1.1 本指南概述了发泡趋势评估协议及其适当使用。 1.2 ASTM试验方法 D3519 和 D3601 2013年撤销。虽然每种方法都有一些实用性，但两种方法都不能可靠地预测使用中的发泡趋势。自试验方法 D3519 和 D3601 首次采用时，已经开发了几个更具预测性的测试协议。然而，众所周知，没有任何单一的协议普遍适用于预测水溶性金属加工液（MWF）的发泡趋势。 1.3 此外，没有公认的参考标准流体（MWF或泡沫- 对照添加剂）。相反，重要的是在所有测试中包括相关参考样品。 1.4 参考和试验流体浓缩物的年龄可能是其发泡行为的一个重要因素。理想情况下，在稀释以进行泡沫测试之前，新制备的浓缩液应在实验室室温下保持至少一周。这确保了任何中和反应都达到平衡，并使微乳液达到粒径平衡。在筛选试验期间，也建议在精矿经过热老化和冷冻/解冻处理后测试液体。 1.5 稀释水的质量会对泡沫性能产生重大影响。通常，用硬水稀释的浓缩液的泡沫比用软水、去离子水或反渗透水稀释的浓缩液的泡沫小。强烈建议使用预期稀释水质范围进行筛选试验。 1.6 测试流体的温度可能对发泡性能有重大影响。一般来说，测试流体应在与实际应用和过程非常相似的温度下保存和测试。 1.7 在泡沫评估测试期间，测试设备的清洁度至关重要。实验室器皿上的残留痕迹会显著影响观察到的测试液起泡趋势。 最佳做法是使用某种化学清洁剂清洁任何玻璃器皿或其他容器，以减少交叉污染的风险。 1.8 单位- 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.9 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.10 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《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 再循环多壁光纤的过程会夹带气泡，这些气泡会积聚，形成泡沫。 4.2 最理想的情况是，气泡在产生后会迅速爆裂。然而，气泡持续性受多壁光纤化学和能量引入再循环多壁光纤的机制的影响。 4.2.1 将能量传递给再循环MWF的主要机制是: 4.2.1.1 湍流- 高速（通常>0.75 m 3. 最小值 –1 ; >最小200加仑 –1 ). 4.2.1.2 撞击- MWF撞击刀具-工件区域时产生的能量。 4.2.1.3 离心力- MWF通过旋转工具或工件的力移动。 4.3 当气泡持续存在时，它们往往会积聚成泡沫。持久性泡沫可以: 4.3.1 抑制热传递； 4.3.2 引起泵叶轮气蚀； 4.3.3 污物过滤器； 4.3.4 MWF集水坑溢流； 4.3.5 防止正确润滑； 4.3.6 有助于MWF雾的形成，包括生物气溶胶分散；和 4.3.7 造成工厂的安全和卫生危害。 4.4 为了防止MWF泡沫积聚的不利影响，将化学药剂配制成MWF浓缩液，添加到罐侧，或两者兼而有之。 4.5 实验室测试用于预测最终应用中的MWF发泡特性。然而，没有一种单独的测试是普遍适用的。 4.6 本指南回顾了通常用于评估最终用途稀释MWF发泡趋势和泡沫控制剂对MWF发泡趋势的影响的测试协议。

1.1 This guide provides an overview of foaming tendency evaluation protocols and their appropriate use. 1.2 ASTM Test Methods D3519 and D3601 were withdrawn in 2013. Although each method had some utility, neither method reliably predicted in-use foaming tendency. Since Test Methods D3519 and D3601 were first adopted, several more predictive test protocols have been developed. However, it is also common knowledge that no single protocol is universally suitable for predicting water-miscible metalworking fluid (MWF) foaming tendency. 1.3 Moreover, there are no generally recognized reference standard fluids (either MWF or foam-control additive). Instead it is important to include a relevant reference sample in all testing. 1.4 The age of the reference and test fluid concentrates can be an important factor in their foaming behavior. Ideally, freshly prepared concentrates should be held at laboratory room temperature for at least one week before diluting for foam testing. This ensures that any neutralization reactions have reached equilibrium and enables microemulsions to reach particle size equilibrium. During screening tests, it is also advisable to test fluids after the concentrates have been heat aged and subjected to freeze/thaw treatment. 1.5 The dilution water quality can have a major impact on foaming properties. In general, fluid concentrates diluted with hard water will foam less than those diluted with soft, deionized, or reverse osmosis water. Screening tests using the expected range of dilution water quality are highly recommended. 1.6 The temperature of the tested fluids can have a major impact on foaming properties. In general, test fluids should be held and tested at temperatures that closely mimic the real-world application and process. 1.7 Cleanliness of test apparatus is critical during foam evaluation testing. Traces of residue on labware can significantly impact the observed foaming tendency of a test fluid. Best practice is to clean any glassware or other vessels using some version of a chemical cleaner that will alleviate any risk of cross contamination. 1.8 Units— The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. 1.9 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. 1.10 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 ====== 4.1 The process of recirculating MWFs entrains air bubbles which can accumulate, forming foam. 4.2 Optimally, air bubbles burst open quickly after they are created. However, air bubble persistence is affected by MWF chemistry and the mechanisms by which energy is introduced into recirculating MWFs. 4.2.1 The primary mechanisms imparting energy into recirculating MWFs are: 4.2.1.1 Turbulent Flow— The high velocity (typically >0.75 m 3 min –1 ; >200 gal min –1 ). 4.2.1.2 Impaction— Energy generated when MWF strikes the tool-workpiece zone. 4.2.1.3 Centrifugal Force— MWF moved by the force of rotating tools or work pieces. 4.3 When air bubbles persist, they tend to accumulate as foam. Persistent foam can: 4.3.1 Inhibit heat transfer; 4.3.2 Cause pump impeller cavitation; 4.3.3 Foul filters; 4.3.4 Overflow from MWF sumps; 4.3.5 Prevent proper lubrication; 4.3.6 Contribute to MWF mist formation, including bioaerosol dispersion; and 4.3.7 Contribute to safety and hygiene hazards in the plant. 4.4 To prevent the adverse effects of MWF foam accumulation, chemical agents are either formulated into MWF concentrate, added tankside, or both. 4.5 Laboratory tests are used to predict MWF foaming characteristics in end-use applications. However, no individual test is universally appropriate. 4.6 This guide reviews test protocols commonly in use to evaluate end-use diluted MWF foaming tendency and the impact of foam-control agents on MWF foaming tendency.