1.1 在现场使用的汽油、涡轮增压、直喷（GTDI）发动机中观察到了不理想的正时链条磨损，相关实验室发动机测试的数据表明，适当配方的发动机润滑会影响链条磨损。已经开发了一种实验室发动机测试，为筛选润滑油提供了一种方法。实验室发动机测试为216 h，在不同条件下进行，并且在试验结束时确定的正时链长度的增加是主要结果。这种测试方法通常被称为X序列链条磨损（CW）测试。 1.2 以国际单位制表示的数值应视为标准。SI单位后括号中给出的值仅供参考，不被视为标准值。 1.2.1 例外 如果没有直接的SI等效物，如螺纹、国家管道螺纹/直径、管道尺寸或指定的单一来源设备。 1.3 目录: 部分 范围 1. 参考文件 2. 术语 3. 试验方法总结 4. 意义和用途 5. 仪器 6. 测试发动机 6.1 试剂和材料 7. 仪器的准备 8. 正时链条的准备、安装和测量 8.20 试验台安装 8.21 电子节气门控制器 8.21.17 温度测量 8.23 压力测量 8.24 流量测量 8.25 窜流量 8.26 支架校准 9 测试程序 10 预测试程序和发动机磨合 10.1 发动机起动程序 10.2 测试顺序 10.3 发动机停机程序 10.4 窜流量测量 10.5 参数日志记录 10.6 油耗计算 10.7 一般维护 10.8 特殊维护程序 10.9 窜流量调整 10.10 诊断数据审查 11 测试结果 12 汇报 13 精度和偏差 14 关键词 15 附件 ASTM TMC组织 附件A1 ASTM TMC:校准程序 附件A2 ASTM TMC:维护活动 附件A3 ASTM TMC:相关信息 附件A4 发动机和支架零件 附件A5 安全注意事项 附件A6 引擎重建模板 附件A7 发动机构建记录 附件A8 气缸盖构造 A8.1 气缸孔径测量 A8.2 轴承轴颈测量 A8.3 发动机零件照片、示意图和图表 附件A9 控制和数据采集要求 附件A10 油尺油位至充油转换 附件A11 序列X报表和数据采集 附件A12 附录 材料和信息来源 附录X1 发动机固定支架的建议设计 附录X2 1.4 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。 1.5 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 该试验方法评估了汽车发动机油在抑制正时中的润滑效率- 在选择加速正时链条磨损的操作条件下延长链条。在开发试验程序的操作条件时，使用了已知磨损性能的不同质量的参考油。 5.2 该测试方法可用于筛选润滑剂，以获得发动机正时链的满意润滑，并适用于汽油、汽车和发动机机油规格。预计它将用于发动机润滑油的规格和分类，例如: 5.2.1 ILSAC GF-6。 5.2.2 规格 D4485 . 5.2.3 SAE分类J183。

1.1 Undesirable timing-chain wear has been observed with gasoline, turbocharged, direct-injection (GTDI) engines in field service, and data from correlating laboratory engine tests have shown that chain wear can be affected by appropriately formulated engine lubricating. A laboratory engine test has been developed to provide a means for screening lubricating oils for that specific purpose. The laboratory engine test is 216 h in length, conducted under varying conditions, and the increase in timing-chain length determined at the end of test is the primary result. This test method is commonly known as the Sequence X, Chain Wear (CW) Test. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.2.1 Exception— Where there is no direct SI equivalent such as screw threads, national pipe threads/diameters, tubing size, or specified single source equipment. 1.3 Table of Contents: Section Scope 1 Referenced Documents 2 Terminology 3 Summary of Test Method 4 Significance and Use 5 Apparatus 6 Test Engine 6.1 Reagents and Materials 7 Preparation of Apparatus 8 Timing-chain Preparation, Installation, and Measurement 8.20 Test Stand Installation 8.21 Electronic Throttle Controller 8.21.17 Temperature Measurement 8.23 Pressure Measurement 8.24 Flowrate Measurement 8.25 Blowby Flowrate 8.26 Stand Calibration 9 Test Procedure 10 Pre-Test Procedure and Engine Break-In 10.1 Engine Start-up Procedures 10.2 Test Sequence 10.3 Engine Shutdown Procedures 10.4 Blowby Flowrate Measurement 10.5 Parameter Logging 10.6 Oil Consumption Calculation 10.7 General Maintenance 10.8 Special Maintenance Procedures 10.9 Blowby Flowrate Adjustment 10.10 Diagnostic Data Review 11 Test Results 12 Report 13 Precision and Bias 14 Keywords 15 ANNEXES ASTM TMC Organization Annex A1 ASTM TMC: Calibration Procedures Annex A2 ASTM TMC: Maintenance Activities Annex A3 ASTM TMC: Related Information Annex A4 Engine and Stand Parts Annex A5 Safety Precautions Annex A6 Engine Rebuild Templates Annex A7 Engine Build Records Annex A8 Cylinder Head Build A8.1 Cylinder Bore Measurement A8.2 Bearing Journal Measurements A8.3 Engine Part Photographs, Schematics and Figures Annex A9 Control and Data Acquisition Requirements Annex A10 Dipstick Oil Level to Charge Conversions Annex A11 Sequence X Report Forms and Data Acquisition Annex A12 APPENDIXES Sources of Materials and Information Appendix X1 Suggested Designs for Engine Fixing Brackets Appendix X2 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. ====== Significance And Use ====== 5.1 This test method evaluates an automotive engine oil's lubricating efficiency in inhibiting timing-chain lengthening under operating conditions selected to accelerate timing-chain wear. Varying quality reference oils of known wear performance were used in developing the operating conditions of the test procedure. 5.2 The test method can be used to screen lubricants for satisfactory lubrication of an engine timing chain and has application in gasoline, automotive, engine-oil specifications. It is expected to be used in specifications and classifications of engine lubricating oils, such as the following: 5.2.1 ILSAC GF-6. 5.2.2 Specification D4485 . 5.2.3 SAE Classification J183.