定价： 590元 / 折扣价： 502 元 加购物车

定价： 646元 / 折扣价： 550 元 加购物车

4.1 The analyzer site precision is an estimate of the variability that can be expected in a UAR or a PPTMR produced by an analyzer when applied to the analysis of the same material over an extended time period.4.2 For applications where the process analyzer system results are required to agree with results produced from an independent PTM, a mathematical function is derived that relates the UARs to the PPTMRs. The application of this mathematical function to an analyzer result produces a predicted PPTMR. For analyzers where the mathematical function, that is, a correlation, is developed by D7235, the analyzer site precision of the UARs is a required input to the computation.4.3 After the correlation relationship between the analyzer results and primary test method results has been established, a probationary validation (see D3764 and D6122) is performed using an independent but limited set of materials that were not part of the correlation activity. This probationary validation is intended to demonstrate that the PPTMRs agree with the PTMRs to within user-specified requirements for the analyzer system application. The analyzer site precision is a required input to the probationary validation procedures.4.3.1 If the process stream analyzer system and the primary test method are based on the same measurement principle(s), or, if the process stream analyzer system uses a direct and well-understood measurement principle that is similar to the measurement principle of the PTM then validation is done via D3764. Practice D3764 also applies if the process stream analyzer system uses a different measurement technology from the PTM, provided that the calibration protocol for the direct output of the analyzer does not require use of the PTM.4.3.2 If the process stream analyzer system utilizes an indirect or mathematically modeled measurement principle such as chemometric or multivariate analysis techniques where PTMRs are required for the development of the chemometric or multivariate model, then validation of the analyzer is done using Practice D6122.4.3.3 Both the D3764 and D6122 validation practices utilize the statistical methodology of Practice D6708 to conduct the probationary validation. This methodology requires that the site precision for the PTM and the analyzer site precision be available.4.4 The procedures described herein also serve as the basis for a process analyzer quality control system. A representative sample of the QC material is introduced into the analyzer system in a repeatable fashion. Such sample introduction permits capturing the effect of the analyzer system operating variables on the UAR and PPTMR output signal from the process analyzer. By comparing the observed analyzer responses to the expected response for the QC sample, the fitness for use of the analyzer system can be determined.1.1 This practice describes a procedure to quantify the site precision of a process analyzer via repetitive measurement of a single process sample over an extended time period. The procedure may be applied to multiple process samples to obtain site precision estimates at different property levels1.1.1 The site precision is required for use of the statistical methodology of D6708 in establishing the correlation between analyzer results and primary test method results using Practice D7235.1.1.2 The site precision is also required when employing the statistical methodology of D6708 to validate a process analyzer via Practices D3764 or D6122.1.2 This practice is not applicable to in-line analyzers where the same quality control sample cannot be repetitively introduced.1.3 This practice is meant to be applied to analyzers that measure physical properties or compositions.1.4 This practice can be applied to any process analyzer system where the feed stream can be captured and stored in sufficient quantity with no stratification or stability concerns.1.4.1 The captured stream sample introduction must be able to meet the process analyzer sample conditioning requirements, feed temperature and inlet pressure.1.4.2 This practice is designed for use with samples that are single liquid phase, petroleum products whose vapor pressure, at sampling and sample storage conditions, is less than or equal to 110 kPa (16.0 psi) absolute and whose D86 final boiling point is less than or equal to 400 °C (752 °F).NOTE 1: The general procedures described in this practice may be applicable to materials outside this range, including multiphase materials, but such application may involve special sampling and safety considerations which are outside the scope of this practice.1.5 The values for operating conditions are stated in SI units and are to be regarded as the standard. The values given in parentheses are the historical inch-pound units for information only.1.6 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.1.7 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 ASTM regulations require precision statements in all test methods in terms of repeatability and reproducibility. This practice may be used in obtaining the needed information as simply as possible. This information may then be used to prepare a precision statement in accordance with Practice E177. Knowledge of the test method precision is useful in commerce and in technical work when comparing test results against standard values (such as specification limits) or between data sources (different laboratories, instruments, etc.).4.1.1 When a test method is applied to a large number of portions of a material that are as nearly alike as possible, the test results obtained will not all have the same value. A measure of the degree of agreement among these test results describes the precision of the test method for that material. Numerical measures of the variability between such test results provide inverse measures of the precision of the test method. Greater variability implies smaller (that is, poorer) precision and larger imprecision.4.1.2 Precision is reported as a standard deviation, coefficient of variation (relative standard deviation), variance, or a precision limit (a data range indicating no statistically significant difference between test results).4.1.3 This practice is designed only to estimate the precision of a test method. However, when accepted reference values are available for the property levels, the test result data obtained according to this practice may be used in estimating the bias of the test method. For a discussion of bias estimation and the relationships between precision, bias, and