1.1 这些实践涵盖了通过力测量标准对静态或准静态试验机（可能有也可能没有力指示器）的拉伸或压缩或两者进行力校准和验证的程序。这些做法并非测试机器的完整采购规范。 1.2 试验机可以通过以下三种方法之一或其组合进行验证。每种方法都需要特定的测量不确定度，显示国际单位制（SI）的计量可追溯性。 1.2.1 使用标准砝码， 1.2.2 使用等臂平衡和标准重量，或 1.2.3 弹性力测量标准的使用。 1.3 程序 1.2.1 – 1.2.3 适用于与试验机相关的测力系统的校准和验证，包括刻度盘、刻度盘、标记或未标记的记录器图表、数字显示器等测力指示器。 在所有情况下，买方/业主/用户必须指定要验证的测力系统，并将其纳入校准和验证的证书和报告中 . 1.4 单位-- 以国际单位制或英寸-磅单位表示的值应单独视为标准值。每个系统中所述的值不一定是完全等效的； 因此，为确保符合标准，每个系统应独立使用，两个系统的值不得组合。 1.4.1 本标准可使用其他非国际单位制力单位，如硬度试验机常用的千克力（kgf） 1.5 试验机数据系统的显示器/打印输出上显示的力，无论是瞬时的、延迟的、存储的还是重新传输的，都要按照以下规定进行验证 1.2.1 , 1.2.2 ，或 1.2.3 ，并且符合第节中规定的规格 16 ，遵守惯例 E4 . 1.6 这些规程的要求限制了校准试验机时测量不确定度的主要组成部分。 这些标准实践不要求将允许的力测量误差减少到校准过程中遇到的测量不确定度。因此，当力测量误差与测量不确定度相结合时，使用这些实践验证的试验机可能会产生与真实力的偏差大于±1.0%。 1.7 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 5.1 在许多行业中，以多种方式使用施加和指示力的测试机器。它们可以在研究实验室中用于测量材料性能，也可以在生产线上用于确定产品的装运资格。无论试验机的最终用途是什么，用户都有必要知道施加和指示的力的大小可以通过国家计量研究所（NMI）追溯到国际单位制（SI）。 实践中的程序 E4 可用于校准这些试验机，以便测量的力可追溯到SI。SI可追溯性的一个关键因素是校准中使用的力测量标准具有已知的力特性，并且已经按照规程进行了校准 E74 . 5.2 实践中的程序 E4 可供使用、制造和提供测试机器和相关仪器校准服务的人使用。

1.1 These practices cover procedures for the force calibration and verification, by means of force measurement standards, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicators). These practices are not intended to be complete purchase specifications for testing machines. 1.2 Testing machines may be verified by one of the three following methods or combination thereof. Each of the methods require a specific measurement uncertainty, displaying metrological traceability to The International System of Units (SI). 1.2.1 Use of standard weights, 1.2.2 Use of equal-arm balances and standard weights, or 1.2.3 Use of elastic force measurement standards. 1.3 The procedures of 1.2.1 – 1.2.3 apply to the calibration and verification of the force-measuring systems associated with the testing machine, including the force indicators such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-measuring system(s) to be verified and included in the certificate and report of calibration and verification . 1.4 Units— 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. 1.4.1 Other non-SI force units may be used with this standard such as the kilogram-force (kgf) which is often used with hardness testing machines 1.5 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.2.1 , 1.2.2 , or 1.2.3 , and are within the specifications stated in Section 16 , comply with Practices E4 . 1.6 The requirements of these practices limit the major components of measurement uncertainty when calibrating testing machines. These Standard Practices do not require the allowable force measurement error to be reduced by the amount of the measurement uncertainty encountered during a calibration. As a result, a testing machine verified using these practices may produce a deviation from the true force greater than ±1.0 % when the force measurement error is combined with the measurement uncertainty. 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. ====== Significance And Use ====== 5.1 Testing machines that apply and indicate force are used in many industries, in many ways. They might be used in a research laboratory to measure material properties, or in a production line to qualify a product for shipment. No matter what the end use of the testing machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to calibrate these testing machines so that the measured forces are traceable to the SI. A key element of traceability to the SI is that the force measurement standards used in the calibration have known force characteristics, and have been calibrated in accordance with Practice E74 . 5.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.