance since actual service conditions vary widely. These test methods yield comparative data and indications of property changes of the elastomeric seal material under ideal service conditions. These test methods can be used for quality control purposes, for engineering assessments, for service evaluation, and for manufacturing control. The information from these test methods can be used to anticipate expected service quality.1.1 These test methods cover the procedure for measuring physical properties of elastomer seals in the form of O-rings after exposure to industrial hydraulic fluids and thermal aging. The measured properties are then compared to the physical properties of elastomer seals that have not been exposed to the industrial hydraulic fluids and thermal aging. The changes in these properties form a basis for assessing compatibility when these changes are compared against the suggested limits in Table 1.1.2 While these test methods involve the use of O-rings, they can also be used to evaluate the compatibility of the elastomeric compounds of specialty seals with industrial hydraulic fluids and their resistance to thermal aging. The compounds can be molded into O-rings for evaluation purposes.1.3 These test methods provide procedures for exposing O-ring test specimens to industrial hydraulic fluids under definite conditions of temperature and time. The resulting deterioration of the O-ring material is determined by comparing the changes in work function, hardness, physical properties, compression set, and seal volume after immersion in the test fluid to the pre-immersion values.1.4 The values stated in SI units are to be regarded as the standard.1.4.1 Exception—The values given in parentheses are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Precision statements for calculated values can be developed using this approach. Users can also evaluate how an individual test method’s precision influences the variability of calculated values.4.2 The standard deviation of a calculated value that is the sum, difference, product, or quotient of two or more test method results, each with their own precision statement, can be calculated so long as the individual variables (that is, test results) are independent and the standard deviations are small relative to their mean values. These restrictions are usually met in ASTM methods. In those cases where these restrictions are not met, other methods can be used. Only cases complying with the restrictions are covered in this standard.1.1 Material and mixture properties such as air voids and voids in mineral aggregates (VMA) are calculated from two or three test results, combined in simple mathematical relationships. The standard deviation equations for these calculated values can be developed using a mathematical process called “propagation of errors” (also called “propagation of uncertainty”). This practice includes uncertainty equations for four forms or material and mixture equations: when two test results are (1) added or subtracted, (2) multiplied together, (3) one divided by the other, and (4) two test results divided by a third.1.2 This approach to calculating standard deviation equations is only valid when the distributions of the test results from the two standards are independent (that is, not correlated).1.3 The accuracy of a calculated standard deviation is dependent on the accuracy of the standard deviations used for the individual test result methods.1.4 Values for the mean and standard deviation for each test method are needed to determine the standard deviation for a calculated value.1.5 Examples of how to use these equations are shown in Appendix X1.1.6 A brief explanation of how standard deviation equations are derived for more complicated material and mixture equations is also included.1.7 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method provides for measuring of the minimum conditions of a range of parameters (concentration of oxidant in a flowing mixture of oxidant and diluent, pressure, temperature) that will just support sustained propagation of combustion. For materials that exhibit flaming combustion, this is a flammability limit similar to the lower flammability limit, upper flammability limit, and minimum oxidant for combustion of gases (1).4 However, unlike flammability limits for gases, in two-phase systems, the concept of upper and lower flame limits is not meaningful. However, limits can typically be determined for variations in other parameters such as the minimum oxidant for combustion (the oxidant index), the pressure limit, the temperature limit, and others. Measurement and use of these data are analogous to the measurement and use of the corresponding data for gaseous systems. That is, the limits apply to systems likely to experience complete propagations (equilibrium combustion). Successful ignition and combustion below the measured limits at other conditions or of a transient nature are not precluded below the threshold. Flammability limits measured at one set of conditions are not necessarily the lowest thresholds at which combustion can occur. Therefore direct correlation of these data with the burning characteristics under actual use conditions is not implied.1.1 This test method covers a procedure for