accuracy, see Practice E177.4.2 The procedures presented in this practice consist of three basic steps: planning the interlaboratory study, guiding the testing phase of the study, and analyzing the test result data.4.2.1 The planning phase includes forming the ILS task group, the study design, selection, and number of participating laboratories, selection of test materials, material certifications if applicable, and writing the ILS protocol. A well-developed test method is essential, so including a ruggedness test to determine control of test method conditions is highly recommended.NOTE 1: In this practice, the term test method is used both for the actual measurement process and for the written description of the process, while the term protocol is used for the directions given to the laboratories for conducting the ILS.4.2.2 The testing phase includes material preparation and distribution, liaison with the participating laboratories, and handling of test result data received from the laboratories.4.2.3 The data analysis utilizes tabular, graphical, and statistical diagnostic tools for evaluating the consistency of the data so that unusual values may be detected and investigated, and also includes the calculation of the numerical measures of precision of the test method pertaining to repeatability and reproducibility.4.3 The information in this practice is arranged as follows:  Section 1Referenced Documents 2Terminology 3 4Concepts of Test Method Precision 5   Planning the Interlaboratory Study (ILS) Section ILS Membership 6 Basic Design 7 Test Method 8 Laboratories 9 Materials 10 Number of Test Results per Material 11 Protocol 12   Conducting the Testing Phase of the ILS Section Pilot Run 13 Full Scale Run 14   Calculation and Display of Statistics Section Calculation of the Statistics 15 Tabular and Graphical Display of Statistics 16   Data Consistency Section Flagging Inconsistent Results 17 Investigation 18 Task Group Actions 19 Glucose ILS Consistency 20   Precision Statement Information Section Repeatability and Reproducibility 21     SectionKeywords 22   Tables Table Glucose in Serum Example 1–4, 6–8 Critical Values of Consistency Statistics, h and k 5   Figures Figure Glucose in Serum Example 1–3   Annexes Annex Theoretical Considerations Annex A1 Calculation of the ILS Statistics for Unbalanced Data Sets Annex A2   Appendixes Appendix Spreadsheet for E691 Calculations Appendix X1AbstractThis practice describes the techniques for planning, conducting, analyzing, and treating the results of an interlaboratory study (ILS) of a test method. The statistical techniques described in this practice provide adequate information for formulating the precision statement of a test method. This practice is also concerned exclusively with test methods which yield a single numerical figure as the test result, although the single figure may be the outcome of a calculation from a set of measurements. ASTM regulations require precision statements in all test methods in terms of repeatability and reproducibility and knowledge of the test method precision is useful in commerce and in technical work when comparing test results against standard values or between data sources.1.1 This practice describes the techniques for planning, conducting, analyzing, and treating the results of an interlaboratory study (ILS) of a test method. The statistical techniques described in this practice provide adequate information for formulating the precision statement of a test method.1.2 This practice does not concern itself with the development of test methods but rather with gathering the information needed for a test method precision statement after the development stage has been successfully completed. The data obtained in the interlaboratory study may indicate, however, that further effort is needed to improve the test method.1.3 Since the primary purpose of this practice is the development of the information needed for a precision statement, the experimental design in this practice may not be optimum for evaluating materials, apparatus, or individual laboratories.1.4 Field of Application—This practice is concerned exclusively with test methods which yield a single numerical figure as the test result, although the single figure may be the outcome of a calculation from a set of measurements.1.4.1 This practice does not cover methods in which the measurement is a categorization; however, for many practical purposes categorical outcomes can be scored, such as zero-one scoring for binary measurements or as integers, ranks for example, for well-ordered categories and then the test result can be defined as an average, or other summary statistic, of several individual scores.1.5 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.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 The purpose of this guide is to report on the testing of, to discuss and compare the properties of, and to provide guidelines for the choice of lubricating greases for precision rolling element bearings (PREB). The PREB are, for the purposes of this guide, meant to include bearings of Annular Bearing Engineer's Committee (ABEC) 5 quality and above. This guide limits its scope to lubricating greases used in PREB.4.2 The number of lubricating greases used in PREB increased dramatically from the early 1940s to the mid 1990s. In the beginning of this period, petroleum products were the only widely available base stocks. Later, synthetic base oils became available. They included synthetic hydrocarbons, esters, silicones, multiply alkylated cyclopentanes (MAC) and fluorinated materials, including perfluorinated ethers and the fluorosilicones. This broad spectrum of lubricant choices has led to the use of a large number of different lubricants in PREB applications. The U.S. Department of Defense, as a user of many PREB, has seen a significant increase in the logistics effort required to support the procurement and distribution of these items. In addition, as time has passed, some of the greases used in certain PREB are no longer available or require improved performances due to advanced bearing technology/requirements. This implies that replacement lubricating greases must be found, especially in this era of extending the lifetime of DoD assets, with the consequent and unprojected demand for sources of replacement parts.4.3 One of the primary goals of this study was to take a broad spectrum of the lubricating greases used in PREB and do a comprehensive series of tests on them in order that their properties could be compared and, if necessary, potential