1.1 本试验方法包括使用手动蒸汽压力仪表来确定在真空中施加的原油蒸汽压力。该测试方法适用于测试蒸汽压力在25 kPa和180 37.8时的kPa 蒸汽/液体比为4:1至0.25:1（X=4至0.25，见 3.2.4 ). 注1: 本试验方法适用于测定0℃以下温度下原油的蒸汽压 °C至60 °C，压力高达500 kPa，但精度和偏差声明（见第节 15 )可能不适用。 1.2 本试验方法主要用于现场条件下，用于立即评估储存、运输或操作用途的蒸汽压力。 1.3 本试验方法不适用于监护转移应用。 试验方法 第6377页 应用于托管转移申请。 1.4 考虑到低沸点组分的分压对总蒸汽压的贡献很大，该试验方法为原料中存在轻馏分提供了合理的确认。 1.5 该测试方法允许直接从样品源采集原油样品并随后测量其蒸汽压。收集的样品也可以转移到自动蒸汽压力仪器，例如用于测试方法 第6377页 现场测试设备适用于运输，前提是使用合适的外包装，以满足运输管辖区内危险货物运输的规定。 1.6 该试验方法允许测定倾点低于0的原油样品的蒸汽压 °C，并在取样条件下流动，以允许进入仪器。 1.7 以国际单位制表示的值应视为标准值。 1.7.1 例外情况- 本标准包括其他计量单位，以便于在多个司法管辖区使用。 1.8 本标准并不旨在解决与其使用相关的所有安全问题（如有）。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。 1.9 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 原油在不同汽液比下的蒸汽压是运输、储存和炼油厂操作的重要物理性质。 5.2 原油的蒸汽压力对于原油生产商、调节器、运输商和炼油厂的一般处理、运输和初始炼油厂处理至关重要。 5.3 直接样品收集和随后的就地蒸汽压力测量无需进一步处理样品，消除了样品中轻烃材料的潜在损失。取样和试验的结合可能产生比试验方法更高的结果 第323页 . 5.4 蒸汽压测量前样品的冷却和空气饱和度（按照试验方法的要求 第323页 )在本测试方法中不需要。

1.1 This test method covers the use of manual vapor pressure instruments to determine the vapor pressure of crude oils exerted in a vacuum. This test method is suitable for testing samples that exert a vapor pressure between 25 kPa and 180 kPa at 37.8 °C at vapor/liquid ratios from 4:1 to 0.25:1 (X = 4 to 0.25, see 3.2.4 ). Note 1: This test method is suitable for the determination of the vapor pressure of crude oils at temperatures from 0 °C to 60 °C and pressures up to 500 kPa, but the precision and bias statements (see Section 15 ) may not be applicable. 1.2 This test method is meant primarily for use under field conditions for immediate evaluation of vapor pressure for storage, transport, or operational uses. 1.3 This test method is not intended for use in custody transfer applications. Test Method D6377 shall be used for custody transfer applications. 1.4 This test method provides a reasonable confirmation for the presence of light ends in the source material given that the partial pressure of low boiling components contribute significantly to total vapor pressure. 1.5 This test method allows both sample collection and subsequent vapor pressure measurement of crude oil samples directly from the sample source. The collected sample may also be transferred to an automated vapor pressure instrument such as used for Test Method D6377 . The field test apparatus is suitable for transportation provided suitable over-pack is used to meet the regulations for the transportation of dangerous goods in the transportation jurisdiction(s). 1.6 This test method allows the determination of vapor pressure for crude oil samples having pour points below 0 °C and flow at the sampling conditions to allow inlet to the apparatus. 1.7 The values stated in SI units are to be regarded as standard. 1.7.1 Exception— Other units of measurement are included in this standard for ease of use in multiple jurisdictions. 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. ====== Significance And Use ====== 5.1 Vapor pressure of crude oil at various vapor/liquid ratios is an important physical property for transport, storage, and refinery operations. 5.2 Vapor pressure of crude oil is important to crude oil producers, regulators, transporters and refiners for general handling, transportation, and initial refinery treatment. 5.3 The direct sample collection and subsequent, in place, vapor pressure measurement without the need for further sample handling eliminates the potential loss of light hydrocarbon material from the sample. The combination of sampling and testing may produce higher results than Test Method D323 . 5.4 Chilling and air saturation of the sample prior to the vapor pressure measurement (as required in Test Method D323 ) is not required in this test method.