measuring the threshold-limit conditions to allow equilibrium of combustion of materials in various oxidant gases under specific test conditions of pressure, temperature, flow condition, fire-propagation directions, and various other geometrical features of common systems.1.2 This test method is patterned after Test Method D2863-95 and incorporates its procedure for measuring the limit as a function of oxidant concentration for the most commonly used test conditions. Sections 8, 9, 10, 11, 13, and for the basic oxidant limit (oxygen index) procedure are quoted directly from Test Method D2863-95. Oxygen index data reported in accordance with Test Method D2863-95 are acceptable substitutes for data collected with this standard under similar conditions.1.3 This test method has been found applicable to testing and ranking various forms of materials. It has also found limited usefulness for surmising the prospect that materials will prove “oxygen compatible” in actual systems. However, its results do not necessarily apply to any condition that does not faithfully reproduce the conditions during test. The fire limit is a measurement of a behavioral property and not a physical property. Uses of these data are addressed in Guides G63 and G94.NOTE 1: Although this test method has been found applicable for testing a range of materials in a range of oxidants with a range of diluents, the accuracy has not been determined for many of these combinations and conditions of specimen geometry, outside those of the basic procedure as applied to plastics.NOTE 2: Test Method D2863-95 has been revised and the revised Test Method has been issued as D2863-97. The major changes involve sample dimensions, burning criteria and the method for determining the oxygen index. The aim of the revisions was to align Test Method D2863 with ISO 4589-2. Six laboratories conducted comparison round robin testing on self-supporting plastics and cellular materials using D2863-95 and D2863-97. The results indicate that there is no difference between the means provided y the two methods at the 95 % confidence level. No comparison tests were conducted on thin films. The majority of ASTM Committee G4 favors maintaining the D2863-95 as the backbone of G125 until comprehensive comparison data become available.1.4 One very specific set of test conditions for measuring the fire limits of metals in oxygen has been codified in Test Method G124. Test Method G124 measures the minimum pressure limit in oxygen for its own set of test conditions. Its details are not reproduced in this standard. A substantial database is available for this procedure, although it is much smaller than the database for Test Method D2863-95. (Warning—During the course of combustion, gases, vapors, aerosols, fumes or any combination of these are evolved which may be hazardous.) (Warning—Adequate precautions should be taken to protect the operator.)1.5 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.6 This basic standard should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to directly describe or appraise the fire hazard or fire risk of materials, products or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use. The standard has more applicability in this regard at predicting the fire behavior of materials and components that are close in size to the test condition, than for systems that are much different (for example: comparing a test rod to a valve seat rather than comparing a test rod to a house or a particle).1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This standard provides a specification for elemental impurity limits in erosion control products used for land application. Erosion control products may include but are not limited to: hydraulically-applied erosion control products, rolled erosion control products, sediment retention devices, gabions and mattresses, and articulated concrete block revetments.1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this specification.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Sensory thresholds are used to determine the potential of substances at low concentrations to impart odor, taste, skinfeel, etc. to some form of matter. 5.2 Thresholds are used, for example, in setting limits for air pollution, in noise abatement, in water treatment, and in food systems. 5.3 Thresholds are used to characterize and compare the sensitivity of individual or groups to given stimuli, for example, in medicine, in ethnic studies, and in the study of animal species. 1.1 This practice describes a rapid test for determining sensory thresholds of any substance in any medium. 1.2 It prescribes an overall design of sample preparation and a procedure for calculating the results. 1.3 The threshold may be characterized as being either (a) only detection (awareness) that a very small amount of added substance is present but not necessarily recognizable, or (b) recognition of the nature of the added substance. 1.4 The medium may be a gas, such as air, a liquid, such as water or some beverage, or a solid form of matter. The medium may be odorless or tasteless, or may exhibit a characteristic odor or taste per se. 1.5 This practice describes the use of a multiple forced-choice sample presentation method in an ascending concentration series, similar to the method of limits. 