1.1本规程涵盖了严重腐蚀应用的包络垫圈的设计、尺寸、分类和构造。外壳作为复合垫片的耐腐蚀构件，是非金属材料，如聚四氟乙烯或相关材料。插入件是非金属衬垫材料，有或没有金属加固。F868类涵盖了其他类型的复合垫片。 1.2以英寸-磅为单位的数值应视为标准值。括号中给出的值仅供参考。 1.3本标准无意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和健康实践，并确定监管限制的适用性。

1.1 This practice covers the designs, sizes, classifications, and construction of enveloped gaskets for severe corrosive applications. The envelope serves as the corrosion resistant member of the composite gasket and is a nonmetallic material such as polytetrafluoroethylene or related materials. The inserts are nonmetallic gasketing materials with or without metal reinforcement. Other types of composite gaskets are covered in Classification F868. 1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.