With the increasing environmental protection requirements, the emission standards for volatile organic compounds (VOCs) have set higher requirements for the sealing performance of mechanical equipment. This paper compares the national and Guangdong provincial standards regarding VOCs emissions and highlights their impact on the selection of mechanical seals for petrochemical pumps. The classification of hazardous chemicals and relevant regulations and standards are continuously evolving worldwide, which significantly affects the design and application of mechanical seals for petrochemical pumps. The fourth edition of API 682—2014 Pumps—Shaft Sealing Systems for Centrifugal and Rotary Pumps introduced a mechanical seal selection method based on the Material Safety Data Sheet (MSDS), which involves selecting seals according to the classification, concentration, and occupational exposure limits of hazardous chemicals. By investigating and tracking the latest domestic and international regulations and standards on the classification of hazardous chemicals, and combining them with practical applications, this paper attempts to apply the new API standard method to select mechanical seals for some practical applications. This approach aims to enhance the understanding of hazardous chemical classification and recognize the impact of pump media hazards on the selection of mechanical seals. The analysis and attempts indicate that the design and selection of mechanical seals for petrochemical pumps need to keep pace with the times to ensure safety, environmental protection, and human health.

随着环保要求的提高，相关挥发性有机物（VOCs）物料排放标准对机械设备密封的排放提出较高要求。文中对比国家标准和广东省地方标准有关VOCs物料排放标准，指出其对相关石油化工泵机械密封选型的影响。国内外对化学危险品分类法规、标准在不断发展变化，化学危险品的危险分类及其危害属性对石油化工泵用机械密封的设计应用也产生较大影响。API 682—2014 Pumps—Shaft Sealing Systems for Centrifugal and Rotary Pumps 第4版公布了一种基于材料安全数据表（MSDS）的机械密封选型方法，即按照相关危险化学品分类、含量及职业暴露接触限值等信息设计选用机械密封。文中通过调查、追踪国内外最新有关危险化学品分类的法规、标准，结合实际，按API标准新方法对一些实际应用中的机械密封选型进行了尝试，以进一步提高对相关危险化学品分类的认识，认清泵送介质的危害属性及其对泵机械密封选型的影响。通过上述分析与尝试，指出石油化工泵机械密封的设计选用需与时俱进，使机械密封设计更安全、更有益于环保和人类健康。