1.6 Physical methods of sample presentation for threshold determination are not a part of this practice, and will depend on the physical state, size, shape, availability, and other properties of the samples. 1.7 It is recognized that the degree of training received by a panel of assessors with a particular substance may have a profound influence on the threshold obtained with that substance (1).2 1.8 Thresholds determined by using one physical method of presentation are not necessarily equivalent to values obtained by another method. 1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The LFL and UFL of gases and vapors define the range of flammable concentrations in air.5.2 This method measures the LFL and UFL for upward (and partially outward) flame propagation. The limits for downward flame propagation are narrower.5.3 Limits of flammability may be used to determine guidelines for the safe handling of volatile chemicals. They are used particularly in assessing ventilation requirements for the handling of gases and vapors. NFPA 69 provides guidance for the practical use of flammability limit data, including the appropriate safety margins to use.5.4 As discussed in Brandes and Ural,4 there is a fundamental difference between the ASTM and European methods for flammability determination. The ASTM methods aim to produce the best representation of flammability parameters, and rely upon the safety margins imposed by the application standards, such as NFPA 69. On the other hand, European test methods aim to result in a conservative representation of flammability parameters. For example, in this standard, LFL is the calculated average of the lowest go and highest no-go concentrations while the European test methods report the LFL as the minimum of the five highest no-go concentrations.NOTE 2: For hydrocarbons, the break point between nonflammability and flammability occurs over a narrow concentration range at the lower flammability limit, but the break point is less distinct at the upper limit. For materials found to be non-reproducible per 13.1.1 that are likely to have large quenching distances and may be difficult to ignite, such as ammonia and certain halogenated hydrocarbon, the lower and upper limits of these materials may both be less distinct. That is, a wider range exists between flammable and nonflammable concentrations (see Annex A1).1.1 This test method covers the determination of the lower and upper concentration limits of flammability of chemicals having sufficient vapor pressure to form flammable mixtures in air at atmospheric pressure at the test temperature. This test method may be used to determine these limits in the presence of inert dilution gases. No oxidant stronger than air should be used.NOTE 1: The lower flammability limit (LFL) and upper flammability limit (UFL) are sometimes referred to as the lower explosive limit (LEL) and the upper explosive limit (UEL), respectively. However, since the terms LEL and UEL are also used to denote concentrations other than the limits defined in this test method, one must examine the definitions closely when LEL and UEL values are reported or used.1.2 This test method is based on electrical ignition and visual observations of flame propagation. Users may experience problems if the flames are difficult to observe (for example, irregular propagation or insufficient luminescence in the visible spectrum), if the test material requires large ignition energy, or if the material has large quenching distances.1.3 Annex A1 provides a modified test method for materials (such as certain amines, halogenated materials, and the like) with large quenching distances which may be difficult to ignite.1.4 In other situations where strong ignition sources (such as direct flame ignition) is considered credible, the use of a test method employing higher energy ignition source in a sufficiently large pressure chamber (analogous, for example, to the methods in Test Method E2079 for measuring limiting oxygen concentration) may be more appropriate. In this case, expert advice may be necessary.1.5 The flammability limits depend on the test temperature and pressure. This test method is limited to an initial pressure of the local ambient or less, with a practical lower pressure limit of approximately 13 kPa (100 mm Hg). The maximum practical operating temperature of this equipment is approximately 150 °C.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This test method should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment that takes into account all of the factors pertinent to an assessment of the fire hazard of a particular end use.1.8 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification details the limits of variation for determining the chemical check analysis limits of cast or wrought nickel, nickel alloy and cobalt alloy parts and/or supplied material.1.1 This specification covers limits of variation for determining acceptability of the chemical composition of cast or wrought nickel, nickel alloy, and cobalt alloy parts and/or material supplied by a producer. Check analysis limits for elements or for ranges of elements not currently listed herein shall be as specified in the applicable material specification or as agreed upon by purchaser and supplier.1.2 In case of any conflicting requirements, the requirements of the purchase order, the individual material specification, and this general specification shall prevail in the sequence named.1.3 When specifically referenced in the material specification, the buyer may elect to apply check analysis limits to determine acceptability at his final acceptance or verification procedures. Check analysis limits are not permitted or are to be used by the producer for their own ladle or ingot analysis acceptance testing.