replacement greases be identified. This study is also meant to be a design guide for choosing lubricating greases for future PREB applications. This guide represents a collective effort of many members of this community who span the spectrum from bearing manufacturers, original equipment manufactures (OEMs), grease manufacturers and suppliers, procurement specialists, and quality assurance representatives (QARs) from DoD and end users both inside and outside DoD.4.4 It is strongly recommend that, prior to replacing a grease in a PREB, all of the existing grease should be removed from the bearing. Reactions may occur between incompatible greases resulting in severely degraded performance. When users have more than one type of grease in service, maintenance practices must be in place to avoid accidental mixing of greases. In addition, all fluids used specifically to prolong storage life of PREBs (preservatives) should be removed prior to lubricating the bearings. Reactions may occur which would degrade the grease.4.5 The base oils, thickeners, and additives dictates grease performances. The properties of many base oils can be found in the previous study (Guide F2161). This study included a discussion of elastohydrodynamic lubrication theory.1.1 This guide is a tool to aid in the choice of lubricating grease for precision rolling element bearing applications. The recommendations in this guide are not intended for general purpose bearing applications There are two areas where this guide should have the greatest impact: (1) when lubricating grease is being chosen for a new bearing application and (2) when grease for a bearing has to be replaced because the original grease specified for the bearing can no longer be obtained. The Report (see Section 5) contains a series of tests on a wide variety of greases commonly used in bearing applications to allow comparisons of those properties of the grease that the committee thought to be most important when making a choice of lubricating grease. Each test was performed by the same laboratory. This guide contains a listing of the properties of greases by base oil type, that is, ester, perfluoropolyether (PFPE), polyalphaolefin (PAO), and so forth. This organization is necessary since the operational requirements in a particular bearing application may limit the choice of grease to a particular base oil type and thickener due to its temperature stability, viscosity index or temperature-vapor pressure characteristics, etc. The guide provides data to assist the user in selecting replacement greases for those greases tested that are no longer available. The guide also includes a glossary of terms used in describing/discussing the lubrication of precision and instrument bearings.1.2 The lubricating greases presented in this guide are commonly used in precision rolling element bearings (PREB). These greases were selected for the testing based on the grease survey obtained from DoD, OEM and grease manufactures and evaluated according to the test protocol that was designed by Subcommittee F34 on Tribology. This test protocol covers the essential requirements identified for precision bearing greases. The performance requirements of these greases are very unique. They are dictated by the performance expectations of precision bearings including high speed, low noise, extended life, and no contamination of surrounding components by the bearing’s lubricant system. To increase the reliability of test data, all tests were performed by a DoD laboratory and three independent testing laboratories. There were no grease manufacturer’s data imported except for base oil viscosity. Most of tests were performed by U.S. Army Tank–Automotive Research, Development and Engineering Center (TARDEC) and three independent laboratories, and the results were monitored by the Naval Research Laboratory (NRL). This continuity of testing should form a solid basis for comparing the properties of the multitude of lubricating greases tested by avoiding some of the variability introduced when greases are tested by different laboratories using different or even the “same” procedures. Additional test data will be considered for inclusion, provided the defined protocol is followed and the tests are performed by independent laboratories.1.3 This study was a part of DoD Aging Aircraft Replacement Program and supported by Defense Logistic Agent (DLA) and Defense Supply Center Richmond (DSCR).21.4 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.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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定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

2.1 Procedure A covers the determination of the equation of the curve relating resistance and temperature where the curve approximates a parabola. This test method may be used for wire of any metal or alloy over the temperature interval appropriate to the material.2.2 Procedure B covers the determination of the mean temperature coefficient of resistance for wire of any metal or alloy over the temperature interval appropriate to the material.1.1 This test method covers determination of the change of resistance with temperature of alloy wires used for resistance standards and precision resistors for electrical apparatus.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 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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4.1 This test method provides a means for measuring linear dimensions. Accurate measurement of dimensions can be critical to meeting specifications and characterizing process performance.4.2 This test method should not be applied to tolerance ranges of less than 3 mm (1/8 in.) when it is preferable that test error does not exceed 30 % of tolerance range. See Precision and Bias Section for gauge repeatability and reproducibility results.4.3 This test method does not address acceptability criteria. These need to be jointly determined by the user and producer of the product.1.1 This test method covers the measurement of linear dimension of flexible packages and packaging materials. It is recommended for use with an allowable tolerance range of 3 mm (1/8 in.) or greater based on gauge repeatability and reproducibility presented in the Precision and Bias section.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.3 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.

定价： 515元 / 折扣价： 438 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车

定价： 646元 / 折扣价： 550 元 加购物车

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