分层通常称为“起层”、“掉皮”、“空鼓”。笔者认为“分层”这一名称能较确切地表达一阶段管的这种缺陷。露天铺设的一阶段管线常出现端面裂纹(一般称为端面环裂),经劈开观察,是分层扩大到端面的结果,故也应称层裂才确切 Layering is often referred to as “layering,” “skinning,” or “hollowing.” The author believes that the name “layered” can more accurately express this kind of defect in the first-stage management. In the open-air laying pipeline, there is often a face crack (generally referred to as a face ring crack). After observation, it is the result of stratification and expansion to the end face. Therefore, it should be said that the spallation is exact.