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Commercial trace detectors are used by first responders, security screeners, the military, and law enforcement to detect and identify explosive threats and drugs of interest quickly. These trace detectors typically operate by detecting chemical agents in residues and particles sampled from surfaces and can have detection limits for some compounds extending below 1 ng. A trace detector is set to alarm when its response to any target analyte exceeds a programmed threshold level for that analyte. Factory settings of such levels typically balance sensitivity and selectivity assuming standard operating and deployment conditions.5.2 The LOD for a substance is commonly accepted as the smallest amount of that substance that can be reliably detected in a given type of medium by a specific measurement process (2). The analytical signal from this amount shall be high enough above ambient background variation to give statistical confidence that the signal is real. Methods for determining nominal LOD values are well known but pitfalls exist in specific applications. Vendors of trace detectors often report detection limits for only a single compound without defining the meaning of terms or reference to the method of determination.NOTE 2: There are several different “detection limits” that can be determined for analytical procedures. These include the minimum detectable value, the instrument detection limit, the method detection limit, the limit of recognition, the limit of quantitation, and the minimum consistently detectable amount. Even when the same terminology is used, there can be differences in the LOD according to nuances in the definition used, the assumed response model, and the type of noise contributing to the measurement.5.3 When deployed, the individual performance of a trace detector (for example, realistic LODs) is influenced by: (1) manufacturing differences, history, and maintenance; (2) operating configurations (for example, thermal desorption temperature, analyzer temperature, and type of swab); and (3) environmental conditions (for example, ambient humidity and temperature and chemical background). As a result, realistic LOD values for a trace detector may be poorly estimated by the factory specifications. These fundamental measures of performance are critically important for assessing the ability of an instrument to detect trace levels of particular compounds in a particular setting, so a reliable and accessible method is needed to estimate realistic LOD values, especially in the field.5.4 Technical Challenges and Pitfalls to the Estimation of LOD Values in Trace Detectors and the Setting of Optimal Alarm Thresholds: 5.4.1 —The U.S. Department of Justice lists over 230 explosive materials and over 270 controlled drugs having a high potential for abuse.4 There are many technologies used for trace detection, and instrument manufacturers design their systems and balance operating conditions to provide detection capabilities across as many analytes as possible. However, a very limited subset of analytes is normally used to test and verify detector performance. Therefore, default operating conditions and alarm thresholds may not be optimally set to detect reliably certain compounds deemed important in particular scenarios.5.4.2 Environment—Ambient conditions and chemical background vary with the deployment location, which would influence response sensitivities and LOD values.5.4.3 Risk Tolerance and Balance—Values of alpha risk (false positive probability of process blanks) and beta risk (false nondetection probability of analytes at the detection limit) should be balanced and set according to security priorities (for example, alert level, probable threat compounds, throughput requirements, human factors, and risk tolerance). The default risk balance in a trace detector may not be adequate for the deployment situation.5.4.4 Signal Variability (Heteroskedasticity)—The variance in instrument response may not be consistent across analyte mass levels introduced into the trace detector. In ion mobility spectrometry (IMS)-based technologies, the physicochemical mechanisms underlying atmospheric pressure ionization (with a finite number of available reactant ions) and ion mobility separation may be non-uniform across the response regions. Typical methods of LOD estimation usually assume constant variance.5.4.5 Proprietary Signal Processing—Typical LOD determinations assume Gaussian distributions and use background variation as an important parameter. Unfortunately, alarm decisions in trace detectors are rarely based on raw measurement signals; rather, proprietary algorithms are used to process the raw measurements. This processing may attempt to minimize alpha risk by truncating or dampening background signals, so background signals may be absent or the true distribution in these processed signals may be non-Gaussian, confounding the calculation of an accurate LOD.5.4.6 Multivariate Considerations—To improve selectivity and decrease alpha risk, alarm decisions in trace detectors may be based on multiple-peak responses rather than a single-peak amplitude measurement. Efforts to recognize and quantify unique ion fragmentation patterns across both the thermal desorption and drift-time domains are being developed for next-generation detectors.5.4.7 Diversity of Technologies—The wide variety of trace detectors and technologies on the market and those under development challenge general response models for accurate estimation of LOD.5.4.8 Security—LOD values for explosives in trace detectors may not be openly published because of security and classification issues.1.1 In harmony with the Joint Committee for Guides in Metrology (JCGM) and detection concepts of the International Union of Pure and Applied Chemistry (IUPAC) (1, 2)2, this test method uses a series of replicated measurements of an analyte at dosage levels giving instrumental responses that bracket the critical value, a truncated normal distribution model, and confidence bounds to establish a standard for estimating practical and statistically robust limits of detection.NOTE 1: Other standards are available that evaluate the general performance of detection technologies for various analytes in complex matrices (for example, Practice E2520).1.2 Here, the limit of detection (LOD90) for a compound is defined to be the lowest mass of that compound deposited on a sampling swab for which there is 90 % confidence that a single measurement in a particular trace detector will have a true detection probability of at least 90 % and a true nondetection probability of at least 90 % when measuring a process blank sample.1.3 This particular test method was chosen on the basis of reliability, practicability, and comprehensiveness across tested trace detectors, analytes, and deployment conditions. The calculations involved in this test method are published elsewhere (3), and are performed through an interactive web-based calculator available on the National Institute of Standards and Technology (NIST) site: https://www-s.nist.gov/loda.1.4 Intended Users—Trace detector developers and manufacturers, vendors, testing laboratories, and agencies responsible for public safety and enabling effective deterrents to terrorism.1.5 While this test method may be applied to any detection technology that produces numerical output, the method is especially applicable to measurement systems influenced by heterogeneous error sources that lead to non-linear and heteroskedastic dose/response relationships and truncated or censored response distributions at low analyte levels. The procedures have been tested using explosive and drug compounds in trace detectors based on ion mobility spectrometry, gas chromatography, and mass spectrometry (4). Compounds are deposited as liquid solutions on swabs and dried before use. Background interferences introduced to the test samples were representative of a variety of conditions expected during deployment, but these conditions were not intended as comprehensive in representing all possible scenarios. The user should be aware of the possibility that untested scenarios may lead to failure in the estimation of a reliable LOD90 value.1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Some specific hazards statements are given in Section 8 on Hazards.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Each test method has a limited precision. Even if a test is performed as carefully and as correctly as possible on a material which is as homogeneous as can be obtained, the test will still vary from one to another. A widely used measure of the variation of the test results from a test method is the standard deviation (σ). In an ASTM standard test method, the standard deviation of the test method can be found in the Precision and Bias statement for the test. The “Blue Book,” Form and Style for ASTM Standards, requires that all test methods include Precision and Bias statements. Practices C670 and C802 provide guidance for determination of these values.4.2 If the precision of a test method is low and the precision of the test has not been properly considered in a material specification, a uniform material with the right quality may still be rejected most of the time because of the wide variation of the test results. In order to have rational specification limits, the precision of the test used should be properly included in a specification.4.3 This practice provides a guideline for proper inclusion of precision of the test method in a rational specification.1.1 This practice covers a method of determining rational specification limits by inclusion of the precision of the test method used in the specification.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Alarm limits are used extensively for condition monitoring using data from in-service lubricant sample test results. There are many bases for initially choosing values for these alarm limits. There are many questions that should be addressed. These include:Are those limits right or wrong?Are there too many false positive or false negative results?Are they practical?5.2 This guide teaches statistical techniques for evaluating whether alarm limits are meaningful and if they are reasonable for flagging problems requiring immediate or future action.5.3 This guide is intended to increase the consistency, usefulness, and dependability of condition based action recommendations by providing machinery maintenance and monitoring personnel with a meaningful and practical way to evaluate alarm limits to aid the interpretation of monitoring machinery and oil condition as well as lubricant system contamination data.1.1 This guide provides specific requirements to statistically evaluate measurand alarm thresholds, which are called alarm limits, as they are applied to data collected from in-service oil analysis. These alarm limits are typically used for condition monitoring to produce severity indications relating to states of machinery wear, oil quality, and system contamination. Alarm limits distinguish or separate various levels of alarm. Four levels are common and will be used in this guide, though three levels or five levels can also be used.1.2 A basic statistical process control technique described herein is recommended to evaluate alarm limits when measurand data sets may be characterized as both parametric and in control. A frequency distribution for this kind of parametric data set fits a well-behaved two-tail normal distribution having a “bell” curve appearance. Statistical control limits are calculated using this technique. These control limits distinguish, at a chosen level of confidence, signal-to-noise ratio for an in-control data set from variation that has significant, assignable causes. The operator can use them to objectively create, evaluate, and adjust alarm limits.1.3 A statistical cumulative distribution technique described herein is also recommended to create, evaluate, and adjust alarm limits. This particular technique employs a percent cumulative distribution of sorted data set values. The technique is based on an actual data set distribution and therefore is not dependent on a presumed statistical profile. The technique may be used when the data set is either parametric or nonparametric, and it may be used if a frequency distribution appears skewed or has only a single tail. Also, this technique may be used when the data set includes special cause variation in addition to common cause variation, although the technique should be repeated when a special cause changes significantly or is eliminated. Outputs of this technique are specific measurand values corresponding to selected percentage levels in a cumulative distribution plot of the sorted data set. These percent-based measurand values are used to create, evaluate and adjust alarm limits.1.4 This guide may be applied to sample data from testing of in-service lubricating oil samples collected from machinery (for example, diesel, pumps, gas turbines, industrial turbines, hydraulics) whether from large fleets or individual industrial applications.1.5 This guide may also be applied to sample data from testing in-service oil samples collected from other equipment applications where monitoring for wear, oil condition, or system contamination are important. For example, it may be applied to data sets from oil filled transformer and circuit breaker applications.1.6 Alarm limit evaluating techniques, which are not statistically based are not covered by this guide. Also, the techniques of this standard may be inconsistent with the following alarm limit selection techniques: “rate-of-change,” absolute alarming, multi-parameter alarming, and empirically derived alarm limits.1.7 The techniques in this guide deliver outputs that may be compared with other alarm limit selection techniques. The techniques in this guide do not preclude or supersede limits that have been established and validated by an Original Equipment Manufacturer (OEM) or another responsible party.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Knowledge of flammable limits at elevated temperatures and pressures is needed for safe and economical operation of some chemical processes. This information may be needed in order to start up a reactor without passing through a flammable range, to operate the reactor safely and economically, or to store or ship the product safely.5.2 Limits of flammability data obtained in relatively clean vessels must be carefully interpreted and may not always be applicable to industrial conditions. Surface effects due to carbon deposits and other materials can significantly affect limits of flammability, especially in the fuel-rich region. Refer to Bulletin 503 and Bulletin 627.1.1 This practice covers the determination of the lower and upper concentration limits of flammability of combustible vapor-oxidant mixtures at temperatures up to 200°C and initial pressures up to as much as 1.38 MPa (200 psia). This practice is limited to mixtures which would have explosion pressures less than 13.79 MPa (2000 psia).1.2 This practice should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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